Pharmaceutical composition for preventing or treating muscle weakness-related diseases, comprising alverine, 4-hydroxyalverine, a derivative thereof, or a pharmaceutically acceptable salt thereof

Abstract

The present invention relates to a pharmaceutical composition for preventing or treating muscle weakness-related diseases, comprising alverine, 4-hydroxyalverine, a derivative thereof, or a pharmaceutically acceptable salt thereof. Treatment of myoblasts with the alverine, 4-hydroxyalverine, a derivative thereof, or a pharmaceutically acceptable salt thereof of the present invention promotes their differentiation into myotubes. Therefore, the alverine, 4-hydroxyalverine, a derivative thereof, or a pharmaceutically acceptable salt thereof according to the present invention can be effectively used to promote myoblast differentiation and prevent or treat muscle weakness-related diseases.

Description

Detailed Description of the Invention

[0001] [Technical field] The present invention relates to a pharmaceutical composition for preventing or treating muscle weakness-related conditions, comprising alverine, 4-hydroxyalverine, a derivative thereof, or a pharmaceutically acceptable salt thereof.

[0002] [Background technology] Diseases associated with muscle weakness include sarcopenia, which progresses with age, and muscular dystrophy, a degenerative myopathy accompanied by necrosis of muscle fibers due to genetic mutations.

[0003] Sarcopenia is a gradual decline in muscle strength due to a decrease in muscle mass associated with aging. Sarcopenia occurs not only with a decrease in muscle mass but also with a change in muscle fiber type. Sarcopenia is the cause of various aging phenomena and functional disorders observed in elderly people. Muscular dystrophy is a condition characterized by muscle fiber necrosis and degeneration due to the deletion or mutation of muscle-related genes, leading to disability and death. Cachexia is a condition characterized by a decrease in muscle strength and is often observed in cancer patients. In cancer patients, excessive catabolism of skeletal muscle due to increased metabolism often leads to a decrease in muscle mass and strength. These metabolic abnormalities eventually reach a stage where they cannot be reversed even by food intake, necessitating more aggressive treatment, such as drug therapy.

[0004] Currently, there are no definitive drug candidates for sarcopenia, as clinical trials have shown limited efficacy (Ju Yeon Kwak, Ki-Sun Kwon, Ann Geriatr Med Res. 98-104, 2019). Therefore, adjunctive physical exercise and nutritional supplementation are currently the only safe and effective treatments. Physical exercise is thought to have beneficial effects on skeletal muscle through various mechanisms, including mTORC1 activation, reduction of oxidative stress, reduction of inflammation, and increased mitochondrial production (Jiayu Yin et al., Theranostics, 4019-4029, 2019). While physical exercise and nutritional supplementation can improve muscle strength, muscle function, and muscle mass, their effects are limited, making it difficult for elderly people who are unable to exercise due to physical disabilities or who have poor nutrient absorption to benefit from these treatments.

[0005] However, sarcopenia is a multifactorial disease with various causes, and there are no consistent diagnostic criteria for it due to the large disparities in muscle mass across race, age, and gender. In 2019, the European Working Group of Patients' Organization (EWGSOP) further classified sarcopenia into suspected sarcopenia, confirmed sarcopenia, and severe sarcopenia based on muscle mass, strength, and physical performance (AJ Cruz-Jentoft et al., Age Ageing, 601, 2019). While the molecular biological mechanisms underlying sarcopenia are not clearly understood, mitochondrial fusion / fission failure, oxidative stress, inflammation, and stem cell depletion are thought to be the causes of sarcopenia (Jessica Hiu-tung Lo et al., J Orthop Translat, 38-52, 2020).

[0006] Satellite cells are stem cells found in adult muscle and are required for the regeneration of injured skeletal muscle. Age-related decline in satellite cell numbers in mice has been observed. In humans, a decrease in satellite cell numbers has been observed in type II muscle. This decrease in satellite cell numbers may contribute to the development of sarcopenia and may be associated with the failure of muscle regeneration in aged animals (Carlson et al., J Gerontol, B224-233, 2001).

[0007] Previous studies of skeletal muscle hypertrophy and regeneration have focused on the regulation of myoblast differentiation by myogenic regulatory factors (MRFs), such as MyoD, Mef2, and myogenin (Sabourin LA and Rudnicki MA, Clin Genet. 2000 Jan;57(1):16-25). Drug therapy to enhance myoblast differentiation and regeneration leads to muscle hypertrophy and improved muscle function, and many attempts have been made to address the age-related decline in muscle function using this approach (Francesca Riuzzi et al., J Cachexia Sarcopenia Muscle, 1255-1268, 2018; Mary F. O'Leary, Sci Rep. 12997, 2017; Jin-A Kim and Seong Min Kim, BMC Complement Alternative Med, 287, 2019). Therefore, improving satellite cell function and increasing the satellite cell pool may be a strategy to suppress the onset of sarcopenia and improve muscle regeneration. Therefore, there is a need to develop substances that can promote myoblast differentiation. [Prior art documents] [Non-patent literature]

[0008] [Non-Patent Document 1] Ju Yeon Kwak, Ki-Sun Kwon, Ann Geriatr Med Res. 98-104, 2019 [Non-patent document 2] Jiayu Yin, Xiang Lu, Zhiyuan Qian, Weiting Xu and Xiang Zhou, Theranostics, 4019-4029, 2019 [Non-patent document 3] AJ Cruz-Jentoft et al.,Age Aging,601,2019 [Non-patent document 4] Jessica Hiu-tung Lo,Kin PongU,TszlamYiu,J Orthop Translat,38-52,2020 [Non-Patent Document 5] Carlson et al., J Gerontol, B224-233, 2001 [Non-patent document 6] Sabourin LA, Rudnicki MA., Clin Genet.2000 Jan;57(1):16-25 [Non-Patent Document 7] Francesca Riuzzi,Guglielmo Sorci,Cataldo Arcuri,J Cachexia Sarcopenia Muscle,1255-1268,2018 [Non-patent document 8] Mary F.O'Leary,Sci Rep.12997,2017 [Non-Patent Document 9] Jin-A Kim,Seong Min Kim,BMC Complement Altern Med,287,2019

[0009] [DISCLOSURE OF THE INVENTION] [Technical issues] The present inventors have endeavored to develop a substance that can increase muscle mass and effectively restore muscle function by promoting myoblast differentiation, and as a result, they have discovered that alverine, 4-hydroxyalverine, their derivatives, and pharmaceutically acceptable salts thereof promote myoblast differentiation and restore muscle strength, thereby arriving at the present invention.

[0010] [Solution to the problem] In order to solve the above problems, one aspect of the present invention provides a compound represented by formula 1 and a pharmaceutically acceptable salt thereof.

[0011] Another aspect of the present invention provides a pharmaceutical composition for preventing or treating a condition associated with muscle weakness, comprising the compound or a pharmaceutically acceptable salt thereof as an active ingredient.

[0012] Another aspect of the present invention provides a composition for promoting myoblast differentiation ex vivo, which comprises the compound or a pharmaceutically acceptable salt thereof as an active ingredient.

[0013] Another aspect of the invention provides a method for promoting myoblast differentiation, comprising treating myoblasts ex vivo with the compound or a pharmaceutically acceptable salt thereof.

[0014] Another aspect of the present invention provides a method for preparing myotubes, comprising treating myoblasts ex vivo with the compound or a pharmaceutically acceptable salt thereof, thereby causing the myoblasts to differentiate.

[0015] Another aspect of the present invention provides a food composition for preventing or alleviating a condition associated with muscle weakness, comprising a compound represented by formula 1 or a nutrient-acceptable salt thereof.

[0016] Another aspect of the present invention provides a composition for enhancing muscle strength, which comprises the compound or a pharmaceutically acceptable salt thereof as an active ingredient.

[0017] Another aspect of the present invention provides a method for preventing or treating a condition associated with muscle weakness, comprising administering to a subject a compound represented by Formula 1 or a pharmaceutically acceptable salt thereof.

[0018] Another aspect of the present invention provides the use of a compound of formula 1, or a pharmaceutically acceptable salt thereof, for the prevention or treatment of a muscle weakness-related condition.

[0019] Another aspect of the present invention provides the use of a compound of formula 1, or a pharmaceutically acceptable salt thereof, for the preparation of a medicament for preventing or treating a muscle weakness-related condition.

[0020] [Advantageous effects of the invention] When administered to myoblasts, the alverine, 4-hydroxyalverine, derivatives thereof, or pharmaceutically acceptable salts thereof of the present invention promote the differentiation of myoblasts into myotubes. Therefore, the alverine, 4-hydroxyalverine, derivatives thereof, or pharmaceutically acceptable salts thereof of the present invention can be advantageously used to promote the differentiation of myoblasts or to prevent or treat conditions associated with muscle weakness. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 shows fluorescent images of myotubes differentiated from myoblasts by treating them with DMSO, insulin, or alverine citrate. [Figure 2] FIG. 2 shows eMyHC fluorescent staining areas in myotubes differentiated by treating myoblasts with DMSO, insulin, or alverine citrate. [Figure 3] FIG. 3 shows the experimental schedule using animals to confirm the muscle-strengthening effect of alverine citrate. [Figure 4] FIG. 4 is a graph showing the measured grip strength of mice as a function of the concentration of administered alverine citrate. [Figure 5] FIG. 5 shows the running time of mice in the normal and experimental groups. [Figure 6] FIG. 6 is a graph showing the time that mice in the normal and experimental groups clung to the rotating rod. [Figure 7] FIG. 7 is a graph showing the muscle mass of the gastrocnemius (GA) and tibialis anterior (TA) obtained from normal and experimental mice. [Figure 8] FIG. 8 shows an experimental schedule using sarcopenia-induced animals to confirm the muscle strength-enhancing effect of alverine citrate. [Figure 9]FIG. 9 shows the running times of mice in the normal group, control group, and experimental group. [Figure 10] FIG. 10 shows a graph showing the muscle mass of the gastrocnemius (GA) and tibialis anterior (TA) muscles obtained from mice in the normal, control, and experimental groups. [Figure 11] FIG. 11 shows fluorescent staining images of myotubes differentiated from myoblasts by treating them with DMSO, insulin, alverine citrate, or 4-hydroxyalverine (4HA). [Figure 12] FIG. 12 shows a graph showing the areas of eMyHC fluorescent staining in myotubes differentiated by treating myoblasts with DMSO, insulin, alverine citrate, or 4-hydroxyalverine (4HA). [Figure 13] FIG. 13 shows fluorescent staining images of myotubes in which atrophy was induced by a cancer cell conditioned medium (CM) containing alverine citrate (AC) or 4-hydroxyalverine (4HA). [Figure 14] FIG. 14 is a graph showing the diameter of myotubes in which atrophy was induced by cancer cell conditioned medium (CM) containing alverine citrate (AC) or 4-hydroxyalverine (4HA). [Figure 15] FIG. 15 shows fluorescent staining images of myotubes differentiated from myoblasts by treating them with DMSO, alverine, and 27 alverine derivatives, respectively. [Figure 16] FIG. 16 shows a graph showing the area of ​​myotubes differentiated by treating myoblasts with DMSO, alverine, and 27 alverine derivatives, respectively.

[0022] [Best Mode for Carrying Out the Invention] The present invention will now be described in more detail. One aspect of the present invention is a compound represented by the following formula 1 and a pharmaceutically acceptable salt thereof: [Formula 1] [ka] (In formula 1, R1, R2, R4 and R5 are each independently hydrogen, halogen, -CF3, hydroxy, cyano, C 1~10 Alkyl, C 1~10 Alkoxy, C 1~4 Haloalkyl, C 1~10 Haloalkoxy, C 2~4 Alkenyl, C 2~4 Alkynyl, -NHR a , -NHC(=O)R b , -NHC(=O)NHR c , amino-C 1~10 Alkoxy, C 1~10 Alkenyloxy, or C 6~10 Aryl-C 1~10 is an alkoxy, R3 is C 1~10 Alkyl, C 2~12 Alkenyl, C 1~4 Haloalkyl, C 2~4 Alkenyl, or C 2-4 is alkynyl, R a ~R c are each independently hydrogen, C 1~6 Alkyl, C 1~6 Alkoxy, C 1~4 Haloalkyl, C 2~4 Alkenyl, C 2~4 Alkynyl, or C 6~10 is aryl; n and m are each independently an integer of 1 to 10. to provide.

[0023] As used herein, the term "halo" or "halogen" means F, Cl, Br, or I, unless otherwise indicated.

[0024] The term "alkyl" means, unless otherwise indicated, a straight or branched chain saturated hydrocarbon residue. For example, "C 1~10 "Alkyl" refers to an alkyl group having 1 to 10 carbon atoms in its backbone. 1~10Alkyl can include groups such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, n-pentyl, i-pentyl, t-pentyl, sec-pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, and decyl. The term "alkoxy," unless otherwise specified, refers to a group having the structure -O-alkyl, where an alkyl group, as defined above, is attached to the parent compound through an oxygen atom. The alkyl portion of the alkoxy group can contain 1 to 20 carbon atoms (i.e., C1 to C6). 20 alkoxy), 1 to 12 carbon atoms (i.e., C1 to C 12 The alkoxy group may contain 1 to 6 carbon atoms (i.e., C1-C6 alkoxy), or 1 to 6 carbon atoms (i.e., C1-C6 alkoxy). Examples of suitable alkoxy groups include methoxy (-O-CH3 or OMe), ethoxy (-OCH2CH3 or OEt), t-butoxy (-OC(CH3)3 or O-tBu), and the like.

[0025] The term "haloalkyl" refers to an alkyl group substituted with one or more halogen atoms. More specifically, a haloalkyl can be an alkyl group substituted with two or more of the same halogen or two or more different halogens.

[0026] The term "haloalkoxy" means an alkoxy group substituted with one or more halogen atoms.

[0027] The term "aminoalkoxy" means an alkoxy group substituted with one or more amino groups.

[0028] The term "amino" refers to -NR2, where each "R" is independently selected from H, alkyl, aryl, etc., and typical amino groups include, but are not limited to, -NH2, -N(CH3)2, -NH(CH3), -N(CH2CH3)2, -NH(CH2CH3), -NH(substituted or unsubstituted benzyl), -NH(substituted or unsubstituted phenyl), etc.

[0029] The term "alkenyl" refers to an alkenyl group that has one or more unsaturated moieties, i.e., carbon-carbon, sp 2 For example, an alkenyl group refers to a hydrocarbon having 2 to 20 carbon atoms (i.e., C2 to C6). 20 alkenyl), 2 to 12 carbon atoms (i.e., C2 to C 12 alkenyl), or 2 to 6 carbon atoms (i.e., C2-C6 alkenyl). Examples of suitable alkenyl groups include, but are not limited to, ethylene or vinyl (-CH=CH2), allyl (-CH2CH=CH2), cyclopentenyl (-C5H7), and 5-hexenyl (-CH2CH2CH2CH2CH=CH2).

[0030] Unless otherwise indicated, the term "alkenyloxy" means a group having the structure --O-alkenyl, in which an alkenyl group, as defined above, is attached to the parent compound through an oxygen atom.

[0031] The term "alkynyl" refers to a hydrocarbon having primary, secondary, tertiary, or cyclic carbon atoms with one or more unsaturated moieties, i.e., carbon-carbon, triple bonds. For example, an alkynyl group can be any group having 2 to 20 carbon atoms (i.e., C2 to C6). 20 alkynyl), 2 to 12 carbon atoms (i.e., C2 to C 12 alkynyl), or 2 to 6 carbon atoms (i.e., C2-C6 alkynyl). Suitable alkynyl groups include, but are not limited to, acetylenic (-C≡H), propargyl (-CH2C≡H), and the like.

[0032] As used herein, the term "aryl" means an aromatic hydrocarbon group derived by removing one hydrogen atom from six carbon atoms of a parent aromatic ring system. For example, an aryl group can have 6 to 20 carbon atoms, 6 to 14 carbon atoms, or 6 to 12 carbon atoms.

[0033] As used herein, the term "substituted" means that a hydrogen atom in a molecular structure is replaced with a substituent, resulting in a chemically stable compound without exceeding the valence of the specified atom. For example, "group A is substituted with substituent B" may mean that a hydrogen atom bonded to an atom constituting the skeleton of group A, i.e., a carbon atom, is replaced with substituent B, thereby forming a covalent bond between group A and substituent B.

[0034] According to one example, in Formula 1, R1, R2, R4, and R5 are each independently hydrogen, halogen, hydroxy, C 1~10 Alkyl, C 1~10 Alkoxy, C 1~10 Haloalkoxy, -NHR a , -NHC(=O)R b , -NHC(=O)NHR c , Amino C 1~10 Alkoxy, C 1~10 Alkenyloxy or C 6~10 Aryl-C 1~10 R3 may be C 1~10 Alkyl or C 2~12 may be alkenyl, and R a ~R c are each independently hydrogen, C 1~6 Alkyl, C 1~6 Alkoxy or C 6~10 It may be aryl; n and m may each independently be an integer of 1 to 7.

[0035] According to one example, in Formula 1, R1 and R2 are each independently hydrogen, halogen, hydroxy, C 1~10 Alkyl, C 1~10 Alkoxy, C 1~10 Haloalkoxy, -NHR a , Amino C 1~10 Alkoxy, C 1~10 Alkenyloxy or C 6~10 Aryl-C 1~10 R3 may be C 1~10R4 and R5 may each independently be hydrogen, hydroxy, or -NHR a , -NHC(=O)NHR b , or -NHC(=O)NHR c R may be a ~R c are each independently hydrogen, C 1~4 Alkyl, C 1~6 Alkoxy or C 6~10 It may be aryl; n and m may each independently be an integer of 1 to 5.

[0036] According to another example, in Formula 1, R1 and R2 are each independently hydrogen, halogen, hydroxy, C 1~6 Alkyl, C 1~6 Alkoxy, C 1~6 Haloalkoxy, -NHR a , Amino C 1~10 Alkoxy, C 1~10 Alkenyloxy or C 6~10 Aryl-C 1~6 R3 may be C 1~6 R4 may be hydrogen, halogen, hydroxy, -NHR a , -NHC(=O)NHR b , or -NHC(=O)NHR c R4 may be hydrogen, halogen, hydroxy, -NHR a , -NHC(=O)NHR b , or -NHC(=O)NHR c R5 may be hydrogen, and R a is hydrogen or C 1~6 may be alkoxy, and R b is hydrogen or C 1~6 may be alkyl, R c is hydrogen or C 6~10 It may be aryl, and n and m may each independently be an integer of 1 to 3.

[0037] In another example, in Formula 1, when n and m are each 2, R3 is ethyl, R1, R4, and R5 are each hydrogen, and R2 is hydrogen or hydroxy. In this case, this example may be alverine or 4-hydroxyalverine.

[0038] In particular, Alverine has the structure represented by Formula 2 below. [Formula 2] [ka] Here, Alverine corresponds to the compound of formula 1 where n and m are each 2, R3 is ethyl, and R1, R2, R4 and R5 are all hydrogen.

[0039] As used herein, the term "alverine" has the IUPAC name of N-ethyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine and is C 20 H 27 It refers to a compound with the chemical formula N and a molecular weight of 281.44 g / mol. Alverine is generally known as a drug used for gastrointestinal disorders, but little is known about its relationship to myoblast differentiation.

[0040] 4-hydroxyalverine is a metabolite of alverine, and has the structure of the following formula 3: [Formula 3] [ka] Here, 4-hydroxyalverine corresponds to the compound of formula 1 when n and m are each 2, R3 is ethyl, and three of R1, R2, R4, and R5 are hydrogen and one is hydroxy. Particularly, when three of R1, R2, R4, and R5 are hydrogen and one is hydroxy, the following cases can be mentioned: 1) when R2, R4, and R5 are each hydrogen and R1 is hydroxy; 2) when R1, R4, and R5 are each hydrogen and R2 is hydroxy; iii) when R1, R2, and R5 are each hydrogen and R4 is hydroxy; and iv) when R1, R2, and R4 are each hydrogen and R5 is hydroxy. By way of specific example, specific examples of compounds represented by formula 1 include: 1) 4-(3-ethyl(3-phenylpropyl)amino)propyl)aniline; 2) N-ethyl-3-(4-methoxyphenyl)-N-(3-phenylpropyl)propan-1-amine; 3) N-ethyl-3-phenyl-N-(3-(p-tolyl)propyl)propan-1-amine; 4) 3-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 5) N-methyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; 6) 4,4'-((ethylazanediyl))bis(propane-3,1-diyl))diphenol; 7) 4-(3-(methyl(3-phenylpropyl)amino)propyl)phenol; 8) 4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)aniline; 9) N-(4-(3-((3-)4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 10) 4-(3-(ethyl(phenethyl)amino)propyl)phenol; 11) 4-(3-(ethyl(3-phenylpropyl)amino)propyl)-2-fluorophenol; 12) 2-Bromo-4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 13) 1-(4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)-3-phenylurea; 14) Ethyl(4-phenylbutyl)(3-phenylpropyl)amine; 15) Ethylbis(4-phenylbutyl)amine; 16) (4-phenylbutyl)(3-phenylpropyl)propylamine; 17) 3-(4-butoxyphenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 18) 3-(4-(but-3-en-1-yloxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 19) 3-(4-(4-bromobutoxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 20) 4-(4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenoxy)butan-1-amine; 21) 4-(3-(ethyl(3-(4-methoxyphenyl)propyl)amino)propyl)-2-fluorophenol; 22) 4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)aniline; 23) N-(4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 24) 3-(4-(benzyloxy)-3-fluorophenyl)-N-methyl-N-(3-phenylpropyl)propan-1-amine; 25) 4-(3-(ethyl(3-(p-tolyl)propyl)amino)propyl)-2-fluorophenol; 26) N-ethyl-3-phenyl-N-(3-(4-(3-phenylpropionyl) Epoxy )phenyl)propyl)propan-1-amine; 27) N-ethyl-3-phenyl-N-(3-(4-((5-phenylpentyl)oxy)phenyl)propyl)propan-1-amine; 28) N-ethyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine (i.e., Alverine); and 29) 4-[3-[ethyl(3-phenylpropyl)amino]propyl]phenol (i.e., 4-hydroxyalverine).

[0041] As used herein, the term "pharmaceutically acceptable salt" refers to a salt prepared according to a common method known in the art, and such preparation methods are known to those skilled in the art. In particular, pharmaceutically acceptable salts include, but are not limited to, pharmaceutically or physiologically acceptable salts derived from the following inorganic acids, organic acids, and bases. Suitable examples of such acids include hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, perchloric acid, fumaric acid, maleic acid, phosphoric acid, glycolic acid, lactic acid, salicylic acid, succinic acid, toluene-p-sulfonic acid, tartaric acid, acetic acid, citric acid, methanesulfonic acid, formic acid, benzoic acid, malonic acid, naphthalene-2-sulfonic acid, and benzenesulfonic acid. Salts derived from appropriate bases include alkali metals such as sodium or potassium, and alkaline earth metals such as magnesium. In particular, the pharmaceutically acceptable salt may be a citrate salt. In one example of the present invention, a citrate salt was used as the pharmaceutically acceptable salt.

[0042] Another aspect of the present invention provides a pharmaceutical composition for preventing or treating a condition associated with muscle weakness, comprising, as an active ingredient, a compound represented by Formula 1 or a pharmaceutically acceptable salt thereof, wherein the compound represented by Formula 1 or a pharmaceutically acceptable salt thereof is the same as described above.

[0043] The muscle weakness-related condition refers to any condition caused by muscle weakness, particularly a condition in which the reduction in muscle cells or the reduced activity of satellite cells in the body reduces or weakens myoblast titer, and the promotion of myoblast differentiation is expected to result in prevention, alleviation, or treatment. In particular, the muscle weakness-related condition may be sarcopenia, muscle atrophy, muscular dystrophy, cachexia, etc.

[0044] As used herein, the term "sarcopenia" refers to a condition characterized by a gradual loss of muscle mass with aging, resulting in a decrease in muscle strength. A major cause of muscle mass loss in sarcopenia is thought to be a decrease in satellite cell activity. Satellite cells are activated by stimuli such as exercise or trauma, proliferate into myoblasts, and as they differentiate, fuse with other cells to form multinucleated muscle fibers.

[0045] As used herein, the term "muscular atrophy" refers to a condition characterized by gradual, nearly symmetrical atrophy of limb muscles. Muscular atrophy is a progressive degeneration of motor nerve fibers and cells in the spinal cord, which may lead to amyotrophic lateral sclerosis (ALS) and spinal progressive muscular atrophy (SPMA).

[0046] As used herein, the term "muscular dystrophy" refers to a degenerative muscle disease characterized by necrosis of muscle fibers, regardless of whether it is central or peripheral nervous system involvement. Muscular dystrophy and muscular atrophy have some clinical differences. Muscular dystrophy often develops in childhood, while muscular atrophy often develops in the second decade of life. Muscular dystrophy also affects proximal muscles, whereas muscular atrophy affects distal muscles. Muscular dystrophy exhibits muscle stiffness, whereas muscular atrophy does not. Muscular dystrophy is clearly a hereditary disease, whereas muscular atrophy is rarely inherited.

[0047] As used herein, "cachexia" refers to severe generalized weakness observed in the terminal stages of cancer, tuberculosis, hemophilia, and the like. Cachexia is also considered a state of intoxication caused by dysfunction of various internal organs. Symptoms of cachexia include muscle weakness, rapid weight loss, anemia, drowsiness, and yellowing of the skin. Underlying diseases that can cause cachexia include malignant tumors, Graves' disease, and hypopituitarism. It has also been found that physiologically active substances such as tumor necrosis factor (TNF) produced by macrophages can worsen cachexia.

[0048] In the pharmaceutical composition, the concentration of the compound represented by formula 1 or a pharmaceutically acceptable salt thereof may be 10 μg / ml to 180 μg / ml. More specifically, the concentration of the compound represented by formula 1 or a pharmaceutically acceptable salt thereof may be 20 μg / ml to 160 μg / ml, 40 μg / ml to 140 μg / ml, or 60 μg / ml to 120 μg / ml.

[0049] Furthermore, the dosage of the pharmaceutical composition can be determined based on the amount of the compound represented by formula 1 or a pharmaceutically acceptable salt thereof, which is the administered active ingredient. In particular, the dosage of the compound represented by formula 1 or a pharmaceutically acceptable salt thereof may be 60 mg to 240 mg per day, and in the case of a high dose, it can be administered in 1 to 3 divided doses over the course of a day. Preferably, the dosage of the compound represented by formula 1 or a pharmaceutically acceptable salt thereof is 60 mg to 120 mg, and can be administered once or twice per day.

[0050] The pharmaceutical composition may optionally contain a pharmaceutically acceptable carrier, which is commonly used in the manufacture of pharmaceuticals, and may include lactose, dextrose, sucrose, sorbitol, mannitol, starch, acacia gum, calcium phosphate, alginic acid, gelatin, calcium silicate, microcrystalline cellulose, polyvinylpyrrolidone, cellulose, water, syrup, methylcellulose, methyl hydroxybenzoate, propyl hydroxybenzoate, talc, magnesium stearate, mineral oil, etc.

[0051] The pharmaceutical composition may further comprise a pharmaceutically acceptable excipient selected from the group consisting of a lubricating agent, a wetting agent, a sweetening agent, a flavoring agent, an emulsifying agent, a suspending agent, a preservative, and combinations thereof.

[0052] The pharmaceutical composition can be appropriately administered to a subject according to the method, administration route, and dosage commonly used in the art. In particular, the appropriate dosage and appropriate administration frequency of the pharmaceutical composition can be selected according to a method known in the art, and the actual dosage and administration frequency of the pharmaceutical composition can be determined according to various factors such as the type of symptoms to be prevented or treated, the administration route, sex, physical condition, diet, age and weight of the subject, and the severity of the disease.

[0053] Another aspect of the present invention provides a composition for promoting myoblast differentiation ex vivo, comprising as an active ingredient a compound represented by formula 1 or a pharmaceutically acceptable salt thereof, wherein the compound represented by formula 1 or a pharmaceutically acceptable salt thereof is as described above.

[0054] As used herein, the term "ex vivo" refers to a state in which a part of a living organism, such as a cell or tissue, is extracted and isolated "outside of a living organism." In particular, ex vivo can also refer to "in vitro," in which an experiment is performed on a part of a living organism under artificial conditions.

[0055] Myoblasts are muscle cells in an undifferentiated state. During myoblast differentiation, mononuclear myoblasts fuse to form multinucleated myotubes. During terminal differentiation of myoblasts, the expression of myosin heavy chain (MyHC) increases.

[0056] The composition for promoting differentiation may be a serum-containing DMEM differentiation medium, but is not particularly limited to any medium or composition that can promote myoblast differentiation. In addition, the composition may further contain substances necessary for cell proliferation or differentiation.

[0057] In the pharmaceutical composition, the concentration of the compound represented by formula 1 or a pharmaceutically acceptable salt thereof may be 0.01 μM to 100 μM. In particular, the concentration of the compound represented by formula 1 or a pharmaceutically acceptable salt thereof is 0.1 μM to 50 μM, 0.1 μM to 25 μM, 0.5 μM to 25 μM, 0.1 μM to 10 μM, 0.5 μM to 10 μM, 1 μM to 10 μM, 0.1 μM to 5 μM, 0.5 μM to 5 μM, 1 μM to 5 μM, 0.1 μM to 2 μM, 0.5 μM to 2 μM, or 1 μM to 2 μM. In one example of the present invention, the compound represented by formula 1 or a pharmaceutically acceptable salt thereof was administered to mouse-derived myoblast C2C12 cells at a concentration of 1 μM.

[0058] Another aspect of the present invention provides a method for promoting myoblast differentiation, comprising treating myoblasts ex vivo with a compound represented by Formula 1 or a pharmaceutically acceptable salt thereof. The method for promoting myoblast differentiation may be carried out in vitro or ex vivo.

[0059] Another aspect of the present invention provides a method for preparing myotubes, comprising treating myoblasts ex vivo with a compound of Formula 1 or a pharmaceutically acceptable salt thereof, thereby differentiating the myoblasts. The method for preparing myotubes may be performed in vitro or ex vivo.

[0060] Another aspect of the present invention provides a food composition for preventing or alleviating a condition associated with muscle weakness, comprising a compound represented by formula 1 or a nutrient-acceptable salt thereof. When used as a food additive, the food composition may be added as is or in combination with other food ingredients, and may be used appropriately according to a general method.

[0061] To prevent or alleviate muscle weakness-related conditions, the food composition can be used before or after the onset of muscle weakness-related conditions, either simultaneously with or separately from a drug used to treat the disease. In particular, the food composition is characterized by promoting myoblast differentiation. The muscle weakness-related conditions are the same as those described for the pharmaceutical composition.

[0062] Another aspect of the present invention provides a composition for enhancing muscle strength, comprising, as an active ingredient, a compound represented by Formula 1, a pharmaceutically acceptable salt thereof, or a food-grade acceptable salt thereof. The composition for enhancing muscle strength can be used as a pharmaceutical composition or a food composition.

[0063] Muscle strength enhancement refers to an increase in muscle mass, an increase in muscle recovery, and a reduction in muscle fatigue. The muscle strength enhancement composition has the ability to differentiate myoblasts into muscle cells, thereby increasing muscle mass and ultimately the overall muscle mass, thereby reducing muscle fatigue. Furthermore, the rapid replacement of muscle cells enables early recovery from muscle damage. The muscle strength enhancement composition of the present invention can be used as feed or a feed additive.

[0064] Another aspect of the present invention provides a method for preventing or treating a muscle weakness-related condition, comprising administering to a subject a compound represented by Formula 1, or a pharmaceutically acceptable salt thereof, wherein the compound, the muscle weakness-related condition, and the subject are the same as those described above.

[0065] Another aspect of the present invention provides use of a compound of Formula 1 or a pharmaceutically acceptable salt thereof for preventing or treating a muscle weakness-related condition, wherein the compound and the muscle weakness-related condition are as described above.

[0066] Another aspect of the present invention provides use of a compound of Formula 1 or a pharmaceutically acceptable salt thereof for the preparation of a medicament for preventing or treating a muscle weakness-related condition, wherein the compound and the muscle weakness-related condition are as described above.

[0067] [Mode of Invention] The present invention will be described in more detail below with reference to examples. The following examples are intended to further illustrate the present invention and are not intended to limit the scope thereof.

[0068] Experimental Example 1 Confirmation of the effect of Alverine citrate on promoting myoblast differentiation Experimental Example 1.1. Cultivation of myoblast cell line C2Cl2 C2Cl2 (American Type Culture Collection, CRL-1772™) cells are a myoblast cell line derived from C3H mice and have been used to study myoblast differentiation. C2Cl2 cells were cultured in growth medium followed by differentiation medium. Here, DMEM supplemented with 10% fetal bovine serum was used as the growth medium (GM), and DMEM supplemented with 5% horse serum (HS) was used as the differentiation medium (DM).

[0069] Experimental Example 1.2. Promotion of myoblast differentiation To confirm the effect of alverine citrate on promoting myoblast differentiation, C2C12 cells were dispensed into the GM described in Experimental Example 1.1 and cultured for 24 hours. The C2C12 cells were then treated with DMSO, insulin, or alverine citrate to induce differentiation for three days. The cells were then observed for myotube differentiation and changes in myotube thickness and diameter using fluorescent staining with an antibody against myosin heavy chain (hereinafter referred to as MyHC). The DMSO, insulin, and alverine citrate used in this experiment were all purchased from Sigma-Aldrich. The insulin-treated group served as a positive control.

[0070] Specifically, C2C12 cells were grown in 6-well plates treated with GM as described in Experimental Example 1.1 at 5 x 10 cells per plate. 5 The cells were aliquoted at a concentration of 1 / 3 cell, and after 24 hours, the medium was replaced with DMEM supplemented with 5% HS to induce differentiation. The cells were then treated with DMSO, insulin (1.72 μM), or alverine citrate (0.01 μM, 0.1 μM, 1 μM, or 10 μM). After 3 days, the medium was removed, and the cells were washed with phosphate buffer (1x PBS), treated with paraformaldehyde (4%), and fixed for 15 minutes at room temperature. The cells were then washed three times with phosphate buffer (1x PBS), permeabilized with PBS containing 0.3% Triton X-100, and incubated for 10 minutes at room temperature.

[0071] After washing three times with phosphate buffer (1x PBS), PBST containing 2% bovine serum albumin (PBST containing 0.5% Tween 20) was added and incubated for 30 minutes to suppress nonspecific antibody binding. After washing three times with phosphate buffer (1x PBS), 100 μL of a 1:500 diluted primary antibody against MYH3 (SC-20641, Santa Cruz Biotechnology) was added and incubated for 1 hour at room temperature. After washing three times with phosphate buffer (1x PBS), 100 μL of a 1:5,000 diluted secondary antibody (goat anti-rabbit IgG-HRP) was added and incubated for 1 hour at room temperature. After 1 hour, for nuclear staining, the cells were washed three times with phosphate buffer (1x PBS) and treated with DAPI dye diluted in blocking buffer for 10 minutes at room temperature. After washing the coverslips three times with phosphate buffer (1X PBS), the absorbance of the washed coverslips was measured at 450 nm, and fluorescent images were taken under a fluorescence microscope. The anti-MyHC antibody-stained areas were analyzed using ImageJ (a Java-based image processing program).

[0072] The results showed that myoblasts treated with insulin or alverine citrate differentiated into myotubes more rapidly than myoblasts treated with DMSO alone. In particular, the higher the concentration of alverine citrate, the larger the diameter of the myotubes (Figures 1 and 2).

[0073] Experimental Example 2 Confirmation of the effect of Alverine citrate on muscle strength enhancement using normal mice To confirm the muscle-strengthening effect of alverine citrate, mice were administered alverine citrate and then tested for motor function, including grip strength, running, and balance control. After the motor function tests, muscle weight was measured. Specifically, 10-week-old C57BL / 6 male mice were orally administered 200 μL of alverine citrate at a daily dose of 17 mg / kg / day (AC-L), 50 mg / kg / day (AC-M), or 150 mg / kg / day (AC-H) for 4 weeks. These mouse groups were designated as the experimental groups (Figure 3). 10-week-old C57BL / 6 male mice were purchased from Daehan BioLink.

[0074] Experimental Example 2.1. Measurement of grip strength Grip strength was measured using a mouse grip strength meter (Bioseb, USA). Specifically, a mouse was placed on a metal grid connected to an instrument panel that monitors grip strength, and the mouse's grip strength was measured while pulling back by its tail. Five consecutive measurements were taken, and the average of the five measurements was calculated.

[0075] As a result, the grip strength of the mice in the experimental group was higher than that of the mice in the normal group. These results confirmed that Alverine citrate has a muscle strength-enhancing effect (Figure 4).

[0076] Experimental example 2.2. Driving ability test Running ability was measured using a treadmill specially designed for this experiment. First, an aversive stimulus was administered by applying an electrical stimulus at the starting point. Before measurement, mice were habituated for 10 minutes at 8 m / min. Each group of mice was run in a separate lane, and the time it took to run until exhaustion was recorded. Exhaustion was defined as when the mouse remained outside the lane for 10 seconds or more without running. The mouse was considered exhausted, and the time was recorded. This experiment could not be repeated with the same mouse. Mice were placed on the treadmill and the test started at 8 rpm, accelerating by 2 rpm every 10 minutes until the maximum speed of 20 rpm was reached. The lane inclination started at 0° and increased to 5° 30 minutes after the start.

[0077] The results showed that the running time of the experimental group mice was increased compared to the normal group mice, and a significant increase in running time was confirmed especially in the experimental group treated with Alverine citrate at 150 mg / kg / day (Figure 5).

[0078] Experimental Example 2.3. Balance adjustment test Balance control was measured using a rotarod test. The rotarod test apparatus consisted of four test zones, each with a 3 cm shaft diameter and a 9 cm lane width, five rotatable circular dividers with a diameter of 60 cm, and a round rod. The test started at a rotation speed of 10 rpm and accelerated to a maximum of 40 rpm over a 5-minute period. The time the mouse could hold on to the round rod within the rotarod apparatus without falling was recorded. After each test, the mouse was allowed to rest for 15 minutes, and a total of three tests were performed. The average of the three measurements was calculated.

[0079] The results showed that the mice in the experimental group clung to the rod for a longer time than the mice in the normal group, and that as the dose of Alverine citrate increased, the time the mice in the experimental group clung to the rod increased proportionally (Figure 6).

[0080] Experimental Example 2.4. Measurement of muscle weight For muscle weight measurements, the gastrocnemius (GA) and tibialis anterior (TA) muscles were removed from the hind legs of each group of mice and weighed. As a result, the muscle weights of the GA and TA of the experimental group mice were found to be increased compared to the control group mice, and in particular, the muscle weights of the GA and TA of the experimental group mice increased with increasing doses of alverine citrate (Figure 7).

[0081] Experimental Example 3 Confirmation of the muscle strengthening effect of Alverine citrate using sarcopenia-induced mice To confirm the muscle-strengthening effect of alverine citrate, sarcopenia-induced mice were administered alverine citrate and subjected to a running test. After the treadmill running test, muscle weight was measured. Specifically, the hind limbs of 10-week-old C57BL / 6 male mice were fixed using a surgical stapler (Autosuture Royal 35W stapler). Five days later, the staples were removed, and the mice were remobilized for three days. Running capacity was then measured. Alverine citrate was orally administered to mice at doses of 17 mg / kg / day (AC-L), 50 mg / kg / day (AC-M), or 150 mg / kg / day (AC-H) in a volume of 200 μL per mouse. These mice served as the experimental group. Untreated sarcopenia-induced mice served as the control group (Figure 8). Ten-week-old C57BL / 6 male mice were purchased from Daehan BioLink.

[0082] Experimental example 3.1. Driving ability test Running ability was measured using the same method as in Experimental Example 2.2. As a result, it was found that the running time of the control group mice was approximately 10 minutes shorter than that of the normal group mice. On the other hand, the running time of the experimental group mice increased in proportion to the administered concentration of Alverine citrate, and in particular, the running time of the experimental group that received an oral administration of Alverine at 150 mg / kg / day (AC-H) was longer than that of the normal group mice.

[0083] Experimental Example 3.2. Muscle weight measurement To measure muscle weight, the GA and TA muscles were removed from the hind limbs of each group of mice and weighed. The results showed that the weight of the GA and TA muscles in the control group was significantly reduced compared to the normal group. However, in the experimental group, the weight of the GA and TA muscles increased as the concentration of alverine citrate administered increased (Figure 10).

[0084] Experimental Example 4. Confirmation of the effect of 4-hydroxyalverine on promoting myoblast differentiation To confirm the effect of 4-hydroxyalverine on promoting myoblast differentiation, DMSO, insulin (1.72 μM), alverine citrate (0.01 μM, 0.1 μM, 1 μM, or 10 μM), and 4-hydroxyalverine (0.01 μM, 0.1 μM, 1 μM, or 10 μM) were administered in the same manner as in Experimental Example 1, and the differentiation into myotubes and changes in the thickness and diameter of the myotubes were observed. Here, the alverine and 4-hydroxyalverine are as shown in Table 1. [Table 1]

[0085] As a result, it was found that myoblasts treated with alverine citrate or 4-hydroxyalverine differentiated into myotubes more effectively than myoblasts treated with DMSO or insulin (Figures 11 and 12). When compared at the same concentrations, 4-hydroxyalverine had a more potent differentiation-promoting effect than alverine.

[0086] Experimental Example 5. Confirmation of the therapeutic effect of Alverine citrate and 4-hydroxyalverine on cachexia To confirm the therapeutic effects of alverine citrate and 4-hydroxyalverine on cachexia, an ex vivo approach was conducted to mimic the tumor growth environment by treating cancer cell-conditioned medium (CM). First, cancer cell CM was prepared using the C26 cancer cell line. RPMI 1640 medium supplemented with 10% fetal bovine serum was used as the cell growth medium (GM). The C26 cancer cell line was cultured in a 100 mm cell culture plate using cancer cell GM. The medium was removed when the cell confluency reached 90%. After washing with phosphate buffer (1X buffer), the prepared differentiation medium was treated as in Experimental Example 1. After 24 hours, the C26 cancer cell line CM was obtained and filtered using a bottle-top filter (Thermo, PES, 1 L) before use.

[0087] C2C12 cells were plated at 5 x 10 per well in the GM-treated 6-well plate described in Experiment 1.1.5 The cells were aliquoted at a concentration of 1000 cells / ml, and after 24 hours, the medium was replaced with MEM medium supplemented with 5% HS to induce differentiation. After 4 days, the differentiated myotubes were treated with differentiation medium supplemented with 33% CM to induce myotube atrophy for 3 days. The experimental group was treated with 1 μM alverine citrate (AC) and 4-hydroxyalverine (4HA) to evaluate their inhibitory effect on myotube atrophy. DMSO was used as a negative control, and ursolic acid (UA) was used as a positive control. Following the same method as in Experimental Example 1.2, fluorescent staining was performed using an antibody against MyHC, and the expression level of MyHC was measured.

[0088] As a result, it was found that myotubes in the negative control group were atrophied by CM, whereas treatment with alverine citrate or 4-hydroxyalverine inhibited myotube atrophy (Figures 13 and 14).

[0089] Example 1. Confirmation of the effect of alverine derivatives on promoting myoblast differentiation Example 1.1. Growth of the myoblast cell line C2Cl2 C2Cl2 (American Type Culture Collection, CRL-1772™) cells are a myoblast cell line derived from C3H mice and have been used to study myoblast differentiation. C2Cl2 cells were cultured in growth medium followed by differentiation medium. Here, DMEM supplemented with 10% fetal bovine serum was used as the growth medium (GM), and DMEM supplemented with 5% horse serum was used as the differentiation medium (DM).

[0090] Example 1.2. Promotion of differentiation of myoblast cell lines To confirm the effect of alverine derivatives on promoting myoblast differentiation, C2C12 cells were cultured in the GM described in Example 1.1 for 24 hours. Subsequently, C2C12 cells were treated with DMSO (Sigma-Aldrich), insulin, alverine (Sigma-Aldrich), or 27 alverine derivatives at a concentration of 1 μM each, and differentiation was induced for 4 days. Then, myotube differentiation and changes in myotube thickness and diameter were monitored by fluorescent staining using an antibody against MyHC. The 27 alverine derivatives were designed and synthesized by the Korea Institute of Bioscience and JD Bioscience upon request. Alverine and the 27 alverine derivatives 1 to 27 used in the experiment are listed in Table 2 below. [Table 2] TIFF0007734144000006.tif73148

[0091] Specifically, 5 × 10 C2C12 cells were plated in a 6-well plate treated with GM as described in Example 1.1. 5 The cells were aliquoted at a concentration of 1000 cells / ml, and after 24 hours, the medium was replaced with DMEM supplemented with 5% HS to induce differentiation. The cells were then treated with 1 μM DMSO, alverine, or 27 alverine derivatives. After 4 days, the medium was removed, washed with phosphate buffer (1x PBS), and treated with paraformaldehyde (4%) for 15 minutes at room temperature. After washing three times with phosphate buffer (1x PBS), the cells were treated with permeabilization buffer (PBS containing 0.3% Triton X-100) and incubated for 10 minutes at room temperature.

[0092] After washing three times with phosphate buffer (1x PBS), PBST containing 2% bovine serum albumin (PBST with 0.5% Tween 20) was added and incubated for 30 minutes to suppress nonspecific antibody binding. After washing three times with phosphate buffer (1x PBS), 100 μL of a 1:500 diluted primary antibody against MYH3 (SC-20641, Santa Cruz Biotechnology) was added and incubated for 1 hour at room temperature. After washing three times with phosphate buffer (1x PBS), 100 μL of a 1:5,000 diluted secondary antibody (goat anti-rabbit IgG-HRP) was added and incubated for 1 hour at room temperature. After 1 hour, for nuclear staining, the cells were washed three times with phosphate buffer (1x PBS) and treated with DAPI dye diluted in blocking buffer for 10 minutes at room temperature. After that, the coverslips were washed three times with phosphate buffer solution (1X PBS), and the absorbance of the washed coverslips was measured at a wavelength of 450 nm, and fluorescent images were taken using a fluorescent microscope.

[0093] As a result, it was confirmed that compared to myoblasts treated with DMSO alone, myoblasts treated with each of the 27 types of alverine derivatives also promoted differentiation into myotubes, just like myoblasts treated with alverine alone.

Claims

1. 1) 4-(3-ethyl(3-phenylpropyl)amino)propyl)aniline; 2) N-ethyl-3-(4-methoxyphenyl)-N-(3-phenylpropyl)propan-1-amine; 3) N-ethyl-3-phenyl-N-(3-(p-tolyl)propyl)propan-1-amine; 4) 3-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 7) 4-(3-(methyl(3-phenylpropyl)amino)propyl)phenol; 8) 4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)aniline; 9) N-(4-(3-((3-)4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 10) 4-(3-(ethyl(phenethyl)amino)propyl)phenol; 11) 4-(3-(ethyl(3-phenylpropyl)amino)propyl)-2-fluorophenol; 12) 2-bromo-4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 13) 1-(4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)-3-phenylurea; 14) Ethyl(4-phenylbutyl)(3-phenylpropyl)amine; 15) Ethylbis(4-phenylbutyl)amine; 16) (4-phenylbutyl)(3-phenylpropyl)propylamine; 17) 3-(4-butoxyphenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 18) 3-(4-(but-3-en-1-yloxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 19) 3-(4-(4-bromobutoxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 20) 4-(4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenoxy)butan-1-amine; 21) 4-(3-(ethyl(3-(4-methoxyphenyl)propyl)amino)propyl)-2-fluorophenol; 22) 4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)aniline; 23) N-(4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 24) 3-(4-(benzyloxy)-3-fluorophenyl)-N-methyl-N-(3-phenylpropyl)propan-1-amine; 25) 4-(3-(ethyl(3-(p-tolyl)propyl)amino)propyl)-2-fluorophenol; 26) N-ethyl-3-phenyl-N-(3-(4-(3-phenylpropoxy)phenyl)propyl)propan-1-amine; 27) N-ethyl-3-phenyl-N-(3-(4-((5-phenylpentyl)oxy)phenyl)propyl)propan-1-amine; and 29) 4-[3-[ethyl(3-phenylpropyl)amino]propyl]phenol or a pharmaceutically acceptable salt thereof, selected from the group consisting of:

2. 1) 4-(3-ethyl(3-phenylpropyl)amino)propyl)aniline; 2) N-ethyl-3-(4-methoxyphenyl)-N-(3-phenylpropyl)propan-1-amine; 3) N-ethyl-3-phenyl-N-(3-(p-tolyl)propyl)propan-1-amine; 4) 3-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 5) N-methyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; 6) 4,4'-((ethylazanediyl))bis(propane-3,1-diyl))diphenol; 7) 4-(3-(methyl(3-phenylpropyl)amino)propyl)phenol; 8) 4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)aniline; 9) N-(4-(3-((3-)4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 10) 4-(3-(ethyl(phenethyl)amino)propyl)phenol; 11) 4-(3-(ethyl(3-phenylpropyl)amino)propyl)-2-fluorophenol; 12) 2-bromo-4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 13) 1-(4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)-3-phenylurea; 14) Ethyl(4-phenylbutyl)(3-phenylpropyl)amine; 15) Ethylbis(4-phenylbutyl)amine; 16) (4-phenylbutyl)(3-phenylpropyl)propylamine; 17) 3-(4-butoxyphenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 18) 3-(4-(but-3-en-1-yloxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 19) 3-(4-(4-bromobutoxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 20) 4-(4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenoxy)butan-1-amine; 21) 4-(3-(ethyl(3-(4-methoxyphenyl)propyl)amino)propyl)-2-fluorophenol; 22) 4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)aniline; 23) N-(4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 24) 3-(4-(benzyloxy)-3-fluorophenyl)-N-methyl-N-(3-phenylpropyl)propan-1-amine; 25) 4-(3-(ethyl(3-(p-tolyl)propyl)amino)propyl)-2-fluorophenol; 26) N-ethyl-3-phenyl-N-(3-(4-(3-phenylpropoxy)phenyl)propyl)propan-1-amine; 27) N-ethyl-3-phenyl-N-(3-(4-((5-phenylpentyl)oxy)phenyl)propyl)propan-1-amine; 28) N-ethyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; and 29) 4-[3-[ethyl(3-phenylpropyl)amino]propyl]phenol A pharmaceutical composition for preventing or treating a condition associated with muscle weakness, comprising, as an active ingredient, a compound selected from the group consisting of: or a pharmaceutically acceptable salt thereof.

3. 3. The pharmaceutical composition of claim 2, wherein the pharmaceutically acceptable salt is a citrate salt.

4. 3. The pharmaceutical composition of claim 2, wherein the muscle weakness-related condition is sarcopenia, muscle atrophy, muscular dystrophy, or cachexia.

5. 1) 4-(3-ethyl(3-phenylpropyl)amino)propyl)aniline; 2) N-ethyl-3-(4-methoxyphenyl)-N-(3-phenylpropyl)propan-1-amine; 3) N-ethyl-3-phenyl-N-(3-(p-tolyl)propyl)propan-1-amine; 4) 3-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 5) N-methyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; 6) 4,4'-((ethylazanediyl))bis(propane-3,1-diyl))diphenol; 7) 4-(3-(methyl(3-phenylpropyl)amino)propyl)phenol; 8) 4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)aniline; 9) N-(4-(3-((3-)4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 10) 4-(3-(ethyl(phenethyl)amino)propyl)phenol; 11) 4-(3-(ethyl(3-phenylpropyl)amino)propyl)-2-fluorophenol; 12) 2-bromo-4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 13) 1-(4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)-3-phenylurea; 14) Ethyl(4-phenylbutyl)(3-phenylpropyl)amine; 15) Ethylbis(4-phenylbutyl)amine; 16) (4-phenylbutyl)(3-phenylpropyl)propylamine; 17) 3-(4-butoxyphenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 18) 3-(4-(but-3-en-1-yloxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 19) 3-(4-(4-bromobutoxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 20) 4-(4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenoxy)butan-1-amine; 21) 4-(3-(ethyl(3-(4-methoxyphenyl)propyl)amino)propyl)-2-fluorophenol; 22) 4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)aniline; 23) N-(4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 24) 3-(4-(benzyloxy)-3-fluorophenyl)-N-methyl-N-(3-phenylpropyl)propan-1-amine; 25) 4-(3-(ethyl(3-(p-tolyl)propyl)amino)propyl)-2-fluorophenol; 26) N-ethyl-3-phenyl-N-(3-(4-(3-phenylpropoxy)phenyl)propyl)propan-1-amine; 27) N-ethyl-3-phenyl-N-(3-(4-((5-phenylpentyl)oxy)phenyl)propyl)propan-1-amine; 28) N-ethyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; and 29) 4-[3-[ethyl(3-phenylpropyl)amino]propyl]phenol A composition for promoting myoblast differentiation, comprising, as an active ingredient, a compound or a pharmaceutically acceptable salt thereof selected from the group consisting of:

6. 1) 4-(3-ethyl(3-phenylpropyl)amino)propyl)aniline; 2) N-ethyl-3-(4-methoxyphenyl)-N-(3-phenylpropyl)propan-1-amine; 3) N-ethyl-3-phenyl-N-(3-(p-tolyl)propyl)propan-1-amine; 4) 3-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 5) N-methyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; 6) 4,4'-((ethylazanediyl))bis(propane-3,1-diyl))diphenol; 7) 4-(3-(methyl(3-phenylpropyl)amino)propyl)phenol; 8) 4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)aniline; 9) N-(4-(3-((3-)4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 10) 4-(3-(ethyl(phenethyl)amino)propyl)phenol; 11) 4-(3-(ethyl(3-phenylpropyl)amino)propyl)-2-fluorophenol; 12) 2-bromo-4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 13) 1-(4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)-3-phenylurea; 14) Ethyl(4-phenylbutyl)(3-phenylpropyl)amine; 15) Ethylbis(4-phenylbutyl)amine; 16) (4-phenylbutyl)(3-phenylpropyl)propylamine; 17) 3-(4-butoxyphenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 18) 3-(4-(but-3-en-1-yloxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 19) 3-(4-(4-bromobutoxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 20) 4-(4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenoxy)butan-1-amine; 21) 4-(3-(ethyl(3-(4-methoxyphenyl)propyl)amino)propyl)-2-fluorophenol; 22) 4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)aniline; 23) N-(4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 24) 3-(4-(benzyloxy)-3-fluorophenyl)-N-methyl-N-(3-phenylpropyl)propan-1-amine; 25) 4-(3-(ethyl(3-(p-tolyl)propyl)amino)propyl)-2-fluorophenol; 26) N-ethyl-3-phenyl-N-(3-(4-(3-phenylpropoxy)phenyl)propyl)propan-1-amine; 27) N-ethyl-3-phenyl-N-(3-(4-((5-phenylpentyl)oxy)phenyl)propyl)propan-1-amine; 28) N-ethyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; and 29) 4-[3-[ethyl(3-phenylpropyl)amino]propyl]phenol A method for promoting myoblast differentiation, comprising treating myoblasts ex vivo with a compound selected from the group consisting of:

7. 1) 4-(3-ethyl(3-phenylpropyl)amino)propyl)aniline; 2) N-ethyl-3-(4-methoxyphenyl)-N-(3-phenylpropyl)propan-1-amine; 3) N-ethyl-3-phenyl-N-(3-(p-tolyl)propyl)propan-1-amine; 4) 3-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 5) N-methyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; 6) 4,4'-((ethylazanediyl))bis(propane-3,1-diyl))diphenol; 7) 4-(3-(methyl(3-phenylpropyl)amino)propyl)phenol; 8) 4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)aniline; 9) N-(4-(3-((3-)4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 10) 4-(3-(ethyl(phenethyl)amino)propyl)phenol; 11) 4-(3-(ethyl(3-phenylpropyl)amino)propyl)-2-fluorophenol; 12) 2-bromo-4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 13) 1-(4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)-3-phenylurea; 14) Ethyl(4-phenylbutyl)(3-phenylpropyl)amine; 15) Ethylbis(4-phenylbutyl)amine; 16) (4-phenylbutyl)(3-phenylpropyl)propylamine; 17) 3-(4-butoxyphenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 18) 3-(4-(but-3-en-1-yloxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 19) 3-(4-(4-bromobutoxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 20) 4-(4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenoxy)butan-1-amine; 21) 4-(3-(ethyl(3-(4-methoxyphenyl)propyl)amino)propyl)-2-fluorophenol; 22) 4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)aniline; 23) N-(4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 24) 3-(4-(benzyloxy)-3-fluorophenyl)-N-methyl-N-(3-phenylpropyl)propan-1-amine; 25) 4-(3-(ethyl(3-(p-tolyl)propyl)amino)propyl)-2-fluorophenol; 26) N-ethyl-3-phenyl-N-(3-(4-(3-phenylpropoxy)phenyl)propyl)propan-1-amine; 27) N-ethyl-3-phenyl-N-(3-(4-((5-phenylpentyl)oxy)phenyl)propyl)propan-1-amine; 28) N-ethyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; and 29) 4-[3-[ethyl(3-phenylpropyl)amino]propyl]phenol 1. A method for producing myotubes, comprising treating myoblasts ex vivo with a compound selected from the group consisting of: or a pharmaceutically acceptable salt thereof, to cause differentiation of the myoblasts.

8. 1) 4-(3-ethyl(3-phenylpropyl)amino)propyl)aniline; 2) N-ethyl-3-(4-methoxyphenyl)-N-(3-phenylpropyl)propan-1-amine; 3) N-ethyl-3-phenyl-N-(3-(p-tolyl)propyl)propan-1-amine; 4) 3-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 5) N-methyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; 6) 4,4'-((ethylazanediyl))bis(propane-3,1-diyl))diphenol; 7) 4-(3-(methyl(3-phenylpropyl)amino)propyl)phenol; 8) 4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)aniline; 9) N-(4-(3-((3-)4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 10) 4-(3-(ethyl(phenethyl)amino)propyl)phenol; 11) 4-(3-(ethyl(3-phenylpropyl)amino)propyl)-2-fluorophenol; 12) 2-bromo-4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 13) 1-(4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)-3-phenylurea; 14) Ethyl(4-phenylbutyl)(3-phenylpropyl)amine; 15) Ethylbis(4-phenylbutyl)amine; 16) (4-phenylbutyl)(3-phenylpropyl)propylamine; 17) 3-(4-butoxyphenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 18) 3-(4-(but-3-en-1-yloxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 19) 3-(4-(4-bromobutoxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 20) 4-(4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenoxy)butan-1-amine; 21) 4-(3-(ethyl(3-(4-methoxyphenyl)propyl)amino)propyl)-2-fluorophenol; 22) 4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)aniline; 23) N-(4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 24) 3-(4-(benzyloxy)-3-fluorophenyl)-N-methyl-N-(3-phenylpropyl)propan-1-amine; 25) 4-(3-(ethyl(3-(p-tolyl)propyl)amino)propyl)-2-fluorophenol; 26) N-ethyl-3-phenyl-N-(3-(4-(3-phenylpropoxy)phenyl)propyl)propan-1-amine; 27) N-ethyl-3-phenyl-N-(3-(4-((5-phenylpentyl)oxy)phenyl)propyl)propan-1-amine; 28) N-ethyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; and 29) 4-[3-[ethyl(3-phenylpropyl)amino]propyl]phenol A food composition for preventing or alleviating a condition associated with muscle weakness, comprising a compound selected from the group consisting of: or a nutrient-based acceptable salt thereof.

9. The food composition according to claim 8, wherein the muscle weakness-related condition is sarcopenia, muscle atrophy, muscular dystrophy, or cachexia.

10. 1) 4-(3-ethyl(3-phenylpropyl)amino)propyl)aniline; 2) N-ethyl-3-(4-methoxyphenyl)-N-(3-phenylpropyl)propan-1-amine; 3) N-ethyl-3-phenyl-N-(3-(p-tolyl)propyl)propan-1-amine; 4) 3-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 5) N-methyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; 6) 4,4'-((ethylazanediyl))bis(propane-3,1-diyl))diphenol; 7) 4-(3-(methyl(3-phenylpropyl)amino)propyl)phenol; 8) 4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)aniline; 9) N-(4-(3-((3-)4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 10) 4-(3-(ethyl(phenethyl)amino)propyl)phenol; 11) 4-(3-(ethyl(3-phenylpropyl)amino)propyl)-2-fluorophenol; 12) 2-bromo-4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 13) 1-(4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)-3-phenylurea; 14) Ethyl(4-phenylbutyl)(3-phenylpropyl)amine; 15) Ethylbis(4-phenylbutyl)amine; 16) (4-phenylbutyl)(3-phenylpropyl)propylamine; 17) 3-(4-butoxyphenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 18) 3-(4-(but-3-en-1-yloxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 19) 3-(4-(4-bromobutoxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 20) 4-(4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenoxy)butan-1-amine; 21) 4-(3-(ethyl(3-(4-methoxyphenyl)propyl)amino)propyl)-2-fluorophenol; 22) 4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)aniline; 23) N-(4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 24) 3-(4-(benzyloxy)-3-fluorophenyl)-N-methyl-N-(3-phenylpropyl)propan-1-amine; 25) 4-(3-(ethyl(3-(p-tolyl)propyl)amino)propyl)-2-fluorophenol; 26) N-ethyl-3-phenyl-N-(3-(4-(3-phenylpropoxy)phenyl)propyl)propan-1-amine; 27) N-ethyl-3-phenyl-N-(3-(4-((5-phenylpentyl)oxy)phenyl)propyl)propan-1-amine; 28) N-ethyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; and 29) 4-[3-[ethyl(3-phenylpropyl)amino]propyl]phenol A composition for enhancing muscle strength, comprising, as an active ingredient, a compound or a pharmaceutically acceptable salt thereof selected from the group consisting of:

11. For the preparation of a medicament for preventing or treating a muscle weakness-related condition, 1) 4-(3-ethyl(3-phenylpropyl)amino)propyl)aniline; 2) N-ethyl-3-(4-methoxyphenyl)-N-(3-phenylpropyl)propan-1-amine; 3) N-ethyl-3-phenyl-N-(3-(p-tolyl)propyl)propan-1-amine; 4) 3-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 5) N-methyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; 6) 4,4'-((ethylazanediyl))bis(propane-3,1-diyl))diphenol; 7) 4-(3-(methyl(3-phenylpropyl)amino)propyl)phenol; 8) 4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)aniline; 9) N-(4-(3-((3-)4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 10) 4-(3-(ethyl(phenethyl)amino)propyl)phenol; 11) 4-(3-(ethyl(3-phenylpropyl)amino)propyl)-2-fluorophenol; 12) 2-bromo-4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenol; 13) 1-(4-(3-((3-(4-(benzyloxy)phenyl)propyl)(ethyl)amino)propyl)phenyl)-3-phenylurea; 14) Ethyl(4-phenylbutyl)(3-phenylpropyl)amine; 15) Ethylbis(4-phenylbutyl)amine; 16) (4-phenylbutyl)(3-phenylpropyl)propylamine; 17) 3-(4-butoxyphenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 18) 3-(4-(but-3-en-1-yloxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 19) 3-(4-(4-bromobutoxy)phenyl)-N-ethyl-N-(3-phenylpropyl)propan-1-amine; 20) 4-(4-(3-(ethyl(3-phenylpropyl)amino)propyl)phenoxy)butan-1-amine; 21) 4-(3-(ethyl(3-(4-methoxyphenyl)propyl)amino)propyl)-2-fluorophenol; 22) 4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)aniline; 23) N-(4-(3-((3-(4-(benzyloxy)-3-fluorophenyl)propyl)(ethyl)amino)propyl)phenyl)acetamide; 24) 3-(4-(benzyloxy)-3-fluorophenyl)-N-methyl-N-(3-phenylpropyl)propan-1-amine; 25) 4-(3-(ethyl(3-(p-tolyl)propyl)amino)propyl)-2-fluorophenol; 26) N-ethyl-3-phenyl-N-(3-(4-(3-phenylpropoxy)phenyl)propyl)propan-1-amine; 27) N-ethyl-3-phenyl-N-(3-(4-((5-phenylpentyl)oxy)phenyl)propyl)propan-1-amine; 28) N-ethyl-3-phenyl-N-(3-phenylpropyl)propan-1-amine; and 29) 4-[3-[ethyl(3-phenylpropyl)amino]propyl]phenol 10. Use of a compound selected from the group consisting of: or a pharmaceutically acceptable salt thereof.

Images