Computational biology in topical bioactive peptide discovery for cosmeceutical application:a concise review

Regenerative medicine and anti-aging research have made great strides at the molecular and cellular levels in dermatology and the medical aesthetic field,targeting potential treatments with skin therapeutic and intervention pathways,which make it possible to develop effective skin regeneration and repair ingredients.With the rapid development of computational biology,bioinformatics as well as artificial intelligence(A.I.),the development of new ingredients for regenerative medicine has been greatly accelerated,and the success rate has been improved.Some application cases have appeared in topical skin regeneration and repair scenarios.This review will briefly introduce the application of bioactive peptides in skin repair and anti-aging as emerging ingredients in cosmeceutics and emphasize how A.I.based computational biology technology may accelerate the development of innovative peptide molecules and ultimately translate them into potential skin regenerative and anti-aging scenarios.Typically,two research routines have been summarized and current limitations as well as directions were discussed for border applications in future research.

Molecular characteristics and structure–activity relationships of food-derived bioactive peptides

Peptides are functional active fragments of proteins which can provide nutrients needed for human growth and development,and they also have unique physiological activity characteristics relative to proteins.Bioactive peptides contain a great deal of development potential.More specifically,food-derived bioactive peptides have the advantages of a wide variety of sources,unique structures,high efficiency and safety,so they have broad development prospects.This review provides an overview of the current advances regarding the preparation,functional characteristics,and structure–activity relationships of food-derived bioactive peptides.Moreover,the prospects for the future development and application of food-derived bioactive peptides are discussed.This review may provide a better understanding of foodderived bioactive peptides,and some constructive inspirations for further research and applications in the food industry.

Polydopamine-modified chitin conduits with sustained release of bioactive peptides enhance peripheral nerve regeneration in rats

The introduction of neurotrophic factors into injured peripheral nerve sites is beneficial to peripheral nerve regeneration.However,neurotrophic facto rs are rapidly degraded in vivo and obstruct axonal regeneration when used at a supraphysiological dose,which limits their clinical benefits.Bioactive mimetic peptides have been developed to be used in place of neurotrophic factors because they have a similar mode of action to the original growth fa ctors and can activate the equivalent receptors but have simplified sequences and structures.In this study,we created polydopamine-modified chitin conduits loaded with brain-derived neurotrophic factor mimetic peptides and vascular endothelial growth fa ctor mimetic peptides(Chi/PDA-Ps).We found that the Chi/PDA-Ps conduits were less cytotoxic in vitro than chitin conduits alone and provided sustained release of functional peptides.In this study,we evaluated the biocompatibility of the Chi/P DA-Ps conduits.Brain-derived neurotrophic factor mimetic peptide and vascular endothelial growth fa ctor mimetic peptide synergistically promoted prolife ration of Schwann cells and secretion of neurotrophic factors by Schwann cells and attachment and migration of endothelial cells in vitro.The Chi/P DA-Ps conduits were used to bridge a 2 mm gap between the nerve stumps in rat models of sciatic nerve injury.We found that the application of Chi/PDA-Ps conduits could improve the motor function of rats and reduce gastrocnemius atrophy.The electrophysiological results and the microstructure of regenerative nerves showed that the nerve conduction function and re myelination was further resto red.These findings suggest that the Chi/PDA-Ps conduits have great potential in peripheral nerve injury repair.

Isolation and identification of novel casein-derived bioactive peptides and potential functions in fermented casein with Lactobacillus helveticus

The present study here establishes a complete and effective method for isolating,purifying and identifying extracellular and intracellular peptides,and also describes the characters and bioactivities of peptides from fermented casein with Lactobacillus helveticus.Intracellular peptides are much larger in quantity and more complex in composition than extracellular peptides,between which the correlation reveals proteolytic and metabolic mechanisms.In addition,totally 241 different peptide sequences were identified by Nano LC–MS/MS from casein(212)and Lactobacillus helveticus proteins(29).These casein-derived peptides mostly originated from-casein,followed byS1-casein,-casein,andS2-casein,and came from extracell(69)and intracell(143),in which common peptides have a total of 27.Forty-four of the identified peptides were previously described as bioactive,including angiotensinconverting enzyme(ACE)-inhibitory,antioxidant,immunomodulating,antimicrobial,DPP-IV inhibitory,antiamnesic and anticancer effects and so on.Thirteen peptides with the potential of some biological activities are obtained,which were described in previous studies.A total of 47 novel peptides of 5 to 26 amino acids that were not disclosed were obtained.The new sources of natural bioactive peptides may have the very high application value as potential new peptide drugs for treatment human diseases.The product peptide DELQDKIHPF found in both extracell and intracell was quantitatively analyzed using the MRM mode of UPLC-U3Q,23.1 and 9.76 ng/mL,respectively.The quantitative analysis of the potential bioactive peptide may also advance the production of peptide products in the future.

Screening of protease-producing marine yeasts for production of the bioactive peptides

Over 400 yeast strains from seawater and sediments were obtained, but only five strains named HN2 -3, N13d, N13C, Mb5 and HN3 - 2 among them could form clear zones around their colonies on the double plates with 2.0% casein. Peptides in the hydrolysate produced by the proteases from strains HN2 -3 and N13d had higher angiotensin I-converting-enzyme （ACE）-inhibitory activity. The two marine yeast strains were identified to be Aureobasidium pullulans according to the results of routine yeast identification and molecular methods. After purification of the proteases from the two marine yeast strains, it was found that the optimal pH for them was both 9.0, both of them were serine alkaline protease. However, the optimal temperature for the protease from the strain HN2 -3 was 52℃ while that from strain N13d was 48℃. ACE-inhibitory activity of the peptides in the hydrolysate of shrimp protein produced by the purified protease from the strain HN2 -3 was the highest while antioxidant activity in the hydrolysate of spirulina protein produced by the purified protease from the strain N13d was the highest.

Effect of Bioactive Peptides(BPs) on the Development of Pacific White Shrimp(Litopenaeus vannamei Boone, 1931)

The present study was conducted to evaluate the feasibility of replacing fish meal(FM) with bioactive peptides(BPs) in diet of white shrimp(Litopenaeus vannamei). The changes in growth performance, body composition, non-specific immunity, and water quality were examined after the shrimp were fed four diets, in which 0%(control), 33.3%, 66.7% and 100% of FM was replaced by BPs, respectively. The groups were designated as Con, 1/3BPs, 2/3BPs, and 3/3BPs. A total of 720 shrimp with an initial body weight of 1.46 ± 0.78 g were fed the experimental diets for 56 days. The results revealed that: 1) the weight gain rate(WGR) in 1/3BPs, 2/3BPs, and 3/3BPs was significantly higher than that in Con(P < 0.05), while no significant difference was found on survival rate and feed conversion ratio(FCR); 2) the whole-body crude protein(CP) and crude lipids(CL) were significantly different among groups, while there was no significant difference between crude ash and phosphorus contents; 3) the levels of acid phosphatase(ACP), lysozyme(LZM), superoxide dismutase(SOD), phenol oxidase(PO) and bactericidal activity increased significantly with the inclusion of BPs; 4) in terms of water quality, no significant difference was found in p H and dissolved oxygen among diets during the whole experimental period. Moreover, even though nitrite and ammonium levels tended to increase with time, there was no significant difference among groups. The results indicated that BPs is an applicable alternative of protein source, which can substitute FM in the diets of L. vannamei; it is able to effectively promote growth performance and improve immunity. Moreover, BPs in the diets had no negative impact on water quality.

The selection of alkaline protease-producing yeasts from marine environments and evaluation of their bioactive peptide production

A total of 400 yeast strains from seawater, sediments, saltern mud, marine fish guts, and marine algae were obtained. The protease activity of the yeast cultures was estimated, after which four strains （HN3.11, Nllb, YF04C and HN4.9） capable of secreting extracellular alkaline protease were isolated. The isolated strains were identified as Aureobasidium pullulans, Yarrowia lipolytica, lssatchenkia orientalis and Cryptococcus cf. aureus. The optimal pH of the protease activity produced by strains HN3.11, YF04C, and HN4.9 was 9.0, while that of the protease produced by strain N1 lb was 10.0. The optimal temperature for protease activity was 45℃for strains HN3.11, N11b, and YF04C, and 50℃ for strain HN4.9. After digestion of shrimp （Penaeus vannamei） protein and spirulina （Arthospira platens＆） protein with the four crude alkaline proteases, the filtrate from spirulina （Arthrospira platensis） powder digested by the crude alkaline protease of strain HNYl 1 was found to have the highest antioxidant activity （61.4%） and the highest angiotensin I converting enzyme （ACE）-inhibitory activities （68.4%）. The other filtrates had much lower antioxidant activity and ACE-inhibitory activities.

A review on mechanisms of action of bioactive peptides against glucose intolerance and insulin resistance

Insulin resistance leads to impaired glucose metabolism by disrupting both insulin secretion and sensitivity.Insulin resistance plays a key role in the pathophysiology of type 2 diabetes and metabolic syndrome.Reviews on the mechanisms of action of bioactive peptides on glucose homeostasis and insulin resistance are scarce.The recent discoveries of pathways and target cells in the management of glucose and energy metabolism have opened up new opportunities for identification of novel bioactive peptides on enhancing adipocyte differentiation and insulin signaling,glucose uptake,cholecystokinin receptor expression and activation,as well as insulin mimetics and incretin stimulants.Examples of food-derived bioactive peptides with glucoregulatory properties include Trp-Glu-Lys-Ala-Phe-Lys-Asp-Glu-Asp(WEKAFKDED),Gln-Ala-MetPro-Phe-Arg-Val-Thr-Glu-Gln-Glu(QAMPFRVTEQE),Glu-Arg-Tyr-Pro-Ile-Leu(ERKPIL),Val-Phe-LysGly-Leu(VFKGL),Phe-Leu-Val(FLV),Val-Pro-Pro(VPP),Ile-Arg-Trp(IRW),Ala-Lys-Ser-Pro-Leu-Phe(AKSPLF),Ala-Thr-Gln-Pro-Leu-Phe(ATNPLF),Phe-Glu-Glu-Leu-Gln(FEELN),Leu-Ser-Val-Ser-Val-Leu(LSVSVL),Val-Arg-Ileu-Arg-Leu-Leu-Gln-Arg-Phe-Asn-Lys-Arg-Ser(VRIRLLQRFNKRS),and Ala-GlyPhe-Ala-Gly-Asp-Asp-Ala-Pro-Arg(AGFAGDDAPR).However,as yet,clinical evidence on the effi cacy of such bioactive peptides is rare but is inevitable to establish their applications against glucose intolerance and insulin resistance.

Study on the Molecular Weight Composition and Antioxidant Activity of Peanut Bioactive Peptides

[ Objective] To prepare peanut bioactive peptides and analyze their molecular weight composition and antioxidant activity. [ Method ] The dialysis bag of 8.0, 3.5 and 1.0 kD were used to classify the hydrolyzate derived from alcalase and flavourzyme, peanut bioactive poptides of differ-ent molecular weight were obtained and then their scavenging capacity of free radicals was measured. The molecular weight composition was stud-ied by Tricine-SDS-PAGE.[Result] The content of peptides 〈 1.0 kD were 76.21% and 83.42% in the total hydrolyzate from alcalase and fla-vourzyme respectively. All hydrolyzate with different molecular grades showed free radical scavenging capacity, which was increased with the reduc- tion of molecular mass. The peptides 〈 1.0 kD exhibited higher radical scavenging capacity of （87.41 ±0.66） % （alcalase） and （67.88 ±0.48）% （ flavourzyme）, respectively. [ Conclusion] Peanut bioactive peptides had strong effect of antioxidant capacity, especially that 〈 1.0 kD, which had great prospect.

Effect of 30%Xiange Oceanic Bioactive Peptide Pesticide-Fertilizer on Sugarcane Pests,Sugarcane Yield and Sugar

[Objective]The paper was to study the effect of 30%Xiange oceanic bioactive peptide pesticide-fertilizer on sugarcane pests,sugarcane yield and sugar.[Method]With conventional compound fertilizer mixed with 3%carbofuran granulated insecticide as the control,the field effect of30%Xiange pesticide-fertilizer on sugarcane was compared.[Result]After the application of 30%Xiange pesticide-fertilizer for 90 d,the control effects on sugarcane borers in the two test points were 93.66%and 93.09%,respectively,which were significantly higher than those of conventional control(21.86%and 24.19%).Before harvest,the reduction effects of sugarcane internodes in the two test points treated by pesticide-fertilizer were6.21%and 5.10%,respectively,which were significantly lower than those of conventional control(36.25%and 34.55%).The control effects of Xiange pesticide-fertilizer on sugarcane chafer in the two test points were 91.34%and 100.00%respectively,which were significantly higher than those of conventional control(68.00%and 64.29%).The yields of sugarcane treated by Xiange pesticide-fertilizer in the two test points were107700 and 108000 kg/hm2,and the sugar contents were 15.62%and 15.55%,respectively.The yield and sugar content of sugarcane treated by Xiange pesticide-fertilizer were increased by 28.63%and 1.33%compared with those of conventional control.[Conclusion]30%Xiange oceanic bioactive peptide pesticide-fertilizer has good control effect on sugarcane pests,which could obviously increase yield and sugar of sugarcane.The product is worth being promoted and applied in sugarcane planting area.

Bioactive peptides in fermented foods and their application:a critical review

Bioactive peptides are released during the production of fermented dairy,vegetables,fruits,legumes,fish,and meat prod-ucts.The proteolytic specificity of lactic acid bacteria,Bacillus spp.,yeasts,and mold,apart from their ability to synthesize bioactive peptides,plays an important role in the generation of specific bioactive peptides in traditional fermented foods.Controlled fermentation using defined starter strains has been explored for the development of bioactive peptides enriched novel fermented foods with potential functionality.Bioactive peptides enriched foods exert diverse health benefits,such as antioxidant,antihypertensive,antidiabetic,and immunomodulatory effects.Bioactive peptides can be used as alternatives to synthetic compounds due to negligible side effects and high valuation in the nutraceutical and functional food market.However,challenges associated with the identification,quantification,organoleptic properties,and bioavailability of bioac-tive peptides need to be addressed before exploiting the potential of bioactive peptides in the functional food industry.In the present review,we have discussed the production of bioactive peptides in diverse fermented foods.Structural and sequence specificity of peptides and their effect on the expression of distinct health beneficial effects have been described.The potential of utilizing these bioactive peptides for the development of novel functional fermented foods is discussed.Recent advances in peptide identification,quantification,debittering of peptides,and increasing peptide bioavailability have been explained.

Virtual screening and directional preparation of xanthine oxidase inhibitory peptides derived from hemp seed protein

The traditional nutritional and medical hemp(Cannabis sativa L.)seed protein were explored for the discovery and directional preparation of new xanthine oxidase inhibitory(XOI)peptides by structure-based virtual screening,compound synthesis,in vitro bioassay and proteolysis.Six subtypes of hemp seed edestin and albumin were in silico hydrolyzed by 29 proteases,and 192 encrypted bioactive peptides were screened out.Six peptides showed to be XOI peptides,of which four(about 67%)were released by elastase hydrolysis.The peptide DDNPRRFY displayed the highest XOI activity(IC50=(2.10±0.06)mg/mL),acting as a mixed inhibitor.The pancreatic elastase directionally prepared XOI hemp seed protein hydrolysates,from which 6 high-abundance XOI peptides encrypted 3 virtually-screened ones including the DDNPRRFY.The novel outstanding hemp seed protein-derived XOI peptides and their virtual screening and directed preparation methods provide a promising and applicable approach to conveniently and efficiently explore food-derived bioactive peptides.

Re-Densification Effect of Pressure-Injected Peptide-Hyaluronic Acid Combination on Male Androgenic Alopecia

Introduction: Mechanism of male androgenic alopecia (MAGA) is complex and leads to an excessive hair shedding and decreased hair density. Oral, topical, and injectable autologous treatments demonstrate ability to stimulate hair re-growth, but the response is suboptimal or plateaus off. Synthetic combination of the peptide complex and hyaluronic acid (P-HA) demonstrated hair regrowth in alopecia patients. Electronically-operated pneumatic injections (EPI) generate micro-trauma in the dermis and under wound-healing conditions may enhance regeneration effect of P-HA. Methods: Subjects seeking improvement of their male pattern hair loss (Hamilton-Norwood type 2-4) received the P-HA treatments through EPI. The course included 4 treatments every two weeks over the 8-week period. In 6 months, the hair growth was assessed comparative to baseline by global clinical photography and digital phototrichograms. The treatment safety and tolerability were documented through the whole study period. Results: Twelve men (30-45 years old) completed the treatment course with high tolerability and without adverse events. Post-treatment assessment of the previously bald areas showed improved coverage on the clinical photographs. The phototrichograms demonstrated statistically significant increase in terminal hair density by 36%, cumulative hair thickness by 37%, and follicular units by 20%;all contributing to a 38% increase in cumulated hair density (all p Conclusion: Electronic pneumatic injections are well tolerated and can be safely used for the needle-free administration of the peptide-hyaluronic acid combination in MAGA therapy. We achieved significant hair re-densification in the balding scalp. The exact role of the EPI-induced impact in the hair re-growth mechanism remains to be ascertained. .

Potential antioxidant bioactive peptides from camel milk proteins

Camel milk is traditionally considered to have medicinal characteristics that it has potential health benefits and could help to treat several illnesses. Particularly, it is closest to human breast milk and has high levels of nutrients and bioactive components. The aim of this study was to explore the antioxidant peptides derived from protein fractions of camel milk. Camel milk proteins(CMP) were fractionated into camel casein protein(CCP) and camel whey protein(CWP), which were hydrolyzed with pepsin to produce peptic digests P-CCP and P-CWP, respectively. RP-HPLC was used for fractionation of the peptides from the P-CCP and P-CWP. The antioxidant activities were evaluated using superoxide anion generating system of xanthine oxidase(XOD)and 2,2-diphenyl-1-picrylhydrazyl(DPPH) scavenging assay. Active peptides were analyzed using matrixassisted laser desorption ionization time of flight mass spectrometry(MALDI-TOF-MS) whereas a number of antioxidant peptides, with masses ranging from 913 to 2,951 Da, derived mainly from alpha-casein, lactophorin and lactoferrin, were identified. When yeast cells are used as a system for modeling mitochondrial disease, the peptides in caseins and whey fractions significantly enhanced the tolerance of yeast cells against peroxide-induced oxidative stress. The results show that both caseins and whey proteins of camel milk possess bioactive peptides with significant radical-scavenging activities and thus herald a fascinating opportunity for their potential as nutraceuticals or therapeutic peptides for prevention and treatment of oxidative stress-associated diseases.

Effects of periodical application of bioactive peptides derived from cottonseed on performance,immunity,total antioxidant activity of serum and intestinal development of broilers

This experiment aimed to examine the effect of periodical application of bioactive peptides derived from cottonseed(BPC)in comparison with using sub-therapeutic doses of lincomycin and the excessive in-clusion of vitamin E on performance,immunity,total antioxidant capacity of serum and intestinal morphology of broiler chickens.A total of 240 one-d-old male broiler chicks with similar initial weight(Ross strain)were randomly assigned to 6 groups(8 chicks/pen):non-treated group(basal diet),basal diet supplemented with 2 mg/kg lincomycin,basal diet supplemented with 50 IU vitamin E,basal diet supplemented with 6 g BPC/kg in starter period,basal diet supplemented with 6 g BPC/kg in starter and grower periods and basal diet supplemented with 6 g BPC/kg throughout the whole experiment.The highest final body weight was obtained in the group supplemented with BPC in starter and grower periods.In the finisher phase,broilers fed the diet containing BPC in the starter period and in the whole trial had significantly(P<0.05)better feed conversion ratios(FCR).Jejunal villus height was significantly elevated in broilers supplemented with antibiotic(P<0.001),furthermore it tended to be greater in broilers fed BPC in the starter period.The jejunal villus height-to-crypt depth ratio was significantly(P<0.01)higher in broilers fed the diet containing antibiotic in comparison to other groups.Humoral immune response against Newcastle disease vaccine tended to be elevated in broilers fed the diet containing BPC in the whole trial(P>0.05).Broilers supplemented with BPC in starter and grower,and in the whole trial had significantly(P<0.05)higher antibody titers against sheep red blood cells(SRBC).The highest total antioxidant capacity was obtained in broilers supplemented with the excessive level of vitamin E,furthermore it tended to improve in broilers fed the diet containing BPC in the whole trial.In summary,the results of the study indicated that addition of BPC in broiler diets in the whole trial could improve FCR,immune responses and total antioxidant activity of serum,and BPC could be used in broiler diets as an alternative to in-feed antibiotics.

A comprehensive review on bioactive peptides derived from milk and milkproducts of minor dairy species

Milk from different species has been exploited for the isolation of various functional ingredients for decades.Irrespective of the source,milk is considered as a complete food,as it provides essential nutrients required by the human body.Proteins and their fractions are valuable sources of bioactive peptides that might exert a health beneficial role in the human body such as immune-modulation,antioxidant activity,ACE-inhibitory activity,anti-neoplastic,anti-microbial,etc.In milk,bioactive peptides may either be present in their natural form or released from their parental proteins due to enzymatic action.The increasing interest in bioactive peptides among researchers has lately augmented the exploration of minor dairy species such as sheep,goat,camel,mithun,mare,and donkey.Alternative to cow,milk from minor dairy species have also been proven to be healthier from infancy to older age owing to their higher digestibility and other nutritive components.Therefore,realizing the significance of milk from such species and incentivized interest towards the derivatization of bioactive peptides,the present review highlights the significant research achievements on bioactive peptides from milk and milk products of minor dairy species.

Effects of dairy bioactive peptides and lotus seeds/lily bulb powder on flavor and quality characteristics of goat milk yogurt

The objective of this study was to evaluate the changes on flavor and quality characteristics of goat yogurt during storage with the addition of dairy bioactive peptides and a mixture of lotus seed and lily bulb powder.Both the addition of dairy bioactive peptides and lotus seeds/lily bulb powder resulted in a fermentation time reduction,water holding capacity(WHC)improvement,and inhibition of post-acidification of goat yogurt during storage.A total of 50 volatile flavor components were detected in the goat milk yogurt samples,and the addition of the above two supplements were shown to be effective in improving the flavor and the textural properties of the goat milk yogurt during storage.The group added with lotus seeds/lily bulb powder showed the best WHC and textural properties,followed by the group added with dairy bioactive peptides alone and the group with both added.The addition of both supplements was found to be useful in making up for the two defects of goat yogurt,prolonged fermentation and soft curds.Therefore,dairy bioactive peptides and lotus seeds/lily bulb powder are recommended to be added to goat yogurt as nutritional supplements.

Review on plant-derived bioactive peptides:biological activities,mechanism of action and utilizations in food development

Plant proteins are good alternative to animal sources in bioactive peptide production due to their safety,low-cost,rich resources and easy for large scale production.The bioactivities of the peptides derived from plant proteins including antihypertensive,hypocholesterolemic,immunomodulatory,antioxidant,antimicrobial,anti-diabetic,opiate and hepatoprotective effect are being increasingly recognized with regards to health promoting and disease prevention.In addition to bioactivities,the plant-derived bioactive peptides possess various functional properties including emulsifying and foaming properties,and water and oil retention capacities owning to the hydrophilic/lipophilic property,conformational flexibility and chain length of peptides.Hence,the plant-derived bioactive peptides are promising ingredients for the development of health-care and functional products.This review provides the research progress on the biological activities and functional properties of plant derived peptides.The mechanism of action and structure-activity relationships of the bioactive peptide were also described,when known.Furthermore,recent developments,major challenges and prospect in the application of the plant-derive bioactive peptides in the development of functional products are discussed and summarized.The objective of this review is to improve the understanding of plant-derive bioactive peptides,and provide some constructive inspirations for further research and industrial application in the food and medicine industry.

The alteration of gut microbiota by bioactive peptides:a review

Evidences suggest that the homeostasis of gut microbiota is among the most important factors for maintaining the physical and mental health of the host.Among the multiple factors affecting the homeostasis of gut microbiota,diet is one of the decisive factors.Bioactive peptides derived from protein hydrolyzed by protease or fermented by microorganism have many physiological activities that their parent proteins do not have.Currently,bioactive peptides attract more and more attention due to their bidirectional interaction with gut microbes.It has been reported that some bioactive peptides could alter the composition of gut microbiota by influencing the intestinal microenvironment.Meanwhile,quite a few bioactive peptides that are released by gut microbes or intestinal cells could resist the pathogenic bacteria to sustain the homeostasis of gut microbiota.In this review,some exogenous bioactive peptides derived from food and some endogenous bioactive peptides released from intestinal cells or microbes were discussed to summary their effects on the modulation of gut microbiota.This review is expected to provide new ideas for related research,and as well to promote the application of bioactive peptides in the fields of food and medicine.

A new peptide,VD11,promotes structural and functional recovery after spinal cord injury

The regenerative capacity of the central nervous system is very limited and few effective treatments are currently available for spinal cord injury.It is therefore a priority to develop new drugs that can promote structural and functional recovery after spinal cord injury.Previous studies have shown that peptides can promote substantial repair and regeneration of injured tissue.While amphibians have a pronounced ability to regenerate the spinal cord,few studies have investigated the effect of amphibian spinal cord-derived peptides on spinal cord injury.Here we report for the first time the successful identification and isolation of a new polypeptide,VD11(amino acid sequence:VDELWPPWLPC),from the spinal cord of an endemic Chinese amphibian(Odorrana schmackeri).In vitro experiments showed that VD11 promoted the secretion of nerve growth factor and brain-derived neurotrophic factor in BV2 cells stimulated with lipopolysaccharide,as well as the proliferation and synaptic elongation of PC12 cells subjected to hypoxia.In vivo experiments showed that intravertebral injection of VD11 markedly promoted recovery of motor function in rats with spinal cord injury,alleviated pathological damage,and promoted axonal regeneration.Furthermore,RNA sequencing and western blotting showed that VD11 may affect spinal cord injury through activation of the AMPK and AKT signaling pathways.In summary,we discovered a novel amphibian-derived peptide that promotes structural and functional recovery after spinal cord injury.