Variants of sirtuin 6 for the treatment of muscular diseases

Abstract

The present invention relates to variants of sirtuin 6 for the treatment of muscular diseases, in particular frailty syndrome and sarcopenia.

Description

VARIANTS OF SIRTUIN 6 FOR THE TREATMENT OF MUSCULARDISEASESFIELD OF INVENTION

[0001] The present invention relates to the field of the treatment or prevention of muscular diseases. It relates in particular to a prophylactic and / or therapeutic composition for muscular diseases, particularly frailty syndrome and sarcopenia, which contains a variant of SIRT6.BACKGROUND OF INVENTION

[0002] Muscular diseases encompass a wide range of disorders that affect muscle function, leading to weakness, wasting, and reduced physical performance. These diseases can be genetic, inflammatory, metabolic, endocrine, and / or due to aging. They affect skeletal muscles, which are responsible for voluntary movements, and can severely impact the quality of life.

[0003] Examples of muscular diseases include sarcopenia and frailty syndrome. Sarcopenia is an age-related condition characterized by the progressive loss of muscle mass, strength, and endocrine, paracrine and autocrine function. This disease typically accelerates with aging. The loss of muscle mass is not merely a consequence of aging but involves a complex interplay of factors, including hormonal changes, inflammation, and reduced physical activity. Frailty syndrome is a related condition, often overlapping with sarcopenia. It is a clinical syndrome marked by decreased physiological reserves and increased vulnerability to stressors. Frailty syndrome encompasses multiple domains, including weakness, slowness, fatigue, and weight loss. This disease includes a broad spectrum of physical and cognitive decline.

[0004] The management of sarcopenia and frailty is challenging due to limited treatment options. Current treatments are limited and primarily involve exercise and nutritional interventions, which are often insufficient, especially in advanced stages. Moreover, the complex and multifactorial nature of these conditions hinders the development of targeted therapies.

[0005] In addition to muscle loss, the pathophysiology of muscular diseases, including sarcopenia and frailty syndrome, is influenced by several endocrine, paracrine, and autocrine factors, notably inflammatory cytokines leading to chronic low-grade inflammation (e.g., cytokines like IL-6, TNF-a, and IL-ip), and myokines (z.e., cytokines or peptides produced by muscle fibers in response to stimulus such as contraction). Addressing the endocrine, paracrine, and autocrine aspects of muscular diseases in parallel of loss of muscle mass is thus crucial for the treatment of these diseases.

[0006] Sirtuin 6 (SIRT6) plays important roles in multiple regulatory functions including DNA repair, heterochromatin regulation, and telomere maintenance. In particular, certain variants of SIRT6 have been previously described for the treatment of several diseases such as age-related diseases (WO2022241228) or non-alcoholic fatty liver disease (WO2024121363).

[0007] The present invention provides a solution for treating muscular diseases, in particular aspects related to loss of muscle mass and alteration of endocrine, paracrine, and autocrine functions, using SIRT6.SUMMARY

[0008] The present invention relates to an isolated nucleic acid molecule encoding a sirtuin 6 (SIRT6) protein having at least 75% identity with sequence SEQ ID NO: 1, for use for preventing and / or treating a muscular disease in a subject in need thereof.

[0009] The present invention also relates to an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting ofa substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, for use for preventing and / or treating a muscular disease in a subject in need thereof.

[0010] In some embodiments, the nucleic acid molecule is of sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8.

[0011] The present invention further relates to an isolated polypeptide encoded by a nucleic acid molecule according to the invention, for use for preventing and / or treating a muscular disease.

[0012] In some embodiments, the polypeptide is of sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4.

[0013] The present invention further relates to a vector comprising the isolated nucleic acid molecule according to the invention, for use for preventing and / or treating a muscular disease.

[0014] In some embodiments, the vector is selected from the group consisting of an adeno-associated viral vector (AAV), an extracellular vesicle-based AAV vector such as an exosome-associated AAV vector (exo-AAV), an extracellular vesicle such as an exosome, an adenoviral vector, a retroviral vector, a herpes virus vector, a plasmid, and a naked nucleic acid molecule such as a DNA molecule or a mRNA molecule.

[0015] In some embodiments, the vector is a viral vector selected from the group consisting of an adeno-associated viral vector (AAV), an adenoviral vector a retroviral vector, and a herpes virus vector.

[0016] In some embodiments, the vector is an extracellular vesicle-based vector selected from the group consisting of an exosome-associated AAV vector (exo-AAV), and an extracellular vesicle.

[0017] In some embodiments, the vector is selected from the group consisting of a plasmid, a mRNA, and a naked DNA molecule.

[0018] In some embodiments, the vector is a SIRT6-loaded extracellular vesicle.

[0019] The present invention further relates to a composition comprising an isolated nucleic acid molecule according to the invention, or an isolated polypeptide according to the invention, or a vector according to the invention, for use for preventing and / or treating a muscular disease, preferably wherein said composition is a suspension.

[0020] The present invention further relates to a cell comprising the polypeptide according to the invention, the cell being preferably transfected with an isolated nucleic according to the invention, or a vector according to the invention, for use for preventing and / or treating a muscular disease.

[0021] In some embodiments, the cell is a progenitor cell.

[0022] In some embodiments, the progenitor cell is a muscle progenitor cell.

[0023] In some embodiments, the muscle progenitor cell is a skeletal muscle progenitor cell.

[0024] The present invention further relates to a pharmaceutical composition comprising (i) an isolated nucleic acid molecule according to the invention, or an isolated polypeptide according to the invention, or a vector according to the invention, and (ii) a pharmaceutically acceptable excipient, for use for preventing and / or treating a muscular disease.

[0025] In some embodiments, the muscular disease is characterized by loss of muscle mass and alteration of the endocrine function of the muscle.

[0026] In some embodiments, the muscular disease is a geriatric muscular disease.

[0027] In some embodiments, the muscular disease is selected from the group consisting of frailty syndrome and sarcopenia.

[0028] In some embodiments, the muscular disease is frailty syndrome.

[0029] In some embodiments, the muscular disease is sarcopenia.

[0030] The present invention further relates to a method of preventing and / or treating a muscular disease in a subject, comprising administering to said subject a therapeutically effective amount of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or of an isolated polypeptide encoded by the same; or of a pharmaceutical composition comprising the same.

[0031] In some embodiments, the muscular disease is characterized by loss of muscle mass and alteration of the endocrine function of the muscle.

[0032] In some embodiments, the muscular disease is a geriatric muscular disease.

[0033] In some embodiments, the muscular disease is selected from the group consisting of frailty syndrome and sarcopenia.

[0034] In some embodiments, the muscular disease is frailty syndrome.

[0035] In some embodiments, the muscular disease is sarcopenia.

[0036] In some embodiments, the isolated nucleic acid molecule is comprised in a vector selected from the group consisting of an adeno-associated viral vector (AAV), an exosome-associated AAV vector (exo-AAV), an exosome, an adenoviral vector, a retroviral vector, a herpes virus vector, a plasmid, and a naked DNA molecule.

[0037] In some embodiments, the vector is a viral vector selected from the group consisting of an adeno-associated viral vector (AAV), an adenoviral vector a retroviral vector, and a herpes virus vector.

[0038] In some embodiments, the vector is an exosome -based vector selected from the group consisting of an exosome-associated AAV vector (exo-AAV), and an exosome.

[0039] In some embodiments, the vector is selected from the group consisting of a plasmid, and a naked DNA molecule.

[0040] In some embodiments, the method further comprises administering to said subject another therapeutic agent.

[0041] The present invention further relates to the use of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or pharmaceutical composition comprising the same, for the manufacture of a medicament for preventing and / or treating a muscular disease.

[0042] In some embodiments, the muscular disease is characterized by loss of muscle mass and alteration of the endocrine function of the muscle.

[0043] In some embodiments, the muscular disease is a geriatric muscular disease.

[0044] In some embodiments, the muscular disease is selected from the group consisting of frailty syndrome and sarcopenia.

[0045] In some embodiments, the muscular disease is frailty syndrome.

[0046] In some embodiments, the muscular disease is sarcopenia.

[0047] The present invention further relates to a method for preventing loss of muscle mass in a subject, comprising administering to said subject an effective amount of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQID NO: 8; or of an isolated polypeptide encoded by the same; or of a composition comprising the same.

[0048] The present invention further relates to a method for preserving and / or restoring endocrine function of a muscle in a subject, comprising administering to said subject an effective amount of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or of an isolated polypeptide encoded by the same; or of a composition comprising the same.

[0049] In some embodiments, the endocrine function is related to lipid metabolism and / or glucose metabolism.

[0050] The present invention further relates to a method for increasing heterochromatin compaction in a eukaryotic cell, comprising contacting said cell with an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or with an isolated polypeptide encoded by the same.

[0051] The present invention further relates to a method for the reducing the expression of transposable elements (TEs) in a eukaryotic cell, comprising contacting said cell with an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or with an isolated polypeptide encoded by the same.

[0052] The present invention further relates to a method for the increasing histone 3 lysine 9 trimethylation (H3K9me3) in a eukaryotic cell, comprising contacting said cell with an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or with an isolated polypeptide encoded by the same.DEFINITIONS

[0053] In the present invention, the following terms have the following meanings:

[0054] “About”, when preceding a figure, means plus or less 10% of the value of said figure. It is to be understood that the value to which the term “about” refers is itself also specifically, and preferably, disclosed.

[0055] “Comprise” is intended to mean “contain”, “encompass” and “include”. In some embodiments, the term “comprise” also encompasses the term “consist of’.

[0056] “Sirtuin 6” also referred to as “SIRT6”, is intended to refer to the polypeptide with the Entrez Gene number 51548, and also non-limitatively relates to the NAD Dependent Protein Deacetylase Sirtuin-6, Regulatory Protein SIR2 Homolog 6, SIR2- Like Protein 6, SIR2L6, Sirtuin (Silent Mating Type Information Regulation 2, S. Cerevisiae, Homolog) 6, Sirtuin (Silent Mating Type Information Regulation 2 Homolog) 6, Sir2-Related Protein Type 6, Sirtuin Type 6 and EC 2.3.1.286.

[0057] “Isolated” refers to a nucleic acid molecule or polypeptide a that is removed from the initial biological context that has allowed to generate this nucleic acid molecule or polypeptide. In practice the biological context comprises at least a cell, or one or more enzyme(s).

[0058] “Nucleic acid”, also referred to as “polynucleotide”, refers to any polyribonucleotide or polydeoxyribonucleotide, which may be unmodified RNA or DNA or modified RNA or DNA. “Nucleic acid” or “polynucleotide” include, without limitation single- and double-stranded DNA, DNA that is a mixture of single- and double-stranded regions, single- and double- stranded RNA, and RNA that is a mixture of single- and double-stranded regions, hybrid molecules comprising DNA and RNA that may be single- stranded or, more typically, double- stranded or a mixture of single- and doublestranded regions. In addition, “Nucleic acid” or “polynucleotide” refers to triple-stranded regions comprising RNA or DNA or both RNA and DNA. The term “nucleic acid” or “polynucleotide” also includes DNAs or RNAs containing one or more modified bases and DNAs or RNAs with backbones modified for stability or for other reasons. "Modified" bases include, for example, tritylated bases and unusual bases such as inosine. A variety of modifications has been made to DNA and RNA; thus, “nucleic acid” or “polynucleotide” embraces chemically, enzymatically or metabolically modified forms of polynucleotides as typically found in nature, as well as the chemical forms of DNA and RNA characteristic of viruses and cells. "Polynucleotide" also embraces relatively short polynucleotides, often referred to as oligonucleotides.

[0059] “Polypeptide” refers to any peptide or protein comprising two or more amino acids joined to each other by peptide bonds or modified peptide bonds, i.e., peptide isosteres. "Polypeptide" refers to both short chains, commonly referred to as peptides, oligopeptides or oligomers, and to longer chains, generally referred to as proteins. Polypeptides may contain amino acid residues other than the 20 gene-encoded amino acid residues.

[0060] “Suspension” refers to a liquid mixture in which the active principle, such as the nucleic acid molecules, polypeptides, or vectors according to the invention, is / are floating in a liquid medium.

[0061] “Treating” or “treatment” or “alleviation” refers to therapeutic treatment and / or prophylactic or preventative measures, wherein the object is to prevent or slow down (lessen) the targeted pathologic condition or disorder, in particular a muscular disease, particularly frailty syndrome or sarcopenia. In other words, the terms refer to thetreatment, or the prevention, or both the treatment and the prevention, of a disease. Those in need of treatment include those already with said disorder as well as those prone to develop the disorder or those in whom the disorder is to be prevented. Preventing” refers to keeping from happening, and / or lowering the chance of the onset of, or at least one adverse effect or symptom of a muscular disease, particularly frailty syndrome or sarcopenia. An individual is successfully "treated" for a muscular disease, particularly frailty syndrome or sarcopenia, if, after receiving a therapeutic amount of the active principle, in particular the nucleic acid molecules, polypeptides, or vectors according to the present invention, the individual shows observable and / or measurable reduction in or absence of one or more of the symptoms associated with the muscular disease, particularly frailty syndrome or sarcopenia; improvement in quality of life issues. The above parameters for assessing successful treatment and improvement in the disease are readily measurable by routine procedures familiar to physician or authorized personnel. “Therapeutic amount” or “therapeutically effective amount” means level or amount of the therapeutic agent of the invention that is aimed at, without causing significant negative or adverse side effects to the target, (1) delaying or preventing the onset of a disease, disorder, or condition, in particular a muscular disease, particularly frailty syndrome or sarcopenia; (2) slowing down or stopping the progression, aggravation, or deterioration of one or more symptoms of the disease, disorder, or condition, in particular a muscular disease, particularly frailty syndrome or sarcopenia; (3) bringing about ameliorations of the symptoms of the disease, disorder, or condition, in particular a muscular disease, particularly frailty syndrome or sarcopenia; (4) reducing the severity or incidence of the disease, disorder, or condition, in particular a muscular disease, particularly frailty syndrome or sarcopenia; or (5) curing the disease, disorder, or condition, in particular a muscular disease, particularly frailty syndrome or sarcopenia. A therapeutically effective amount may be administered prior to the onset of the disease, disorder, or condition, in particular a muscular disease, particularly frailty syndrome or sarcopenia, for a prophylactic or preventive action. Alternatively, or additionally, the therapeutically effective amount may be administered after initiation of the disease, disorder, or condition, in particular a muscular disease, particularly frailty syndrome or sarcopenia, for a therapeutic action.

[0062] “Individual” refers to an animal, preferably a mammal, more preferably a human. In one embodiment, the individual is a male. In another embodiment, the individual is a female. In one embodiment, an individual may be a “patient”, i.e. a warmblooded animal, more preferably a human, who / which is awaiting the receipt of, or is receiving medical care or was / is / will be the object of a medical procedure, or is monitored for the development of a muscular disease, particularly frailty syndrome or sarcopenia. In one embodiment, the individual is an adult (for example a subject above the age of 18). In another embodiment, the individual is a child (for example a subject below the age of 18).DETAILED DESCRIPTION

[0063] The present invention relates to an isolated nucleic acid molecule encoding a sirtuin 6 (SIRT6) protein having at least 75% identity with sequence SEQ ID NO: 1, for use for preventing and / or treating a muscular disease.

[0064] In some embodiments, the SIRT6 protein is a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1.

[0065] The present invention thus also relates to an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, for use for preventing and / or treating a muscular disease.

[0066] As used herein the expression “at least 75% identity” encompasses 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, and 99% and 99.5% identity.

[0067] SIRT6 may be the wild-type (unmodified) SIRT6, or a variant thereof. Wild type SIRT6 has the amino acid sequence of SEQ ID NO: 1. Within the scope of the presentinvention, the variant of sirtuin 6 (SIRT6) has at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, therefore the polypeptide encoded by the isolated nucleic acid molecule does not have 100% sequence identity with SEQ ID NO: 1.

[0068] Hence, in one embodiment, the polypeptide encoded by the isolated nucleic acid molecule is a wild-type or unmodified SIRT6 having the amino acid sequence of SEQ ID NO: 1. In another embodiment, the polypeptide encoded by the isolated nucleic acid molecule is a SIRT6 variant having less than 100% sequence identity with SEQ ID NO: 1.

[0069] The level of identity of 2 polypeptides may be performed by using any one of the known algorithms available from the state of the art. Illustratively, the amino acid identity percentage may be determined using the CLUSTAL W software (version 1.83), the parameters being set as follows:- for slow / accurate alignments: (1) Gap Open Penalty: 10.00; (2) Gap Extension Penalty:0.1; (3) Protein weight matrix: BLOSUM;- for fast / approximate alignments: (4) Gap penalty: 3; (5) K-tuple (word) size: 1; (6) No. of top diagonals: 5; (7) Window size: 5; (8) Scoring Method: PERCENT.

[0070] Within the scope of the invention the sequence SEQ ID NO: 1 refers to the 361 amino acid residues sequence of wild type SIRT6 polypeptide. In practice, substitutions N308K and A313S refer to the mutations of the codon encoding the naturally occurring Asn (N) amino acid residue at position 308 in the SIRT6 polypeptide, and the Ser (S) amino acid residue at position 313 in the SIRT6 polypeptide, respectively.

[0071] Within the scope of the invention the sequence SEQ ID NO: 5 refers to the 1,068 nucleotides (bp) sequence of wild type (unmodified) SIRT6 polypeptide.

[0072] In some embodiments, the naturally occurring Asn (N) amino acid residue at position 308 in the SIRT6 polypeptide is encoded by codon “aac” at positions 922 to 924 of SEQ ID NO: 5. In some embodiments, the naturally occurring Ser (S) amino acidresidue at position 313 in the SIRT6 polypeptide is encoded by codon “gcc” at positions 937 to 939 of SEQ ID NO: 5.

[0073] In certain embodiments, the N308K substitution is represented by a mutation of codon “aac” at positions 922 to 924 of SEQ ID NO: 5 into codon “aag” or codon “aaa”, preferably into codon “aag”. In other words, the N308K substitution is represented by a mutation of nucleotide “c” at positions 924 of SEQ ID NO: 5 into nucleotide “g” or nucleotide “a”, preferably into nucleotide “g”.

[0074] In certain embodiments, the A313S substitution is represented by a mutation of codon “gcc” at positions 937 to 939 of SEQ ID NO: 5 into a codon selected from a group consisting of codons “tcc”, “tct”, “tea” and “teg”, preferably codon “tcc”. In other words, the A313S substitution is represented by one or two mutation(s) selected from a group consisting of a mutation of nucleotide “g” at positions 937 of SEQ ID NO: 5 into nucleotide “t”; a mutation of nucleotide “g” at positions 937 of SEQ ID NO: 5 into nucleotide “t” and of nucleotide “c” at positions 939 of SEQ ID NO: 5 into nucleotide “t”; a mutation of nucleotide “g” at positions 937 of SEQ ID NO: 5 into nucleotide “t” and of nucleotide “c” at positions 939 of SEQ ID NO: 5 into nucleotide “a”; and a mutation of nucleotide “g” at positions 937 of SEQ ID NO: 5 into nucleotide “t” and of nucleotide “c” at positions 939 of SEQ ID NO: 5 into nucleotide “g”.

[0075] In certain embodiments, the isolated nucleic acid encoding the polypeptide being a variant of SIRT6 has at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with sequence SEQ ID NO: 6, SEQ ID NO: 7 or SEQ ID NO: 8. In some embodiments, the nucleic acid molecule is of sequence selected from the group comprising or consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8. In some embodiments, the nucleic acid molecule is of sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8.

[0076] As used herein, sequence SEQ ID NO: 6 refers to the nucleic acid sequence of the variant of SIRT6 with N308K substitution, in particular, with mutation of codon “aac” at positions 922 to 924 of SEQ ID NO: 5 into codon “aag”. In some embodiments, the isolated nucleic acid encoding the polypeptide being a variant of SIRT6 has at least 75%,80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with sequence SEQ ID NO: 6. In some embodiments, the isolated nucleic acid encoding the polypeptide being a variant of SIRT6 has the nucleic acid sequence as set forth in SEQ ID NO: 6.

[0077] As used herein, sequence SEQ ID NO: 7 refers to the nucleic acid sequence of the variant of SIRT6 with A313S substitution, in particular, with mutation of codon “gcc” at positions 922 to 924 of SEQ ID NO: 5 into codon “tcc”. In some embodiments, the isolated nucleic acid encoding the polypeptide being a variant of SIRT6 has at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with sequence SEQ ID NO: 7. In some embodiments, the isolated nucleic acid encoding the polypeptide being a variant of SIRT6 has the nucleic acid sequence as set forth in SEQ ID NO: 7.

[0078] As used herein, sequence SEQ ID NO: 8 refers to the nucleic acid sequence of the variant of SIRT6 with N308K and A313S substitutions, in particular, with mutation of codon “aac” at positions 922 to 924 of SEQ ID NO: 5 into codon “aag” and with mutation of codon “gcc” at positions 922 to 924 of SEQ ID NO: 5 into codon “tcc”. In a preferred embodiment, the isolated nucleic acid encoding the polypeptide being a variant of SIRT6 has at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with sequence SEQ ID NO: 8. In some embodiments, the isolated nucleic acid encoding the polypeptide being a variant of SIRT6 has the nucleic acid sequence as set forth in SEQ ID NO: 8.

[0079] In some embodiments, the isolated nucleic acid encoding the polypeptide being an unmodified SIRT6 has the nucleic acid sequence as set forth in SEQ ID NO: 5.

[0080] In some embodiments, the variant of SIRT6 encoded by the isolated nucleic acid molecule as defined herein may have additional mutations compared to wild type SIRT6 polypeptide. In some embodiments, the variant of SIRT6 encoded by the isolated nucleic acid molecule as defined herein may have 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more additional mutations compared to wild type SIRT6 polypeptide.

[0081] In some embodiments, the nucleic acid molecule is a nucleic single or double stranded molecule. In some embodiments, the nucleic acid molecule is a DNA molecule or a RNA molecule.

[0082] In one embodiment, the nucleic acid molecule is an RNA molecule. In some embodiments, the nucleic acid molecule is an RNA molecule selected from the list comprising messenger RNA (mRNA), transfer RNA (tRNA), ribosomal RNA (rRNA), micro-RNA (miRNA), small interfering RNA (siRNA), small nucleolar RNA (snoRNA), small nuclear RNA (snRNA), circular RNA (circ RNA), and long non-coding RNA (IncRNA). In a particular embodiment, the nucleic acid molecule is a mRNA. In some embodiments, the nucleic acid molecule is a mRNA molecule encoding a nucleic acid having a sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably SEQ ID NO: 8.

[0083] In another embodiment, the nucleic acid molecule is a DNA molecule. In some embodiments, the nucleic acid molecule is a DNA molecule selected from the list comprising genomic DNA (gDNA) or complementary DNA (cDNA) molecule. In some embodiments, the nucleic acid molecule is a DNA molecule having a sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably SEQ ID NO: 8.

[0084] In one embodiment, the isolated nucleic acid molecule does not have the nucleic acid sequence of SEQ ID NO: 5. In another embodiment, the isolated nucleic acid molecule has the nucleic acid sequence of SEQ ID NO: 5.

[0085] The present invention thus also relates to an isolated nucleic acid molecule having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably SEQ ID NO: 8, for use for preventing and / or treating a muscular disease, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle. The present invention thus also relates to an isolated nucleic acid molecule having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably SEQ ID NO: 8, for use for preventing and / or treating frailty syndrome and / or sarcopenia.

[0086] In some embodiments, the nucleic acid encoding the SIRT6 protein or variant of SIRT6 as described hereinabove is transiently expressed in the subject.

[0087] The present invention further relates to an isolated polypeptide encoded by a nucleic acid molecule as described herein, for use for preventing and / or treating a muscular disease, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle.

[0088] This invention relates to SIRT6 having at least 75% identity with sequence SEQ ID NO: 1, for the prevention and / or treatment of a muscular disease, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle. This invention also relates to an isolated polypeptide being a variant of SIRT6 having at least 75% identity with sequence SEQ ID NO: 1, the variant having at least one mutation selected from the group comprising or consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1 for the prevention and / or treatment of a muscular disease, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle. In some embodiments, the variant of SIRT6 has an amino acid sequence having from 75% to 99% identity, from 80% to 99% identity, from 85% to 99% identity, from 90% to 99% identity, or from 95% to 99% identity with SEQ ID NO: 1.

[0089] As used herein the expression “at least 75% identity” encompasses 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% and 99.5% identity. The variant of sirtuin 6 (SIRT6) has at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, therefore the isolated polypeptide does not have 100% sequence identity with SEQ ID NO: 1.

[0090] In certain embodiments, the isolated polypeptide being a variant of SIRT6 has at least 75%, 80%, 85%, 90%, 95% identity with sequence SEQ ID NO: 1 , the variant having at least one mutation selected from the group comprising or consisting of a N308K substitution and an A313S substitution with respect to sequence SEQ ID NO: 1.

[0091] In certain embodiments, the isolated polypeptide being a variant of SIRT6 has at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with sequence SEQ ID NO: 2, SEQ ID NO: 3 or SEQ ID NO: 4, preferably SEQ ID NO: 4. In someembodiments, the isolated polypeptide is of sequence selected from the group comprising or consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, preferably SEQ ID NO: 4. In some embodiments, the isolated polypeptide has an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, preferably SEQ ID NO: 4.

[0092] As used herein, the sequence SEQ ID NO: 2 refers to the amino acid sequence the variant of SIRT6 with N308K substitution. In some embodiments, the polypeptide of sequence SEQ ID NO: 2 is encoded by a nucleic acid molecule of sequence SEQ ID NO:6. In some embodiments, the isolated polypeptide has at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with sequence SEQ ID NO: 2. In some embodiments, the isolated polypeptide being a variant of SIRT6 has the amino acid sequence as set forth in SEQ ID NO: 2.

[0093] As used herein, the sequence SEQ ID NO: 3 refers to the amino acid sequence the variant of SIRT6 with A313S substitution. In some embodiments, the polypeptide of sequence SEQ ID NO: 2 is encoded by a nucleic acid molecule of sequence SEQ ID NO:7. In some embodiments, the isolated polypeptide has at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with sequence SEQ ID NO: 3. In some embodiments, the isolated polypeptide being a variant of SIRT6 has the amino acid sequence as set forth in SEQ ID NO: 3.

[0094] As used herein, the sequence SEQ ID NO: 4 refers to the amino acid sequence of the variant of SIRT6 with N308K and A313S substitutions. In some embodiments, the polypeptide of sequence SEQ ID NO: 4 is encoded by a nucleic acid molecule of sequence SEQ ID NO: 8. In a preferred embodiment, the isolated polypeptide has at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with sequence SEQ ID NO: 4. In some embodiments, the isolated polypeptide being a variant of SIRT6 has the amino acid sequence as set forth in SEQ ID NO: 4.

[0095] In certain embodiments, the polypeptide is a recombinant polypeptide. As used herein, the term “recombinant polypeptide” refers to a polypeptide encoded by anengineered nucleic acid and synthesized upon transformation of said engineered nucleic acid into a microorganism or transfection in an eukaryotic cell for synthesis purposes.

[0096] In some embodiments, the isolated polypeptide does not have the amino acid sequence of SEQ ID NO: 1.

[0097] The present invention thus also relates to an isolated polypeptide having an amino acid sequence selected from the group consisting of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, preferably SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, more preferably SEQ ID NO: 4, for use for preventing and / or treating a muscular disease, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle. The present invention also relates to an isolated polypeptide having an amino acid sequence selected from the group consisting of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, preferably SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, more preferably SEQ ID NO: 4, for use for preventing and / or treating a frailty syndrome and / or sarcopenia.

[0098] In some embodiments, the SIRT6 protein or variant of SIRT6 as described hereinabove is transiently expressed in the subject.

[0099] In some embodiments, SIRT6 or the variant of SIRT6 encoded by the isolated nucleic acid molecule as defined herein has a deacylase and / or mono-ADP ribosyl transferase (mADPr) activity.

[0100] In practice, the deacylase activity and mono-ADP ribosyl transferase (mADPr) activity may be assayed accordingly to any suitable method from the state in the art, or a method adapted therefrom. Illustratively, deacylase activity may be assayed by contacting in vitro the variant of SIRT6 with histones, in the presence of NAD+, MgCh, DTT and performing a Western blot analysis using anti-H3K9ac and anti-H3K18ac antibodies. Illustratively, mono-ADP ribosyl transferase (mADPr) activity may be assayed by contacting in vitro the variant of SIRT6 with PARP1, in the presence of ZnCh, MgCh, NAD+, DTT, salmon sperm DNA and performing a Western blot analysis using anti- PADPR antibodies.

[0101] In certain embodiments, the variant of SIRT6 has at most about 90%, preferably at most about 50%, more preferably at most about 25% deacylase activity as compared to wild type SIRT6 (of sequence SEQ ID NO: 1). Within the scope of the invention, the expression “at most about 90%” encompasses about 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 5%, 1% or less.

[0102] In some embodiments, the variant of SIRT6 has at least 100%, preferably at least about 200%, more preferably at least about 300% mono-ADP ribosyl transferase (mADPr) activity as compared to wild type SIRT6 (of sequence SEQ ID NO: 1). Within the scope of the invention, the expression “at least about 100%” encompasses about 100%, 120%, 140%, 160%, 180%, 200%, 220%, 240%, 260%, 280%, 300%, 350%, 400%, 450%, 500%, 550%, 600%, 650%, 700%, 750% or more.

[0103] In some embodiments, the variant of SIRT6 (z.e., the isolated nucleic acid as described herein, or the isolated polypeptide as described herein) upregulates genes involved in heterochromatin regulation. In some embodiments, the variant of SIRT6 upregulates genes involved in heterochromatin assembly and organization, and / or genes involved in DNA packaging.

[0104] In some embodiments, the variant of SIRT6 (z.e., the isolated nucleic acid as described herein, or the isolated polypeptide as described herein) reduces or represses the expression of transposable elements (TE). In some embodiments, the variant of SIRT6 enables the compaction and methylation of TE.

[0105] In some embodiments, the variant of SIRT6 (z.e., the isolated nucleic acid as described herein, or the isolated polypeptide as described herein) increases trimethylation at the 9thlysine residue of the histone H3 protein (H3K9me3).

[0106] In some embodiments, the variant of SIRT6 (z.e., the isolated nucleic acid as described herein, or the isolated polypeptide as described herein) facilitates heterochromatin compaction.

[0107] The present invention further relates to a vector comprising the isolated nucleic acid molecule as described herein before for use in the prevention and / or the treatment ofa muscular disease. The present invention further relates to a vector comprising an isolated nucleic acid molecule having at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with a sequence selected from the group consisting of SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, for use for preventing and / or treating a muscular disease. The present invention further relates to a vector comprising an isolated nucleic acid molecule having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably SEQ ID NO: 8, for use for preventing and / or treating a muscular disease, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle.

[0108] In some embodiments, the vector comprising the isolated nucleic acid molecule is selected from the group comprising or consisting of a bacterial artificial chromosome (BAC), a bacteriophage, a cosmid, a Doggybone DNA, a human artificial chromosome (HAC), a linear DNA, a minicircle nucleic acid, a naked DNA molecule, a messenger RNA (mRNA), a plasmid, a viral vector, an adenoviral vector, an enzymatic DNA, and an extracellular vesicle-based vector such as an exosome-based vector.

[0109] In some embodiments, the vector comprising the isolated nucleic acid molecule is selected from the group comprising or consisting of a bacterial artificial chromosome (BAC), a bacteriophage, a cosmid, a Doggybone DNA, a herpes virus vector, a human artificial chromosome (HAC), a linear DNA, a minicircle nucleic acid, a naked DNA molecule, a mRNA, a plasmid, a retroviral vector, an adeno-associated viral vector (AAV), an adenoviral vector, an enzymatic DNA, an extracellular vesicle vector such as an exosome, and an extracellular vesicle-associated AAV vector such as an exosome- associated AAV vector (exo-AAV). In some embodiments, the vector comprising the isolated nucleic acid molecule is selected from the group comprising or consisting of a bacterial artificial chromosome (BAC), a bacteriophage, a cosmid, a Doggybone DNA, a herpes virus vector, a human artificial chromosome (HAC), a minicircle nucleic acid, a plasmid, a mRNA, a retroviral vector, an adeno-associated viral vector (AAV), an adenoviral vector, an enzymatic DNA, an extracellular vesicle vector such as an exosome,and an extracellular vesicle-associated AAV vector such as an exosome-associated AAV vector (exo- AAV).

[0110] In some embodiments, the vector comprising the isolated nucleic acid molecule is selected from the group consisting of an adeno-associated viral vector (AAV), an exosome-associated AAV vector (exo-AAV), an extracellular vesicle such as an exosome, an adenoviral vector, a retroviral vector, a herpes virus vector, a plasmid, and a naked DNA molecule.

[0111] In some embodiments, the vector comprising the isolated nucleic acid molecule is a viral vector. In some embodiments, the vector comprising the isolated nucleic acid molecule is a viral vector selected from the group consisting of an adeno-associated viral vector (AAV), an adenoviral vector, a retroviral vector, and a herpes virus vector.

[0112] In some embodiments, the vector comprising the isolated nucleic acid molecule is an extracellular vesicle-based vector. In some embodiments, the vector comprising the isolated nucleic acid molecule is an exosome-based vector. In some embodiments, the vector comprising the isolated nucleic acid molecule is an extracellular vesicle-based vector selected from the group consisting of an extracellular vesicle-associated AAV vector (exo-AAV), and an extracellular vesicle. In some embodiments, the vector comprising the isolated nucleic acid molecule is an exosome-based vector selected from the group consisting of an exosome-associated AAV vector (exo-AAV), and an exosome. In some embodiments, the vector comprising the isolated nucleic acid molecule is an extracellular vesicle, preferably an exosome.

[0113] In some embodiments, the vector comprising the isolated nucleic acid molecule is selected from the group consisting of a plasmid, and a naked DNA molecule.

[0114] In some embodiments, the vector comprising the isolated nucleic acid molecule is selected from the group comprising or consisting of minicircle nucleic acid, plasmids, cosmids, bacteriophages, bacterial artificial chromosome, viral vectors, linear DNA, enzymatic DNA, and Doggybone DNA.

[0115] In some embodiments, the vector comprising the isolated nucleic acid molecule is selected from the group comprising minicircle nucleic acid, plasmids, cosmids, bacteriophages, mRNA, or a bacterial artificial chromosome or viral vectors.

[0116] In some embodiments, the vector comprising the isolated nucleic acid molecule is an adeno-associated viral vector (AAV). Non-limitative examples of AAV vectors include AAV1, AAV2, AAV4, AAV5, AAV8, and AAV9; AAV vectors may be combined. In some embodiments, the vector comprising the isolated nucleic acid molecule is an AAV2, an AAV8, or an AAV2 / 8. In some embodiments, the vector comprising the isolated nucleic acid molecule is an AAV8 vector.

[0117] In some embodiments, the vector comprising the isolated nucleic acid molecule is an extracellular vesicle-associated AAV vector. In some embodiments, the vector comprising the isolated nucleic acid molecule is an exosome-associated AAV vector (exo- AAV).

[0118] In some embodiments, the vector comprising the isolated nucleic acid molecule is an extracellular vesicle. In some embodiments, the vector comprising the isolated nucleic acid molecule is an exosome.

[0119] In some embodiments, the vector comprising the isolated nucleic acid molecule is an adenoviral vector, such as, e.g., HAd5.

[0120] In some embodiments, the vector comprising the isolated nucleic acid molecule is a viral vector, preferably a retroviral vector, optionally a lenti viral vector such as e.g., HIV. In some embodiments, the vector comprising the isolated nucleic acid molecule is a herpes virus vector.

[0121] In some embodiments, the vector comprising the isolated nucleic acid molecule is a plasmid.

[0122] In some embodiments, the vector comprising the isolated nucleic acid molecule is a naked nucleic acid molecule. In some embodiments, the vector comprising the isolated nucleic acid molecule is a naked DNA molecule. In some embodiments, the vector comprising the isolated nucleic acid molecule is a naked mRNA molecule. In someembodiments, the vector is selected from the group consisting of a plasmid, and a a naked nucleic acid molecule such as a DNA molecule or a mRNA molecule

[0123] As used herein, the term “mini circle nucleic acid” encompasses non-viral vectors that merely comprise a gene expression cassette and are free of viral and / or bacterial backbone DNA elements from standard plasmids.

[0124] As used herein, the term “plasmid” is intended to refer to a small extra-genomic DNA molecule, most commonly found as circular double stranded DNA molecules that may be used as a cloning vector in molecular biology, to make and / or modify copies of DNA fragments up to about 15 kb (i.e., 15,000 base pairs). Plasmids may also be used as expression vectors to produce large amounts of proteins of interest encoded by a nucleic acid sequence found in the plasmid downstream of a promoter sequence.

[0125] A used herein, the term “cosmid” refers to a hybrid plasmid that contains cos sequences from Lambda phage, allowing packaging of the cosmid into a phage head and subsequent infection of bacterial cell wherein the cosmid is cyclized and can replicate as a plasmid. Cosmids are typically used as cloning vector for DNA fragments ranging in size from about 32 to 52 kb.

[0126] As used herein, the term “bacterial artificial chromosome” or “BAC” refers to extra-genomic nucleic acid molecule based on a functional fertility plasmid that allows the even partition of said extra-genomic DNA molecules after division of the bacterial cell. BACs are typically used as cloning vector for DNA fragment ranging in size from about 150 to 350 kb.

[0127] As used herein, the term “enzymatic DNA” refers to a synthetic, linear, doublestranded, closed-ended DNA molecule. As used herein, the term “Doggybone DNA” refers to a minimal, linear, double stranded and covalently closed DNA construct.

[0128] In practice, the vector comprising the nucleic acid molecule encoding a variant of SIRT6 may be in the form of a plasmid, in particular resulting from the cloning of a nucleic acid of interest into a nucleic acid vector. Non-limitative suitable nucleic acid vectors are pBluescript vectors, pET vectors, pETduet vectors, pGBM vectors, pBADvectors, pUC vectors. In one embodiment, the plasmid is a low copy plasmid. In another embodiment, the plasmid is a high copy plasmid.

[0129] In some embodiments, the vector is a viral vector. In some embodiments, the viral vector is selected from a group comprising or consisting of an adenovirus; an adeno- associated virus (AAV); an exosome-associated AAV (exo-AAV); an exosome; an alphavirus; a herpesvirus; a retrovirus, such as, e.g., a lentivirus or a non-integrative lentivirus; vaccinia virus; a baculovirus; or virus like particles such as, e.g., particles derived from Hepatitis B virus, Parvoviridae, Retroviridae, Flaviviridae, Paramyxoviridae or bacteriophages. In one embodiment, the exosome comprises at least one DNA molecule, RNA molecule and / or protein, preferably the variant of SIRT6 according to the invention or a nucleic acid encoding thereof.

[0130] In some embodiments, the viral vector is selected from a group comprising or consisting of an adenovirus; an adeno-associated virus (AAV); an exosome-associated AAV (exo-AAV); an alphavirus; a herpesvirus; a retrovirus, such as, e.g., a lentivirus or a non-integrative lentivirus; vaccinia virus; a baculovirus; or virus like particles such as, e.g., particles derived from Hepatitis B virus, Parvoviridae, Retroviridae, Flaviviridae, Paramyxoviridae or bacteriophages.

[0131] In some embodiments, the viral vector of the invention is selected from the group comprising or consisting of adeno-associated viral vector (AAV), exosome-associated AAV vector (exo-AAV), exosome, adenoviral vector, retroviral vector, lentivirus and herpes virus vector.

[0132] In some embodiments, the viral vector of the invention is selected from the group comprising or consisting of adeno-associated viral vector (AAV), exosome-associated AAV vector (exo-AAV), adenoviral vector, retroviral vector, lentivirus and herpes virus vector.

[0133] In some embodiments, the viral vector of the invention is an adeno-associated viral vector (AAV), preferably an AAV serotype 2 (AAV2), an AAV serotype 8 (AAV8), an AAV serotype 5 (AAV5), or combinations thereof. In some embodiments, the viral vector of the invention is an adeno-associated viral vector (AAV) selected from the groupconsisting of AAV2, AAV8, and AAV2 / 8, preferably AAV8. In some embodiments, the viral vector of the invention is an AAV8 vector.

[0134] In certain embodiments, the vector, in particular the viral vector, is an extracellular vesicle-associated AAV vector, preferably an exo-AAV vector. As used herein, extracellular vesicle-associated AAV vector refers to a vector wherein an adeno- associated virus (AAV) vector, or parts thereof, is associated with an extracellular vesicle, preferably anexosome, wherein the AAV vector is partially fused, embedded or internalized in the extracellular vesicle. The extracellular vesicle may express specific proteins or markers, for example for targeting purposes.

[0135] In another embodiment, the viral vector is a retrovirus or lenti virus . In a preferred embodiment, the viral vector is a lentivirus

[0136] In certain embodiments, the vector is an extracellular vesicle, preferably an extracellular vesicle comprising a payload or cargo, more preferably an extracellular vesicle comprising a DNA molecule, RNA molecule and / or protein, even more preferably a variant of SIRT6 according to the invention or a nucleic acid encoding thereof. In certain embodiments, the vector is an exosome, preferably an exosome comprising a payload or cargo, more preferably an exosome comprising a DNA molecule, RNA molecule and / or protein, even more preferably a variant of SIRT6 according to the invention or a nucleic acid encoding thereof.

[0137] In some embodiments, the vector is for transient expression of SIRT6 or SIRT6 variant as defined herein. In some embodiments, the transient expression lasts from 1 hours to 1 month, from 12 hours to 2 weeks, or from 1 day to 1 week. In some embodiments, the transient expression lasts from 1 month to 36 months, from 1 month to 24 months, from 1 month to 12 months, or from 1 month to 6 months.

[0138] The present invention therefore also pertains to an adeno-associated viral vector (AAV), preferably an AAV8 vector, comprising the isolated nucleic acid molecule as described herein before for use in the prevention and / or the treatment of a muscular disease in a subject in need thereof, wherein the isolated nucleic acid molecule is transiently expressed in the subject. The present invention further relates to an adeno-associated viral vector (AAV), preferably an AAV8 vector, comprising an isolated nucleic acid molecule having at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with a sequence selected from the group consisting of SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, for use for preventing and / or treating a muscular disease in a subject in need thereof, wherein the isolated nucleic acid molecule is transiently expressed in the subject. The present invention further relates to an adeno-associated viral vector (AAV), preferably an AAV8 vector, comprising an isolated nucleic acid molecule having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably SEQ ID NO: 8, for use for preventing and / or treating a muscular disease in a subject in need thereof, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle, wherein the isolated nucleic acid molecule is transiently expressed in the subject.

[0139] In certain embodiments, the vector, in particular the viral vector, does not cross the blood-brain barrier. In some alternative embodiments, the vector, in particular viral vector, crosses the blood-brain barrier.

[0140] In some embodiments, the vector, in particular the viral vector, comprises a promoter sequence suitable for gene expression in mammalian individuals, preferably in human individuals.

[0141] Non-limitative examples of promoter sequence suitable for gene expression in mammalian individuals, preferably in human individuals, include CMV (human cytomegalovirus) promoter, EFla (human elongation factor 1 alpha) promoter, SV40 (Simian vacuolating virus 40) promoter, PGK1 (phosphoglycerate kinase) promoter, UbC (human ubiquitin C) promoter, ColA2 promoter, Coll Al promoter, Col3Al promoter, and the like.

[0142] In certain embodiments, the promoter sequence is preferably the EFla promoter, or a part thereof.

[0143] In some embodiments, the vector, in particular the viral vector, further comprises a nucleic acid sequence that facilitates the nuclear localization of the polypeptide encoded by the nucleic acid molecule according to the invention into a target recipient cell. In practice, these nuclear localization signal (NLS) have been abundantly discussed in the state of the art.

[0144] The present invention further relates to a cell expressing the nucleic acid or polypeptide as described herein, the cell being preferably transfected with the nucleic acid molecule, or the vector, for use in the prevention and / or the treatment of a muscular disease. The present invention further relates to a cell expressing a nucleic acid molecule having at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with a sequence selected from the group consisting of SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8„ and / or expressing a polypeptide having at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with a sequence selected from the group consisting of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, preferably selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, for use for preventing and / or treating a muscular disease, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle.

[0145] As used herein, “expressing a nucleic acid molecule” means that the cell comprises and translates at least one nucleic acid molecule as described herein. As used herein, “expressing a polypeptide” means that the cell comprises and translates at least one polypeptide as described herein.

[0146] In certain embodiments, the cell is a eukaryote cell, preferably an animal cells, more preferably a mammalian cell. As used herein “mammalian cell” includes nonhuman mammalian cells and human cells. In some embodiments, the cell is a human cell.

[0147] Non-limitative examples of cells include nerve cells, bone cells, breast cells, red blood cells, white blood cells, cartilage cells, epithelial cells, endothelial cells, skin cells, progenitor cells and in particular muscle progenitor cells, muscle cells, bladder cells,kidney cells, liver cells, prostate cells, cervix cells, ovarian cells, pulmonary cells, retinal cells, conjunctival cells, corneal cells, fat cells, and the like.

[0148] In some embodiments, the cell is a progenitor cell or a stem cell. In some embodiments, the cell is a progenitor cell. In some embodiments, the cell is a stem cell.

[0149] In some embodiments, the cell is a muscle progenitor cell, a muscle stem cell, or a muscle cell. In some embodiments, the progenitor cell is a muscle progenitor cell, preferably a skeletal muscle progenitor cell. In some embodiments, the stem cell is a muscle stem cell, preferably a skeletal muscle stem cell. In some embodiments, the cell is a muscle cell, preferably a skeletal muscle cell.

[0150] In some embodiments, the cell is a skeletal muscle cell or a skeletal muscle progenitor cell (SMPC). In some embodiments, the cell is a skeletal muscle progenitor cell. In some embodiments, the cell is a skeletal muscle cell.

[0151] It is to be understood that the cell according to the invention has been transfected with an isolated nucleic acid molecule according to the invention, or transduced with an isolated nucleic acid molecule according to the invention, or contacted with the vector or the suspension containing the nucleic acid molecule according to the invention. Therefore, the cell contains the nucleic acid molecules either integrated or not in its genome. In practice, because the vector is an expression system, the nucleic acid molecule encoding the variant of SIRT6 is present within the cell in a form allowing its expression and its final location, i.e., the cell nucleus and cytoplasm.

[0152] The present invention thus further relates to a cell, preferably a progenitor cell, more preferably a muscle progenitor cell, expressing a nucleic acid molecule having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably SEQ ID NO: 8, for use for preventing and / or treating a muscular disease, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle. The present invention also relates to a cell, preferably a progenitor cell, more preferably a muscle progenitor cell, expressing a polypeptide having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, preferably SEQ ID NO: 4, for use forpreventing and / or treating a muscular disease, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle.

[0153] The present invention thus further relates to a cell, preferably a progenitor cell, more preferably a muscle progenitor cell, expressing a nucleic acid molecule having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably SEQ ID NO: 8, for use for preventing and / or treating frailty syndrome and / or sarcopenia. The present invention also relates to a cell, preferably a progenitor cell, more preferably a muscle progenitor cell, expressing a polypeptide having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, preferably SEQ ID NO: 4, for use for preventing and / or treating frailty syndrome and / or sarcopenia.

[0154] The present invention further relates to a composition comprising (i) an isolated nucleic acid molecule as described herein, or an isolated polypeptide as described herein, or a vector as described herein, for use for preventing and / or treating a muscular disease, preferably wherein said composition is a suspension.

[0155] The present invention further relates to a pharmaceutical composition comprising (i) an isolated nucleic acid molecule as described herein, or an isolated polypeptide as described herein, or a vector as described herein, and (ii) a pharmaceutically acceptable excipient, for use in the prevention and / or treatment of a muscular disease. The present invention further relates to a pharmaceutical composition comprising (i) an isolated nucleic acid molecule as described herein, or an isolated polypeptide as described herein, or a vector as described herein, and (ii) a pharmaceutically acceptable excipient, for use for preventing and / or treating a muscular disease. The present invention further relates to a pharmaceutical composition consisting essentially of an isolated nucleic acid molecule as described herein, or an isolated polypeptide as described herein, or a vector as described herein, for use in the prevention and / or treatment of a muscular disease. As used herein, “consisting essentially of’ means that the pharmaceutical composition may or may not comprise other ingredients, but the “essential” or sole active ingredient is theisolated nucleic acid molecule as described herein, or the isolated polypeptide as described herein, or the vector as described herein.

[0156] In certain embodiments, the isolated nucleic acid molecule as described herein, or the isolated polypeptide as described herein, or the vector as described herein, comprised in the pharmaceutical composition, is the only active ingredient of the pharmaceutical composition.

[0157] The present invention further relates to a pharmaceutical composition comprising a nucleic acid molecule having at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with sequence SEQ ID NO: 6, SEQ ID NO: 7 or SEQ ID NO: 8, and / or expressing a polypeptide having at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with sequence SEQ ID NO: 2, SEQ ID NO: 3 or SEQ ID NO: 4, and (ii) a pharmaceutically acceptable excipient, for use for preventing and / or treating a muscular disease, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle.

[0158] As used herein, a suitable “pharmaceutically acceptable excipient” or “pharmaceutically acceptable carrier” includes any and all conventional solvents, nontoxic solid, semi-solid, or liquid fillers, dispersion media, other fillers, solid carriers, aqueous solutions, diluents, encapsulating materials, coatings, antibacterial and antifungal agents, isotonic and absorption delaying agents, formulations, and the like, i.e., molecular entities and compositions that do not cause adverse, allergic, or other harmful reactions when administered to a mammal, in particular humans. In certain embodiments, suitable pharmaceutically acceptable excipients or carriers may include, water, saline, phosphate buffered saline, dextrose, glycerol, ethanol and a mixture thereof. In some embodiments, pharmaceutically acceptable excipients or carriers may further comprise minor amounts of auxiliary substances such as wetting or emulsifying agents, preservatives or buffers, which enhance the shelf life or effectiveness of the cells. The preparation and use of pharmaceutically acceptable excipients or carriers are well known in the art. The form of the pharmaceutically acceptable excipients or carriers, route of administration, dosage, and regimen depend on the condition being treated, severity of the illness, and the patient's age, weight, and sex, among other factors. In someembodiments, the carrier may be water or saline (e.g., physiological saline), which will be sterile and pyrogen free. Suitable excipients include mannitol, dextrose, lactose, starch, magnesium stearate, sodium saccharine, cellulose, magnesium carbonate, and the like. Acceptable excipients or carriers for therapeutic use are well known in the pharmaceutical art. The choice of a suitable pharmaceutical carrier, solvent, excipient or diluent can be made with regard to the intended route of administration and standard pharmaceutical practice. The pharmaceutical compositions may comprise as, or in addition to, the carrier, excipient, solvent or diluent any suitable binder, lubricant, suspending agent, coating agent, or solubilizing agent. Preservatives, stabilizers, dyes and even flavoring agents may be provided in the pharmaceutical composition. The formulations may conveniently be presented in unit dosage form and may be prepared by any of the methods and the good practices well known in the art of pharmacy. Such methods include the step of bringing into association the polypeptide with the carrier which constitutes one or more accessory ingredients.

[0159] For the particular purpose of human administration, the pharmaceutical compositions should meet sterility, pyrogenicity, general safety and purity standards as required by regulatory offices, such as, for example, the Food and Drugs Administration (FDA) Office or the European Medicines Agency (EMA).

[0160] The present invention thus further relates to a pharmaceutical composition comprising a nucleic acid molecule having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably SEQ ID NO: 8, for use for preventing and / or treating a muscular disease, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle. The present invention also relates to a pharmaceutical composition comprising a polypeptide having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, preferably SEQ ID NO: 4, for use for preventing and / or treating a muscular disease, preferably a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle.

[0161] The present invention thus further relates to a pharmaceutical composition comprising a nucleic acid molecule having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, more preferably SEQ ID NO: 8, for use for preventing and / or treating frailty syndrome and / or sarcopenia. The present invention also relates to a pharmaceutical composition comprising a polypeptide having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, preferably SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, more preferably SEQ ID NO: 4, for use for preventing and / or treating frailty syndrome and / or sarcopenia.

[0162] The present invention further relates to a suspension comprising a vector for use in the prevention and / or the treatment of a muscular disease.

[0163] In one aspect, the invention relates to a suspension comprising a vector according to the invention.

[0164] In some embodiments, the suspension further comprises a fluid including one or more ingredients selected from the group consisting of water, saline, phosphate buffered saline, dextrose, glycerol, ethanol and a combination thereof.

[0165] In certain embodiment, the suspension is formulated for intravenous infusion. In practice, the suspension formulated for intravenous infusion may comprise saline (e.g., 0.9% NaCl); lactated Ringers; 5% dextrose; a colloid, such as, e.g., albumin; the like; and any combination thereof

[0166] As used herein, “muscular disease” or “muscle disease” refers to a broad category of disorders that affect the structure (including mass) and function (including endocrine, paracrine and autocrine function) of muscles and in particular skeletal muscles. Muscular diseases may be genetic, inflammatory, metabolic, and / or neurodegenerative in nature and often result in muscle weakness, atrophy, pain, alteration of endocrine muscle function, and impaired mobility.

[0167] Non-limitative examples of muscular diseases include geriatric muscular diseases, muscular dystrophies, inflammatory myopathies, metabolic muscular diseases, congenital myopathies, mitochondrial myopathies, myasthenic syndromes, myotonic disorders, channelopathies, toxic myopathies, and endocrine myopathies, preferably geriatric muscular diseases. Illustratively, and not limitatively, these types of muscular diseases may include acromegalic myopathy, becker muscular dystrophy, central core disease, centronuclear myopathy, congenital muscular dystrophy, congenital myasthenic syndromes, congenital myopathies, cushing's myopathy, dermatomyositis, distal muscular dystrophy, duchenne muscular dystrophy, emery-dreifuss muscular dystrophy, endocrine myopathies, facioscapulohumeral muscular dystrophy, fibromyalgia, fraily syndrome, glycogen storage diseases, hyperkalemic periodic paralysis, hyperthyroid myopathy, hypokalemic periodic paralysis, hypothyroid myopathy, inclusion body myositis, lambert-eaton myasthenic syndrome, limb-girdle muscular dystrophy, lipid storage diseases, malignant hyperthermia, metabolic myopathies, mitochondrial myopathies, myasthenia gravis, myotonia congenita, myotonic dystrophy, myotubular myopathy, necrotizing autoimmune myopathy, nemaline myopathy, oculopharyngeal muscular dystrophy, paramyotonia congenita, periodic paralysis, polymyositis, rhabdomyolysis, sarcopenia, stiff person syndrome, toxic myopathies, and myositis ossificans.

[0168] In one embodiment, the muscular disease is a geriatric muscular disease. In some embodiments, the muscular disease is a geriatric muscular disease selected from the group consisting of sarcopenia, inclusion body myositis, polymyositis, dermatomyositis, rhabdomyolysis, fibromyalgia, hyperthyroid myopathy, hypothyroid myopathy, Cushing’s myopathy, acromegalic myopathy, steroid-induced myopathy, diabetic myopathy, critical illness myopathy, statin-induced myopathy, mitochondrial myopathies, and amyotrophic lateral sclerosis (ALS).

[0169] In some embodiments, the subject to be treated is at least 60 years old, at least 65 years old, at least 70 years old, at least 75 years old, at least 80 years old, at least 85 years old, or at least 90 years old.

[0170] In one embodiment, the muscular disease is a not a geriatric muscular disease. In some embodiments, the subject to be treated is less than 60 years old, less than 55 years old, less than 50 years old, less than 45 years old, or less than 40 years old.

[0171] In some embodiments, the muscular disease is selected from the group consisting of frailty syndrome and sarcopenia.

[0172] As used herein, “sarcopenia” refers to a clinical syndrome characterized by the progressive and generalized loss of skeletal muscle mass, strength, and function, as well as paracrine, endocrine, and / or autocrine, typically but not exclusively associated with aging. It is diagnosed based on low muscle mass and either low muscle strength, altered endocrine function of the muscle, or low physical performance, leading to an increased risk of physical disability, poor quality of life, and death.

[0173] As used herein, “frailty syndrome” refers to a clinical condition often but not exclusively occurring in older adults, characterized by a decrease in physiological reserve and an increased vulnerability to stressors. It is marked by symptoms such as unintentional weight loss, in particular muscle mass loss, exhaustion, weakness, slow walking speed, and low physical activity. Frailty increases the risk of adverse health outcomes, including falls, hospitalization, disability, and mortality.

[0174] In some embodiments, the muscular disease is frailty syndrome.

[0175] In some embodiments, the muscular disease is sarcopenia. In some embodiments, the muscular disease is primary sarcopenia, secondary sarcopenia, acute sarcopenia, chronic sarcopenia.

[0176] In some embodiments, the muscular disease is characterized by loss of muscle mass and alteration of the endocrine function of the muscle. In some embodiments, muscular disease is a geriatric muscular disease, more preferably frailty syndrome and / or sarcopenia.

[0177] In some preferred embodiments, the muscular disease is characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle. In some preferredembodiments, the muscular disease is characterized by loss of muscle mass and alteration of the endocrine function of the muscle.

[0178] In some embodiments, the muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle is selected from the group consisting of sarcopenia; cachexia including cancer cachexia; neuromuscular diseases such as Amyotrophic Lateral Sclerosis or Charcot-Marie-Tooth disease; myopathies including type 2 diabetes-associated myopathy, chronic heart failure-associated myopathy, chronic kidney disease-associated myopathy, glucocorticoid-induced myopathy, or myotonic dystrophy; chronic obstructive pulmonary disease (COPD)- associated muscle wasting; rheumatoid arthritis-associated muscle wasting; and disuse atrophy.

[0179] In some embodiments, the muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle is selected from the group consisting of sarcopenia, cancer cachexia, neuromuscular diseases such as Amyotrophic Lateral Sclerosis and Charcot-Marie-Tooth disease, and myopathies.

[0180] In some embodiments, the muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle is selected from the group consisting of sarcopenia, cachexia, chronic obstructive pulmonary disease (COPD)- associated muscle wasting, chronic kidney disease-associated myopathy, chronic heart failure-associated myopathy, disuse atrophy, glucocorticoid-induced myopathy, myotonic dystrophy, rheumatoid arthritis-associated muscle wasting, and type 2 diabetes- associated myopathy.

[0181] In some embodiments, the muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle is sarcopenia.

[0182] In some embodiments, the muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle is cachexia. In some embodiments, the muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle is cancer cachexia.

[0183] In some embodiments, the muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle is a neuromuscular disease. In some embodiments, the muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle is Amyotrophic Lateral Sclerosis or Charcot-Marie-Tooth disease.

[0184] In some embodiments, the muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle is a myopathy. Non-limitative examples of myopathies include muscular dystrophies, myotonic dystrophy, congenital myopathies, mitochondrial myopathies, inflammatory myopathies like polymyositis and dermatomyositis, metabolic myopathies including glycogen storage diseases and lipid storage diseases, toxic myopathies caused by drugs or toxins, endocrine myopathies related to thyroid or adrenal disorders, and neuromuscular junction disorders like myasthenia gravis.

[0185] Accordingly, the invention also relates to an isolated nucleic acid molecule having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, preferably SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8, more preferably SEQ ID NO: 8, or an isolated polypeptide having an amino acid sequence selected from the group consisting of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, preferably SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4, more preferably SEQ ID NO: 4, or a vector comprising thereof, or a pharmaceutical composition comprising said isolated nucleic acid molecule or said isolated polypeptide or said vector, or a cell selected from the group consisting of muscle cell, progenitor cell or muscular progenitor cell, comprising said isolated nucleic acid molecule or said isolated polypeptide or said vector, for use for treating and / or preventing a muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle selected from the group consisting of sarcopenia, cancer cachexia, neuromuscular diseases such as Amyotrophic Lateral Sclerosis and Charcot-Marie-Tooth disease, and myopathies.

[0186] In some embodiments, the muscular disease is characterized by a loss or decrease of muscle mass of 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%,15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or more, compared to a substantially healthy subject. As used herein, a “substantially healthy subject” or “healthy subject” refers to a subject that was not diagnosed with a muscular disease, and / or a subject that has no loss of muscle mass and / or alteration of the endocrine function of the muscles.

[0187] It is known in the art that the muscle, in particular the skeletal muscle, has paracrine, endocrine, and / or autocrine roles upon various conditions. Muscle cells (z.e., myocytes) secrete proteins associated with these processes, that are called “myokines”. Non-limitative examples of myokines include osteonectin (SPARC), cathepsin B, brain- derived neurotrophic factor (BDNF), irisin, apelin, myostatin (GDF-8), myonectin (CTRP15), decorin, peroxisome proliferator activated receptor gamma 1 -alpha coactivator (PGC-1 alpha), leukemia inhibitory factor (LIF), oncostatin M, interleukin 6 (IL-6), interleukin 15 (IL- 15), fibroblast growth factor 21 (FGF21), insulin-like growth factor-1 (IGF-1), BAIBA (P-aminoisobutyric acid), meteorin-like (METRNL), angiopoietin-like 4 (ANPTL4), chemokine (C-C motif) ligand 2 (CCL2), chitinase-3-like protein 1 (CHI3L1), connective tissue growth factor (CTGF), and follistatin. Certain cytokines or chemokines are also associated with muscle functions such as, illustratively, IL 10 (Interleukin 10), IL 8, MCP-1, IL 1 receptor antagonist (IL- Ira), macrophage inflammatory protein a (MIP-la), and MIP-ip.

[0188] Hence, in some embodiments, the muscular disease is characterized by an altered expression and / or function of one or more myokine, preferably a myokine selected from the group consisting of osteonectin (SPARC), cathepsin B, brain-derived neurotrophic factor (BDNF), irisin, apelin, myostatin (GDF-8), myonectin (CTRP15), decorin, peroxisome proliferator activated receptor gamma 1 -alpha coactivator (PGC-1 alpha), leukemia inhibitory factor (LIF), oncostatin M, interleukin 6 (IL-6), interleukin 15 (IL- 15), fibroblast growth factor 21 (FGF21), insulin-like growth factor- 1 (IGF-1), BAIBA (P-aminoisobutyric acid), meteorin-like (METRNL), angiopoietin-like 4 (ANPTL4), chemokine (C-C motif) ligand 2 (CCL2), chitinase-3-like protein 1 (CHI3L1), connective tissue growth factor (CTGF), and follistatin. In some embodiments, the muscular diseaseis characterized by an altered expression and / or function of one or more myokine selected from the group consisting of myostatin (GDF-8), interleukin-6 (IL-6), interleukin- 15 (IL- 15), follistatin, irisin, decorin, insulin-like growth factor- 1 (IGF-1), and brain-derived neurotrophic factor (BDNF). In some embodiments, the muscular disease is characterized by an altered expression and / or function of one or more myokine selected from the group consisting of myostatin, IL-6, IL-15, IGF, and FGF-21. In some embodiments, the muscular disease is characterized by an altered expression and / or function of myostatin. In some embodiments, the muscular disease is characterized by an altered expression and / or function of IL-6 In some embodiments, the muscular disease is characterized by an altered expression and / or function of IL-15 In some embodiments, the muscular disease is characterized by an altered expression and / or function of IGF. In some embodiments, the muscular disease is characterized by an altered expression and / or function of FGF-21.

[0189] In some embodiments, the muscular disease is characterized by an expression of at least one myokine decreased by 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or more, compared to a healthy subject, preferably wherein the at least one myokine is selected from the group consisting of osteonectin (SPARC), cathepsin B, brain-derived neurotrophic factor (BDNF), irisin, apelin, myostatin (GDF-8), myonectin (CTRP15), decorin, peroxisome proliferator activated receptor gamma 1 -alpha coactivator (PGC-1 alpha), leukemia inhibitory factor (LIF), oncostatin M, interleukin 6 (IL-6), interleukin 15 (IL- 15), fibroblast growth factor 21 (FGF21), insulin-like growth factor-1 (IGF-1), BAIBA (P-aminoisobutyric acid), meteorin-like (METRNL), angiopoietin-like 4 (ANPTL4), chemokine (C-C motif) ligand 2 (CCL2), chitinase-3-like protein 1 (CHI3L1), connective tissue growth factor (CTGF), and follistatin. In some embodiments, the muscular disease is characterized by an expression of at least one myokine decreased by 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%,or more, compared to a healthy subject, preferably wherein the at least one myokine is selected from the group consisting of myostatin, IL-6, IL-15, IGF, and FGF-21.

[0190] In some embodiments, the muscular disease is characterized by a function of at least one myokine decreased by 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or more, compared to a healthy subject, preferably wherein the at least one myokine is selected from the group consisting of osteonectin (SPARC), cathepsin B, brain-derived neurotrophic factor (BDNF), irisin, apelin, myostatin (GDF-8), myonectin (CTRP15), decorin, peroxisome proliferator activated receptor gamma 1 -alpha coactivator (PGC-1 alpha), leukemia inhibitory factor (LIF), oncostatin M, interleukin 6 (IL-6), interleukin 15 (IL-15), fibroblast growth factor 21 (FGF21), insulin-like growth factor-1 (IGF-1), BAIBA (P-aminoisobutyric acid), meteorin-like (METRNL), angiopoietin-like 4 (ANPTL4), chemokine (C-C motif) ligand 2 (CCL2), chitinase-3-like protein 1 (CHI3L1), connective tissue growth factor (CTGF), and follistatin. In some embodiments, the muscular disease is characterized by a function of at least one myokine decreased by 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or more, compared to a healthy subject, preferably wherein the at least one myokine is selected from the group consisting of myostatin, IL-6, IL- 15, IGF, and FGF-21.

[0191] Myokines play a crucial role in the adaptation of skeletal muscle by serving as paracrine regulators that influence blood vessel formation, insulin sensitivity, body weight gain, inflammation and in particular chronic inflammation, inhibition of tumor growth, cognitive enhancement, extracellular matrix maintenance, metabolism, and muscle growth.

[0192] In some embodiments, the muscular disease is characterized by loss of muscle mass and / or one or more of the following: inflammation, altered blood vessel formation or angiogenesis, decreased insulin sensitivity, extracellular matrix defects, cognitive impairment, or any combination thereof.

[0193] Accordingly, another aspect of the present invention relates to an isolated polypeptide comprising an amino acid sequence having at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with sequence SEQ ID NO: 2, SEQ ID NO: 3 or SEQ ID NO: 4, preferably having the amino acid sequence as set forth in SEQ ID NO: 2, SEQ ID NO: 3 or SEQ ID NO: 4, more preferably having the amino acid sequence as set forth in SEQ ID NO: 4, wherein the amino acid sequence of said isolated polypeptide is not SEQ ID NO: 1; or a nucleic acid encoding thereof; or a vector comprising a nucleic acid encoding thereof; or cell comprising thereof; or a pharmaceutical composition comprising thereof; for use for treating and / or preventing a disease associated with altered endocrine function of the muscle. In some embodiments, the disease associated with altered endocrine function of the muscle is selected from the group consisting of angiogenesis defect-related diseases, insulin sensitivity-related diseases, inflammatory conditions and in particular chronic inflammatory conditions, cancer, cognitive diseases, and metabolic diseases. In some embodiments, the disease associated with altered endocrine function of the muscle is an inflammatory condition, preferably a chronic inflammatory condition or neuroinflammation. In some embodiments, the disease associated with altered endocrine function of the muscle is cancer. In some embodiments, the disease associated with altered endocrine function of the muscle is an angiogenesis defect-related disease.

[0194] Accordingly, the present invention also pertains to to an isolated polypeptide comprising an amino acid sequence having at least 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% identity with SEQ ID NO: 1; or a nucleic acid encoding thereof; or a vector comprising a nucleic acid encoding thereof; or cell comprising thereof; or a pharmaceutical composition comprising thereof; for use for treating and / or preventing a disease associated with altered endocrine function of the muscle. In some embodiments, the disease associated with altered endocrine function of the muscle is selected from the group consisting of angiogenesis defect-related diseases, insulin sensitivity-related diseases, inflammatory conditions and in particular chronic inflammatory conditions, cancer, cognitive diseases, and metabolic diseases. In some embodiments, the disease associated with altered endocrine function of the muscle is an inflammatory condition, preferably a chronic inflammatory condition or neuroinflammation. In someembodiments, the disease associated with altered endocrine function of the muscle is cancer. In some embodiments, the disease associated with altered endocrine function of the muscle is an angiogenesis defect-related disease.

[0195] In some embodiments, the nucleic acid molecule, the polypeptide, the vector, the suspension, or the pharmaceutical composition according to the invention is to be administered to an individual in need thereof by any suitable route, i.e., by a dermal administration, by an oral administration, a topical administration or a parenteral administration, e.g., by injection, including a sub-cutaneous administration, a venous administration, an arterial administration, in intra-muscular administration, an intraocular administration and an intra-auricular administration.

[0196] In certain embodiments, the nucleic acid molecule, the polypeptide, the vector, the suspension, or the pharmaceutical composition according to the invention is to be administered to an individual in need thereof by a dermal administration. In certain embodiments, the nucleic acid molecule, the polypeptide, the vector, the suspension, or the pharmaceutical composition according to the invention is associated with a composition enabling and / or facilitating dermal administration, e.g., by increasing dermal tropism or by increasing dermal barrier penetration. In some embodiments, the dermal administration enables a prolonged liberation of the nucleic acid molecule, the polypeptide, the vector, the suspension, or the pharmaceutical composition according to the invention.

[0197] In certain embodiments, the nucleic acid molecule, the polypeptide, the vector, the suspension, or the pharmaceutical composition according to the invention is to be administered to an individual in need thereof by an intravenous administration, in particular by intravenous infusion or intravenous injection.

[0198] Within the scope of the instant invention, the therapeutically effective amount of the nucleic acid molecule, the polypeptide, the vector, the suspension, or the pharmaceutical composition according to the invention, to be administered may be determined by a physician or an authorized person skilled in the art and can be suitably adapted within the time course of the treatment.

[0199] In certain embodiments, the therapeutically effective amount to be administered may depend upon a variety of parameters, including the material selected for administration, whether the administration is in single or multiple doses, and the individual’s parameters including age, physical conditions, size, weight, gender, and the severity of the muscular disease to be treated.

[0200] In certain embodiments, a therapeutically effective amount of the isolated polypeptide, or the pharmaceutical composition comprising the isolated polypeptide according to the invention, agent may range from about 0.001 mg to about 3,000 mg, per dosage unit, preferably from about 0.05 mg to about 100 mg, per dosage unit.

[0201] Within the scope of the instant invention, the expression “from about 0.001 mg to about 3,000 mg” includes, from about 0.001 mg, 0.002 mg, 0.003 mg, 0.004 mg, 0.005 mg, 0.006 mg, 0.007 mg, 0.008 mg, 0.009 mg, 0.01 mg, 0.02 mg, 0.03 mg, 0.04 mg, 0.05 10 mg, 0.06 mg, 0.07 mg, 0.08 mg, 0.09 mg, 0.1 mg, 0.2 mg, 0.3 mg, 0.4 mg, 0.5 mg, 0.6 mg, 0.7 mg, 0.8 mg, 0.9 mg, 1 mg, 2 mg, 3 mg, 4 mg, 5 mg, 6 mg, 7 mg, 8 mg, 9 mg, 10 mg, 20 mg, 30 mg, 40 mg, 50 mg, 60 mg, 70 mg, 80 mg, 90 mg, 100 mg, 150 mg, 200 mg, 250 mg, 300 mg, 350 mg, 400 mg, 450 mg, 500 mg, 550 mg, 600 mg, 650 mg, 700 mg, 750 mg, 800 mg, 850 mg, 900 mg, 950 mg, 1,000 mg, 1,100 mg, 1,150 mg, 1,200 15 mg, 1,250 mg, 1,300 mg, 1,350 mg, 1,400 mg, 1,450 mg, 1,500 mg, 1,550 mg, 1,600 mg, 1,650 mg, 1,700 mg, 1,750 mg, 1,800 mg, 1,850 mg, 1,900 mg, 1,950 mg, 2,000 mg,2,100 mg, 2,150 mg, 2,200 mg, 2,250 mg, 2,300 mg, 2,350 mg, 2,400 mg, 2,450 mg,2,500 mg, 2,550 mg, 2,600 mg, 2,650 mg, 2,700 mg, 2,750 mg, 2,800 mg, 2,850 mg,2,900 mg, 2,950 mg and 3,000 mg per dosage unit.

[0202] In certain embodiments, the isolated polypeptide or the pharmaceutical composition comprising the isolated polypeptide according to the invention, may be at dosage levels sufficient to deliver from about 0.001 mg / kg to about 100 mg / kg, from about 0.01 mg / kg to about 50 mg / kg, preferably from about 0.1 mg / kg to about 40 mg / kg, preferably from about 0.5 mg / kg to about 30 mg / kg, from about 0.01 mg / kg to about 25 mg / kg, from about 0.1 mg / kg to about 10 mg / kg, and more preferably from about 1 mg / kg to about 25 mg / kg, of subject body weight per day. Within the scope of the instant invention, the expression “from about 0.001 mg / kg to about 100 mg / kg” includes about0.001 mg / kg, 0.002 mg / kg, 0.003 mg / kg, 0.004 mg / kg, 0.005 mg / kg, 0.006 mg / kg, 0.007 mg / kg, 0.008 mg / kg, 0.009 mg / kg, 0.01 mg / kg, 0.02 mg / kg, 0.03 mg / kg, 0.04 mg / kg, 30 0.05 mg / kg, 0.06 mg / kg, 0.07 mg / kg, 0.08 mg / kg, 0.09 mg / kg, 0.1 mg / kg, 0.2 mg / kg, 0.3 mg / kg, 0.4 mg / kg, 0.5 mg / kg, 0.6 mg / kg, 0.7 mg / kg, 0.8 mg / kg, 0.9 mg / kg, 1 mg / kg, 2 mg / kg, 3 mg / kg, 4 mg / kg, 5 mg / kg, 6 mg / kg, 7 mg / kg, 8 mg / kg, 9 mg / kg, 10 mg / kg, 20 mg / kg, 30 mg / kg, 40 mg / kg, 50 mg / kg, 60 mg / kg, 70 mg / kg, 80 mg / kg, 90 mg / kg and100 mg / kg.

[0203] In some embodiments, the therapeutically efficient amount of the isolated nucleic acid molecule, vector, or pharmaceutical composition according to the invention is ranging from about 101to about 1015copies per ml. In practice, a therapeutically efficient amount includes about 101, 5X101, 102, 5xl02, 103, 5xl03, 104, 5xl04, 105, 5xl05, 106, 5xl06, 107, 5xl07, 108, 5xl08, 109, 5xl09, 1010, 5xl010, 1011, 5xl0n, 1012, 5xl012, 1013, 5xl013, 1014, 5xl014and 1015copies per ml. In certain embodiments, the therapeutically efficient amount is from about 101to about 1015copies per cm3, which includes about 101, 5X101, 102, 5xl02, 103, 5xl03, 104, 5xl04, 105, 5xl05, 106, 5xl06, 107, 5xl07, 108, 5xl08, 109, 5xl09, IO10, 5xlO10, 1011, 5xlOn, 1012, 5xl012, 1013, 5xl013, 1014, 5xl014and 1015per cm3. In some embodiments, the therapeutically efficient amount is from about101to about 1015copies per dose, which includes about 101, 5X101, 102, 5xl02, 103, 5xl03, 104, 5xl04, 105, 5xl05, 106, 5xl06, 107, 5xl07, 108, 5xl08, 109, 5xl09, IO10, 5xlO10, 1011, 5xlOn, 1012, 5xl012, 1013, 5xl013, 1014, 5xl014and 1015copies per dose.

[0204] In certain embodiments, the isolated nucleic acid molecule, isolated polypeptide, vector, suspension, or pharmaceutical composition according to the instant invention is to be co-administered, or sequentially administered, with a drug suitable for preventing and / or treating a muscular disease as described herein.

[0205] As used herein, the term “co-administered” refers to a simultaneous administration of the active principles. As used herein, the term “sequentially administered” refers to an administration of a first active principle before or after the administration of a second active principle.

[0206] The invention also relates to the use of an isolated nucleic acid molecule, or an isolated polypeptide, or a vector according to the instant invention, for the preparation or the manufacture of a medicament for the prevention and / or the treatment of a muscular disease. The present invention also relates to the use of an isolated nucleic acid molecule encoding sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1; or an isolated sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1; or a pharmaceutical composition comprising the same; for the manufacture of a medicament for preventing and / or treating a muscular disease. The present invention also relates to the use of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or an isolated polypeptide being a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4; or a pharmaceutical composition comprising the same; for the manufacture of a medicament for preventing and / or treating a muscular disease.

[0207] In some embodiments, the muscular disease is a geriatric muscular disease.

[0208] In some embodiments, the muscular disease is selected from the group consisting of frailty syndrome and sarcopenia.

[0209] In some embodiments, the muscular disease is frailty syndrome. Therefore the present invention also relates to the use of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the groupconsisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or an isolated polypeptide being a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4; or a pharmaceutical composition comprising the same; for the manufacture of a medicament for preventing and / or treating frailty syndrome.

[0210] In some embodiments, the muscular disease is sarcopenia. Therefore the present invention also relates to the use of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or an isolated polypeptide being a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4; or a pharmaceutical composition comprising the same; for the manufacture of a medicament for preventing and / or treating sarcopenia.

[0211] In some embodiments, the muscular disease is characterized by loss of muscle mass and alteration of the endocrine function of the muscle. Therefore the present invention also relates to the use of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or an isolated polypeptidebeing a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4; or a pharmaceutical composition comprising the same; for the manufacture of a of a medicament for preventing and / or treating muscular disease characterized by an expression and / or function of at least one myokine decreased by 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or more, compared to a healthy subject, preferably wherein the at least one myokine is selected from the group consisting of osteonectin (SPARC), cathepsin B, brain-derived neurotrophic factor (BDNF), irisin, apelin, myostatin (GDF-8), myonectin (CTRP15), decorin, peroxisome proliferator activated receptor gamma 1-alpha coactivator (PGC-1 alpha), leukemia inhibitory factor (LIF), oncostatin M, interleukin 6 (IL-6), interleukin 15 (IL- 15), fibroblast growth factor 21 (FGF21), insulin-like growth factor- 1 (IGF-1), BAIBA (P-aminoisobutyric acid), meteorin-like (METRNL), angiopoietin-like 4 (ANPTL4), chemokine (C-C motif) ligand 2 (CCL2), chitinase-3-like protein 1 (CHI3L1), connective tissue growth factor (CTGF), and follistatin.

[0212] The present invention further relates to the use of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or an isolated polypeptide being a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQID NO: 4; or a pharmaceutical composition comprising the same; for the manufacture of a of a medicament for preventing and / or treating a disease selected from the group consisting of angiogenesis defect-related diseases, insulin sensitivity-related diseases, inflammatory conditions and in particular chronic inflammatory conditions, cancer, cognitive diseases, and metabolic diseases.

[0213] In some further aspect, the invention pertains to a method for the prevention and / or the treatment of a muscular disease in an individual in need thereof, comprising the administration of a therapeutically efficient amount of an isolated nucleic acid molecule, or an isolated polypeptide, or a vector according to the instant invention. The present invention thus relates to a method of preventing and / or treating a muscular disease in a subject, comprising administering to said subject a therapeutically effective amount of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or of a vector comprising the same; or of an isolated polypeptide encoded by the same; or of a pharmaceutical composition comprising the same. The present invention also relates to a method of preventing and / or treating a muscular disease in a subject, comprising administering to said subject a therapeutically effective amount of an isolated nucleic acid molecule encoding sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, or of a vector comprising the same; or of an isolated polypeptide encoded by the same; or of a pharmaceutical composition comprising the same.

[0214] In some embodiments, the muscular disease is a geriatric muscular disease.

[0215] In some embodiments, the muscular disease is selected from the group consisting of frailty syndrome and sarcopenia.

[0216] In some embodiments, the muscular disease is frailty syndrome. The present invention thus relates to a method of preventing and / or treating frailty syndrome in asubject, comprising administering to said subject a therapeutically effective amount of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or of a vector comprising the same; or of an isolated polypeptide encoded by the same; or of a pharmaceutical composition comprising the same.

[0217] In some embodiments, the muscular disease is sarcopenia. The present invention thus relates to a method of preventing and / or treating sarcopenia in a subject, comprising administering to said subject a therapeutically effective amount of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or of a vector comprising the same; or of an isolated polypeptide encoded by the same; or of a pharmaceutical composition comprising the same.

[0218] In some embodiments, the muscular disease is characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle. The present invention thus relates to a method of preventing and / or treating a muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle as described herein in a subject, comprising administering to said subject a therapeutically effective amount of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or of a vector comprising the same; or of an isolatedpolypeptide encoded by the same; or of a pharmaceutical composition comprising the same.

[0219] In some embodiments, the isolated nucleic acid molecule is comprised in a vector selected from the group consisting of an adeno-associated viral vector (AAV), an exosome-associated AAV vector (exo-AAV), an exosome, an adenoviral vector, a retroviral vector, a herpes virus vector, a plasmid, and a naked DNA molecule.

[0220] In some embodiments, the vector is a viral vector selected from the group consisting of an adeno-associated viral vector (AAV), an adenoviral vector a retroviral vector, and a herpes virus vector.

[0221] In some embodiments, the vector is an exosome -based vector selected from the group consisting of an exosome-associated AAV vector (exo-AAV), and an exosome. In some embodiments, the vector is selected from the group consisting of a plasmid, and a naked DNA molecule.

[0222] In some embodiments, the method further comprises administering to said subject another therapeutic agent.

[0223] In some embodiments, the SIRT6 protein or variant of SIRT6 as described hereinabove, or the nucleic acid molecule encoding thereof, is transiently expressed in the subject.

[0224] The present invention further relates to a method for preventing loss of muscle mass in a subject, comprising administering to said subject an effective amount of an isolated nucleic acid molecule encoding sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1; or of an isolated polypeptide encoded by the same; or of a composition comprising the same. The present invention further relates to a method for preventing loss of muscle mass in a subject, comprising administering to said subject an effective amount of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant ofSIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or of an isolated polypeptide encoded by the same; or of a composition comprising the same.

[0225] The present invention further relates to a method for preserving and / or restoring endocrine function of a muscle in a subject, comprising administering to said subject an effective amount of an isolated nucleic acid molecule encoding sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1; or of an isolated polypeptide encoded by the same; or of a composition comprising the same. The present invention further relates to a method for preserving and / or restoring endocrine function of a muscle in a subject, comprising administering to said subject an effective amount of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or of an isolated polypeptide encoded by the same; or of a composition comprising the same.

[0226] In some embodiments, the endocrine function is related to lipid metabolism and / or glucose metabolism.

[0227] The present invention further relates to a method for increasing heterochromatin compaction in a eukaryotic cell or a population of eukaryotic cells or a subject, comprising administering to said subject an effective amount of an isolated nucleic acid molecule encoding sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1 ; or of an isolated polypeptide encoded by the same; or of a composition comprising the same. The present invention further relates to a method for increasing heterochromatin compaction in a eukaryotic cell or a population of eukaryotic cells or a subject, comprising contacting said cell with an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1,preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or with an isolated polypeptide encoded by the same.

[0228] The present invention further relates to a method for reducing the expression of transposable elements (TEs) in a eukaryotic cell or a population of eukaryotic cells or a subject, comprising administering to said subject an effective amount of an isolated nucleic acid molecule encoding sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1; or of an isolated polypeptide encoded by the same; or of a composition comprising the same. The present invention further relates to a method for the reducing the expression of transposable elements (TEs) in a eukaryotic cell or a population of eukaryotic cells or a subject, comprising contacting said cell with an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or with an isolated polypeptide encoded by the same.

[0229] The present invention further relates to a method for increasing histone 3 lysine 9 trimethylation (H3K9me3) in a eukaryotic cell or a population of eukaryotic cells or a subject, comprising administering to said subject an effective amount of an isolated nucleic acid molecule encoding sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1; or of an isolated polypeptide encoded by the same; or of a composition comprising the same. The present invention further relates to a method for the increasing histone 3 lysine 9 trimethylation (H3K9me3) in a eukaryotic cell or a population of eukaryotic cells or a subject, comprising contacting said cell with an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleicacid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or with an isolated polypeptide encoded by the same.

[0230] The present invention further relates to a method for increasing the expression and / or the function of at least one myokine in a eukaryotic cell or a population of eukaryotic cells or a subject, comprising administering to said subject an effective amount of an isolated nucleic acid molecule encoding sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1 ; or of an isolated polypeptide encoded by the same; or of a composition comprising the same. The present invention further relates to a method for increasing the expression and / or the function of at least one myokine in a eukaryotic cell or a population of eukaryotic cells or a subject, comprising contacting said cell with an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or with an isolated polypeptide encoded by the same.

[0231] In some embodiments, the at least one myokine is selected from the group consisting of osteonectin (SPARC), cathepsin B, brain-derived neurotrophic factor (BDNF), irisin, apelin, myostatin (GDF-8), myonectin (CTRP15), decorin, peroxisome proliferator activated receptor gamma 1 -alpha coactivator (PGC-1 alpha), leukemia inhibitory factor (LIF), oncostatin M, interleukin 6 (IL-6), interleukin 15 (IL- 15), fibroblast growth factor 21 (FGF21), insulin-like growth factor- 1 (IGF-1), BAIBA ([3- aminoisobutyric acid), meteorin-like (METRNL), angiopoietin-like 4 (ANPTL4), chemokine (C-C motif) ligand 2 (CCL2), chitinase-3-like protein 1 (CHI3L1), connective tissue growth factor (CTGF), and follistatin.

[0232] In some embodiments, the expression and / or function of the at least one myokine is increased by 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%,30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or more, compared to an untreated eukaryotic cell or population of eukaryotic cells or subject.

[0233] The present invention further relates to a method for transiently expressing the SIRT6 protein or variant of SIRT6 as described hereinabove in a subject. The present invention further relates to an in vitro method for transiently expressing the SIRT6 protein or variant of SIRT6 as described hereinabove in a cell or population of cells.

[0234] Another aspect of the invention relates to a kit comprising (i) an isolated nucleic acid, an isolated polypeptide molecule, a vector, or a suspension according to the instant invention, and (ii) means to administer the isolated nucleic acid molecule, the isolated polypeptide, the vector, or the suspension.

[0235] In some embodiments, the means to administer the isolated nucleic acid molecule, the isolated polypeptide, the vector, or the suspension include a syringe or a catheter.

[0236] In certain embodiments, the individual in need thereof is a mammalian individual, preferably a human individual.

[0237] In some embodiments, the individual is suffering or at risk of suffering from a muscular disease.

[0238] Another aspect of the invention relates to an isolated nucleic acid molecule as described herein, or an isolated polypeptide as described herein, or a vector as described herein, or a pharmaceutical composition as described herein, or a cell as described herein, for treating and / or preventing a disease associated with altered expression and / or function of one or more myokine, preferably a myokine selected from the group consisting of myostatin, IL-6, IL- 15, IGF, and FGF-21. Another aspect of the invention relates to the use of an isolated nucleic acid molecule as described herein, or an isolated polypeptide as described herein, or a vector as described herein, or a pharmaceutical composition as described herein, or a cell as described herein, for the manufacture of a medicament for treating and / or preventing a disease associated with altered expression and / or function of one or more myokine, preferably a myokine selected from the group consisting ofmyostatin, IL-6, IL- 15, IGF, and FGF-21. Another aspect of the invention relates to a method for treating and / or preventing a disease associated with altered expression and / or function of one or more myokine in a subject, preferably a myokine selected from the group consisting of myostatin, IL-6, IL-15, IGF, and FGF-21, comprising administering to said subject a therapeutically effective dose of an isolated nucleic acid molecule as described herein, or an isolated polypeptide as described herein, or a vector as described herein, or a pharmaceutical composition as described herein, or a cell as described herein. In some embodiments, the disease is diabetes.

[0239] Another aspect of the invention relates to an isolated nucleic acid molecule as described herein, or an isolated polypeptide as described herein, or a vector as described herein, or a pharmaceutical composition as described herein, or a cell as described herein, for treating and / or preventing a muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle selected from the group consisting of sarcopenia, cancer cachexia, neuromuscular diseases such as Amyotrophic Lateral Sclerosis and Charcot-Marie-Tooth disease, and myopathies. Another aspect of the invention relates to the use of an isolated nucleic acid molecule as described herein, or an isolated polypeptide as described herein, or a vector as described herein, or a pharmaceutical composition as described herein, or a cell as described herein, for the manufacture of a medicament for treating and / or preventing a muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle selected from the group consisting of sarcopenia, cancer cachexia, neuromuscular diseases such as Amyotrophic Lateral Sclerosis and Charcot-Marie-Tooth disease, and myopathies. Another aspect of the invention relates to a method for treating and / or preventing a muscular disease characterized by loss of muscle mass and / or alteration of the endocrine function of the muscle selected from the group consisting of sarcopenia, cancer cachexia, neuromuscular diseases such as Amyotrophic Lateral Sclerosis and Charcot-Marie-Tooth disease, and myopathies, comprising administering to said subject a therapeutically effective dose of an isolated nucleic acid molecule as described herein, or an isolated polypeptide as described herein, or a vector as described herein, or a pharmaceutical composition as described herein, or a cell as described herein. In some embodiments, the disease is diabetes.

[0240] Another aspect of the invention relates to an AAV vector, preferably an AAV8 vector, comprising a nucleic acid molecule encoding a SIRT6 protein having an amino acid sequence with at least 75% sequence identity with SEQ ID NO: 1, optionally wherein the nucleic acid molecule has at least 75% sequence identity with SEQ ID NO: 5; or a pharmaceutical composition comprising thereof; or a cell comprising thereof; for use for preventing and / or treating a muscular disease in a subject in need thereof; wherein the nucleic acid molecule is transiently expressed in the subject; preferably wherein the SIRT6 protein is a SIRT6 variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, more preferably wherein the SIRT6 variant has an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3, and SEQ ID NO: 4, even more preferably wherein the SIRT6 variant has an amino acid sequence of SEQ ID NO: 4; preferably wherein the muscular disease is selected from the group consisting of sarcopenia and frailty syndrome. Another aspect of the invention relates to an AAV vector, preferably an AAV8 vector, comprising a nucleic acid molecule encoding a SIRT6 protein having an amino acid sequence with at least 75% sequence identity with SEQ ID NO: 1, optionally wherein the nucleic acid molecule has at least 75% sequence identity with SEQ ID NO: 5; or a pharmaceutical composition comprising thereof; or a cell comprising thereof; for use for preventing and / or treating a muscular disease characterized by loss of muscle mass and alteration of the endocrine function of the muscle in a subject in need thereof; wherein the nucleic acid molecule is transiently expressed in the subject; preferably wherein the SIRT6 protein is a SIRT6 variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, more preferably wherein the SIRT6 variant has an amino acid sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3, and SEQ ID NO: 4, even more preferably wherein the SIRT6 variant has an amino acid sequence of SEQ ID NO: 4; preferably wherein the muscular disease is further characterized by an altered expression and / or function of one or more myokine selected from the group consisting of myostatin, IL-6, IL-15, IGF, and FGF-21.BRIEF DESCRIPTION OF THE DRAWINGS

[0241] Figure 1 is a histogram showing that AAV-mediated overexpression of human SIRT6 (hSIRT6) and centenarian SIRT6 (centS6) reduces frailty in aged mice. Frailty index scores in mice at 18 months of age, 2 months post-injection, compared to control mice.

[0242] Figure 2 is a graph showing that AAV-mediated overexpression of hSIRT6 and centenarian SIRT6 enhances survival in aged mice (Kaplan-Meier survival curves).

[0243] Figure 3 is a graph showing that overexpression of hSIRT6 and centS6 contributes to improved maintenance of body weight over time.

[0244] Figure 4A-4C is a set of graph, photograph and histogram showing that DNA methylation age and H3K9me3 show more youthful signature upon SIRT6 overexpression (OE) in human dermal fibroblasts (HDF). (Fig. 4A) Methylation clock estimation of each individual sample, n=10 individuals. The mean age was 46.4 years for the control and 43.6 years for SIRT OE. (Fig. 4B) WB analysis of the protein levels of H3K9me3. (Fig. 4C) Relative H3K9me3 protein levels are normalized relative to [3-actin and quantified.

[0245] Figure 5A-5C is a set of graphs and histogram showing transposable elements (TEs) expression analysis in HDF. Volcano plots showing the differential expression of transposable elements (TEs) in (Fig. 5A) RNA-seq, (Fig. 5B) ATAC-seq, and (Fig. 5C) Methylation Immunoprecipitation Sequencing (MeDIP-seq). Light grey circles indicate all TEs with statistically significant changes in expression.

[0246] Figure 6A-6B is a set of graphs showing that chromatin remodeler or chromatin associated genes are upregulated or exhibit increased accessibility upon SIRT6 OE. (Fig. 6A) RNA analysis showing upregulated GO term enrichment. (Fig. 6B) ATAC-seq analysis identifying genes associated with differentially accessible chromatin peaks (DA peaks).

[0247] Figure 7A-7D is a set of photographs showing delivery of hSIRT6 (SEQ ID NO: 1), centernarianSIRT6 (centSIRT6; SEQ ID NO: 4), and luciferase via adeno-associated viruses (AAVs) in aged mice. (Fig. 7A) Schematic representation of the constructs, viral vectors, and injection routes used in the study. (Fig. 7B) WB analysis of SIRT6 expression in the liver of male and female mice 2 months post-injection (p.i.) with AAV8- hSIRT6, AAV-centSIRT6, and AAVluciferase. (Fig. 7C) IVIS imaging at 2 months and 8 months p.i in luciferase mouse. (Fig. 7A) WB analysis of multiple tissues from male mouse injected with AAV8-hSIRT6 at 2 months p.i.

[0248] Figure 8A-8B is a set of histogram and graph showing that AAV-mediated overexpression of hSIRT6 and centSIRT6 reduces frailty and maintains body weight in aged male mice. (Fig. 8A) The frailty index scores demonstrate a significant reduction in FI for mice overexpressing hSIRT6 and centSIRT6 at 18 months of age, 2 months postinjection, compared to control mice. (Fig. 8B) Overexpression of hSIRT6 and centS6 contributes to improved maintenance of body weight over time.EXAMPLES

[0249] The present invention is further illustrated by the following examples.Example 1:

[0250] Sirtuin 6 (SIRT6) plays important roles in multiple regulatory functions including DNA repair, heterochromatin regulation, and telomere maintenance. Overexpression of SIRT6 extends lifespan in mice and SIRT6 activity correlates with maximum lifespan in mammalian species. It was investigated whether SIRT6-based therapies can be used to delay aging.

[0251] Overexpression (OE) of human SIRT6 in cells from elderly subjects rejuvenated the epigenetic clock. RNAseq data indicate that SIRT6 OE upregulated genes involved in heterochromatin assembly, organization, and DNA packaging. Furthermore, SIRT6 OE reduced the expression of transposable elements (TEs), which became more compacted as measured by ATACseq and more methylated as measured by MeDip. SIRT6 overexpression increased H3K9me3, which is associated with heterochromatin.

[0252] These results indicate that SIRT6 regulates global chromatin structure and facilitates heterochromatin compaction, in turn repressing transposable elements.

[0253] To test whether the rejuvenating effects of SIRT6 observed in vitro can be replicated in aging mice, adeno-associated viral vectors of serotype 8 (AAV8) carrying wild-type human SIRT6 (hSIRT6) and centenarian SIRT6 (centSIRT6) were generated.

[0254] The results demonstrate that SIRT6 gene transfer significantly decreased the frailty index score, suggesting a delay in aging-associated phenotypes. AAV-mediated SIRT6 gene transfer may represent a promising gene therapy strategy to delay aging and promote healthy longevity.Materials and Methods

[0255] Mice were injected with AAV vectors carrying luciferase (control), human SIRT6 (hSIRT6) corresponding to SEQ ID NO: 1, and centenarian SIRT6 (centS6) corresponding to SEQ IF NO: 4, at 16 months of age. The frailty index (FI) was used to assess overall health outcomes.Results

[0256] The frailty index scores demonstrate a significant reduction in FI for male mice overexpressing hSIRT6 and centenarian SIRT6 (centS6) at 18 months of age, 2 months post-injection, compared to control male mice (see Fig. 1).

[0257] hSIRT6 and centS6 mice increased survival compared to control mice. Control (n=21), hSIRT6 (n=16), and centS6 (n=16) (see Fig. 2).

[0258] hSIRT6 and centS6 mice also improved maintenance of body weight over time compared to control mice (see Fig. 3).

[0259] With aging, there are significant epigenetic changes at all levels of chromatin and DNA organization. The aging process is accelerated by epigenetic alterations, such as reduced global heterochromatin, nucleosome remodeling and loss, and changes in histone marks. Sirtuin 6 (SIRT6) plays important roles in multiple regulatory functions including DNA repair, heterochromatin regulation, and telomere maintenance. Overexpression of SIRT6 extends lifespan in model organisms and SIRT6 activity correlates with maximum lifespan in mammalian species. There is growing evidence that SIRT6 is a key regulator of genome and epigenome stability. The overarching role of this project is to understand the mechanisms by which SIRT6 rejuvenates the epigenome.Materials and Methods

[0260] As seen on Figure 7A-7D hSIRT6 (SEQ ID NO: 1), centernarianSIRT6 (centSIRT6; SEQ ID NO: 4), and luciferase via adeno-associated viruses (AAVs) were delivered in aged mice, and expression was analyzed 2 months post-injection in multiple tissues and by luciferase imaging.Results

[0261] Figure 4A-4C shows that DNA methylation age and H3K9me3 have a moreyouthful signature upon SIRT6 overexpression (OE) in human dermal fibroblasts (HDF) compared to the control (without OE), as seen with the methylation clock estimation (Fig. 4A). Fig. 4B-4C shows an increase in the H3K9me3 to P-actin ratio, indicating an increase in H3K9me3.

[0262] Further, SIRT6 was found to maintain epigenomic stability, as seen on Figure5A-5C showing transposable elements (TEs) expression analysis in HDF, and on Figure 6A-6B showing that chromatin remodeler or chromatin associated genes are upregulated or exhibit increased accessibility upon SIRT6 OE.

[0263] Finally, it was found that SIRT6 overexpression in aged mice improves heath parameters, as seen on Figure 8A-8B showing that AAV-mediated overexpression of hSIRT6 and centSIRT6 reduces frailty and maintains body weight in aged male mice.

[0264] In conclusion, the above results demonstrate that:

[0265] - SIRT6 facilitates epigenetic remodeling which leads to epigenetic rejuvenation

[0266] - SIRT6 maintains epigenomic stability by preventing the activation of transposable elements.

[0267] - SIRT6 overexpression in aged mice improves heath parameters.

Claims

CLAIMS1. An isolated nucleic acid molecule encoding a sirtuin 6 (SIRT6) protein having at least 75% identity with sequence SEQ ID NO: 1, for use for preventing and / or treating a muscular disease.

2. The nucleic acid molecule for use according to claim 1, wherein the SIRT6 protein is a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1.

3. The nucleic acid molecule for use according to claim 2, wherein the nucleic acid molecule is of sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8.

4. An isolated polypeptide encoded by a nucleic acid molecule according to any one of claims 1 to 3, for use for preventing and / or treating a muscular disease.

5. The isolated polypeptide for use according to claim 4, wherein the polypeptide is of sequence selected from the group consisting of SEQ ID NO: 2, SEQ ID NO: 3 and SEQ ID NO: 4.

6. A vector comprising the isolated nucleic acid molecule according to any one of claims 1 to 3, for use for preventing and / or treating a muscular disease.

7. The vector for use according to claim 6, wherein the vector is selected from the group consisting of an adeno-associated viral vector (AAV), an extracellular vesicle-associated AAV such as an exosome-associated AAV vector (exo-AAV), an extracellular vesicle such as an exosome, an adenoviral vector, a retroviral vector, a herpes virus vector, a plasmid, and a naked nucleic acid molecule such as a DNA molecule or a mRNA molecule.

8. The vector for use according to claim 6, wherein the vector is a viral vector selected from the group consisting of an adeno-associated viral vector (AAV), an adenoviral vector a retroviral vector, and a herpes virus vector.

9. The vector for use according to claim 6, wherein the vector is an exosome-based vector selected from the group consisting of an exosome-associated AAV vector (exo-AAV), and an exosome.

10. The vector for use according to claim 6, wherein the vector is selected from the group consisting of a plasmid, and a a naked nucleic acid molecule such as a DNA molecule or a mRNA molecule.

11. A composition comprising an isolated nucleic acid molecule according to any one of claims 1 to 3, or an isolated polypeptide according to claim 4 or 5, or a vector according to any one of claims 6 to 10, for use for preventing and / or treating a muscular disease, preferably wherein said composition is a suspension.

12. A cell comprising the polypeptide according to claim 4 or 5, the cell being preferably transfected with an isolated nucleic acid molecule according to any one of claims 1 to 3, or a vector according to any one of claims 6 to 10, for use for preventing and / or treating a muscular disease.

13. The cell for use according to claim 12, wherein the cell is a progenitor cell.

14. The cell for use according to claim 13, wherein the progenitor cell is a muscle progenitor cell.

15. The cell for use according to claim 14, wherein the muscle progenitor cell is a skeletal muscle progenitor cell.

16. A pharmaceutical composition comprising (i) an isolated nucleic acid molecule according to any one of claims 1 to 3, or an isolated polypeptide according to claim 4 or 5, or a vector according to any one of claims 6 to 10, and (ii) a pharmaceutically acceptable excipient, for use for preventing and / or treating a muscular disease.

17. The isolated acid nucleic molecule for use according to any one of claims 1 to 3, the isolated polypeptide for use according to claim 4 or 5, the vector for use according to any one of claims 6 to 10, the composition for use according to claim 10, the cell for use according to any one of claims 12 to 15, or the pharmaceutical composition for use according to claim 16, wherein the muscular disease is characterized by loss of muscle mass and alteration of the endocrine function of the muscle.

18. The isolated acid nucleic molecule for use according to any one of claims 1 to 3, the isolated polypeptide for use according to claim 4 or 5, the vector for use according to any one of claims 6 to 10, the composition for use according to claim 10, the cell for use according to any one of claims 12 to 15, or the pharmaceutical composition for use according to claim 16, wherein the muscular disease is a geriatric muscular disease.

19. The isolated acid nucleic molecule for use according to any one of claims 1 to 3, the isolated polypeptide for use according to claim 4 or 5, the vector for use according to any one of claims 6 to 10, the composition for use according to claim 10, the cell for use according to any one of claims 12 to 15, or the pharmaceutical composition for use according to claim 16, wherein the muscular disease is selected from the group consisting of frailty syndrome and sarcopenia.

20. The isolated acid nucleic molecule for use according to any one of claims 1 to 3, the isolated polypeptide for use according to claim 4 or 5, the vector for use according to any one of claims 6 to 10, the composition for use according to claim 10, the cell for use according to any one of claims 12 to 15, or the pharmaceutical composition for use according to claim 16, wherein the muscular disease is frailty syndrome.

21. The isolated acid nucleic molecule for use according to any one of claims 1 to 3, the isolated polypeptide for use according to claim 4 or 5, the vector for use according to any one of claims 6 to 10, the composition for use according to claim 10, the cell for use according to any one of claims 12 to 15, or the pharmaceuticalcomposition for use according to claim 16, wherein the muscular disease is sarcopenia.

22. A method of preventing and / or treating a muscular disease in a subject, comprising administering to said subject a therapeutically effective amount of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or of an isolated polypeptide encoded by the same; or of a pharmaceutical composition comprising the same.

23. Use of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or pharmaceutical composition comprising the same, for the manufacture of a medicament for preventing and / or treating a muscular disease.

24. A method for preventing loss of muscle mass in a subject, comprising administering to said subject an effective amount of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or of an isolated polypeptide encoded by the same; or of a composition comprising the same.

25. A method for preserving and / or restoring endocrine function of a muscle in a subject, comprising administering to said subject an effective amount of an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or of an isolated polypeptide encoded by the same; or of a composition comprising the same.

26. The method according to claim 24, wherein the endocrine function is related to lipid metabolism and / or glucose metabolism.

27. A method for increasing heterochromatin compaction in a eukaryotic cell, comprising contacting said cell with an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or with an isolated polypeptide encoded by the same.

28. A method for the reducing the expression of transposable elements (TEs) in a eukaryotic cell, comprising contacting said cell with an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitution A313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or with an isolated polypeptide encoded by the same.

29. A method for the increasing histone 3 lysine 9 trimethylation (H3K9me3) in a eukaryotic cell, comprising contacting said cell with an isolated nucleic acid molecule encoding a variant of sirtuin 6 (SIRT6) having at least 75% identity with sequence SEQ ID NO: 1, said variant of SIRT6 having at least one mutation selected from the group consisting of a substitution N308K and a substitutionA313S with respect to sequence SEQ ID NO: 1, preferably said variant of SIRT6 having a nucleic acid sequence selected from the group consisting of SEQ ID NO: 6, SEQ ID NO: 7 and SEQ ID NO: 8; or with an isolated polypeptide encoded by the same.

Images