Peptides, derivatives thereof, and use of same

Abstract

The present invention belongs to the field of pharmacy. Provided are peptides, derivatives thereof, and the use of same. The peptides and the derivatives thereof are compounds as shown in formula 1 or pharmaceutically acceptable salts thereof, wherein aa represents natural or unnatural amino acids, the configurations thereof being D- or L-configuration; 4-7 represents that the peptides can be formed by amide bond condensation of four to seven amino acids; R is hydrogen, or glycosyl, or PEG chains having different lengths, or acetyl; in addition, the peptide sequences at least contain two to three basic natural or unnatural amino acids. The compounds have the effects of promoting post-stroke or post-traumatic neurofunction restoration and treating affective disorder diseases. Meanwhile, because of a unique action mechanism of the compounds, the compounds can also be used for preparing drugs for treating Alzheimer's disease and various neurodegenerative diseases. R-(aa)4-7-NH2 (formula 1).

Description

A class of peptides and their derivatives and applications Technical Field

[0001] The present invention belongs to the pharmaceutical field and provides a class of peptides and derivatives thereof and applications. Background Art

[0002] Stroke is a disease with high mortality and disability rates, seriously endangering human health (Circulation, 2017, 135:759-771). In recent years, with the application of thrombolysis and interventional thrombectomy techniques, as well as the promotion of stroke diagnosis and treatment guidelines and expert consensus, acute mortality rates have decreased, but the incidence of stroke continues to rise. The rising incidence and declining mortality have made stroke an increasingly chronic disease, while disability rates remain high. However, there are currently no clinically effective drugs to promote functional recovery after stroke. Studies have shown that upregulating neural network excitability can promote post-stroke damage repair (Theranostics, 2021, 11:3760-3780; Nat. Rev. Neurosci., 2021, 22:38-53). Gamma-aminobutyric acid (GABA) is a key neurotransmitter regulating neural network excitability (Nat. Rev. Neurosci., 2005, 6:215-229). GABA and extrasynaptic ionotropic GABA receptors (γ-aminobutyric acid type A receptor, GABA A The binding of GABA to GABA R) will produce GABA tonic inhibitory current, thereby reducing the excitability of the neural network; GABA and GABA in the synapse ABinding to GABA R generates a phasic GABA inhibitory current, thereby suppressing local neuronal hyperexcitability and mediating beta-wave oscillations in the neural network. Both play a crucial role in regulating neural network excitability during the subacute and recovery phases of stroke and promoting injury repair (Nature, 2010, 468:305-309; J. Neurosci., 2017, 37:6712-6728; Brain, 2016, 139:468-480, Cell Rep., 2023, 42:112-294). In experimental animal models of stroke, reducing GABA tonic inhibitory currents or increasing GABA phasic inhibitory currents have been shown to promote functional recovery after stroke (Nature, 2010, 468:305-309; Brain, 2016, 139:468-480). However, simply reducing GABA tonic inhibitory current may lead to excessive excitability of neural networks, posing a risk of epilepsy (Nature, 2010, 468: 176-177), and by antagonizing extrasynaptic α5-type GABA A The drug S44819, which reduces GABA tonic inhibitory currents, did not produce positive results in a multicenter randomized double-blind clinical trial (Lancet Neurol., 2020, 19: 226-233). Drugs that increase GABA phasic inhibitory currents alone, such as benzodiazepines, can produce sedation, and long-term administration can lead to the development of tolerance, as well as side effects such as continuous abuse and withdrawal symptoms (Science, 2009, 325: 490-493). Therefore, exploring the regulatory mechanism of GABA currents and finding targets for simultaneous reduction of GABA tonic inhibitory currents and enhancement of GABA phasic inhibitory currents for intervention are expected to obtain safe and effective therapeutic drugs that promote the repair of stroke damage.

[0003] GAT-1 is distributed in the presynaptic membrane and extrasynaptic compartments of inhibitory neurons, responsible for intrasynaptic and extrasynaptic GABA reuptake, respectively, thereby simultaneously regulating GABA phasic and tonic inhibitory currents (J. Neurochem., 2008, 105:1781-1793). Enhancing GAT-1's transport function would simultaneously reduce both GABA tonic and phasic inhibitory currents, making it difficult to achieve the aforementioned goal. GAT-1 interacts with the SNARE family protein Syntaxin 1A in the presynaptic compartments of inhibitory neurons to form the GAT-1-yntaxin 1A complex, thereby downregulating GAT-1 function (Nat. Neurosci., 2000, 3:998-1003). Blocking GAT-1-yntaxin 1A coupling would enhance GAT-1's transport function and increase GABA reuptake. The H3 domain of Syntaxin 1A is a key motif for its interaction with GAT-1 (J. Neurosci., 2004, 24:4082-4087). Syntaxin 1A also interacts with other SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) family proteins through its H3 domain, participating in the regulation of inhibitory synaptic transmission (Neuron, 2014, 82:1088-1100; J. Neurosci., 2001, 21:9142-9150; J. Biol. Chem., 2001, 276:13273-13282). Given the competitive interaction between GAT-1 and other SNARE family proteins and Syntaxin 1A, GAT-1-Syntaxin 1A coupling can also inhibit GABAergic synaptic transmission. Therefore, blocking GAT-1-Syntaxin 1A coupling will enhance GAT-1's ability to uptake extracellular GABA, reducing GABA tonic inhibitory currents while increasing phasic inhibitory currents, achieving the above goals. Furthermore, brain-derived neurotrophic factor (BDNF) mediates the plasticity of neural structure and function, playing a crucial role in the repair of central nervous system injuries such as stroke and brain trauma (Cell Rep., 2015, 11:1054-1066; J. Cereb. Blood Flow Metab., 2017, 37:1030-1045).

[0004] Mood disorders are a group of psychological diseases with anxiety and depression as the main clinical manifestations (Nat.Med., 2014, 20:1050-1054; Science, 2022, 378:390-398). However, the anti-anxiety and anti-depressant drugs currently used in clinical practice are slow to take effect. Therefore, the development of fast-acting anti-anxiety and anti-depressant drugs is of great significance. A large number of experimental research results suggest that GABA system dysfunction is an important mechanism for the occurrence of mood disorders (Mol.Psychiatry., 2003, 8:721-737,715). Extrasynaptic GABA A R is mainly GABA containing α5 subunit A R(α5-GABA A R), α5-GABA A GABA R selective antagonists can reduce GABA tonic inhibitory currents, increase neuronal excitability, and thus exert rapid antidepressant effects (Neuropsychopharmacology, 2015, 40: 2499-2509). A GABA R agonists can enhance intrasynaptic GABA phasic inhibitory currents, exerting anxiolytic and antidepressant effects (Mol. Psychiatry, 2003, 8:721-737, 715). These studies suggest that both reducing and enhancing GABA phasic inhibitory currents have antidepressant and anxiolytic effects. Therefore, it is hypothesized that simultaneously reducing and enhancing GABA phasic inhibitory currents will produce even better antidepressant and anxiolytic effects. Drugs that block GAT-1-Syntaxin-1A coupling can achieve this goal. Furthermore, BDNF has both anxiolytic and antidepressant effects (Mol. Psychiatry, 2005, 10:345-352). Chronic unpredictable mild stress (CUMS) is a classic model for inducing anxiety and depression (Nat. Med., 2014, 20:1050-1054; Science, 2022, 378:390-398).

[0005] Alzheimer's disease (AD) is a common neurodegenerative disease characterized by memory loss (Brain Pathol., 2023, 33:e13129). However, there are currently no effective clinical treatments. Experimental studies suggest that GABA tonic inhibitory currents are a key pathogenic mechanism of AD, and reducing GABA tonic inhibitory currents can improve cognitive impairment in AD animal models (Nat. Commun., 2014, 5:4159). Abnormal rhythmic oscillations in neural networks are also a key pathogenic factor in AD, and increasing GABA phasic inhibitory currents can modulate these rhythmic oscillations (Nat. Rev. Neurosci., 2005, 6:215-229; Brain Pathol., 2023, 33:e13129). The neurotrophic factor BDNF can improve cognitive impairment caused by Alzheimer's disease (Science, 2018, 361:eaan8821).

[0006] Summary of the Invention

[0007] To address the shortcomings of the existing technology, the first objective of the present invention is to provide a class of peptides and their derivatives. These drugs are most notably effective in promoting neurological recovery after stroke or trauma, as well as treating affective disorders. Furthermore, due to their unique mechanism of action, these drugs can also be used to prepare drugs for treating Alzheimer's disease (AD) and various neurodegenerative diseases.

[0008] The second object of the present invention is to provide the use of the peptide and its derivatives described above.

[0009] The technical solution adopted by the present invention to solve the technical problem is:

[0010] In a first aspect, the present invention protects a peptide and its derivatives or pharmaceutically acceptable salts thereof as shown in Formula 1:

[0011] R-(aa) 4～7 -NH2

[0012] Formula 1

[0013] in,

[0014] aa is a natural or unnatural amino acid, which may be in the D- or L-configuration;

[0015] The polypeptide is composed of 4 to 7 amino acids condensed through amide bonds;

[0016] Preferably, the polypeptide sequence contains at least 2 to 3 basic natural or unnatural amino acids;

[0017] Natural amino acids can be the 20 common protein-constituting amino acids, such as glycine, alanine, valine, leucine, isoleucine, methionine (methionine), proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, and histidine, among which alanine, valine, leucine, isoleucine, methionine, tryptophan, tyrosine, phenylalanine, lysine, and arginine are preferred;

[0018] Unnatural amino acids include, but are not limited to, phenylalanine, tyrosine, tryptophan, 1-naphthylalanine, 2-naphthylalanine, 3-aminopropionic acid, 4-aminobutyric acid, 5-aminopentanoic acid, 6-aminohexanoic acid, etc., substituted with alkyl or halogen on the aromatic ring; or ornithine, 2-pyridylalanine, 3-pyridylalanine, 4-pyridylalanine, 2,4-diaminobutyric acid, N-methyllysine, selenocysteine, pyrrolysine, etc. Among them, 2,6-dimethyltyrosine, 3,5-dimethyltyrosine, 2-ethyl-6-methyltyrosine, 2,3,5,6-tetramethyltyrosine, 2-isopropyl-6-methyltyrosine, 2,3,5-trimethyltyrosine, 2,3,6-trimethyltyrosine, 2,6-dimethylphenylalanine, 2,4,6-trimethylphenylalanine, cyclohexylalanine, cyclohexylglycine, 1-naphthylalanine, 2-naphthylalanine, ornithine, 4-pyridylalanine, etc. are preferred;

[0019] R is hydrogen or a sugar group or a PEG chain of varying lengths or an acetyl group;

[0020] When the R group is PEG, its molecular weight is 200 to 2000, preferably 1000;

[0021] When the R group is a saccharide, the saccharide is selected from a monosaccharide, a polysaccharide, or a derivatized monosaccharide or polysaccharide; specifically, it can be glucose, mannose, galactose, allose, altrose, gulose, idose, talose, ribose, xylose, arabinose, lyxose, etc., preferably glucose, galactose, ribose, arabinose, and modified derivatives of the above sugars and polysaccharides;

[0022] When the R group is a sugar group, the aldehyde group of the sugar can be directly condensed with the amino group at the N-terminus of the peptide to obtain a glycopeptide containing at least the following three forms:

[0023] Alternatively, the N-terminus of the peptide may be first derivatized with H2N-(CH2)n-COOH (n=1-6), and then the sugar may be condensed with the amino group of the derivatized peptide; alternatively, sugar amine may be first reacted with HOOC-(CH2)n-COOH (n=1-6) to generate sugar-NH-CO-(CH2)n-COOH (n=1-6), and then its carboxyl group may be condensed with the N-terminal amino group of the peptide to form a connection; sugars may also be linked to sugars through glycosidic bonds such as C-, N-, O-, and S-, via the N-terminal amino acid side chain group.

[0024] The present invention also protects a class of peptides and their derivatives, specifically as follows:

[0025] The inventors discovered that during the subacute phase of stroke, GAT-1-Syntaxin 1A coupling significantly increases in the peri-infarct region, leading to dysfunctional GAT-1 GABA reuptake and SNARE-mediated vesicle release. The polypeptides and their derivatives of the present invention, acting as Syntaxin1A-GAT-1 uncouplers / coupling blockers, can block GAT-1-Syntaxin 1A coupling, reversing ischemia-induced vesicle release impairment and GAT-1 GABA reuptake dysfunction, thereby improving post-stroke motor and cognitive dysfunction (Figures 1-8).

[0026] The inventors have observed that Syntaxin 1A-GAT-1 uncouplers can promote BDNF release. Therefore, GAT-1-Syntaxin 1A coupling is a new target for functional recovery after stroke, and GAT-1-Syntaxin 1A coupling blockers may become novel mechanistic drugs that promote functional recovery after stroke.

[0027] The inventors discovered that CUMS significantly increases GAT-1-Syntaxin-1A coupling in the hippocampus of experimental animals with anxiety and depression. Blocking GAT-1-Syntaxin-1A coupling can produce rapid antidepressant and anxiolytic effects (Figures 9-10). GAT-1-Syntaxin-1A uncouplers reduce GABA tonic inhibition, enhance GABA phasic inhibition, and promote BDNF release. Therefore, GAT-1-Syntaxin 1A coupling is a new target for rapid antidepressant and anxiolytic effects, and GAT-1-Syntaxin 1A coupling blockers may become novel, rapid antidepressant and anxiolytic drugs.

[0028] The inventors observed that Syntaxin 1A-GAT-1 uncoupling has a triple mechanism of promoting BDNF release, reducing GABA tonic inhibitory current, and increasing GABA phasic inhibitory current, which may also be of great significance for the drug treatment of AD-related diseases.

[0029] Preferably, a class of peptides and their derivatives of the present invention are selected from ZLQ-0, ZLQ-1, ZLQ-2, ZLQ-3, ZLQ-4, ZLQ-5, ZLQ-6, ZLQ-7, ZLQ-8, ZLQ-10, ZLQ-11, ZLQ-12, ZLQ-13, ZLQ-14, ZLQ-15, ZLQ-16, ZLQ-17, ZLQ-18, ZLQ-20 or ZLQ-21.

[0030] The compounds provided by the present invention also include pharmaceutically acceptable equivalents of the aforementioned compounds or a mixture of two or more thereof.

[0031] Preferably, the pharmaceutically acceptable equivalents of the compounds provided by the present invention may include pharmaceutically acceptable salts, hydrates, solvent mixtures, metabolites or prodrugs, or fusion peptides fused with peptide sequences solely for the purpose of penetrating cell membranes, blood-brain barriers, etc.

[0032] The compounds provided herein are pharmaceutically acceptable equivalents, and pharmaceutically acceptable salts include, but are not limited to, non-toxic inorganic and organic acid addition salts, such as hydrochloride, hydrobromide, nitrate, perchlorate, phosphate, sulfate, format, acetate, aconate, ascorbate, benzenesulfonate, benzoate, cinnamate, citrate, heptanoate, fumarate, glutamate, glycolate, lactate, maleate, malonate, mandelate, methanesulfonate, naphthalene-2sulfonate, phthalate, salicylate, sorbate, stearate, succinate, tartrate, p-toluenesulfonate, and the like.

[0033] The compounds of the present invention or pharmaceutically acceptable salts thereof can also be prepared into various preparations, including but not limited to injections, tablets, sprays, capsules, nasal drops, lyophilized powders, oral solutions, and the like.

[0034] Preferably, among the pharmaceutically acceptable equivalents of the compounds provided herein, prodrugs refer to derivatives of the compounds of the present invention that undergo biotransformation, such as metabolism, before exhibiting their pharmacological effects. Prodrugs may improve chemical stability, enhance patient acceptance and compliance, improve bioavailability, prolong duration of action, improve organ or tissue selectivity, improve formulations such as enhanced sustained-release effects, or reduce side effects.

[0035] Preferably, among the pharmaceutically acceptable equivalents of the compounds provided by the present invention, the fusion peptide refers to a derivative of the compound of the present invention, that is, a polypeptide fragment for the purpose of enhancing the ability to penetrate cell membranes is fused to the nitrogen or carbon end of the compound of the present invention. This polypeptide fragment itself does not have a pharmacological effect but can only improve the ability of the compound to penetrate cell membranes, blood-brain barriers and other tissue barriers.

[0036] In a second aspect, the present invention also protects the use of the peptides and their derivatives described above in the preparation of drugs for decoupling the coupling between gamma-aminobutyric acid transporter 1 (GAT-1) and Syntaxin-1A (a synaptic vesicle SNARE family protein).

[0037] Specifically, the present invention protects the use of ZLQ-1, ZLQ-3, ZLQ-4, ZLQ-5, ZLQ-6, ZLQ-7, ZLQ-8, ZLQ-10, ZLQ-11, ZLQ-12, ZLQ-13, ZLQ-14, ZLQ-15, ZLQ-16, ZLQ-17 and ZLQ-18 in the preparation of a drug for decoupling gamma-aminobutyric acid transporter 1 (GAT-1) and Syntaxin-1A (a synaptic vesicle SNARE family protein).

[0038] In a third aspect, the present invention also protects the use of the peptides and their derivatives described above in the preparation of drugs for treating stroke, brain and spinal cord trauma, anxiety disorders, Alzheimer's disease, depression, central nervous system trauma, epilepsy, Parkinson's disease, Huntington's disease, or affective disorders.

[0039] Beneficial Effects: The peptides and their derivatives of the present invention can uncouple the Syntaxin 1A-GAT-1 coupling, thereby restoring GAT-1's GABA reuptake function and vesicle-mediated release of inhibitory neurotransmitters and BDNF. These substances have the potential to promote neurological recovery after stroke or trauma, as well as rapidly provide anxiolytic and antidepressant effects. They can be used to prepare drugs for the treatment of stroke, traumatic brain injury, anxiety disorders, and depression. Furthermore, due to their unique mechanism of action, these drugs can also be used to prepare drugs for the treatment of Alzheimer's disease and various neurodegenerative diseases.

[0040] It is particularly important to emphasize that the class of peptides and their derivatives described in this patent can remove GAT-1 from Syntaxin 1A, promote the coupling of Syntaxin 1A with other SNARE complex proteins, thereby restoring the GABA reuptake function of GAT-1, reducing the GABA tonic inhibitory current while increasing the GABA phasic inhibitory current, so it will not be like blocking extrasynaptic GABA alone. A Drugs that reduce GABA tonic inhibitory currents do not carry the same risk of epilepsy as drugs that excite GABA in single synapses. A The compounds of the present invention do not cause various side effects like drugs that increase GABA phasic inhibitory currents, and they can also increase vesicle-mediated BDNF release, which has significant advantages in treating stroke, anxiety disorders, major depression, AD and various neurodegenerative diseases.

[0041] The present invention provides a method for treating stroke, anxiety disorders, and major depression by administering a therapeutically effective amount of a class of peptides and their derivatives to mammals (including humans) in need. Specific diseases and conditions that can be treated include stroke, brain trauma, anxiety disorders, major depression, AD, and many more.

[0042] This class of peptides and their derivatives can specifically decouple Syntaxin 1A from the GAT-1 protein, promoting post-stroke damage repair and treating anxiety and depression. Therefore, they can be used in pharmaceuticals that decouple Syntaxin 1A from the GAT-1 protein. In fact, the peptides and their derivatives provided by the present invention are also used to treat other neuropsychiatric diseases related to the interaction between Syntaxin 1A and GAT-1 proteins, such as central nervous system trauma, epilepsy, neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, and Huntington's disease, as well as stroke and affective disorders. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1: ZLQ-0 has a Syntaxin 1A-GAT-1 uncoupling effect. *** p<0.001.

[0044] Figure 2: Screening of ZLQ peptides for their Syntaxin 1A-GAT-1 uncoupling effects. Mature primary neurons were cultured and administered 1 μM of the ZLQ peptides. SS-31, ZLQ-1, ZLQ-3, ZLQ-4, ZLQ-5, ZLQ-6, ZLQ-7, ZLQ-8, ZLQ-10, ZLQ-11, ZLQ-12, ZLQ-13, ZLQ-14, ZLQ-15, ZLQ-16, ZLQ-17, and ZLQ-18 all exhibited Syntaxin 1A-GAT-1 uncoupling effects. ZLQ-3 exhibited the strongest uncoupling effect.

[0045] Figure 3: ZLQ peptides improve motor function in a mouse model of light-induced stroke. ZLQ peptides (3 mg / kg, ip) administered 5-11 days after stroke significantly improved stroke-induced motor dysfunction, as demonstrated by a reduced rate of stumbles in the grid test. n = 10-11, * p<0.05; *** p<0.001, compared with the solvent group.

[0046] Figure 4: ZLQ-21 intranasal administration improves motor function in a mouse light-induced stroke model. (4A) Experimental design. (4B) ZLQ-21 showed a dose-response relationship in improving left forelimb stumbles in mice. With increasing doses, the rate of left forelimb stumbles decreased. n = 10-11, *** p<0.001, compared with the vehicle group. (4C) ZLQ-21 showed a dose-response relationship in improving the left hind limb stumbles in mice. As the dose increased, the stumble rate of the left hind limb of mice decreased. n=10-11, * p<0.05, compared with the vehicle group. (4D) ZLQ-21 showed a dose-response effect on the improvement of forelimb asymmetry in mice. With increasing dose, the coordination of forelimb movement of mice increased and the asymmetry decreased. n=10-11, *** p<0.001, compared with the vehicle group.

[0047] Figure 5: Intranasal administration of ZLQ-21 significantly improves motor dysfunction in the MCAO rat model. (5A) Intranasal administration of ZLQ-21 (10 mg / kg) significantly reduced the rate of left forelimb stumbles in MCAO rats. (5B) Intranasal administration of ZLQ-21 (10 mg / kg) significantly reduced the asymmetry index of forelimb movement in MCAO rats. (5C) Intranasal administration of ZLQ-21 (10 mg / kg) significantly increased the ratio of left and right forelimb use in rats. n = 10-11, *** p<0.001.

[0048] Figure 6: Evaluation of the rapid anxiolytic effect of the ZLQ series of peptides. After administration of the ZLQ series of peptides (3 mg / kg, ip), the time mice spent in the open arms was measured using the elevated plus maze. ZLQ-0, ZLQ-1, ZLQ-2, ZLQ-3, ZLQ-4, ZLQ-5, ZLQ-6, ZLQ-11, ZLQ-15, ZLQ-16, ZLQ-17, ZLQ-18, ZLQ-20, and ZLQ-21 significantly increased the time mice spent in the open arms, exerting a rapid anxiolytic effect. n = 10-11, * p<0.05; ** p<0.01; *** p<0.001, compared with the solvent group.

[0049] Figure 7: Evaluation of the rapid anxiolytic effect of ZLQ-21 after intranasal administration. Intranasal administration of ZLQ-21 significantly increased the time mice spent in the open arms, and the time mice spent in the open arms increased with increasing doses. n = 10-11, * p<0.05; *** p<0.001, compared with the solvent group.

[0050] Figure 8: Intranasal administration of ZLQ-21 significantly reduces CUMS-induced increase in Syntaxin 1A-GAT-1 coupling in the ventral hippocampus of mice. Protein immunoprecipitation experiments showed that intranasal administration of ZLQ-21 (3 mg / kg) significantly reduced Syntaxin 1A-GAT-1 coupling in the ventral hippocampus of mice. *** p<0.001.

[0051] Figure 9: Intranasal administration of ZLQ-21 has a rapid anxiolytic effect. A mouse anxiety model was established using CUMS. Behavior was measured 6 hours after intranasal administration of ZLQ-21 (3 mg / kg). (9A) Intranasal administration of ZLQ-21 significantly increased the time mice spent in the open arms of the elevated plus maze. (9B) Intranasal administration of ZLQ-21 significantly increased the time mice spent in the light compartment of the light-dark compartment. (9C) Intranasal administration of ZLQ-21 significantly increased the number of trips to the center area of ​​the open field test. (9D) Intranasal administration of ZLQ-21 significantly reduced the latency to eat in mice in the novelty suppression of feeding test. * p<0.05; ** p<0.01; *** p<0.001.

[0052] Figure 10: Evaluation of the rapid antidepressant effect of the ZLQ series of peptides. CUMS mouse depression model was established. After administration of the ZLQ series of peptides (3 mg / kg, ip), the tail suspension immobility time of the mice was measured by the tail suspension test. ZLQ-0, ZLQ-3, ZLQ-4, ZLQ-5, ZLQ-6, ZLQ-11, ZLQ-15, ZLQ-16, ZLQ-17, ZLQ-18, ZLQ-20 and ZLQ-21 significantly reduced the tail suspension immobility time of mice and exerted a rapid antidepressant effect. n = 10-11, * p<0.05; ** p<0.01; *** p<0.001, compared with the solvent group.

[0053] Figure 11: Evaluation of the rapid antidepressant effect of ZLQ-21 after intranasal administration. ZLQ-21 intranasal administration significantly reduced the tail suspension immobility time of mice, and with increasing doses, the tail suspension immobility time of mice decreased. n = 10-11, ** p<0.01; *** p<0.001, compared with the solvent group.

[0054] Figure 12: Evaluation of the cognitive impairment-improving effects of the ZLQ series of peptides. A mouse model of Alzheimer's disease was established by intracerebroventricular injection of Aβ. Following administration of the ZLQ series of peptides (3 mg / kg, ip), the mice's ability to discriminate between new and old objects was assessed using a novel object recognition test. ZLQ-0, ZLQ-1, ZLQ-2, ZLQ-3, ZLQ-4, ZLQ-5, ZLQ-6, ZLQ-7, ZLQ-8, ZLQ-10, ZLQ-11, ZLQ-12, ZLQ-13, ZLQ-14, ZLQ-15, ZLQ-16, ZLQ-17, ZLQ-18, ZLQ-20, and ZLQ-21 significantly increased the mice's ability to discriminate between new and old objects, demonstrating an improvement in cognitive impairment. n = 10-11, *p < 0.05; **p < 0.01; ***p < 0.001, compared to the vehicle group.

[0055] Figure 13: Evaluation of the cognitive impairment-improving effects of intranasal ZLQ-21. Intranasal ZLQ-21 significantly increased the ability of mice with Alzheimer's disease to discriminate between old and new objects. This ability increased with increasing doses. n = 10-11, ***p < 0.001, compared to the vehicle group.

[0056] Figure 14-Figure 35: The preferred compounds are ZLQ-0 (Figure 14), ZLQ-1 (Figure 15), ZLQ-2 (Figure 16), ZLQ-3 (Figure 17), ZLQ-4 (Figure 18), ZLQ-5 (Figure 19), ZLQ-6 (Figure 20), ZLQ-7 (Figure 21), ZLQ-8 (Figure 22), ZLQ-9 (Figure 23), ZLQ-10 (Figure 24), Mass spectrometry data of ZLQ-11 (Figure 25), ZLQ-12 (Figure 26), ZLQ-13 (Figure 27), ZLQ-14 (Figure 28), ZLQ-15 (Figure 29), ZLQ-16 (Figure 30), ZLQ-17 (Figure 31), ZLQ-18 (Figure 32), ZLQ-19 (Figure 33), ZLQ-20 (Figure 34) and ZLQ-21 (Figure 35). DETAILED DESCRIPTION

[0057] The specific embodiments of the present invention are further described below. Reagents or instruments used without indicating the manufacturer are considered to be conventional products that can be purchased on the market. The following examples can help those skilled in the art to fully understand the present invention, but are not intended to limit the present invention in any way.

[0058] The compounds involved in the examples are shown in Table 1.

[0059] The general structural formula of the compounds involved in the examples in Table 1 is:

[0060] R-(aa) 4～7 -NH2

[0061] Wherein, aa is a natural or non-natural amino acid, and its configuration can be D- or L-configuration, the polypeptide sequence contains at least 2 to 3 basic natural or non-natural amino acids, and R is H or a monosaccharide or a PEG chain of different lengths or an acetyl group.

[0062] Table 1 Preferred peptides and their derivatives

[0063] Synthesis of the compounds mentioned in the examples;

[0064] The target compound was synthesized by solid phase synthesis method, and the specific method is as follows:

[0065] The peptide was synthesized using Rink amide resin and a standard Fmoc synthesis strategy using a peptide synthesizer. Amino acid side chains were protected with orthogonal Boc, Pbf, or tert-butyl groups. After synthesis, the peptide was deprotected with trifluoroacetic acid and cleaved from the resin. After precipitation with glacial ether, the peptide was filtered and purified using preparative liquid chromatography. The trifluoroacetic acid was then replaced with hydrochloric acid to form the hydrochloride. Finally, mass spectrometry confirmed that the molecular weight was consistent with that of the target peptide.

[0066] Example 1 ZLQ-0:Thr-Lys-Lys-Ala-Val-Lys, MS (ESI + ):calcd for C 30 H 60 N9O8674.46[M+H] + ,found 674.74.

[0067] The structural formula is as follows:

[0068] Example 2 ZLQ-1: D -Arg-Dmt-Cha-Lys- D -Arg-NH2,MS(ESI + ):calcd for C 38 H 68 N 13 O6802.54[M+H] + ,found 803.06.

[0069] The structural formula is as follows:

[0070] Example 3 ZLQ-2: D -Arg-Dmt- D -Lys-Phe-NH2,MS(ESI + ):calcd for C 32 H 50 N9O5640.39[M+H] + ,found 640.74.

[0071] The structural formula is as follows:

[0072] Example 4 ZLQ-3: D -Arg-Dmt-Cha- D -Lys- D -Arg-NH2,MS(ESI + ):calcd for C 38 H 68 N 13 O6802.54[M+H] + ,found 803.35.

[0073] The structural formula is as follows:

[0074] Example 5 ZLQ-4: D -Arg- D-Arg-Dmt-Cha-Lys-NH2,MS(ESI + ):calcd for C 38 H 68 N 13 O6802.54[M+H] + ,found 802.56.

[0075] The structural formula is as follows:

[0076] Example 6 ZLQ-5: D -Arg- D -Arg-Cha-Dmt-Lys-NH2,MS(ESI + ):calcd for C 38 H 68 N 13 O6802.54[M+H] + ,found 803.18.

[0077] The structural formula is as follows:

[0078] Example 7 ZLQ-6: D -Arg- D -Arg-Ala-Val- D -Arg-NH2,MS(ESI + ):calcd for C 26 H 54 N 15 O5656.44[M+H] + ,found 656.69.

[0079] The structural formula is as follows:

[0080] Example 8 ZLQ-7: D -Arg- D -Arg-Ala-Val- D -Lys-NH2,MS(ESI + ):calcd for C 26 H 54 N 13 O5628.44[M+H] + ,found 628.72.

[0081] The structural formula is as follows:

[0082] Example 9 ZLQ-8: D-Arg- D -Arg-Ala-Val-Lys-NH2,MS(ESI + ):calcd for C 26 H 54 N 13 O5628.44[M+H] + ,found 628.84

[0083] The structural formula is as follows:

[0084] Example 10 ZLQ-9: Arg-Arg- D -Ala- D -Val-Arg-NH2,MS(ESI + ):calcd forC 26 H 54 N 15 O5656.44[M+H] + ,found:656.88.

[0085] The structural formula is as follows:

[0086] Example 11 ZLQ-10: Arg-Arg-Ala-Val-Arg-NH2, MS (ESI + ):calcd forC 26 H 54 N 15 O5656.44[M+H] + ,found 656.75.

[0087] The structural formula is as follows:

[0088] Example 12 ZLQ-11: D -Arg-Dmt-Cha- D -Lys-NH2,MS(ESI + ):calcd for C 32 H 56 N9O5646.44[M+H] + ,found 646.37.

[0089] The structural formula is as follows:

[0090] Example 13 ZLQ-12: D -Arg-Dmt-Cha- D -Arg-NH2,MS(ESI+ ):calcd for C 32 H 56 N 11 O5674.45[M+H] + ,found 674.45.

[0091] The structural formula is as follows:

[0092] Example 14 ZLQ-13: D -Arg-Dmt-Cha-Lys-NH2,MS(ESI + ):calcd for C 32 H 56 N9O5646.44[M+H] + ,found 646..46.

[0093] The structural formula is as follows:

[0094] Example 15 ZLQ-14: D -Arg-Dmt-Phe- D -Lys- D -Arg-NH2,MS(ESI + ):calcd for C 38 H 62 N 13 O6796.49[M+H] + ,found 796.66.

[0095] The structural formula is as follows:

[0096] Example 16 ZLQ-15: D -Arg-Tyr-Cha-Lys-NH2,MS(ESI + ):calcd for C 30 H 52 N9O5618.41[M+H] + ,found 618.37.

[0097] The structural formula is as follows:

[0098] Example 17 ZLQ-16: D -Arg-Phe-Cha-Lys-NH2MS(ESI + ):calcd for C 30 H 52N9O4602.41[M+H] + ,found 602.34.

[0099] The structural formula is as follows:

[0100] Example 18 ZLQ-17: Arg-Dmt-Cha-Lys-NH2, MS (ESI + ):calcd for C 32 H 56 N9O5646.44[M+H] + ,found 646.49.

[0101] The structural formula is as follows:

[0102] Example 19 ZLQ-18: Arg-Dmt- D -Cha-Lys-NH2MS(ESI + ):calcd for C 32 H 56 N9O5646.44[M+H] + ,found 646.36.

[0103] The structural formula is as follows:

[0104] Example 20 ZLQ-19: D -Arg-Dmt-Phe-Lys-NH2,MS(ESI + ):calcd for C 32 H 50 N9O5640.39[M+H] + ,found 640.41.

[0105] The structural formula is as follows:

[0106] Example 21 ZLQ-20:mPEG1000- D -Arg-Dmt-Cha- D -Lys- D -Arg-NH2

[0107] The structural formula is as follows:

[0108] Example 22 ZLQ-21: Glucose- D -Arg-Dmt-Cha- D -Lys- D-Arg-NH2 964,MS(ESI + ):calcd for C 44 H 78 N 13 O 11 964.59[M+H] + ,found:964.81.

[0109] The structural formula is as follows:

[0110] Example 23 ZLQ-22: Ac- D -Arg-Dmt-Cha- D -Lys- D -Arg-NH2,MS(ESI + ):calcd for C 40 H 70 N 13 O7,844.55,[M+H] + ,found:844.61

[0111] The structural formula is as follows:

[0112] Effects of the target compounds mentioned in the examples on the interaction between Syntaxin 1A and GAT-1

[0113] Example 24 Primary Neuron Culture

[0114] Take a newborn mouse within 24 hours of birth and disinfect it with a chlorhexidine solution and then 75% ethanol, then disinfect the head skin with iodine. Hold the neck skin with your left hand to stabilize the head. Use ophthalmic forceps in your right hand to cut open the skull, exposing both cerebral hemispheres. Remove the two cerebral cortices and place them in a culture dish filled with D-Hank's solution; remove the membrane. Place the removed cerebral cortex in a 5mL beaker and use ophthalmic scissors to cut the cortex into pieces less than 1mm. 3Take out the incubated 0.125% Trypsin Solution, add 20 mL to the conical flask, mix well; digest in the incubator (37 ° C) for 10 minutes. After digestion, use a pipette to gently blow until there are no tissue pieces in the suspension. Transfer the cell suspension to a 200-mesh sieve and filter. Use DMEM / F12 (1:1) medium containing 10% FBS to stop the enzyme reaction. Centrifuge the filtrate at 2500 rpm × 3 min, remove the supernatant, and use a glass pipette with a smooth tip to gently blow and disperse the cells. Centrifuge, use Neurobasal medium containing 2% B27, 0.5 mM L-glutamine, 5 IU penicillin and 5 μg / mL streptomycin to inoculate in a culture dish coated with PORN (10 μg / mL), and the inoculation density is 1 × 10 5 cells / cm 2 The cells were cultured in an atmosphere of 5% CO2 at 37°C, with half the volume of Neurobasal medium replaced every 3-4 days during the culture process.

[0115] Example 25 Co-immunoprecipitation of Syntaxin 1A and GAT-1

[0116] Aspirate the culture medium from the dish, wash three times with PBS, and add an appropriate amount of 100 mM HEPES (containing 200 mM sodium chloride, 10% glycerol, 2 mM sodium pyrophosphate, 2 mM dithiothreitol, 1 mM EDTA, 1 mM benzamidine, 0.1 mM sodium vanadate, 1 μM pepstatin, 10 μg / mL aprotinin, 10 μg / mL leupeptin, and 10 μM phenylmethylsulfonyl fluoride). Scrape the cells with a cell scraper, lyse on ice for 30 minutes, and centrifuge at 12,000 × g for 15 minutes at 4°C. Carefully aspirate the supernatant to obtain the protein extract. Remove 50 μL of Protein G-Sepharose beads, wash twice with PBS, and resuspend the beads in 50 μL of PBS. Add Syntaxin 1A antibody and shake at 4°C for 3-4 hours. Add the extracted protein supernatant (primary neuronal protein or cortical tissue protein) to the beads to a final concentration of 1:100 for Syntaxin 1A antibody. Shake overnight at 4°C. The next day, wash the protein-antibody-beads complex with PBS three times, shaking at 4°C for 20 minutes each time. Discard as much supernatant as possible during the final wash and resuspend the protein-antibody-beads complex in 50 μL of PBS.

[0117] Add 0.2 volumes of 6× protein loading buffer (300 mmol / L Tris (pH 6.8), 600 mM DTT, 12% SDS, 0.6% bromophenol blue, 60% glycerol) to the protein sample to be tested, boil at 100°C for 5 minutes, centrifuge at 12,000 rpm for 10 minutes, and store the supernatant at -80°C until analysis. Cast a 10% SDS-PAGE gel and separate the protein sample by electrophoresis at a constant voltage of 100 V. After electrophoresis, remove the gel and soak it in transfer buffer (39 mmol / L glycine, 48 mmol / L Tris base, 0.037% SDS, 20% methanol) for 10 minutes. Then, measure a nitrocellulose membrane (NC membrane) slightly larger than the gel (1 cm in length and width) and soak it in transfer buffer for 10 minutes. Sandwich the membrane and gel between three layers of filter paper, top and bottom, to create a sandwich. Press firmly in place and place in an electrophoretic transfer tank. Transfer at 300 mA for 2.5 hours. After transfer, visualize protein bands using Ponceau Red S (2 g; trichloroacetic acid 30 g; sulfosalicylic acid 30 g; dilute to 100 mL) to confirm transfer efficiency. Rinse the NC membrane several times with deionized water after protein bands appear. Block with 5% skim milk powder for 1 hour, wash the membrane three times with TBST for 10 minutes, and incubate with the primary antibody overnight. The next day, the primary antibody was discarded and the membrane was washed with TBST for 10 minutes three times. Incubation was then performed with horseradish peroxidase-conjugated goat anti-rabbit secondary antibody for 2 hours. The membrane was then washed with TBST for 10 minutes three times. After the final wash, the membrane was quickly mixed with 1 mL each of ECL luminescent solution A and solution B (Super Signal West Pico Trial Kit, Pierce) and allowed to react on the membrane for approximately 5 minutes. The membrane was then wrapped in plastic wrap and fixed in an X-ray cassette. The film was quickly covered in a darkroom, the cassette closed, and exposed to light for a moderate amount of time. The film was removed and immediately immersed in developer solution for 1-2 minutes. The film was then placed in fixer solution until the film was completely fixed, rinsed with water, and air-dried. The film was scanned using a gel imaging system (Bio-RAD), and data analysis was performed using Quantity One (Bio-RAD) software.

[0118] Evaluation of the effect of the target compound involved in the embodiment on promoting functional recovery after stroke

[0119] Example 26 Preparation of Light-Induced Cerebral Ischemia Model

[0120] A focal cerebral ischemia model was created by irradiating Rose Bengal with light to generate oxygen free radicals, which damage vascular endothelial cells. Adult mice were anesthetized with 2% isoflurane gas and fixed in a stereotaxic apparatus. A midline scalp incision was made to expose the skull, and connective tissue was removed and air-dried. A cold light source with a 2 mm diameter circular spot was placed vertically above the skull, with the center offset 1.5 mm to the right of bregma. Five minutes after intraperitoneal injection of Rose Bengal (100 mg / kg), the cold light source was adjusted to 12,000 lux and irradiated for 15 minutes. Following irradiation, the cold light source was removed, and the wound was sutured and disinfected. Throughout the surgery, the animal's body temperature was maintained at 37 ± 0.5°C using a temperature-controlled infrared lamp. In the sham-operated group, the scalp was incised and injected with Rose Bengal, but no cold light exposure was performed. After surgery, the animals were returned to their respective home cages and carefully monitored until they regained consciousness.

[0121] Example 27 Preparation of a cerebral ischemia model induced by middle cerebral artery occlusion

[0122] A focal cerebral ischemia model was established by middle cerebral artery occlusion (MCAO). Briefly, Sprague-Dawley rats were anesthetized with 5% isoflurane gas. A single nylon filament, which had been flamed and smoothed, was inserted into the internal carotid artery via the left external carotid artery stump. The filament was gently advanced 20–21 mm past the skull base bifurcation of the internal carotid artery until slight resistance was felt. Throughout the procedure, the animal's body temperature was maintained at 37 ± 0.5°C using a temperature-controlled infrared lamp. After 90 minutes of ischemia, the filament was withdrawn to allow reperfusion of the ischemic area. The animals were then returned to their respective home cages and carefully monitored until awake. Sham surgery was performed identically, but without occluding the middle cerebral artery.

[0123] Example 28 Grid Experiment

[0124] The specific dimensions of the grid apparatus for mice and rats were: length × width × height: 32 × 20 × 50 cm, with a grid size of 1.2 × 1.2 cm; length × width × height: 60 × 60 × 60 cm, with a grid size of 3 × 3 cm. A camera placed below the grid recorded the entire walking process. The animals were allowed to walk freely on the grid for 5 minutes, and the number of stumbles per foot and the total number of steps were counted. The percentage of stumbles per foot was calculated as follows: [number of stumbles / (number of stumbles + number of non-stumbles) × 100]. A stumble was considered if the animal's limbs crossed the grid without support or if the wrist simply rested on the edge of the grid.

[0125] Example 29 Barrel Experiment

[0126] Taking advantage of animals' tendency to explore by scraping against walls, researchers have designed a method to assess the motor coordination of the animals' right and left limbs by placing them in custom-made cylinders and recording the time each animal's forelimbs spent scraping against the wall. Mice were placed in uncovered, transparent glass cylinders 10 cm in diameter and 15 cm high, while rats were placed in a 20 cm diameter, 30 cm high cylinder. In addition to the aforementioned glass cylinder, the experimental setup also required a mirror placed behind the cylinder to ensure that a high-definition camera could clearly capture the animal's back facing the camera. While exploring the cylinder, the animals would simultaneously stand on the cylinder wall using either both forelimbs or one limb. Each animal was allowed to freely explore the cylinder for 5 minutes. After all animals were recorded, the videos were analyzed by a third-party, blinded researcher in a randomized, double-blind manner. The videos were played at 0.2x speed, and the total scraping time of the animal's left and right forelimbs, as well as the time spent scraping against the wall with each forelimb, was recorded. The asymmetry index was calculated as follows: [(the time of peeling off the wall on the affected side - the time of peeling off the wall on the healthy side) / the total peeling off the wall time] × 100%.

[0127] Example 30 Adhesion Removal Experiment

[0128] Wrap a 3 cm long, 1 cm wide piece of tape around the rat's forepaw, allowing the fingers to slightly protrude from the formed sleeve. Place the rat in the testing cage and begin recording time. When observing the rat in the testing cage, it may be observed that the rat will use its mouth to chew on the tape on its forelimb in an attempt to remove it. Two timers are used during recording: the first timer runs continuously for 30 seconds, and the second timer counts as the animal attempts to remove the tape. Each rat is recorded five times. After each recording, the tape is removed from its forelimb and the rat is returned to its cage to rest for 3 minutes. Finally, the interest score is calculated by dividing the time the rat chews the tape in 30 seconds by 30 seconds. The two highest ratios from the five recordings are averaged to form the final score for assessing sensorimotor ability. The modified tape removal ratio is calculated as follows: (interest ratio on the affected side / interest ratio on the unaffected side) × 100%.

[0129] Evaluation of the anxiolytic effects of the target compounds involved in the examples

[0130] Example 31 Chronic Unpredictable Mild Stress Anxiety Model

[0131] Mice were subjected to chronic, unpredictable mild stress to establish an anxiety model. The stressful conditions lasted 14 days and included: food restriction (reduced food supply or food deprivation for 24 hours); tilted cage (cages tilted against a wall for 24 hours, restricting the mice's range of movement and making it difficult to access food and water); empty cage (bedding deprivation for 24 hours); wet cage (bedding deprivation with a layer of cold water added, allowing the mice to soak in cold water for 8 hours); ice walking (cages covered with ice, allowing the mice to walk on ice for 2 hours); circadian reversal (lighting rhythm altered, reversing circadian rhythm); bottle restriction (placing the mice in a small glass box, depriving them of their range of movement); and electric shock (foot shocks delivered at random times and frequencies within 180 seconds).

[0132] Example 32 Novel food intake suppression experiment

[0133] The novelty food suppression test is an animal behavior test used to detect conflict psychology. The motivation to eat and the fear of entering a new environment in the bright central area form a conflict. The feeding latency of mice is used to evaluate the anxiety-like behavior of mice. The mice are placed in a single cage with cleaned food residues and new bedding, and the mice are weighed and fasted for 24 hours. Prepare a plastic box (50×50×20cm 3 ), an opaque disc (6 cm in diameter) was placed in the center and covered with a thin layer of bedding. Regular feed of uniform size was placed in the disc to facilitate access by mice, and a desk lamp was hung above the center of the disc to provide lighting. After turning off the lights in the room, the mice were placed in the lower left corner of the plastic box and the timing was started. The experimenter observed the mice quietly, and mice that showed obvious weakness or a significant decrease in activity were excluded from the study. When the mice began to gnaw on the food (defined as the mice grabbing the food with their front paws and eating it into their mouths), the timing was stopped to obtain the feeding latency. If the mouse grabs the food to the periphery of the disc to eat, the nearby bedding was replaced to prevent the next mouse from eating food scraps. After recording the feeding latency of each mouse (the feeding latency was recorded as 6 minutes if it exceeded 6 minutes), the mice were returned to their home cages and fed a single pellet of 3-5g of feed weighed in advance. After the experimenter leaves the room and the mice eat freely under the feeding light for 40 minutes, the weight difference of a single feed pellet before and after eating is calculated to obtain the food intake, and the difference is divided by the weight of the mice to obtain the standard food intake. There should be no statistical difference in the standard food intake, indicating that the hunger level is similar.

[0134] Example 33 Elevated plus maze test

[0135] The elevated plus maze test is a classic experimental method for evaluating anxiety behavior in rodents. The elevated plus maze consists of a central platform (5×5 cm 2 ), 50 cm from the ground, connect two "safety" arms (closed arms) (30×5 cm 2), with side walls of 15 cm in height, and two "risk" arms (open arms) lacking side walls (30 × 5 cm 2 ) composition. The mouse is placed steadily at the starting section of the open arm, the blackout curtain is pulled up and the gap in the curtain is clamped with a clip to ensure that no light leaks. The mouse can move freely in a quiet and private environment completely surrounded by the curtain. When the mouse enters the central area, start recording a video of free activity for 5 minutes, then wipe the maze with 75% alcohol to remove odors and excrement, and then place the next mouse for re-testing. After all the mice have been tested, the Top Scan LITE system (Clever Sys Inc.) is used to analyze and record the time the mouse stays in the open and closed arms of the maze (staying is defined as the mouse's limbs occupying more than 80% of the arm).

[0136] Example 34 Open field test

[0137] The open field test is a method to evaluate the autonomous movement, exploration ability and stress level of experimental animals in unfamiliar environments. 3 A 15 x 15 cm square area in the center of a plastic box was defined as a central area that was perceived as aversive and potentially dangerous to mice. Animals exhibiting anxiety-like behaviors tended to explore the peripheral areas more frequently. A mouse was placed in one corner of the box, and a video of the mouse's free movement was recorded for 5 minutes. The area was cleaned with 75% alcohol before the next mouse was placed. The Top Scan LITE system (Clever Sys Inc.) was used to analyze the number of times the mouse crossed the central area to assess anxiety-like behavior.

[0138] Example 35 Light and dark box experiment

[0139] To evaluate the anxiety behavior of mice, we also used the light-dark box test, which is a chamber divided into two light compartments (20 × 30 × 40 cm). 3 ) and dark compartment (20×30×40cm 3 ) boxes, which were interconnected. Mice exhibiting anxiety-like behavior spent less time in the bright compartment. At the beginning of the test, mice were gently placed in the dark compartment and a video was recorded of them moving freely between the two compartments for 5 minutes. Before placing a new mouse, the box was cleaned with 75% ethanol to eliminate any residual odor and excrement. The Top Scan LITE system (Clever Sys Inc.) was used to analyze and record the time each mouse spent in the two compartments to assess anxiety behavior.

[0140] Evaluation of the antidepressant effects of the target compounds involved in the examples

[0141] Example 36 Chronic Unpredictable Mild Stress Depression Model

[0142] Mice were subjected to chronic, unpredictable mild stress to establish a mouse depression model. The stressors lasted 28 days and included: food restriction (reduced food supply or food deprivation for 24 hours); tilted cage (cages tilted against a wall for 24 hours, restricting the mice's range of movement and making it difficult to access food and water); empty cage (bedding deprivation for 24 hours); wet cage (bedding deprivation with a layer of cold water added, allowing the mice to soak in cold water for 8 hours); ice walking (cages covered with ice, allowing the mice to walk on ice for 2 hours); circadian reversal (lighting rhythm altered, reversing circadian rhythm); bottle restriction (placing the mice in a small glass box, depriving them of their range of movement); and electric shock (foot shocks administered at random times and frequencies within 180 seconds).

[0143] Example 37 Tail suspension test

[0144] After allowing the mice to adapt to the experimental lights in the tail suspension test room for 30 minutes, they were wrapped with medical tape of about 20 cm at both ends about 1 cm away from the end of the tail and hung upside down in the tail suspension test box. The test process was recorded for 6 minutes. After the end of the experiment, the immobility time of the last 5 minutes was analyzed using TopScan LITE software (Clever Sys) to reflect the behavioral despair of the mice.

[0145] Evaluation of the anti-cognitive dysfunction effects of the target compounds involved in the examples

[0146] Example 38 Preparation of Cognitive Impairment Mouse Model

[0147] Aβ1-42 was first prepared by dissolving it in 1,1,1,1,3,3,3-hexafluoro-2-propanol, flash-freezing it in liquid nitrogen, and then lyophilizing it to completely remove the solvent. The lyophilized Aβ1-42 was then dissolved in 100 mM sodium hydroxide and stored at -80°C until use. Freshly prepared Aβ1-42 (0.3 nmol / 2 μL) was injected into the bilateral lateral ventricles of mice (A: -0.3 mm, L: ±1.0 mm, D: -2.5 mm) via microsyringe.

[0148] Example 39 New Object Recognition Experiment

[0149] The novel object recognition test assesses cognitive memory abilities by leveraging the innate tendency of experimental animals to explore novel objects. The novel object recognition test consists of three phases: habituation, learning, and testing. During the habituation phase, mice are placed in an open field (30 cm × 30 cm × 37 cm) and allowed to freely explore the area for 10 minutes. During the learning phase, two identical objects (ensuring they are odorless and cannot be moved) are placed in the open field, approximately 7 cm from either wall. The mice are then placed in the open field, videotaped for 10 minutes while they freely move, and the time they spend exploring each object is recorded. During the testing phase, one of the objects is replaced with a novel object, and the time spent exploring each object is recorded over the same 10-minute observation period. The apparatus is thoroughly cleaned with 75% ethanol before the next mouse is placed. Object exploration is defined as the rodent's nose sniffing the object at a distance of less than or equal to 2 cm (simply climbing or leaning on the object is not considered exploratory behavior). Learning and memory abilities are assessed based on the length of time the animals spend exploring the familiar and novel objects.

[0150] The protection content of the present invention is not limited to the above embodiments. Without departing from the spirit and scope of the inventive concept, changes and advantages that can be thought of by those skilled in the art are included in the present invention and are protected by the appended claims.

Claims

1. A peptide and its derivatives and pharmaceutically acceptable salts, hydrates, solvent mixtures, metabolites or prodrugs thereof, characterized in that: The peptide and its derivatives conform to the general structural formula of Formula 1: R-(aa) 4～7 -NH2 Formula 1 Wherein, aa is a natural or non-natural amino acid, and its configuration is D or L-configuration. The peptide is formed by condensing 4 to 7 amino acids through amide bonds, and the sequence contains at least 2 to 3 basic natural or non-natural amino acids. R is hydrogen or a sugar group or a PEG chain of different lengths or an acetyl group.

2. The peptide and its derivatives and pharmaceutically acceptable salts, hydrates, solvent mixtures, metabolites or prodrugs according to claim 1, characterized in that: The natural amino acids are selected from glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, and histidine, wherein any one or more of alanine, valine, leucine, isoleucine, methionine, tryptophan, tyrosine, phenylalanine, lysine, or arginine are preferred.

3. The peptide and its derivatives and pharmaceutically acceptable salts, hydrates, solvent mixtures, metabolites or prodrugs according to claim 1, characterized in that: The non-natural amino acid is selected from one or more of phenylalanine, tyrosine, tryptophan, 1-naphthylalanine, 2-naphthylalanine, 3-aminopropionic acid, 4-aminobutyric acid, 5-aminovaleric acid, or 6-aminohexanoic acid substituted with alkyl or halogen on the aromatic ring; or selected from one or more of ornithine, 2-pyridylalanine, 3-pyridylalanine, 4-pyridylalanine, 2,4-diaminobutyric acid, N-methyllysine, selenocysteine, or pyrrolysine; Preferably, the non-natural amino acid is selected from one or more of 2,6-dimethyltyrosine, 3,5-dimethyltyrosine, 2-ethyl-6-methyltyrosine, 2,3,5,6-tetramethyltyrosine, 2-isopropyl-6-methyltyrosine, 2,3,5-trimethyltyrosine, 2,3,6-trimethyltyrosine, 2,6-dimethylphenylalanine, 2,4,6-trimethylphenylalanine, cyclohexylalanine, cyclohexylglycine, 1-naphthylalanine, 2-naphthylalanine, ornithine, or 4-pyridylalanine.

4. A peptide and its derivatives and pharmaceutically acceptable salts, hydrates, solvent mixtures, metabolites or prodrugs according to any one of claims 1 to 2, characterized in that: When the R group is PEG, its molecular weight is 200-2000, preferably 1000.

5. A peptide and its derivatives and pharmaceutically acceptable salts, hydrates, solvent mixtures, metabolites or prodrugs according to any one of claims 1 to 2, characterized in that: When the R group is a glycosyl group, the glycosyl group is selected from a monosaccharide, a polysaccharide, or a derivatized monosaccharide or polysaccharide; Preferably, the R group is selected from glucose, mannose, galactose, allose, altrose, gulose, idose, talose, ribose, xylose, arabinose, or lyxose; More preferably, the R group is selected from one or more of glucose, galactose, ribose, arabinose, and modified derivative sugars and polysaccharides of the above sugars.

6. A class of peptides and their derivatives and pharmaceutically acceptable salts, hydrates, solvent mixtures, metabolites or prodrugs, as shown below:

7. A class of peptides and their derivatives and pharmaceutically acceptable salts, hydrates, solvent mixtures, metabolites or prodrugs, as shown below:

8. The peptide and its derivatives and pharmaceutically acceptable salts, hydrates, solvent mixtures, metabolites or prodrugs according to claim 7 or 8, characterized in that: The peptide and its derivatives are ZLQ-0, ZLQ-1, ZLQ-2, ZLQ-3, ZLQ-4, ZLQ-5, ZLQ-6, ZLQ-7, ZLQ-8, ZLQ-10, ZLQ-11, ZLQ-12, ZLQ-13, ZLQ-14, ZLQ-15, ZLQ-16, ZLQ-17, ZLQ-18, ZLQ-20 or ZLQ-21.

9. Use of a peptide according to any one of claims 1 to 8 and its derivatives and pharmaceutically acceptable salts, hydrates, solvent mixtures, metabolites or prodrugs thereof in the preparation of a drug for decoupling γ-aminobutyric acid transporter 1 and Syntaxin-1A.

10. Use of a peptide according to any one of claims 1 to 8 and its derivatives and pharmaceutically acceptable salts, hydrates, solvent mixtures, metabolites or prodrugs thereof in the preparation of drugs for treating stroke, brain and spinal cord trauma, anxiety disorders, Alzheimer's disease, depression, central nervous system trauma, epilepsy, Parkinson's disease, Huntington's disease, or affective disorders.

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