Effect of growth hormone-releasing peptide on cardiac cholinergic nerve fiber density distribution in a rat model of heart failure

BACKGROUND： Changes in the cardiac autonomic nerve are considered to be important factors in the mechanisms of heart failure. It is possible to reduce or slow down nerve degeneration and necrosis, provided that patients take effective neuroprotectants during the early stages of heart failure. Moreover, it is possible to relieve the pathological process and reduce the risk of death. OBJECTIVE： To study the effect of growth hormone releasing peptide （GHRP） on cardiac cholinergic nerve fiber density distribution in a rat model of heart failure, and verify whether GHRP can ameliorate denervation. DESIGN, TIME AND SETTING： A randomized controlled study was performed at the Key Laboratory of Anatomy, Harbin Medical University, between June and October 2009. MATERIALS： Fifty adult, healthy, female, Wistar rats, weighing （200± 20） g, were randomly divided into GHRP （n = 30）, model （n = 10）, and sham operation （n = 10） groups. GHRP-2 was made in Shanghai, China （batch No. z071212-03）. METHODS： Acute myocardial infarction was established by ligating the left anterior descending coronary artery in the GHRP and model groups. Five weeks later, myocardial function was detected using color ultrasound electrocardiograph a successful marker of chronic heart failure models Ejection fraction 〈 60% was considered to be However, the left anterior descending coronary artery was not ligated in the sham operation group. The GHRP group was injected with 100 μ g/kg GHRP-2, and the other two groups were injected with the same volume of physiological saline, once per day. MAIN OUTCOME MEASURES： After 4 weeks, pathological changes in cardiac cholinergic nerve fibers were detected under optic microscopy following hematoxylin/eosin staining. In addition, density distribution was measured using a multi-function color pathological image system. RESULTS： In the sham operation group, myocardial cells were regular, uniformly stained, and no inflammatory cells were present. In the model group, myocardial cells were unevenly stained, exhibited nuclear atrophy, degeneration, dissolution, or disappearance. In the GHRP group, myocardial damage was less than in the model group; cardiac muscle fibers exhibited slight degeneration. The myocardium in the sham operation group was serried, spreading the cholinergic innervations along the cardiac fiber. In the model group, there was a decreased number of cholinergic nerve fibers decreased, which also became shorter and smaller, compared with the sham operation group （P 〈 0.01）. In the GHRP group, cholinergic positive nerve fibers were significantly increased compared with the model group （P 〈 0.01）, but still less than the sham surgery group （P 〈 0.05）. CONCLUSION： GHRP delayed denervation and reduced nerve reconstitution following heart failure in rats.

Isolation of Growth Hormone-Releasing Hormone and Its Receptor Genes from Scatophagus argus and Their Expression Analyses

The teleost Scatophagus argus is a species whose females grows faster than males.Growth hormone(gh)mRNA abundance in females pituitary is higher than that in males;however the mechanism underlining such differential is still unknown.Growth hormone(GH)is tightly associated with GH-releasing hormone(Ghrh)in vertebrates.In this study,Ghrh gene(ghrh)and its receptor gene,ghrhr,were isolated from S.argus.Tissue expression analysis showed that ghrh and ghrhr were mainly expressed in hypothalamus while ghrhr was expressed in pituitary and gh was predominantly expressed in pituitary.Twenty cultured S.argus individuals were used to compare ghrh,ghrhr and gh mRNA abundances,120 g and 181 g average weight for male(n=11)and female(n=9),respectively.Real-time PCR indicated that the ghrh and ghrhr mRNA abundances in male hypothalamus were significantly higher than those in female hypothalamus while that of gh mRNA abundance was significantly higher in female pituitary than in male pituitary.The ghrh and ghrhr mRNA abundances were significantly up-regulated in female hypothalamus 3 h after injection of 0.1 mg kg^-1 body weight Ghrh while pituitary ghrhr and gh mRNA abundances were not affected.In female hypothalamus,ghrh and ghrhr m RNA abundances were not affected at 6 h post-injection of 4 mg kg^-1 body weight 17α-methyltes-tosterone(17α-MT)or 17β-Estradiol(E2).In female pituitary,ghrhr m RNA abundance was down-regulated by 17α-MT while that of gh m RNA abundance was up-regulated by E2.Our findings indicated that E2,rather than Ghrh,plays an important role in up-regulating the expression of gh in female S.argus,which should aid to understand the sexual dimorphism of teleost growth.

Gastric motor effects of ghrelin and growth hormone releasing peptide 6 in diabetic mice with gastroparesis

AIM:To investigate the potential therapeutic significance of ghrelin and growth hormone releasing peptide 6 (GHRP-6) in diabetic mice with gastric motility disorders. METHODS: A diabetic mouse model was established by intraperitoneal (ip) injection of alloxan. Diabetic mice were injected ip with ghrelin or GHRP-6 (20-200 μg/kg), and the effects on gastric emptying were measured after intragastric application of phenol red. The effect of atropine, NG-nitro-L-arginine methyl ester hydrochloride (L-NAME) or D-Lys3-GHRP-6 (a growth hormone secretagogue receptor (GHS-R) antagonist) on the gastroprokinetic effect of ghrelin or GHRP-6 (100 μg/kg) was also investigated. The effects of ghrelin or GHRP-6 (0.01-10 μmol/L) on spontaneous or carbachol-induced contractile amplitude were also investigated in vitro, in gastric fundic circular strips taken from diabetic mice. The presence of growth hormone secretagogue receptor 1a transcripts in the fundic strips of diabetic mice was detected by reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: We established a diabetic mouse model with delayed gastric emptying. Ghrelin and GHRP-6 accelerated gastric emptying in diabetic mice with gastroparesis. In the presence of atropine or L-NAME, which delayed gastric emptying, ghrelin and GHRP-6 (100 μg/kg) failed to accelerate gastric emptying. D-Lys3-GHRP-6 also delayed gastric emptying induced by the GHS-R agonist. Ghrelin and GHRP-6 increased the carbachol-induced contractile amplitude in gastric fundicstrips taken from diabetic mice. RT-PCR confirmed the presence of GHS-R mRNA in the strip preparations. CONCLUSION: Ghrelin and GHRP-6 increase gastric emptying in diabetic mice with gastroparesis, perhaps by activating peripheral cholinergic pathways in the enteric nervous system.

The prolonged effect of glucagon-like peptide 2 pretreatment on growth performance and intestinal development of weaned piglets

Background： Glucagon-like peptide 2 （GLP-2） is a potent epithelium-specific intestinal growth factor. The aim of this study was to demonstrate the prolonged effect of GLP-2 on the growth performance of weaned piglets. Forty piglets weaned at the age of 28 d with an average BW of 6.8 ＋ 0.4 kg were assigned to four treatments： （i） non- challenged control; （ii） LPS-challenged control; （iii） LPS ＋ low GLP-2; and （iv） LPS ＋ high GLP-2. Piglets in groups （i）, （ii）, and （iv） were s.c. injected with PBS supplemented with human [Gly2]GLP-21-34 at doses of 0, 2 and 10 nmol/kg BW per day for seven consecutive days. BW, gain：feed ratio （G：F）, and plasma GLP-2 levels were determined on d 0 7, and 14 after weaning. Piglets were challenged with i.p. administration of Escherichia coil lipopolysaccharide （LPS） at a dose of 100 pg/kg on d 14 to induce intestinal damage. Twenty-four hours later, intestinal tract samples were collected to assess intestinal morphology and quantify enzyme activity. Results： Plasma GLP-2 levels decreased after weaning, but in the high GLP-2 group, plasma GLP-2 was maintained on d 7 and even increased to a level higher than the preweaning level on d ]4 （P 〈 0.05）. High GLP-2 treatment significantly increased the duodenal, jejunal and ileal weight, as well as the gross weight of the small intestine （SI）, and the SI weight index （P 〈 0.05）. LPS caused villous atrophy and disrupted intestinal morphology in the duodenum, jejunum and ileum. GLP-2 also significantly increased the villus height and the villus height/crypt depth ratio （VCR） of the duodenum, jejunum, and ileum （P 〈 0.05）. Histological examination revealed that in GLP-2-treated groups, the integrity of the villus was maintained, and the villus was protected against LPS-induced damage. GLP-2 significantly increased the activity of alkaline phosphatase （AKP）, y-glutamyltranspeptidase （y-G-i-）, and pancreatic lipase in the duodenum and jejunum （P 〈 0.05）. GLP-2 treatment also significantly increased the average daily gain （ADG） and G：F of piglets at 0 to 7, 7 to 14, as well as 0 to14 d （P 〈 0.05）, resulting in a significant increase of final 8W in high GLP-2 pigs （P = 0.016）. Conclusions： Exogenous GLP-2 improved the growth of weaned piglets and protected them against LPS-induced intestinal damage. These effects may be due to the ability of GLP-2 to promote the secretion of endogenous GLP-2 to stimulate the small intestinal development.

Effect of calcitonin gene-related peptide and nerve growth factor on spatial learning and memory abilities of rats following focal cerebral ischemia/reperfusion

BACKGROUND: Calcitonin gene-related peptide (CGRP) and nerve growth actor (NGF) cam improve spatial learning and memory abilities of rats with cerebral ischemia/reperfusion; however, the effect of combination of them on relieving learning and memory injury following cerebral ischemia/reperfusion should be further studied. OBJECTIVE: To study the effects of exogenous CGRP and NGF on learning and memory abilities of rats with focal cerebral ischemia/reperfusion. DESIGN: Randomized controlled animal study. SETTING: Department of Neurosurgery, the Second Hospital of Xiamen; Department of Neurosurgery, the Second Affiliated Hospital of China Medical University; Department of Neurobiology, Basic Medical College of China Medical University. MATERIALS: A total of 30 healthy male SD rats, aged 8 weeks, of clean grade, weighing 250-300 g, were provided by Experimental Animal Department of China Medical University. All rats were randomly divided into sham-operation group, ischemia/reperfusion group and treatment group with 10 in each group. The main reagents were detailed as the follows: 100 g/L chloral hydrate, 0.5 mL CGRP (2 mg/L, Sigma Company, USA), and NGF (1× 106 U/L, 0.5 mL, Siweite Company, Dalian). METHODS: The experiment was carried out in the Department of Neurobiology, Basic Medical College of China Medical University from February to July 2005. Rat models of middle cerebral artery occlusion were established by method of occlusion, 2 hours after that rats were anesthetized and the thread was slightly drawn out for 10 mm under direct staring to perform reperfusion. Rats in the ischemia/reperfusion group received intraperitoneal injection of 1 mL saline via the abdomen at two hours later, while rats in the treatment group at 2 hours later received intraperitoneal injection of 2 mg/L CGRP (0.5 mL) and 1×106 U/L NGF (0.5 mL) once a day for 10 successive days. First administration was accomplished within 15 minutes after ischemia/reperfusion. Rats in the sham-operation group were separated of the vessels without occlusion or administration. The neural function was evaluated with Zea Longa 5-grade scale. Animals with the score of one, two and three points received Morris water-maze test to measure searching time on platform (omitting platform-escaping latency). Meanwhile, leaning and memory abilities of animals were reflected through testing times of passing through platform per minute. MAIN OUTCOME MEASURES: Experimental results of omitting platform-escaping latency and spatial probe. RESULTS: Three and two rats in the ischemia/reperfusion group and treatment group respectively were not in accordance with the criteria in the process, and the rest were involved in the final analysis. ① Comparisons of platform-escaping latency during Morris water-maze test in all the three groups: Ten days after modeling, the platform-escaping latency in the ischemia/reperfusion group was obviously longer than that in sham-operation group (P < 0.01), and was significantly shorter than that in the treatment group (P < 0.01). ② Comparisons of times of passing through platform in all the three groups: Times of passing through platform were remarkably less in the ischemia/reperfusion group than those in the sham-operation group [(1.79±0.39), (4.30±0.73) times/minute, P < 0.01], and those were markedly more in the treatment group than the ischemia/reperfusion group [(3.16±1.03), (1.79±0.39) times/minute, P < 0.01]. CONCLUSION: CGRP and NGF are capable of ameliorating the abilities of spatial learning and memory in MCAO rats, which indicates that CGRP and NGF can protect ischemic neurons.

BDNF pro-peptide：a novel synaptic modulator generated as an N-terminal fragment from the BDNF precursor by proteolytic processing

Most growth factors are initially synthesized as precursors and it was cleaved into bioactive mature domain and pro-domain.However,compared with the expression and function of bioactive mature domain,the biological role of the pro-domain is poorly understood.Unexpectedly,we found that the pro-domain（or pro-peptide）of brain-derived neurotrophic factor（BDNF）,which is well-known neurotrophic factor in brain,has a potential ability to facilitate hippocampal long-term depression.Furthermore,a BDNF polymorphism Val66Met,which substitute valine into methionine at 66 amino acid,impacted the biological activity of the BDNF pro-peptide.We lastly discuss the possible roles of BDNF and its pro-peptide in the generation of neural stem cells and progress of ischemia.

Gecko crude peptides inhibit migration and lymphangiogenesis by down regulating the expression of VEGF-C in human hepatocellular carcinoma cells and human lymphatic endothelial cells

OBJECTIVE To explore the role of gecko crude peptides(GCPs)in the proliferation,apoptosis,migration and lymphangiogenesis of human hepatocellular carcinoma cells(Hep G2)and human lymphaticendothelial cells(HLECs)in vitro.METHODS The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay was used to evaluate the anti-proliferative effect of GCPs and si RNA-VEGF-C on Hep G2 cells,Hoechst 33258 staining and flow cytometry were performed to analyze cycle and apoptosis.The migration and invasion ability of cells were assayed by transwell chamber experiment and wound-healing assay.The protein and m RNA expressions of vascular endothelial growth factor-C(VEGF-C)and CXC chemokine receptor-4(CXCR4)were detected by q-PCR,immunofluorescence,Western blot.The protein expressions of the extracellular signal regulated kinase(ERKI/2),c-Jun N-terminal kinase(JNK),p38-mitogen activated protein kinases(p38 MAPK),serine/threonine kinase(Akt)and phosphatidylinositol-3-kinase(PI3K)were detected by western blot.The anti-lymphangiogenesis effect of GCPs on the HLECs was analyzed using an in vitro tube-formation assay.The protein and m RNA expressions of vascular endothelial growth factor receptor-3(VEGFR-3)and stromal cell-derived factor-1(SDF-1)were detected by q-PCR,Western blot.RESULTS GCPs and si RNA-VEGF-C inhibited Hep G2 proliferation,invasion and migration,and the most obvious inhibitory effect was both synergistic effects.Thus,GCPs suppressed HLECs proliferation,migration and tubelike structure formationin a dose-dependent manner,and had inhibitory effect of tumor-induced lymphangiogenesis in vitro.Additionally,we found that GCPs and si RNA-VEGF-C decreased the expressions of MMP-2,MMP-9,VEGF-C,CXCR4,phospho-ERK1/2,phospho-P38,phospho-JNK and PI3K in Hep G2 cells.Moreover,GCPs had a dose-dependent depressive effecton the expressions of VEGFR-3,SDF-1 in HLECs.CONCLUSION The low expression of VEGF-C mediated by si RNA-VEGF-C and GCPs inhibit tumor proliferation,invasion and migrationby suppressing the MAPK signaling pathway through reduced levels of VEGF-C,and GCPs inhibit tumor lymphangiogenesis by suppressing the CXCR4/SDF-1 signaling pathway through suppressed VEGF-C/VEGFR-3.

Chondrogenesis of Precartilaginous Stem Cells in KLD-12 Self-assembling Peptide Nanofiber Scaffold Loading TGF-β3 Gene

The effect of culture in KLD-12 self-assembling peptide nanofiber scaffold containing TGF-β3 gene on differentiation of precartilaginous stem cells （PSCs） into chondrocytes was studied. KLD-12 was synthesized by solid-state method. After TGF-β3 plasmid was loaded into KLD-12 self-assembling peptide nanofiber scaffold, DNA release ability was investigated. PSCs and hTGF-β3 gene were loaded into KLD-12 3-D scaffold, and MTT assay was performed to investigate the cell proliferation, and ELASA assay was used to investigate the expression of TGF-β3. Specific cartilage matrix was examined by quantitative real-time PCR, immunohistochemistry and Alcian Blue staining. Compared with control group, DNA synthesis level of PSCs reached the peak within 3 days when PSCs were cultured in self-assembling peptide nanofiber scaffold loading TGF-β3 plasmid, and maintained this high level within 2 weeks. MTT results showed that the proliferation ability of experimental group was statistically higher than that in control group （P〈0.05）. Quantitative real-time PCR suggested that the percentage of TGF-β3 positive PSCs in experimental group was higher than that in control group （P〈0.01）. ELISA assay showed that the TGF-β3 protein level increased in supernatant of experimental group＇s PSCs, reached the peak after 72 h and then declined a little to the plateau phase. Compared with the control group, the specific gene of chondrocyte typical extracellular matrix significantly up-regulated （P〈0.01）. The results showed that PSCs differentiated into chondrocytes in self-assembling peptide nanofiber scaffold loading TGF-β3 plasmid, which provided a fresh approach to cartilage tissue engineering.

Genome-wide identification and functional characterization of the MdCLE peptide family in apple(Malus×domestica)

The CLAVATA3/EMBRYO SURROUNDING REGION-related(CLE)peptides are critical for stem cell homeostasis in plant shoot and root apical meristem.Although CLE genes have been reported in numerous plants,there is limited information for apple.Here,twenty-five MdCLE genes were identified fromapple genome(Apple Genome V1.0 predicted peptides).Analysis of chromosomal location showed that the 25 MdCLE genes were located on 12 of 17 apple chromosomes.Genetic structure analysis showed that 21 of 25 the MdCLE genes were intron-free.Expression patterns showed thatmost of the MdCLE genes showed higher expression levels in leaves and root compared with the other tissues.In addition,expression analysis demonstrated that MdCLE genes had different gene expression patterns for abiotic stress treatment,suggesting their potential roles in acclimation of apple to adverse environments.The 25 MdCLE genes encoded 19 different CLE peptides,and they were divided into two groups depending on their effects on the inhibition of Arabidopsis root growth.Our results suggest that MdCLE genesmay have an important but redundant function in regulating plant growth and development,and this work provides valuable references for further investigation of the biological functions of MdCLE genes.

Antimicrobial peptides act on the rumen the performance of castrated bulls

Background Many countries have already banned the use of antibiotics in animal husbandry,making it extremely difficult to maintain animal health in livestock breeding.In the livestock industry,there is an urgent need to develop alternatives to antibiotics which will not lead to drug resistance on prolonged use.In this study,eighteen castrated bulls were randomly divided into two groups.The control group(CK)was fed the basal diet,while the antimicrobial peptide group(AP)was fed the basal diet supplemented with 8 g of antimicrobial peptides in the basal diet for the experimental period of 270 d.They were then slaughtered to measure production performance,and the ruminal contents were isolated for metagenomic and metabolome sequencing analysis.Result The results showed that antimicrobial peptides could improve the daily weight,carcass weight,and net meat weight of the experimental animals.Additionally,the rumen papillae diameter and the micropapillary density in the AP were significantly greater than those in the CK.Furthermore,the determination of digestive enzymes and fermentation parameters showed that the contents of protease,xylanase,andβ-glucoside in the AP were greater than those in the CK.However,lipase content in the CK was greater than that in the AP.Moreover,the content of acetate,propionate,butyrate,and valerate was found to be greater in AP than those in CK.The metagenomic analysis annotated 1993 differential microorganisms at the species level.The KEGG enrichment of these microorganisms revealed that the enrichment of drug resistance-related pathways was dramatically decreased in the AP,whereas the enrichment of immune-related pathways was significantly increased.There was also a significant reduction in the types of viruses in the AP.187 probiotics with significant differences were found,135 of which were higher in AP than in CK.It was also found that the antimicrobial mechanism of the antimicrobial peptides was quite specific.Seven low-abundance microorganisms(Acinetobactersp.Ac1271,Aequorivita soesokkakensis,Bacillus lacisalsi,Haloferax larsenii,Lysinibacillussp.3DF0063,Parabacteroidessp.217,Streptomycessp.So13.3)were found to regulate growth performance of the bull negatively.Metabolome analysis identified 45 differentially differential metabolites that significantly different between the CK and the AP groups.Seven upregulated metabolites(4-pyridoxic acid,Ala-Phe,3-ureidopropionate,hippuric acid,terephthalic acid,L-alanine,uridine 5-monophosphate)improve the growth performance of the experimental animals.To detect the interactions between the rumen microbiome and metabolism,we associated the rumen microbiome with the metabolome and found that negative regulation between the above 7 microorganisms and 7 metabolites.Conclusions This study shows that antimicrobial peptides can improve the growth performance of animals while resisting viruses and harmful bacteria and are expected to become healthy alternatives to antibiotics.We demonstrated a new antimicrobial peptides pharmacological model.We demonstrated low-abundance microorganisms may play a role by regulating the content of metabolites.

Preclinical therapy of benign prostatic hyperplasia with neuropeptide hormone antagonists

Benign prostatic hyperplasia(BPH)is a pathologic condition of the prostate described as a substantial increase in its number of epithelial and stromal cells.BPH may significantly reduce the quality of life due to the initiation of bladder outlet obstruction and lower urinary tract syndromes.Current medical therapies mostly consist of inhibitors of 5α-reductase orα1-adrenergic blockers;their efficacy is often insufficient.Antagonistic analogs of neuropeptide hormones are novel candidates for the management of BPH.At first,antagonists of luteinizing hormone-releasing hormone(LHRH)have been introduced to the therapy aimed to reduce serum testosterone levels.However,they have also been found to produce an inhibitory activity on local LHRH receptors in the prostate as well as impotence and other related side effects.Since then,several preclinical and clinical studies reported the favorable effects of LHRH antagonists in BPH.In contrast,antagonists of growth hormone-releasing hormone(GHRH)and gastrin-releasing peptide(GRP)have been tested only in preclinical settings and produce significant reduction in prostate size in experimental models of BPH.They act at least in part,by blocking the action of respective ligands produced locally on prostates through their respective receptors in the prostate,and by inhibition of autocrine insulin-like growth factors-Ⅰ/Ⅱand epidermal growth factor production.GHRH and LHRH antagonists were also tested in combination resulting in a cumulative effect that was greater than that of each alone.This article will review the numerous studies that demonstrate the beneficial effects of antagonistic analogs of LHRH,GHRH and GRP in BPH,as well as suggesting a potential role for somatostatin analogs in experimental therapies.

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.

Antitumor Effect of Cationic INKKI Peptide from Bovine <i>β</i>-Casein on Melanoma B16F10

Cationic peptide with the sequence INKKI 41-45 was isolated from bovine β-casein after tryptic hydrolysis and synthetized. The aim of this work was to evaluate the antiproliferative activity in vitro and antitumor effect in animal model. The in vitro cytotoxicity was evaluated on B16F10 melanoma cells by MTT assay. Detection of apoptosis was measured using the annexin V/PI double staining and cell cycle analysis performed flow cytometry. Caspase-3 activity was analyzed with substrate specific fluorogenic DEVD-MCA. In vivo, antitumor activity was evaluated in B16F10 melanoma tumor-bearing C57BL/6J mice. The animals were treated with 55 mg/kg INKKI administered into peritumoral region, while control group received saline solution. The following antitumor parameters were examined: tumor volume, number of metastases, tumor delayed time, tumor doubling time. Histological analyses were performed with H & E staining. The results showed that INKKI induced dose-response cytotoxicity selective for B16F10 melanoma cells (IC50 1.7 μM) and did not present cytotoxic effects for FN1 fibroblast cells. INKKI-induced apoptosis detected trough of annexin V/PI assay and it was accompanied with an increase of sub-G1 apoptotic fractions and significant increase of caspase-3 cleavage. The tumor-bearing mice treated with INKKI showed a significant reduction in tumor volume of 72.62% and decreased of metastasis number loci. In addition, INKKI caused a significant delay in tumor growth and prolonged the tumor doubling time. Histological analysis revealed an increased of necrosis areas and reduction of tumor cells in tumor treated with INKKI, it was a many hallmark of its antitumor effects observed from in vivo experiments. In conclusion, we show that INKKI is a peptide that could be considered a new putative candidate development to anticancer therapy drug.

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.

Peptides,new tools for plant protection in eco-agriculture

As important physiological regulators,peptides have been used in many fields including medicine,cosmetics,healthcare products,animal nutrition and health,and plant nutrition and protection.In recent years,peptides have become a popular research subject in plant protection as antimicrobial and immune inducers,plant growth regulators,insecticides,and herbicides for their extensive raw material sources,excellent activity,and ideal environmental compatibility.This paper briefly introduces peptide research progress,presents an overview of peptide studies in plant protection,and summarizes the application of the peptides in plant protection and prospects for peptides as green agrochemicals.

Basic fibroblast growth factor attenuates the degeneration of injured spinal cord motor endplates

The distal end of the spinal cord and neuromuscular junction may develop secondary degeneration and damage following spinal cord injury because of the loss of neural connections. In this study, a rat model of spinal cord injury, established using a modified Allen＇s method, was injected with basic fibroblast growth factor solution via subarachnoid catheter. After injection, rats with spinal cord injury displayed higher scores on the Basso, Beattie and Bresnahan locomotor scale. Motor function was also well recovered and hematoxylin-eosin staining showed that spinal glial scar hyperplasia was not apparent. Additionally, anterior tibial muscle fibers slowly, but progressively, atrophied. Immu- nohistochemical staining showed that the absorbance values of calcitonin gene related peptide and acetylcholinesterase in anterior tibial muscle and spinal cord were similar, and injection of basic fi- broblast growth factor increased this absorbance. Results showed that after spinal cord injury, the distal motor neurons and motor endplate degenerated. Changes in calcitonin gene related peptide and acetylcholinesterase in the spinal cord anterior horn motor neurons and motor endplate then occurred that were consistent with this regeneration. Our findings indicate that basic fibroblast growth factor can protect the endplate through gene related peptide and acetylcholinesterase cord. attenuating the decreased expression of calcitonin n anterior horn motor neurons of the injured spinal

Effects of Plant Protein Hydrolysate on Emergence and Growth of Rice Seedlings

With the rise of organic agriculture,researches on the production of slow-release organic fertilizer from natural organic materials have attracted much attention.Plant protein and peptides have potential applications in agricultural production.The effects of bioactive peptides derived from plant protein on rice seed germination and seedling growth and development were systematically studied using bioassays and greenhouse growth experiments.The feasibility of phytoprotein peptide application in the rice seedling stage was discussed.The results showed that the phytoprotein peptides had no adverse effects on rice,and the application when applied to rice seedlings,phytoprotein peptides within a certain concentration range produced obvious promotion effects on the growth and development of rice seedlings,which were more pronounced in the underground part of the plants.Phytoprotein peptides increased root length and dry matter accumulation and improved the robustness of rice seedlings.A 40 g·mol^(-1)·L^(-1) dose of phytoprotein peptides increased root length,plant fresh weight,plant dry weight,root fresh weight and root dry weight by 59.24%,20.14%,26.32%,51.57%and 81.70%,respectively compared to the control.In addition,the phytoprotein peptides significantly increased the chlorophyll content,root activity and nitrate reductase activity of rice seedlings,as well as superoxide dismutase,peroxidase,catalase andβ-1,3-glucanase activity in rice leaves,which could improve stress resistance.Plant peptides were simple to produce and cost-effective.Reasonable development and excavation of plant protein and protein hydrolysate peptide in China's agricultural application had a good practical basis and value significance.

Growth performance,nutrient digestibility,intestinal morphology,cecal mucosal cytokines and serum antioxidant responses of broiler chickens to dietary enzymatically treated yeast and coccidia challenge

Background There is a growing search for natural feed additives to alleviate the deleterious effects of coccidia infection in poultry production.This study aimed to investigate the effect of enzymatically treated yeast(ETY) on the growth performance,nutrient digestibility,intestinal morphology,antioxidative status,and cecal mucosa cytokines of coccidia-challenged broiler chickens.Methods From d 1 to 14 post hatching,480 broiler chickens were allocated to 3 corn-soybean meal-based experimental diets with increasing concentrations of ETY(0,1,or 2 g/kg).The experiment was designed as a randomized complete block design with body weight(BW) used as a blocking factor.On d 14 post hatching,the birds were re-randomized within each of the 3 experimental diets.Each of the 3 diet groups was split into a challenge or no-challenge group.This resulted in a 3 × 2 factorial arrangement of treatments.The coccidia challenge was administered on d 15 by an oral gavage.Results Dietary ETY improved(P < 0.05) the G:F of birds on d 21 regardless of the challenge state and linearly increased(P < 0.01) the apparent ileal digestibility of dry matter(DM),nitrogen,and gross energy(GE).The coccidia challenge decreased(P < 0.05) BW gain and feed intake of broiler chickens and reduced(P < 0.01) the total tract retention of DM,GE,and nitrogen.The coccidia challenge increased(P < 0.01) the mRNA gene expression of TNFα,IL-1β,IL-10,and IL-6 in the cecal mucosa.There was a tendency(P ne = 0.08) for ETY to linearly reduce IL-1β expression.Additionally,ETY supplementation increased(P < 0.05) the geexpression of OCLN.Serum catalase increased(P < 0.05) with dietary ETY in broiler chickens on d 21.Dietary ETY linearly increased(P < 0.05) the ileal villus height to crypt depth ratio,and ileal goblet cell density in broiler chickens.The ileal and excreta oocyst counts decreased(P < 0.01) with increasing supplementation of dietary ETY in coccidia-challenged broiler chickens on d 21.Conclusions Dietary ETY enhanced nutrient utilization and augmented intestinal development in broiler chickens.However,dietary ETY did not completely attenuate the adverse effects of a coccidia challenge in broiler chickens.

抗菌肽对肉牛生长性能及经济效益的影响

试验旨在研究不同水平的抗菌肽对西门塔尔杂交肉牛生长性能、瘤胃发酵参数、血清免疫力及养殖经济效益的影响。试验选择32头健康、体重相近的西门塔尔杂交肉牛,随机分成4组,每组8个重复,每个重复1头肉牛。对照组饲喂基础饲粮,试验A组、B组、C组分别饲喂含有2、4、8 g/(头·d)抗菌肽的饲粮。预试期7 d,正式试验期150 d。结果表明:与对照组比较,试验B组和试验C组的末重和平均日增重显著升高(P<0.05),料重比显著降低(P<0.05);瘤胃液的pH值和菌体蛋白含量显著升高(P<0.05),乙丙比显著降低(P<0.05);所有试验组瘤胃乙酸浓度显著降低(P<0.05);所有试验组血清中白细胞介素-4水平显著升高(P<0.05),白细胞介素-6水平显著降低(P<0.05);试验B组和试验C组血清白细胞介素-10水平显著升高(P<0.05),免疫球蛋白M和免疫球蛋白G水平显著升高(P<0.05)。与对照组相比,试验A组、B组、C组的增重收入分别增加了10.40%、22.34%和23.55%,利润分别增加了19.31%、46.54%和48.45%。研究表明,在肉牛养殖中添加适量的抗菌肽可以提高生长性能,促进瘤胃发酵功能,增强机体的免疫功能,增加养殖利润,且添加4 g/(头·d)的抗菌肽较为适宜。

基于心功能及IGFBP7、sST2、CGRP、ET分析沙库巴曲缬沙坦在治疗冠心病合并慢性心力衰竭中的应用效果

目的 分析冠心病(CHD)合并慢性心力衰竭(CHF)患者应用沙库巴曲缬沙坦治疗的效果。方法 选择2020年1月至2023年1月邯郸市第四医院收治的86例CHD合并CHF患者,以随机数字表法将其分为对照组和试验组各43例。两组CHD治疗均应用硝酸酯类、他汀类及抗血小板药物,对照组CHF治疗应用坎地沙坦酯片、醛固酮受体拮抗剂及β受体阻滞剂,试验组治疗则将对照组中的坎地沙坦酯片替换为沙库巴曲缬沙坦钠片。比较两组疗效、不良反应、心功能指标[左室短轴缩短率(LVFS)、左室射血分数(LVEF)、6min步行距离(6 MWD)]、心室重构指标[Ⅲ型胶原前肽(PⅢP)、层粘蛋白(LN)、基质金属蛋白酶-9(MMP-9)]、心肌损伤和血管内皮功能相关指标[胰岛素样生长因子结合蛋白7(IGFBP7)、可溶性生长刺激表达基因2(sST2)、降钙素基因相关肽(CGRP)、内皮素(ET)]。结果与对照组比,试验组治疗3个月后的总有效率更高,差异有统计学意义(P<0.05)。两组治疗3个月后的LVFS、LVEF、6 MWD、IGFBP7、CGRP与治疗前比升高,且试验组与对照组比更高,差异有统计学意义(P<0.05);PⅢP、LN、MMP-9、sST2、ET降低,试验组与对照组比更低,差异有统计学意义(P<0.05)。两组不良反应总发生率对比差异无统计学意义(P>0.05)。结论 沙库巴曲缬沙坦可有效调节CHD合并CHF患者IGFBP7、sST2、CGRP、ET,改善血管内皮功能、心肌损伤、心室重构及心功能,进而可提高疗效,且具有良好的安全性。