Momordica antiviral protein 30 kD(MAP30)is a type I ribosome-inactivating protein(RIP)with antibacterial,anti-HIV and antitumor activities but lacks the ability to target tumor cells.To increase its tumor-targeting ab...Momordica antiviral protein 30 kD(MAP30)is a type I ribosome-inactivating protein(RIP)with antibacterial,anti-HIV and antitumor activities but lacks the ability to target tumor cells.To increase its tumor-targeting ability,the arginine-glycine-aspartic(RGD)peptide and the epidermal growth factor receptor interference(EGFRi)peptide were fused with MAP30,which was named ELRL-MAP30.The efficiency of targeted therapy for triple-negative breast cancer(TNBC)MDA-MB-231 cells,which lack the expression of estrogen receptor(ER),Progesterone receptor(PgR)and human epidermal growth factor receptor-2(HER2),is limited.In this study,we focus on exploring the effect and mechanism of ELRL-MAP30 on TNBC MDA-MB-231 cells.First,we discovered that ELRL-MAP30 significantly inhibited the migration and invasion of MDA-MB-231 cells and induced MDA-MB-231 cell apoptosis.Moreover,ELRL-MAP30 treatment resulted in a significant increase in Bax expression and a decrease in Bcl-2 expression.Furthermore,ELRL-MAP30 triggered apoptosis via the Fak/EGFR/Erk and Ilk/Akt signaling pathways.In addition,recombinant ELRL-MAP30 can inhibit chicken embryonic angiogenesis,and also inhibit the tube formation ability of human umbilical vein endothelial cells(HUVECs),indicating its potential therapeutic effects on tumor angiogenesis.Collectively,these results indicate that ELRL-MAP30 has significant tumor-targeting properties in MDA-MB-231 cancer cells and reveals potential therapeutic effects on angiogenesis.These findings indicate the potential role of ELRL-MAP30 in the targeted treatment of the TNBC cell line MDA-MB-231.展开更多
Calcium phosphate nanoparticles(CaPNPs)have good biocompatibility as gene carriers;however,CaPNPs typically exhibit a low transfection efficiency.Cell penetrate peptide(TAT)can increase the uptake of nanoparticles but...Calcium phosphate nanoparticles(CaPNPs)have good biocompatibility as gene carriers;however,CaPNPs typically exhibit a low transfection efficiency.Cell penetrate peptide(TAT)can increase the uptake of nanoparticles but is limited by its non-specificity.Grafting adhesion peptide adhesion peptide on carriers can enhance their targeting.The Plekho1 gene encodes casein kinase-2 interacting protein-1(CKIP-1),which can negatively regulate osteogenic differentiation.Based on the above,we produced a Mg-CaPNPs-RGD-TAT-CKIP-1 siRNA carrier system via hydrothermal synthesis,silanization and adsorption.The effects of this carrier system on cell endocytosis and biological effects were evaluated by cell culture in vitro.The results demonstrate that CaPNPs with 7%Mg(60 nm particle size,short rod shape and good dispersion)were suitable for use as gene carriers.The carrier system boosted the endocytosis of MG63 cells and was helpful for promoting the differentiation of osteoblasts,and the dual-ligand system possessed a synergistic effect.The findings of this study show the tremendous potential of the Mg-CaPNPs-RGD-TAT-CKIP-1 siRNA carrier system for efficient delivery into cells and osteogenesis inducement.展开更多
In this study a hovel metal ion affinity ligand was immobility onto the sensor chip. Three poly-histidine peptides were used to study the interaction of tile peptides and the immobilised metal ion affinity ligand via ...In this study a hovel metal ion affinity ligand was immobility onto the sensor chip. Three poly-histidine peptides were used to study the interaction of tile peptides and the immobilised metal ion affinity ligand via biosensor system . The results obtained in this study indicate that the affinity of immobilised Ni(Ⅱ) ion affinity ligand for these peptides appear to be related to the arrangement of the histidine residues in the peptides. This study first documents the application of biosensor technique for paptide screening.展开更多
OBJECTIVE Ganoderma lucidum polysaccharide peptides(GLPP)have an anti-oxidant activity.The oxidative stress implicates in the pathogenesis of renal ischemia-reperfusion injury(RIRI).The objective of this study was to ...OBJECTIVE Ganoderma lucidum polysaccharide peptides(GLPP)have an anti-oxidant activity.The oxidative stress implicates in the pathogenesis of renal ischemia-reperfusion injury(RIRI).The objective of this study was to determine whether GLPP could attenuate RIRI via counteracting the oxidative stress.METHODS Mice subjected to uninephrectomy with the right kidney ischemia for 35 min and reperfusion for 24 hwere used to explore the protective activity of GLPP against RIRI.In GLPP-treated group,100mg·kg-1·d-1 of GLPP were intraperitoneally injected for 7dbefore the procedure.In vitro,NRK-52 Ecells subjected to hypoxia-reoxygenation(H/R)and tunicamycin were used to explore the protective effect of GLPP against oxidative stress.The mechanisms in which GLPP protected kidney from RIRI were studied using a series of physiological and molecular biological methods.RESULTS Kidneys undergone ischemia-reperfusion showed renal dysfunction and characteristic morphological changes including cellular necrosis,brush border loss,cast formation,vacuolization and tubular dilatation while these damages were significantly attenuated by GLPP treatment.The abnormal levels of MPO,MDA and SOD caused by renal ischemia-reperfusion were significantly reversed by GLPP treatment.More apoptotic cells were found in the renal ischemia-reperfusion group than the sham group whereas GLPP reduced apoptotic cells in the ischemia-reperfusion mice by21.75%(P<0.01).The GLPPs(25-1μg·mL)alleviated H/R induced cell viability loss by 20.12%(P<0.01)andΔφm dissipation by 27.3%(P<0.01)in vitro as well and its pretreatment dramatically reduced H/R and tunicamycin induced cell injury.CONCLUSION Our study found that GLPP had a protective effect on RIRI via its anti-oxidative capacity,which suggests that GLPP may be developed as a candidate drug for preventing acute kidney injury.展开更多
In order to improve the extracellular endo-1,4-β-mannosidase(MAN) activity of recombinant Pichia pastoris, optimization of signal peptides was investigated. At first, five potential signal peptides(W1, MF4 I, INU1 A,...In order to improve the extracellular endo-1,4-β-mannosidase(MAN) activity of recombinant Pichia pastoris, optimization of signal peptides was investigated. At first, five potential signal peptides(W1, MF4 I, INU1 A, αpre, HFBI) were chosen to be analyzed by Signal P 4.0, among which W1 was designed. Then, the widely used signal peptide α-factor in expression vector p GAPZαA was replaced by those five signal peptides to reconstruct five new expression vectors. MAN activity was assayed after expression vectors were transformed into Pichia pastoris. The data show that the relative efficiencies of W1, MF4 I, INU1 A, αpre, and HFBI signal peptides are 23.5%, 203.5%, 0, 79.7%, and 120.3% compared with α-factor, respectively. The further gene copy number determination by the quantitative real-time PCR reveals that the MAN activities mediated by α-factor from 1 to 6 gene copy number levels are 12.95, 43.33, 126.63, 173.53, 103.23 and 88.63 U/m L, while those mediated by MF4 I are 79.22, 133.89, 260.14, 347.5, 206.15 and 181.89 U/m L, respectively. The maximum MAN activity reached 347.5 U/m L with 4 gene copies mediated by MF4 I. These results indicate that replacing the signal peptide α-factor with MF4 I and increasing MAN gene copies to a proper number can greatly improve the secretory expression of MAN.展开更多
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 vi...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.展开更多
This study was conducted to investigate the effect of Soybean Peptides(SPs) on ruminal fermentation and microbial diversity in vitro. Four levels of SPs supplements(0, 0.25%, 0.50% and 0.75% dry matter basis) were tes...This study was conducted to investigate the effect of Soybean Peptides(SPs) on ruminal fermentation and microbial diversity in vitro. Four levels of SPs supplements(0, 0.25%, 0.50% and 0.75% dry matter basis) were tested. p H, NH3-N, Neutral Detergent Fiber(NDF), Acid Detergent Fiber(ADF), Dry Matter Digestibility(DMD) and the Total Volatile Fatty Acid(TVFA) were measured at 6, 24, 48 h of in vitro mixed incubation the fluids. Microbial populations were determined at 24 h and Microbial Proteins(MCP) were determined at 24 and 48 h. The gas production after 48 h in vitro incubation presented linear growth(p<0.05) and the highest content was the level of 0.5% SPs(dry matter basis). NH3-N concentration reached the highest concentration with 0.75%(dry matter basis) at 48 h. p H linearly increased(linear, p<0.05) from 6 to 48 h. The digestion of DMD increased with increasing doses of SPs at 24 h. NDF and ADF linearly(p<0.01) decreased by adding SPs. The concentration of TVFA linearly increased(p<0.05) at 6, 24 and 48 h, and reached the highest concentration at the level of 0.75%(dry matter basis). SPs decreased(p<0.05) the molar proportion of acetate and propionate, respectively at 24 and 48 h. Acetat to Propionate ratio(A/P; linear, p<0.05) increased at 48 h, and reached the greatest value at the level of 0.75%(dry matter basis) at 48 h. The populations of rumen Ruminococcus flavefaciens(R. flavefaciens), Ruminococcusalbus(R. albus), Fibrobacter succinogenes(F. succinogenes), Butyrivibrio fibrisolvens(B. fibrisolvens), Streptococcus bovis(S.bovis), Ruminobacter amylophilus(R. amylophilus) and Succinimonas amylolytica(S. amylolytica) were analyzed based on the total rumen bacterial 16 S ribosomal deoxyribonucleic acid(r DNA). The relative abundance of R. flavefaciens and R. albus increased at 24 h, but the relative abundance of F. succinogenes decreased at this time. The incubation of SPs had no effect on the abundance of S. bovis and R. amylophilus. The relative abundance of B. fibrisolvens and S. amylolytica reached the greatest value(p<0.05) at middle doses of SPs inclusion at 24 h. The value of MCPs linearly increased(p<0.05) at 24 and 48 h. These results showed that SPs could improve in vitro fermentation and nutrient digestion of feed substrates, and had the ability to modulate the ruminal fermentation pattern by regulating the composition of functional rumen microbes. Hence, SPs might be a potential feed additive applied in the diets of ruminants.展开更多
Antimicrobial peptides are widely distributed in nature,existing in organisms of plants,insects,and vertebrates.It has been approved that antimicrobial peptides have broad spectrum antimicrobial activities,and play a ...Antimicrobial peptides are widely distributed in nature,existing in organisms of plants,insects,and vertebrates.It has been approved that antimicrobial peptides have broad spectrum antimicrobial activities,and play a key modulatory role in the innate immune response and tumor inhibiting activity.Due to the special action mechanism,the antimicrobial peptides become a hot field of genetic engineering.In the present paper,the general properties,mechanism of action,application value,existing problems,the latest progress and the expression strategy were discussed.展开更多
OBJECTIVE Ganoderma lucidum polysaccharide peptide(GLPP)is a group of extract from Ganoderma lucidum with a molecular mass of approximately 5×10^5,which ratio of polysaccharide to peptide is approximately 95%/5%....OBJECTIVE Ganoderma lucidum polysaccharide peptide(GLPP)is a group of extract from Ganoderma lucidum with a molecular mass of approximately 5×10^5,which ratio of polysaccharide to peptide is approximately 95%/5%.The purpose of this study was to determine whether GLPP has therapeutic effect on Non-alcoholic fatty liver disease(NAFLD).METHODS Ob/ob mouse model and ApoC3 transgenic mouse model were used for exploring the effect of GLPP on NAFLD.Key metabolic pathways and enzymes were identified by metabolomics combining with KEGG and PIUmet analyses and key enzymes were detected by Western blotting.Hepatosteatosis models of HepG2 cells and primary hepatocytes were used to further confirm the therapeutic effect of GLPP on NAFLD.RESULTS GLPP administrated for a month alleviated hepatosteatosis,dyslipidemia,liver dysfunction and liver insulin resistance.Pathways of glycerophos⁃pholipid metabolism,fatty acid metabolism and primary bile acid biosynthesis were involved in the therapeutic effect of GLPP on NAFLD.Detection of key enzymes revealed that GLPP reversed low expression of CYP7A1,CYP8B1,FXR,SHP and high expression of FGFR4 in ob/ob mice and ApoC3 mice.Besides,GLPP inhibited fatty acid synthesis by reducing the expression of SREBP1c,FAS and ACC via a FXR-SHP dependent mechanism.Additionally,GLPP reduced the accumulation of lipid droplets and the content of TG in HepG2 cells and primary hepatocytes induced by oleic acid and palmitic acid.CONCLUSION GLPP significantly improves NAFLD via regulating bile acid synthesis dependent on FXR-SHP/FGF pathway,which finally inhibits fatty acid synthesis,indicating that GLPP might be developed as a ther⁃apeutic drug for NAFLD.展开更多
Drying technology of angiotensin converting enzyme （ACE） inhibitory peptides derived from bovine casein was investigated. No significance was observed on ACE inhibitory activity of products prepared by spay drying a...Drying technology of angiotensin converting enzyme （ACE） inhibitory peptides derived from bovine casein was investigated. No significance was observed on ACE inhibitory activity of products prepared by spay drying and freeze drying （P〉0.05）. Spay drying was the best drying process for practical industry production. The inlet temperature ranged from 140℃ to 160℃ and the exit temperature ranged from 70 ℃ to 90 ℃ during the spay drying process. Under the optimal conditions, scale-up of angiotensin converted enzyme inhibitory peptide from 1 L to 10 L and the experiment was successively conducted. Peptide yield was 29% and half inhibitory concentration （IC50） was 0.53 g. L^-1.展开更多
Our previous investigation found that exendin-4 （Ex-4） , a peptide analogue of glucagon-like peptide 1 （GLP-1） , induced bone formation probably by osteoblast activation. Nevertheless, previous investigations did ...Our previous investigation found that exendin-4 （Ex-4） , a peptide analogue of glucagon-like peptide 1 （GLP-1） , induced bone formation probably by osteoblast activation. Nevertheless, previous investigations did not observe any expression of GLP-1 receptors in osteoblasts, indicating that the direct cell target of GLP-1 and its ana- logues might not be osteoblasts but some other types of cells yet to be identified. To elucidate the underlying mecha- nisms, we performed further investigation in the present study and found that GLP-1 receptor was only identified in bone marrow mesenchymal stem cells （BMSCs）. Furthermore, activation of GLP-1 receptor by Ex-4 promoted the differentiation of B MSCs into osteoblast, which was associated with activation of PKA, nuclear translocation of [5- catenin, activation of PI3K/AKT and inhibition of GSK3β. Ex-4 also inhibited the adipocyte differentiation of BM- SCs, as evidenced by inhibition of PPARγ, lipoprotein lipase expression and lipid production. Blockade of GLP-1 receptor, PKA, PI3K or Wnt pathway, or respective knock-down of GLP-1 receptor and β-catenin in BMSCs inhib- ited the Ex-4 mediated effects. The results indicated that the GLP-1 receptor mediated osteoblastic differentiation and bone formation through stimulation of PKA/β-catenin signaling and inhibition of PKA/PI3IC/AKT/GSK3β？ signaling pathway in BMSCs. The findings reveal a new role of GLP-1 receptor for regulating osteoblastic differentia- tion of B MSCs and may provide a molecular basis for novel anabolic therapeutics against osteoporosis.展开更多
As a strategy for phytopathogen control throughtransgenic way,antimicrobial peptide genes havebeen employed over the last two decades.CEMA is a cationic antimicrobial chimericpeptide,which is produced by fusing eighta...As a strategy for phytopathogen control throughtransgenic way,antimicrobial peptide genes havebeen employed over the last two decades.CEMA is a cationic antimicrobial chimericpeptide,which is produced by fusing eightamino acid residues from the antimicrobialpeptide ceropin A with a modified meltin.Threetransgenic cotton plants were generated展开更多
OBJECTIVE Metrnl is a novel secreted protein with limited researches.In this study,we investigated metrnl tissue expression pattern in humans,and exploredthe possible role of its highest expression using animal models...OBJECTIVE Metrnl is a novel secreted protein with limited researches.In this study,we investigated metrnl tissue expression pattern in humans,and exploredthe possible role of its highest expression using animal models.METHODS We examined metrnl tissue expression pattern in a human tissue microarray containing 19types of tissues from 69 donors,and verified the highest expression in fresh human and mouse tissues.We then created an animal model of cell-specific knockout mice to study the role of metrnl.RESULTS Metrnl was the highest expressed in human gastrointestinal tract,and specifical y expressed in the intestinal epithelium.Consistently,Metrnl expression was also the highest expressed in mouse gastrointestinal tract among the detected tissues of 14 types.We developed intestinal epithelial cellspecific metrnl knockout mice with Vil in-Cre.In this animal model,metrnl levels displayed a statistically significant reduction in gut fluid,but not in blood serum.This cell specific deletion of metrnl did not affect body weight,food intake,blood glucose,colon length and histology,intestinal permeability,mucus production and mucin 2 expression under physiological conditions,but markedly reduced the expression of antimicrobial peptides,such as regenerating islet-derived 3 gamma and lactotransferrin.CONCLUSION Metrnl is rich in intestinal epithelial cells of humans and mice,mainly contributing to local gut metrnl level,and less affecting systemic circulating metrnl level.Metrnl plays a role in maintaining gut antimicrobial peptides.展开更多
In recent years,studies have shown that there is a correlation between sleep disorders and cancer,but at the present stage,the research on sleep disorders and tumor related animal models is relatively insufficient.Our...In recent years,studies have shown that there is a correlation between sleep disorders and cancer,but at the present stage,the research on sleep disorders and tumor related animal models is relatively insufficient.Our research will focus on mice bearing B16F10-luc-G5 melanoma tumor with sleep fragmentation,detecting promoting effect of sleep fragmentation(SF)on the metastasis of melanoma.At the same time,we used Ganoderma lucidum poly⁃saccharides peptide(GL-pp,80 mg·kg-1),a component of traditional Chinese medicine Ganoderma lucidum,which has long enjoyed a good reputation at home and abroad,to observe its anti-tumor metastasis effects on B16F10-luc-G5 mice with SF.Then we used whole proteomics to analyze the difference proteins expressed in lung tissue and compared between groups,includes mice bearing B16F10-luc-G5,mice bearing B16F10-luc-G5 with SF and GL-pp administered mice bearing B16F10-luc-G5 with SF.With the analysis using bioinformatics,we found several key proteins,their genes name are Adcy9,ptk2,Yap1 and Lpin2,Per1 and Tim.And several important clusters,they are,immune system,platelet aggres⁃sion,energy metabolism,cell cytoskeleton,cell adhesion and circadian rhythms.Moreover,we detected the TLR4 signal pathway and macrophage differentiation to reconfirm the results of proteomics and trying to elucidate the mechanism of SF on tumor growth and metastasis and the effects of GL-pp.展开更多
OBJECTIVE Palythoa caribaeorum(class Anthozoa) is a zoanthid that together jellyfishes,hydra,and sea anemones,which are venomous and predatory,belongs to the Phyllum Cnidaria.The distinguished feature in these marine ...OBJECTIVE Palythoa caribaeorum(class Anthozoa) is a zoanthid that together jellyfishes,hydra,and sea anemones,which are venomous and predatory,belongs to the Phyllum Cnidaria.The distinguished feature in these marine animals is the cnidocytes in the body tissues,responsible for toxin production and injection that are used majorly for prey capture and defense.With exception for other anthozoans,the toxin cocktails of zoanthids have been scarcely studied and are poorly known.METHODS Based on the analysis of P.caribaeorum transcriptome,numerous predicted venom-featured polypeptides were identified,including allergens,neuro-toxins,membrane-active and Kunitz-like peptides(PcKuz).The three predicted PcKuz isotoxins(1 to 3) were selected for functional studies.Through computational processing comprising structural phylogenetic analysis,molecular docking,and dynamics simulation,PcKuz3 was shown to be a potential voltage gated potassium-channel inhibitor.RESULTS PcKuz3 fitted well as new functional Kunitz-type toxins with strong anti-locomotor activity as in vivo assessed in zebrafish larvae,with weak inhibitory effect toward proteases,as evaluated in vitro.Notably,PcKuz3 can suppress,at low concentration,the 6-OHDA-induced neurotoxicity on the locomotive behavior of zebrafish,which indicated PcKuz3 may have a neuroprotective effect.CONCLUSION Taken together,PcK uz3 figures as a novel neurotoxin structure which differs from known homologous peptides expressed in sea anemone.Moreover,the novel PcKuz3 provides an insightful hint for bio-drug development for prospective neurodegenerative disease treatment.展开更多
The aim of this study was to investigate the effect of duodenal infusion of soybean small peptides(SSP) on mammary uptake of amino acids(AA).Eight Chinese Saanen goats with duodenal fistulae and catheters were used in...The aim of this study was to investigate the effect of duodenal infusion of soybean small peptides(SSP) on mammary uptake of amino acids(AA).Eight Chinese Saanen goats with duodenal fistulae and catheters were used in a crossover design trial.Goats were infused with 0,60,120,180 g/d SSP.The experimental period lasted for 14 d.The results showed:1) milk protein yield and content were increased,with the increment in milk protein yield being significant(P【0.05).Milk fat yield and content were decreased with the increased amount of SSP infused(P【0.05).2) Mammary plasma flow was not changed(P】0.05) by SSP infusion though the average was slightly higher.Mammary plasma flow/milk yield was decreased by SSP infusion and there was significant difference between the 120 g/d treatment and the control(P【0.05).3) Compared with the control treatment,uptakes of most free amino acids were increased in the 60 and 120 g/d treatments,but decreased by the 180 g/d treatment.The uptakes of all peptide-bound essential amino acids(PB-EAA) were increased except for PB-Ile.Uptake of PB-Val,PB-Leu, PB-Phe,PB-Thr,PB-Met and PB-Lys was highest in the 120 g/d treatment.Among the peptide-bound nonessential amino acids(PB-NEAA),uptake of PB-Ser,PB-Tyr,and PB-Pro was increased(P【0.05) while that of PB-Gly was decreased(P】0.05).4) With the exception of Lys,secretion of all essential AA(EAA) was increased by SSP infusion from 0-120 g/d(P【0.05),while in the 180 g/d treatment the increase was not significant and was lower than that in the 120 g/d treatment.5) The expression of APN was increased by SSP;in the 60,120,180 g/d treatments expression was 13.55-,18.69-,and 10.01-fold over that of the controls.Conclusion:SSP might be used as substrates for milk protein synthesis by mammary gland,and can increase synthesis and secretion of milk protein.There was reason to believe that uptake and use of AA was either saturated or inhibited at high levels of infusion of SSP.Increased APN expression with infusion of SSP related to mammary uptake of PBAA by mammary gland,which suggested that APN was one of the peptidases regulating use of AA from small peptides in mammary tissue.展开更多
OBJECTIVE To identify the mechanisms by which the formyl peptide receptor 2(FPR2)mediates both inflammatory and anti-inflammatory signaling in an agonist-dependent manner.METHODS Cells expressing FPR2 were incubated w...OBJECTIVE To identify the mechanisms by which the formyl peptide receptor 2(FPR2)mediates both inflammatory and anti-inflammatory signaling in an agonist-dependent manner.METHODS Cells expressing FPR2 were incubated with weak agonists,Aβ42 and Ac2-26,before stimulation with a strong agonist,WKYMVm.Calcium mobilization,c AMP inhibition and MAP kinase activation were measured.Intramolecular FRET were determined using FPR2 constructs with an ECFP attached to the C-terminus and a Fl As H binding motif embedded in the first or third intracellular loop(IL1 or IL3,respectively).RESULTS Aβ42 did not induce significant Ca^(2+) mobilization,but positively modulated WKYMVm-induced Ca^(2+) mobilization and c AMP reduction in a dose-variable manner within a narrow range of ligand concentrations.Treating FPR2-expressing cells with Ac2-26,a peptide with anti-inflammatory activity,negatively modulated WKYMVm-induced Ca^(2+) mobilization and c AMP reduction.Intramolecular FRET assay showed that stimulation of the receptor constructs with Aβ42 brought the C-terminal domain closer to IL1 but away from IL3.An opposite conformational change was induced by Ac2-26.The FPR2 conformation induced by Aβ42 corresponded to enhanced ERK phosphorylation and attenuated p38 MAPK phosphorylation,whereas Ac2-26 induced FPR2 conformational change corresponding to elevated p38 MAPK phosphorylation and reduced ERK phosphorylation.CONCLUSION Aβ42 and Ac2-26 induce different conformational changes in FPR2.These findings provide a structural basis for FPR2 mediation of inflammatory vs anti-inflammatory functions and identify a type of receptor modulation that differs from the classic positive and negative allosteric modulation.展开更多
This purpose was to evaluate the efficacy of soybean active peptides (SAP) in 14-day old early weaned piglets feed. Eighteen crossbreed piglets Duroc ×Landrace ×Yorkshire (14-day old) were randomly divided i...This purpose was to evaluate the efficacy of soybean active peptides (SAP) in 14-day old early weaned piglets feed. Eighteen crossbreed piglets Duroc ×Landrace ×Yorkshire (14-day old) were randomly divided into three groups with six piglets each group. Control was fed with 8% animal plasma (AP). Trial 1 was fed with 4.9% AP and 4.9% SAP. Trial 2 was fed with 12.62% SAP. This raising period was 30 days and divided into three periods with earlier period (0-15 days), latter period (16-30 days) and whole period (0-30 days). The results showed that average daily gains (ADG) in trial 1 were increased 16.33%, 12.64% and 13.94% (P >0.05) and Efficiency of feed conversions (EFC) improved 17.35%, 11.40% and 13.46% than control in respective periods; ADG in trial 2 were reduced 12.24%, increased 4.21% and reduced 0.40% (P>0.05) and EFC were improved 19.81%, 13.08% and 15.76% than control in respective periods. Means of TG and LDL-C/ HDL-C in trial 1 were lowest in three groups and reduced 6.54% (P >0.05) and 0.96% than control. Means of TG, TC, LDL-C, HDL-C, LDL-C/ HDL-C were the highest in trial 2 among three groups and increased 8.93% (P >0.05), 39.69% (P <0.05), 34.94% (P >0.05), 27.31% (P >0.05) and 5.96% than control respectively. It was concluded that substituting part Ap for SAP in 14-day old piglets Feed was practicable.展开更多
文摘Momordica antiviral protein 30 kD(MAP30)is a type I ribosome-inactivating protein(RIP)with antibacterial,anti-HIV and antitumor activities but lacks the ability to target tumor cells.To increase its tumor-targeting ability,the arginine-glycine-aspartic(RGD)peptide and the epidermal growth factor receptor interference(EGFRi)peptide were fused with MAP30,which was named ELRL-MAP30.The efficiency of targeted therapy for triple-negative breast cancer(TNBC)MDA-MB-231 cells,which lack the expression of estrogen receptor(ER),Progesterone receptor(PgR)and human epidermal growth factor receptor-2(HER2),is limited.In this study,we focus on exploring the effect and mechanism of ELRL-MAP30 on TNBC MDA-MB-231 cells.First,we discovered that ELRL-MAP30 significantly inhibited the migration and invasion of MDA-MB-231 cells and induced MDA-MB-231 cell apoptosis.Moreover,ELRL-MAP30 treatment resulted in a significant increase in Bax expression and a decrease in Bcl-2 expression.Furthermore,ELRL-MAP30 triggered apoptosis via the Fak/EGFR/Erk and Ilk/Akt signaling pathways.In addition,recombinant ELRL-MAP30 can inhibit chicken embryonic angiogenesis,and also inhibit the tube formation ability of human umbilical vein endothelial cells(HUVECs),indicating its potential therapeutic effects on tumor angiogenesis.Collectively,these results indicate that ELRL-MAP30 has significant tumor-targeting properties in MDA-MB-231 cancer cells and reveals potential therapeutic effects on angiogenesis.These findings indicate the potential role of ELRL-MAP30 in the targeted treatment of the TNBC cell line MDA-MB-231.
基金Project(81571021)supported by the National Natural Science Foundation of ChinaProject(2018zzts944)supported by the Graduate Student Independent Exploration Innovation Fund of the Central South University,China+1 种基金Projects(2015WK3012,2018SK2017)supported by the Hunan Provincial Science and Technology Department,ChinaProject(20160301)supported by New Talent Project of the Third Xiangya Hospital of Central South University,China。
文摘Calcium phosphate nanoparticles(CaPNPs)have good biocompatibility as gene carriers;however,CaPNPs typically exhibit a low transfection efficiency.Cell penetrate peptide(TAT)can increase the uptake of nanoparticles but is limited by its non-specificity.Grafting adhesion peptide adhesion peptide on carriers can enhance their targeting.The Plekho1 gene encodes casein kinase-2 interacting protein-1(CKIP-1),which can negatively regulate osteogenic differentiation.Based on the above,we produced a Mg-CaPNPs-RGD-TAT-CKIP-1 siRNA carrier system via hydrothermal synthesis,silanization and adsorption.The effects of this carrier system on cell endocytosis and biological effects were evaluated by cell culture in vitro.The results demonstrate that CaPNPs with 7%Mg(60 nm particle size,short rod shape and good dispersion)were suitable for use as gene carriers.The carrier system boosted the endocytosis of MG63 cells and was helpful for promoting the differentiation of osteoblasts,and the dual-ligand system possessed a synergistic effect.The findings of this study show the tremendous potential of the Mg-CaPNPs-RGD-TAT-CKIP-1 siRNA carrier system for efficient delivery into cells and osteogenesis inducement.
文摘In this study a hovel metal ion affinity ligand was immobility onto the sensor chip. Three poly-histidine peptides were used to study the interaction of tile peptides and the immobilised metal ion affinity ligand via biosensor system . The results obtained in this study indicate that the affinity of immobilised Ni(Ⅱ) ion affinity ligand for these peptides appear to be related to the arrangement of the histidine residues in the peptides. This study first documents the application of biosensor technique for paptide screening.
基金The project supported by National Natural Science Foundation of China(81330074,81261160507,81170632,81370783,41376166)the 111Project,and International Science&Technology Cooperation Program of China 2012DFA11070
文摘OBJECTIVE Ganoderma lucidum polysaccharide peptides(GLPP)have an anti-oxidant activity.The oxidative stress implicates in the pathogenesis of renal ischemia-reperfusion injury(RIRI).The objective of this study was to determine whether GLPP could attenuate RIRI via counteracting the oxidative stress.METHODS Mice subjected to uninephrectomy with the right kidney ischemia for 35 min and reperfusion for 24 hwere used to explore the protective activity of GLPP against RIRI.In GLPP-treated group,100mg·kg-1·d-1 of GLPP were intraperitoneally injected for 7dbefore the procedure.In vitro,NRK-52 Ecells subjected to hypoxia-reoxygenation(H/R)and tunicamycin were used to explore the protective effect of GLPP against oxidative stress.The mechanisms in which GLPP protected kidney from RIRI were studied using a series of physiological and molecular biological methods.RESULTS Kidneys undergone ischemia-reperfusion showed renal dysfunction and characteristic morphological changes including cellular necrosis,brush border loss,cast formation,vacuolization and tubular dilatation while these damages were significantly attenuated by GLPP treatment.The abnormal levels of MPO,MDA and SOD caused by renal ischemia-reperfusion were significantly reversed by GLPP treatment.More apoptotic cells were found in the renal ischemia-reperfusion group than the sham group whereas GLPP reduced apoptotic cells in the ischemia-reperfusion mice by21.75%(P<0.01).The GLPPs(25-1μg·mL)alleviated H/R induced cell viability loss by 20.12%(P<0.01)andΔφm dissipation by 27.3%(P<0.01)in vitro as well and its pretreatment dramatically reduced H/R and tunicamycin induced cell injury.CONCLUSION Our study found that GLPP had a protective effect on RIRI via its anti-oxidative capacity,which suggests that GLPP may be developed as a candidate drug for preventing acute kidney injury.
基金Project(13JJ9002)supported by Hunan Provincial Natural Science Foundation of ChinaProject(2012XK4081)supported by the Key Science Technology Plan Project of Hunan Provincial Science&Technology Department,ChinaProject(CX2012B124)supported by the Graduate Degree Thesis Innovation Program of Hunan Province,China
文摘In order to improve the extracellular endo-1,4-β-mannosidase(MAN) activity of recombinant Pichia pastoris, optimization of signal peptides was investigated. At first, five potential signal peptides(W1, MF4 I, INU1 A, αpre, HFBI) were chosen to be analyzed by Signal P 4.0, among which W1 was designed. Then, the widely used signal peptide α-factor in expression vector p GAPZαA was replaced by those five signal peptides to reconstruct five new expression vectors. MAN activity was assayed after expression vectors were transformed into Pichia pastoris. The data show that the relative efficiencies of W1, MF4 I, INU1 A, αpre, and HFBI signal peptides are 23.5%, 203.5%, 0, 79.7%, and 120.3% compared with α-factor, respectively. The further gene copy number determination by the quantitative real-time PCR reveals that the MAN activities mediated by α-factor from 1 to 6 gene copy number levels are 12.95, 43.33, 126.63, 173.53, 103.23 and 88.63 U/m L, while those mediated by MF4 I are 79.22, 133.89, 260.14, 347.5, 206.15 and 181.89 U/m L, respectively. The maximum MAN activity reached 347.5 U/m L with 4 gene copies mediated by MF4 I. These results indicate that replacing the signal peptide α-factor with MF4 I and increasing MAN gene copies to a proper number can greatly improve the secretory expression of MAN.
基金supported by Medical Science and Technology Research Project of Henan Province(142102310031)
文摘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.
基金the China Agricultural Research System for providing facility and funds for experiment
文摘This study was conducted to investigate the effect of Soybean Peptides(SPs) on ruminal fermentation and microbial diversity in vitro. Four levels of SPs supplements(0, 0.25%, 0.50% and 0.75% dry matter basis) were tested. p H, NH3-N, Neutral Detergent Fiber(NDF), Acid Detergent Fiber(ADF), Dry Matter Digestibility(DMD) and the Total Volatile Fatty Acid(TVFA) were measured at 6, 24, 48 h of in vitro mixed incubation the fluids. Microbial populations were determined at 24 h and Microbial Proteins(MCP) were determined at 24 and 48 h. The gas production after 48 h in vitro incubation presented linear growth(p<0.05) and the highest content was the level of 0.5% SPs(dry matter basis). NH3-N concentration reached the highest concentration with 0.75%(dry matter basis) at 48 h. p H linearly increased(linear, p<0.05) from 6 to 48 h. The digestion of DMD increased with increasing doses of SPs at 24 h. NDF and ADF linearly(p<0.01) decreased by adding SPs. The concentration of TVFA linearly increased(p<0.05) at 6, 24 and 48 h, and reached the highest concentration at the level of 0.75%(dry matter basis). SPs decreased(p<0.05) the molar proportion of acetate and propionate, respectively at 24 and 48 h. Acetat to Propionate ratio(A/P; linear, p<0.05) increased at 48 h, and reached the greatest value at the level of 0.75%(dry matter basis) at 48 h. The populations of rumen Ruminococcus flavefaciens(R. flavefaciens), Ruminococcusalbus(R. albus), Fibrobacter succinogenes(F. succinogenes), Butyrivibrio fibrisolvens(B. fibrisolvens), Streptococcus bovis(S.bovis), Ruminobacter amylophilus(R. amylophilus) and Succinimonas amylolytica(S. amylolytica) were analyzed based on the total rumen bacterial 16 S ribosomal deoxyribonucleic acid(r DNA). The relative abundance of R. flavefaciens and R. albus increased at 24 h, but the relative abundance of F. succinogenes decreased at this time. The incubation of SPs had no effect on the abundance of S. bovis and R. amylophilus. The relative abundance of B. fibrisolvens and S. amylolytica reached the greatest value(p<0.05) at middle doses of SPs inclusion at 24 h. The value of MCPs linearly increased(p<0.05) at 24 and 48 h. These results showed that SPs could improve in vitro fermentation and nutrient digestion of feed substrates, and had the ability to modulate the ruminal fermentation pattern by regulating the composition of functional rumen microbes. Hence, SPs might be a potential feed additive applied in the diets of ruminants.
基金Supported by National 863 Project of China (2006AA10A206)
文摘Antimicrobial peptides are widely distributed in nature,existing in organisms of plants,insects,and vertebrates.It has been approved that antimicrobial peptides have broad spectrum antimicrobial activities,and play a key modulatory role in the innate immune response and tumor inhibiting activity.Due to the special action mechanism,the antimicrobial peptides become a hot field of genetic engineering.In the present paper,the general properties,mechanism of action,application value,existing problems,the latest progress and the expression strategy were discussed.
基金National Natural Science Foundation of China(8133007481620108029+1 种基金81261160507)Beijing Natural Science Foundation(7172113)
文摘OBJECTIVE Ganoderma lucidum polysaccharide peptide(GLPP)is a group of extract from Ganoderma lucidum with a molecular mass of approximately 5×10^5,which ratio of polysaccharide to peptide is approximately 95%/5%.The purpose of this study was to determine whether GLPP has therapeutic effect on Non-alcoholic fatty liver disease(NAFLD).METHODS Ob/ob mouse model and ApoC3 transgenic mouse model were used for exploring the effect of GLPP on NAFLD.Key metabolic pathways and enzymes were identified by metabolomics combining with KEGG and PIUmet analyses and key enzymes were detected by Western blotting.Hepatosteatosis models of HepG2 cells and primary hepatocytes were used to further confirm the therapeutic effect of GLPP on NAFLD.RESULTS GLPP administrated for a month alleviated hepatosteatosis,dyslipidemia,liver dysfunction and liver insulin resistance.Pathways of glycerophos⁃pholipid metabolism,fatty acid metabolism and primary bile acid biosynthesis were involved in the therapeutic effect of GLPP on NAFLD.Detection of key enzymes revealed that GLPP reversed low expression of CYP7A1,CYP8B1,FXR,SHP and high expression of FGFR4 in ob/ob mice and ApoC3 mice.Besides,GLPP inhibited fatty acid synthesis by reducing the expression of SREBP1c,FAS and ACC via a FXR-SHP dependent mechanism.Additionally,GLPP reduced the accumulation of lipid droplets and the content of TG in HepG2 cells and primary hepatocytes induced by oleic acid and palmitic acid.CONCLUSION GLPP significantly improves NAFLD via regulating bile acid synthesis dependent on FXR-SHP/FGF pathway,which finally inhibits fatty acid synthesis,indicating that GLPP might be developed as a ther⁃apeutic drug for NAFLD.
基金Supported by Scientific Research Foundation for Young Scholars of Heilongjiang Province of China (QC07C25)The National High Technology Research and Development Program of China (2008AA10Z315)
文摘Drying technology of angiotensin converting enzyme （ACE） inhibitory peptides derived from bovine casein was investigated. No significance was observed on ACE inhibitory activity of products prepared by spay drying and freeze drying （P〉0.05）. Spay drying was the best drying process for practical industry production. The inlet temperature ranged from 140℃ to 160℃ and the exit temperature ranged from 70 ℃ to 90 ℃ during the spay drying process. Under the optimal conditions, scale-up of angiotensin converted enzyme inhibitory peptide from 1 L to 10 L and the experiment was successively conducted. Peptide yield was 29% and half inhibitory concentration （IC50） was 0.53 g. L^-1.
文摘Our previous investigation found that exendin-4 （Ex-4） , a peptide analogue of glucagon-like peptide 1 （GLP-1） , induced bone formation probably by osteoblast activation. Nevertheless, previous investigations did not observe any expression of GLP-1 receptors in osteoblasts, indicating that the direct cell target of GLP-1 and its ana- logues might not be osteoblasts but some other types of cells yet to be identified. To elucidate the underlying mecha- nisms, we performed further investigation in the present study and found that GLP-1 receptor was only identified in bone marrow mesenchymal stem cells （BMSCs）. Furthermore, activation of GLP-1 receptor by Ex-4 promoted the differentiation of B MSCs into osteoblast, which was associated with activation of PKA, nuclear translocation of [5- catenin, activation of PI3K/AKT and inhibition of GSK3β. Ex-4 also inhibited the adipocyte differentiation of BM- SCs, as evidenced by inhibition of PPARγ, lipoprotein lipase expression and lipid production. Blockade of GLP-1 receptor, PKA, PI3K or Wnt pathway, or respective knock-down of GLP-1 receptor and β-catenin in BMSCs inhib- ited the Ex-4 mediated effects. The results indicated that the GLP-1 receptor mediated osteoblastic differentiation and bone formation through stimulation of PKA/β-catenin signaling and inhibition of PKA/PI3IC/AKT/GSK3β？ signaling pathway in BMSCs. The findings reveal a new role of GLP-1 receptor for regulating osteoblastic differentia- tion of B MSCs and may provide a molecular basis for novel anabolic therapeutics against osteoporosis.
文摘As a strategy for phytopathogen control throughtransgenic way,antimicrobial peptide genes havebeen employed over the last two decades.CEMA is a cationic antimicrobial chimericpeptide,which is produced by fusing eightamino acid residues from the antimicrobialpeptide ceropin A with a modified meltin.Threetransgenic cotton plants were generated
基金The project supported by National Natural Science Foundation of China(81130061,81202572,81373414)
文摘OBJECTIVE Metrnl is a novel secreted protein with limited researches.In this study,we investigated metrnl tissue expression pattern in humans,and exploredthe possible role of its highest expression using animal models.METHODS We examined metrnl tissue expression pattern in a human tissue microarray containing 19types of tissues from 69 donors,and verified the highest expression in fresh human and mouse tissues.We then created an animal model of cell-specific knockout mice to study the role of metrnl.RESULTS Metrnl was the highest expressed in human gastrointestinal tract,and specifical y expressed in the intestinal epithelium.Consistently,Metrnl expression was also the highest expressed in mouse gastrointestinal tract among the detected tissues of 14 types.We developed intestinal epithelial cellspecific metrnl knockout mice with Vil in-Cre.In this animal model,metrnl levels displayed a statistically significant reduction in gut fluid,but not in blood serum.This cell specific deletion of metrnl did not affect body weight,food intake,blood glucose,colon length and histology,intestinal permeability,mucus production and mucin 2 expression under physiological conditions,but markedly reduced the expression of antimicrobial peptides,such as regenerating islet-derived 3 gamma and lactotransferrin.CONCLUSION Metrnl is rich in intestinal epithelial cells of humans and mice,mainly contributing to local gut metrnl level,and less affecting systemic circulating metrnl level.Metrnl plays a role in maintaining gut antimicrobial peptides.
文摘In recent years,studies have shown that there is a correlation between sleep disorders and cancer,but at the present stage,the research on sleep disorders and tumor related animal models is relatively insufficient.Our research will focus on mice bearing B16F10-luc-G5 melanoma tumor with sleep fragmentation,detecting promoting effect of sleep fragmentation(SF)on the metastasis of melanoma.At the same time,we used Ganoderma lucidum poly⁃saccharides peptide(GL-pp,80 mg·kg-1),a component of traditional Chinese medicine Ganoderma lucidum,which has long enjoyed a good reputation at home and abroad,to observe its anti-tumor metastasis effects on B16F10-luc-G5 mice with SF.Then we used whole proteomics to analyze the difference proteins expressed in lung tissue and compared between groups,includes mice bearing B16F10-luc-G5,mice bearing B16F10-luc-G5 with SF and GL-pp administered mice bearing B16F10-luc-G5 with SF.With the analysis using bioinformatics,we found several key proteins,their genes name are Adcy9,ptk2,Yap1 and Lpin2,Per1 and Tim.And several important clusters,they are,immune system,platelet aggres⁃sion,energy metabolism,cell cytoskeleton,cell adhesion and circadian rhythms.Moreover,we detected the TLR4 signal pathway and macrophage differentiation to reconfirm the results of proteomics and trying to elucidate the mechanism of SF on tumor growth and metastasis and the effects of GL-pp.
基金Macao Science and Technology Development Fund(017/2015/AMJ134/2014/A3).
文摘OBJECTIVE Palythoa caribaeorum(class Anthozoa) is a zoanthid that together jellyfishes,hydra,and sea anemones,which are venomous and predatory,belongs to the Phyllum Cnidaria.The distinguished feature in these marine animals is the cnidocytes in the body tissues,responsible for toxin production and injection that are used majorly for prey capture and defense.With exception for other anthozoans,the toxin cocktails of zoanthids have been scarcely studied and are poorly known.METHODS Based on the analysis of P.caribaeorum transcriptome,numerous predicted venom-featured polypeptides were identified,including allergens,neuro-toxins,membrane-active and Kunitz-like peptides(PcKuz).The three predicted PcKuz isotoxins(1 to 3) were selected for functional studies.Through computational processing comprising structural phylogenetic analysis,molecular docking,and dynamics simulation,PcKuz3 was shown to be a potential voltage gated potassium-channel inhibitor.RESULTS PcKuz3 fitted well as new functional Kunitz-type toxins with strong anti-locomotor activity as in vivo assessed in zebrafish larvae,with weak inhibitory effect toward proteases,as evaluated in vitro.Notably,PcKuz3 can suppress,at low concentration,the 6-OHDA-induced neurotoxicity on the locomotive behavior of zebrafish,which indicated PcKuz3 may have a neuroprotective effect.CONCLUSION Taken together,PcK uz3 figures as a novel neurotoxin structure which differs from known homologous peptides expressed in sea anemone.Moreover,the novel PcKuz3 provides an insightful hint for bio-drug development for prospective neurodegenerative disease treatment.
文摘The aim of this study was to investigate the effect of duodenal infusion of soybean small peptides(SSP) on mammary uptake of amino acids(AA).Eight Chinese Saanen goats with duodenal fistulae and catheters were used in a crossover design trial.Goats were infused with 0,60,120,180 g/d SSP.The experimental period lasted for 14 d.The results showed:1) milk protein yield and content were increased,with the increment in milk protein yield being significant(P【0.05).Milk fat yield and content were decreased with the increased amount of SSP infused(P【0.05).2) Mammary plasma flow was not changed(P】0.05) by SSP infusion though the average was slightly higher.Mammary plasma flow/milk yield was decreased by SSP infusion and there was significant difference between the 120 g/d treatment and the control(P【0.05).3) Compared with the control treatment,uptakes of most free amino acids were increased in the 60 and 120 g/d treatments,but decreased by the 180 g/d treatment.The uptakes of all peptide-bound essential amino acids(PB-EAA) were increased except for PB-Ile.Uptake of PB-Val,PB-Leu, PB-Phe,PB-Thr,PB-Met and PB-Lys was highest in the 120 g/d treatment.Among the peptide-bound nonessential amino acids(PB-NEAA),uptake of PB-Ser,PB-Tyr,and PB-Pro was increased(P【0.05) while that of PB-Gly was decreased(P】0.05).4) With the exception of Lys,secretion of all essential AA(EAA) was increased by SSP infusion from 0-120 g/d(P【0.05),while in the 180 g/d treatment the increase was not significant and was lower than that in the 120 g/d treatment.5) The expression of APN was increased by SSP;in the 60,120,180 g/d treatments expression was 13.55-,18.69-,and 10.01-fold over that of the controls.Conclusion:SSP might be used as substrates for milk protein synthesis by mammary gland,and can increase synthesis and secretion of milk protein.There was reason to believe that uptake and use of AA was either saturated or inhibited at high levels of infusion of SSP.Increased APN expression with infusion of SSP related to mammary uptake of PBAA by mammary gland,which suggested that APN was one of the peptidases regulating use of AA from small peptides in mammary tissue.
基金supported by National Natural Science Foundation of China(31470856 to RDY)the Science and Technology Development Fund of Macao(FDCT 072/2015/A2)the University of Macao(SRG2015-00047-ICMS-QRCM)
文摘OBJECTIVE To identify the mechanisms by which the formyl peptide receptor 2(FPR2)mediates both inflammatory and anti-inflammatory signaling in an agonist-dependent manner.METHODS Cells expressing FPR2 were incubated with weak agonists,Aβ42 and Ac2-26,before stimulation with a strong agonist,WKYMVm.Calcium mobilization,c AMP inhibition and MAP kinase activation were measured.Intramolecular FRET were determined using FPR2 constructs with an ECFP attached to the C-terminus and a Fl As H binding motif embedded in the first or third intracellular loop(IL1 or IL3,respectively).RESULTS Aβ42 did not induce significant Ca^(2+) mobilization,but positively modulated WKYMVm-induced Ca^(2+) mobilization and c AMP reduction in a dose-variable manner within a narrow range of ligand concentrations.Treating FPR2-expressing cells with Ac2-26,a peptide with anti-inflammatory activity,negatively modulated WKYMVm-induced Ca^(2+) mobilization and c AMP reduction.Intramolecular FRET assay showed that stimulation of the receptor constructs with Aβ42 brought the C-terminal domain closer to IL1 but away from IL3.An opposite conformational change was induced by Ac2-26.The FPR2 conformation induced by Aβ42 corresponded to enhanced ERK phosphorylation and attenuated p38 MAPK phosphorylation,whereas Ac2-26 induced FPR2 conformational change corresponding to elevated p38 MAPK phosphorylation and reduced ERK phosphorylation.CONCLUSION Aβ42 and Ac2-26 induce different conformational changes in FPR2.These findings provide a structural basis for FPR2 mediation of inflammatory vs anti-inflammatory functions and identify a type of receptor modulation that differs from the classic positive and negative allosteric modulation.
文摘This purpose was to evaluate the efficacy of soybean active peptides (SAP) in 14-day old early weaned piglets feed. Eighteen crossbreed piglets Duroc ×Landrace ×Yorkshire (14-day old) were randomly divided into three groups with six piglets each group. Control was fed with 8% animal plasma (AP). Trial 1 was fed with 4.9% AP and 4.9% SAP. Trial 2 was fed with 12.62% SAP. This raising period was 30 days and divided into three periods with earlier period (0-15 days), latter period (16-30 days) and whole period (0-30 days). The results showed that average daily gains (ADG) in trial 1 were increased 16.33%, 12.64% and 13.94% (P >0.05) and Efficiency of feed conversions (EFC) improved 17.35%, 11.40% and 13.46% than control in respective periods; ADG in trial 2 were reduced 12.24%, increased 4.21% and reduced 0.40% (P>0.05) and EFC were improved 19.81%, 13.08% and 15.76% than control in respective periods. Means of TG and LDL-C/ HDL-C in trial 1 were lowest in three groups and reduced 6.54% (P >0.05) and 0.96% than control. Means of TG, TC, LDL-C, HDL-C, LDL-C/ HDL-C were the highest in trial 2 among three groups and increased 8.93% (P >0.05), 39.69% (P <0.05), 34.94% (P >0.05), 27.31% (P >0.05) and 5.96% than control respectively. It was concluded that substituting part Ap for SAP in 14-day old piglets Feed was practicable.
