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Targeted screening of an anti-inflammatory polypeptide from Rhopilema esculentum Kishinouye cnidoblasts and elucidation of its mechanism in alleviating ulcerative colitis based on an analysis of the gut microbiota and metabolites
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作者 Ziyan Wang Qiuyue Shi +5 位作者 Ying Feng Jiaojiao Han Chenyang Lu Jun Zhou Zhonghua Wang Xiurong Su 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1336-1347,共12页
Ulcerative colitis(UC)is a recurrent inflammatory bowel disease that imposes a severe burden on families and society.In recent years,exploiting the potential of marine bioactive peptides for the treatment of diseases ... Ulcerative colitis(UC)is a recurrent inflammatory bowel disease that imposes a severe burden on families and society.In recent years,exploiting the potential of marine bioactive peptides for the treatment of diseases has become a topic of intense research interest.This study revealed the mechanism underlying the protective effect of the dominant polypeptide PKKVV(Pro-Lys-Lys-Val-Val)of Rhopilema esculentum cnidoblasts against DSS-induced UC through a combined analysis of the metagenome and serum metabolome.Specifically,the polypeptide composition of R.esculentum cnidoblasts was determined by matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF/TOF-MS).Molecular docking showed that the dominant peptide PKKVV could bind better with tumor necrosis factor-α(TNF-α)than the original ligand.Subsequent animal experiments suggested that PKKVV could modulate disorganized gut microorganisms in mice with UC;affect serum metabolites through the arachidonic acid,glycerophospholipid and linoleic acid metabolism pathways;and further alleviate UC symptoms.This study provides a reference for the comprehensive development of marine bioactive substances and nonpharmaceutical treatments for UC. 展开更多
关键词 Ulcerative colitis Rhopilema esculentum Kishinouye Cnidoblasts Marine bioactive polypeptides METAGENOME Serum metabolome
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Practical guide:Glucagon-like peptide-1 and dual glucosedependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonists in diabetes mellitus
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作者 Saleh Fahad Alqifari Omar Alkomi +13 位作者 Abdullah Esmail Khadijeh Alkhawami Shahd Yousri Mohamad Ayham Muqresh Nawwarah Alharbi Abdullah A Khojah Ahmed Aljabri Abdulrahman Allahham Kousalya Prabahar Hanan Alshareef Mohammed Aldhaeefi Tariq Alrasheed Ali Alrabiah Laila A AlBishi 《World Journal of Diabetes》 SCIE 2024年第3期331-347,共17页
Practical guide:Glucagon-like peptide-1 and dual glucosedependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonists in diabetes mellitus common second-line choice after metformin for treating T2... Practical guide:Glucagon-like peptide-1 and dual glucosedependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonists in diabetes mellitus common second-line choice after metformin for treating T2DM.Various considerations can make selecting and switching between different GLP-1 RAs challenging.Our study aims to provide a comprehensive guide for the usage of GLP-1 RAs and dual GIP and GLP-1 RAs for the management of T2DM. 展开更多
关键词 Glucagon-like peptide-1 receptor agonist Diabetes mellitus Metabolic syndrome Dual glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist Clinical practice ENDOCRINOLOGY
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Achyranthes bidentata polypeptides prevent apoptosis by inhibiting the glutamate current in cultured hippocampal neurons 被引量:5
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作者 Rong-Lu Pan Wen-Qing Hu +3 位作者 Jie Pan Li Huang Cheng-Cheng Luan Hong-Mei Shen 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第6期1086-1093,共8页
Glutamate-induced excitotoxicity plays a critical role in the neurological impairment caused by middle cerebral artery occlusion.Achyranthes bidentata polypeptides have been shown to protect against neurological funct... Glutamate-induced excitotoxicity plays a critical role in the neurological impairment caused by middle cerebral artery occlusion.Achyranthes bidentata polypeptides have been shown to protect against neurological functional damage caused by middle cerebral artery occlusion,but the underlying neuroprotective mechanisms and the relationship to glutamate-induced excitotoxicity remain unclear.Therefore,in the current study,we investigated the protective effects of Achyranthes bidentata polypeptides against glutamate-induced excitotoxicity in cultured hippocampal neurons.Hippocampal neurons were treated with Mg^2+-free extracellular solution containing glutamate(300μM)for 3 hours as a model of glutamate-mediated excitotoxicity(glutamate group).In the normal group,hippocampal neurons were incubated in Mg^2+-free extracellular solution.In the Achyranthes bidentata polypeptide group,hippocampal neurons were incubated in Mg^2+-free extracellular solution containing glutamate(300μM)and Achyranthes bidentata polypeptide at different concentrations.At 24 hours after exposure to the agents,3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and Hoechst 33258 staining were used to assess neuronal viability and nuclear m'orphology,respectively.Caspase-3 expression and activity were evaluated using western blot assay and colorimetric enzymatic assay,respectively.At various time points after glutamate treatment,reactive oxygen species in cells were detected by H2 DCF-DA,and mitochondrial membrane potential was detected by rhodamine 123 staining.To examine the effect of Achyranthes bidentata polypeptides on glutamate receptors,electrophysiological recording was used to measure the glutamate-induced inward current in cultured hippocampal neurons.Achyranthes bidentata polypeptide decreased the percentage of apoptotic cells and reduced the changes in caspase-3 expression and activity induced by glutamate.In addition,Achyranthes bidentata polypeptide attenuated the amplitude of the glutamate-induced current.Furthermore,the glutamate-induced increase in intracellular reactive oxygen species and reduction in mitochondrial membrane potential were attenuated by Achyranthes bidentata polypeptide treatment.These findings collectively suggest that Achyranthes bidentata polypeptides exert a neuroprotective effect in cultured hippocampal neurons by suppressing the overactivation of glutamate receptors and inhibiting the caspase-3-dependent mitochondrial apoptotic pathway.All animal studies were approved by the Animal Care and Use Committee,Nantong University,China(approval No.20120216-001)on February 16,2012. 展开更多
关键词 Achyranthes bidentata polypeptides APOPTOSIS caspase-3 EXCITOTOXICITY GLUTAMATE receptors MITOCHONDRIAL dysfunction MITOCHONDRIAL membrane potential neuroprotection reactive oxygen species STAUROSPORINE
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SURFACE MODIFICATION OF POLYPROPYLENE MICROPOROUS MEMBRANE BY TETHERING POLYPEPTIDES 被引量:3
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作者 徐志康 Mathias Ulbricht 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第5期529-538,共10页
Two kinds of polypeptides were tethered onto the surface of polypropylene microporous membrane (PPMM) through a ring opening polymerization of L-glutamate N-carboxyanhydride initiated by amino groups which were intr... Two kinds of polypeptides were tethered onto the surface of polypropylene microporous membrane (PPMM) through a ring opening polymerization of L-glutamate N-carboxyanhydride initiated by amino groups which were introduced by ammonia plasma and y-aminopropyl triethanoxysilane treatments. X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared spectroscopy (FT-IR/ATR), scanning electron microscopy (SEM), together with water contact angle measurements were used to characterize the modified membranes. XPS analyses and FT-IR/ATR spectra demonstrated that polypeptides are actually grafted onto the membrane surface. The wettability of the membrane surface increases at first and then decreases with the increase in grafting degrees of polypeptide. Platelet adhesion and murine macrophage attachment experiments reveal an enhanced hemocompatibility for the polypeptide modified PPMMs. All these results give evidence that polypeptide grafting can simultaneously improve the hemocompatibility as well as reserve the hydrophobicity for the membrane, which will provide a potential approach to improve the performance of polypropylene hollow fiber microporous membrane used in artificial oxygenator. 展开更多
关键词 Polypropylene microporous membrane Graft polymerization polypeptidE Surface modification Biocompatibility.
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Synthesis and Cleavage Activity of Artifical Minic Polypeptides 被引量:2
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作者 Yong YE Xiao Lian HU +3 位作者 Ping LI Ming Yu NIU Li Feng CAO Yu Fen ZHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第9期1197-1200,共4页
Two artificial minic polypeptides which are synthetic analogues of natural products with DNA affinity were synthesized, and theirs cleavage activity with DNA were examined. The structures of these compounds was confir... Two artificial minic polypeptides which are synthetic analogues of natural products with DNA affinity were synthesized, and theirs cleavage activity with DNA were examined. The structures of these compounds was confirmed by ^1H NMR, MS and IR. 展开更多
关键词 DNA artificial minic polypeptide cleavage agents.
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Facile Preparation of Polypeptides:Moisture Insensitive and Superfast Ring Opening Polymerization of N-Carboxyanhydrides 被引量:3
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作者 栾世方 《材料导报》 EI CAS CSCD 北大核心 2019年第1期1-2,共2页
(a)NCA polymerization initiated by LiHMDS or other initiators in THF,initiator i)n-hexylamine,ii)HMDS,iii)bipyNi(COD);(b)LiHMDS-initiated open vessel polymerization of BLGNCA at 26 mg and 2 g scale;(c)GPC traces of po... (a)NCA polymerization initiated by LiHMDS or other initiators in THF,initiator i)n-hexylamine,ii)HMDS,iii)bipyNi(COD);(b)LiHMDS-initiated open vessel polymerization of BLGNCA at 26 mg and 2 g scale;(c)GPC traces of poly-BLG at variable DP;(d)Reaction rates of LiHMDS and hexylamine initiated BLGNCA polymerization in THF with NCA:initiator ratio of 100∶1 and initial NCA concentration at 0.2 mol/L;(e)CD spectra of poly-BLG at variable DP prepared from LiHMDS-initiated NCA polymerization. 展开更多
关键词 FACILE PREPARATION polypeptides:moisture insensitive
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Construction of Expressing Plasmids of Recombinant FN Polypeptides with Bifunctional-domain and the Characterization of the P 被引量:1
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作者 冯作化 张桂梅 +1 位作者 李东 张慧 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1996年第2期70-74,86,共6页
Two expressing plasmids have been constructed and used to express two bifunctional-domain recombinant polypeptides of human fibronectin (FN) in E. coli. One was CH50 (Pro1239-Ser1515 of FN linked with Ala1690-Thr1960 ... Two expressing plasmids have been constructed and used to express two bifunctional-domain recombinant polypeptides of human fibronectin (FN) in E. coli. One was CH50 (Pro1239-Ser1515 of FN linked with Ala1690-Thr1960 of FN through Met) and the other was CH56 (Pro1239-Thr1960 of FN). Both of two polypeptides were capable of binding heparin and were purified by heparin-a-garose affinity chromatography. The purified products were capable of binding cells. The production of CH50 and CH56 polypeptides provided a fundamental basis for further study of the anti-metastatic function of recombinant fibronectin polypeptides. 展开更多
关键词 FIBRONECTIN recombinant polypeptide metastasis
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State of arts on the bio-synthesis of noble metal nanoparticles and their biological application 被引量:2
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作者 Kok Bing Tan Daohua Sun +2 位作者 Jiale Huang Tareque Odoom-Wubah Qingbiao Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第2期272-290,共19页
Nanomaterials are materials in which at least one of the dimensions of the particles is 100 nm and below.There are many types of nanomaterials,but noble metal nanoparticles are of interest due to their uniquely large ... Nanomaterials are materials in which at least one of the dimensions of the particles is 100 nm and below.There are many types of nanomaterials,but noble metal nanoparticles are of interest due to their uniquely large surface-to-volume ratio,high surface area,optical and electronic properties,high stability,easy synthesis,and tunable surface functionalization.More importantly,noble metal nanoparticles are known to have excellent compatibility with bio-materials,which is why they are widely used in biological applications.The synthesis method of noble metal nanoparticles conventionally involves the reduction of the noble metal salt precursor by toxic reaction agents such as NaBH4,hydrazine,and formaldehyde.This is a major drawback for researchers involved in biological application researches.Hence,the bio-synthesis of noble metal nanoparticles(NPs)by bio-materials via bio-reduction provides an alternative method to synthesize noble metal nanoparticles which are potentially non-toxic and safer for biological application.In this review,the bio-synthesis of noble metal nanoparticle including gold nanoparticle(AuNPs),silver nanoparticle(AgNPs),platinum nanoparticle(PtNPs),and palladium nanoparticle(PdNPs)are first discussed.This is followed by a discussion of these biosynthesized noble metal in biological applications including antimicrobial,wound healing,anticancer drug,and bioimaging.Based on these,it can be concluded that the study on bio-synthesized noble metal nanoparticles will expand further involving bio-reduction by unexplored bio-materials.However,many questions remain on the feasibility of bio-synthesized noble metal nanoparticles to replace existing methods on various biological applications.Nevertheless,the current development of the biological application by bio-synthesized noble metal NPs is still intensively ongoing,and will eventually reach the goal of full commercialization. 展开更多
关键词 Noble metal nanoparticles bio-synthesis Bio-templating Bio-material Bio-logical application NANOMATERIALS
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Structure Characterization of Silk Fibroin Crystalline Domain Polypeptides Expressed in Escherichia coli 被引量:1
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作者 王建南 闫书芹 白伦 《Journal of Donghua University(English Edition)》 EI CAS 2011年第1期1-4,共4页
The molecular conformations of four silk fibroin crystalline analogues [GAGAG-X] 16(G,Gly;A,Ala;X=Ala,Ser,Tyr or Val,designated eGA,eGS,eGY or eGV),carried out using molecular design and expressed by Escherichia coil(... The molecular conformations of four silk fibroin crystalline analogues [GAGAG-X] 16(G,Gly;A,Ala;X=Ala,Ser,Tyr or Val,designated eGA,eGS,eGY or eGV),carried out using molecular design and expressed by Escherichia coil(E.coli),were evaluated by Raman spectra analysis.The abilities of forming β-sheet structure were determined by thioflavin T(ThT) fluorescence spectra analysis.In terms of molecular conformation,except eGY that could not form significant typical molecular conformation,eGS and eGV were mainly composed of β-sheets while eGA tended to form β-turn.β-turn was also present in eGY and absent in eGS and eGV.In terms of β-sheet structure,eGS had the highest β-sheet content,followed by eGV,and eGA had the lowest content,furthermore,β-sheet structures were more stable in eGS and eGV than those in eGA and eGY. 展开更多
关键词 fibroin crystalline combination polypeptide Β-SHEET thioflavin T(ThT) Raman spectra
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DEFENSE MECHANISMS OF URINARY BLADDER:STUDIES ON ANTIMICROBIAL POLYPEPTIDES FROM BLADDER MUCOSA 被引量:1
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作者 吴琦 王伯瑶 《Chinese Medical Sciences Journal》 CAS CSCD 1999年第1期17-22,共6页
INTRODUCTIONTheinherentresistanceofthenormalurinaryblad-dertoinfectionshasbeenrecognizedforoveracentury(1).B... INTRODUCTIONTheinherentresistanceofthenormalurinaryblad-dertoinfectionshasbeenrecognizedforoveracentury(1).Beginninginthe1960... 展开更多
关键词 多肽类 抗菌素 膀胱粘膜 动物试验 缩氨酸
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Therapeutic effects of velvet antler polypeptides on hepatic fibrosis in rats
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作者 Leng-xinDUAN Cai-eWANG +2 位作者 Ji-leXIN Yi-mengDUAN Jian-gangWANG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2015年第S1期56-57,共2页
OBJECTIVE To explore the therapeutic effects and underlying mechanisms of velvet antler polypeptides(VVAPs)in CCl4-induced experimental hepatic fibrosis in rats.METHODS Anti-hepatic fibrosis properties of VAPs were te... OBJECTIVE To explore the therapeutic effects and underlying mechanisms of velvet antler polypeptides(VVAPs)in CCl4-induced experimental hepatic fibrosis in rats.METHODS Anti-hepatic fibrosis properties of VAPs were tested by Subcutaneous injection(SC)into male Wistar rats of CCl4- induced experimental hepatic fibrosis.After SC injections for 45 consecutive days at doses of 5mg·kg-1(low dose,VAPsL),10mg·kg-1(mid-dose,VAPsM)and 20mg·kg-1(high-dose,VAPsH),the rats were sacrificed and the various indicators were evaluated and tested.Observed hepatic cells degeneration and necrosis,inflammatory infiltration and levels of serum enzymes to assess treatment of VAPs;The expression levels of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),MDA,and hydroxyproline(HYP)in liver tissue were analyzed;RT-PCR analysis was carried out to detect the expression levels of matrix metalloproteinases2(MMP-2)and tissue inhibitor of metalloproteinases 1(TIMP-1)in liver tissue.RESULTS VAPs has obvious anti-hepatic fibrosis effects.Hepatocyte swelling,fatty degeneration was significantly reduced,reducing infiltration of inflammatory cells.Release of alanine aminotransferase(ALT)and aspartate aminotransferase(AST)decreased significantly,reduction of hyaluronic acid(HA)and laminin(LN)obviously,at the same time,the content of total protein and albumin increased significantly in serum.Activity of SOD and GSH-Px was significantly raised and the content of MDA and HYP was reduced significantly in liver tissue.Expression levels of MMP-2and TIMP-1 mRNA in liver were decreased significantly.These improvements were more significant in high-dos and mid-dose groups(P<0.05 or P<0.01 vs model group).CONCLUSION These findings suggest VAPs can significant treat the hepatic fibrosis,which may be due to protect liver cells and improve liver functions by hydroxyl radical scavenging activity and great effect of antioxidation,and decrease the gene expression of MMP-2,improving exist-environment of liver cells and decreasing the gene expression of TIMP-1,prompting degradation of extracellular matrix. 展开更多
关键词 VELVET ANTLER polypeptidE HEPATIC FIBROSIS oxidati
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Protective effects of Achyranthes bidentata polypeptides on retinal ganglion cells post-optic nerve crush in rats
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作者 Nan Hu Qi Zhao +2 位作者 Fangling Zhang Junfang Zhang Xiaosong Gu 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第15期1164-1168,共5页
Achyranthes bidentata polypeptides(ABPP) have been reported to inhibit apoptosis of retinal ganglion cells(RGCs).The present study investigated the protective effects of ABPP on RGCs in a rat model of optic nerve ... Achyranthes bidentata polypeptides(ABPP) have been reported to inhibit apoptosis of retinal ganglion cells(RGCs).The present study investigated the protective effects of ABPP on RGCs in a rat model of optic nerve injury.With prolonged injury time,RGC densities were gradually decreased.ABPP(5 μg) significantly increased RGC densities and upregulated growth associated protein 43 expression in rats with optic nerve injury.Results demonstrate that ABPP can protect RGCs and promote axonal growth after optic nerve crush. 展开更多
关键词 Achyranthes bidentata polypeptides optic nerve crush retinal ganglion cells growth associated protein 43 neural regeneration
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Force-Regulated Adhesion and Activation Study of Integrin Targeting Polypeptides
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作者 Ke Ding Zhengjiao Cao +2 位作者 Quan Long Ting Xiong Botao Xiao 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期155-155,共1页
Integrins are heterodimeric cell surface receptors that bind to ligands on another cell,e.g.intercellular adhesion molecule 1(ICAM-1),or the extracellular matrix.Integrins play an important role in immune system,and t... Integrins are heterodimeric cell surface receptors that bind to ligands on another cell,e.g.intercellular adhesion molecule 1(ICAM-1),or the extracellular matrix.Integrins play an important role in immune system,and they participate in inflammation,thrombosis,and proliferation,migration and apoptosis of tumor cells.They mediate adhesion and transduce signals across the membrane usually under the influence of forces.A recent study has shown that integrins bind and activate transforming growth factorβisoform(TGF-β)which is involved in tumor suppression and growth,and blocking the binding of TGF-βto integrin can inhibit tumor growth.RGD(arginine-glycine-aspartate)small peptide,which competitively inhibits ligand binding to integrins,has been approved as an injectable drug.However,when the RGD is used to block cancer-related extracellular signaling pathways,it will also cause activation of integrins for a period,and stimulate the transduction of intracellular signals constantly.Therefore,it is necessary to explore for new drugs that can selectively control conformational state of integrins without activating or blocking all of them.In this study,we selected two small peptides,KQAGDV and RTDLDSLRT,that combined with integrins and do not contain an RGD sequence.The non-RGD polypeptide RTDLDSLRT has been reported to have a binding site with integrins and the binding affinity is on nanomolar scale.For the motif of the fibrinogen y chain C-terminal KQAGDV,it can adhere to the head of the integrins.The micropipette aspiration technique and electron microscopy techniques were used to study the adhesion and activation of integrins by peptides,respectively.Micropipette aspiration technique was used to investigate the adhesion frequency of peptide and integrin on Jurkat cell.The pressure system was used to supply a controllable negative pression to the microtube,and two micropipettes were used to absorb red blood cells and Jurkat cells,respectively.The red blood cells were coated with small peptides and can serve as a force sensor after being sucked when two cells were connected.The binding kinetics of integrin and peptides interactions was determined by fitting the curves constructed using adhesion probability between two cells as a function of time.The curves were fitted using a small system probabilistic kinetic model to estimate a pair of kinetic parameters,including the zero force reverse rate kr0,and the cellular binding affinity Acmrm1Ka0.The adhesion frequency yielded P(t)=75%and 57%for RGD and KQAG DV peptides,respectively.We obtained Acmrm1Ka0=1.40 and kr0=0.32 s-1,for RGD,and Acmrm1Ka0=0.85 and kr0=0.54 s-1 for KQAGDV.The RGD peptide has a higher adhesion frequency and lower dissociation rate than the KQAGDV peptide.Electron microscopy techniques was used to observe the activation of integrins by peptides.Jurkat cell expressing integrins was bound to a magnetic bead and bottom plate which were coated with different integrin-binding peptides.Then,we manipulated the beads in a controlled direction by changing the magnetic field nearby,and the forces were applied to the cell.The target cells were fixed and then observed by scanning electron microscope or transmission electron microscope.Jurkat cells contain abundant flexible microvilli of which there are many parallel bundles of actin filaments inside.By electron microscopy analysis,the cell connected with magnetic bead coated with RGD were found to be protruded and the size of microvilli increased up to#-fold of the length of the KQAGDV sample.The microvilli exhibited a curved agglomerate structure under a force-free condition.Moreover,a higher proportion of cells were activated in the presence of RGD than KQAGDV.In conclusion,the binding affinity of KQAGDV to integrin is weaker than RGD,and KQAGDV can bind with integrins effectively with a lower activated proportion.Our results indicate the peptides may selectively bind to integrins without activating them. 展开更多
关键词 Force-Regulated ADHESION ACTIVATION Study INTEGRIN TARGETING polypeptides
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Alteration of Crystallin Polypeptides in Rat Lenses during the Development of Galactose-induced Cataract
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作者 Huiren Zhao Xiaoheng Ren Department of Biochemistry,Xuzhou Medical College Xuzhou 221002,China 《眼科学报》 1993年第3期143-145,共3页
Some striking differences in relative polypeptide abundanceof crystallins were observed in normal and galactose-induced cataractouslenses of rat by means of SDS-PAGE.In the cataractous lenses aprominent band appeared ... Some striking differences in relative polypeptide abundanceof crystallins were observed in normal and galactose-induced cataractouslenses of rat by means of SDS-PAGE.In the cataractous lenses aprominent band appeared at about 25 kDa and the αA chain increasedmarkedly,whereas the relative amount of the 31 kDa band decreasedsubstantially.These alterations are similar to the changes observed duringthe incubation of young mouse lenses in glucose-free medium.Eye Science1993;9:143-145. 展开更多
关键词 rat lens galactose cataract crystallin polypeptide
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A pancreatic player in dementia:pathological role for islet amyloid polypeptide accumulation in the brain
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作者 Angelina S.Bortoletto Ronald J.Parchem 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第10期2141-2146,共6页
Type 2 diabetes mellitus patients have a markedly higher risk of developing dementia.While multiple factors contribute to this predisposition,one of these involves the increased secretion of amylin,or islet amyloid po... Type 2 diabetes mellitus patients have a markedly higher risk of developing dementia.While multiple factors contribute to this predisposition,one of these involves the increased secretion of amylin,or islet amyloid polypeptide,that accompanies the pathophysiology of type 2 diabetes mellitus.Islet amyloid polypeptide accumulation has undoubtedly been implicated in various forms of dementia,including Alzheimer’s disease and vascular dementia,but the exact mechanisms underlying islet amyloid polypeptide’s causative role in dementia are unclear.In this review,we have summarized the literature supporting the various mechanisms by which islet amyloid polypeptide accumulation may cause neuronal damage,ultimately leading to the clinical symptoms of dementia.We discuss the evidence for islet amyloid polypeptide deposition in the brain,islet amyloid polypeptide interaction with other amyloids implicated in neurodegeneration,neuroinflammation caused by islet amyloid polypeptide deposition,vascular damage induced by islet amyloid polypeptide accumulation,and islet amyloid polypeptide-induced cytotoxicity.There are very few therapies approved for the treatment of dementia,and of these,clinical responses have been controversial at best.Therefore,investigating new,targetable pathways is vital for identifying novel therapeutic strategies for treating dementia.As such,we conclude this review by discussing islet amyloid polypeptide accumulation as a potential therapeutic target not only in treating type 2 diabetes mellitus but as a future target in treating or even preventing dementia associated with type 2 diabetes mellitus. 展开更多
关键词 Alzheimer’s disease AMYLIN AMYLOID DEMENTIA diabetes human islet amyloid polypeptide islet amyloid polypeptide PROTOFIBRILS type 2 diabetes mellitus vascular dementia
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Cationic polypeptides in a concept of oppositely charged polypeptides as prevention of postsurgical intraabdominal adhesions
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作者 Karolin Isaksson Daniel Akerberg +1 位作者 Katarzyna Said Bobby Tingstedt 《Journal of Biomedical Science and Engineering》 2011年第3期200-206,共7页
Background: Two differently charged polypeptides, α-poly-L-lysine and poly-L-glutamate, have previously been shown to effectively reduce postoperative intraabdominal adhesions. Though α-poly-L-lysine showed toxicity... Background: Two differently charged polypeptides, α-poly-L-lysine and poly-L-glutamate, have previously been shown to effectively reduce postoperative intraabdominal adhesions. Though α-poly-L-lysine showed toxicity in doses too close to the lowest therapeutic dose, the aim in the present study was to investigate the possible antiadhesive effect of another four cationic polypeptides. Materials/Methods: 125 mice were studied with a standardized and reproducible adhesion model and given epsilon poly-L-lysine, lactoferrin, lysozyme and polyarginine respectively in a combination with poly-L-glutamate. Epsilon poly-L-lysine was also tested in different concentrations and as single treatment. Results: All four cationic polypeptides above showed a significantly better anti-adhesive effect than the controls receiving saline (p<0.05). Epsilon poly-L-lysine had the best antiadhesive effect of the new substances tested in the experiment. Single treatment with the epsilon poly-L-lysine showed toxic side effects. Discussion: We have shown that epsilon poly-L-lysine, polyarginine, lysozyme and lactoferrin, in descending order, all can reduce postoperative intraabdominal adhesions in mice when combined with poly-L-glutamate. There were side effects of epsilon poly-L-lysine resembling those of α-poly-L-lysine, although less toxic. The antiadhesive effect of epsilon poly-L-lysine did not reach the level of α-poly-L-lysine. Further studies will concentrate on additional investigation, trying to modify the α-poly-L-lysine to lower its toxicity. The less toxic epsilon poly-L-lysine also needs further attention in our research of antiadhesive bioactive polypeptides. 展开更多
关键词 Postoperative Adhesions Bioactive polypeptides Molecular Structure
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Determined of antioxidant activity and preventing DNA damage effect of peanut polypeptides by chemiluminescence method
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作者 LIU Li-na LU Jing +1 位作者 HE Dong-ping ZHANG Sheng-hua 《Journal of Life Sciences》 2009年第9期43-48,共6页
关键词 DNA损伤 化学发光法 抗氧化活性 损伤效应 自由基清除能力 多肽 花生 超氧阴离子自由基
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响应面法优化长柄扁桃肽的酶解制备工艺
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作者 李聪 苏晨灿 +5 位作者 李皓瑜 魏冰 张煜 史宣明 陈邦 申烨华 《中国油脂》 CAS CSCD 北大核心 2024年第3期111-115,共5页
为高值化开发长柄扁桃种仁蛋白,以长柄扁桃种仁为原料,脱脂后提取水溶性蛋白,采用蛋白酶对其酶解制备长柄扁桃肽。通过比较5种蛋白酶对长柄扁桃水溶性蛋白水解度及酶解产物抗氧化活性的影响,优选合适的酶解用酶,在此基础上,采用单因素... 为高值化开发长柄扁桃种仁蛋白,以长柄扁桃种仁为原料,脱脂后提取水溶性蛋白,采用蛋白酶对其酶解制备长柄扁桃肽。通过比较5种蛋白酶对长柄扁桃水溶性蛋白水解度及酶解产物抗氧化活性的影响,优选合适的酶解用酶,在此基础上,采用单因素实验和响应面实验优化了长柄扁桃多肽的制备工艺。结果表明:采用碱性蛋白酶酶解可以得到更高的长柄扁桃蛋白水解度(16.03%)和酶解产物DPPH自由基清除率(59.49%),更适于长柄扁桃蛋白的酶解;长柄扁桃蛋白的最优酶解工艺条件为酶解温度57℃、酶解时间4 h、碱性蛋白酶用量1 192 U/g、pH 8.4,在此条件下长柄扁桃蛋白水解度为18.12%。酶解长柄扁桃蛋白制备多肽可提高长柄扁桃种仁的附加值,同时可为功能性肽产品提供优质原料。 展开更多
关键词 长柄扁桃 多肽 酶解 响应面优化
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鹿茸多肽对顺铂所致卵巢早衰大鼠卵巢功能的保护作用及其机制
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作者 史松 苏比努尔·买买提 +2 位作者 尼比热·阿布都瓦依提 杨静 易金玲 《中国病理生理杂志》 CAS CSCD 北大核心 2024年第7期1300-1306,共7页
目的:探讨鹿茸多肽(VAP)对顺铂(DDP)致卵巢早衰模型大鼠的影响及机制。方法:取动情周期正常的雌性大鼠并将其随机分为对照组、模型组、VAP干预组,每组各10只。模型组和VAP干预组通过连续20 d腹腔注射DDP(4 mg·kg^(−1)·d^(−1)... 目的:探讨鹿茸多肽(VAP)对顺铂(DDP)致卵巢早衰模型大鼠的影响及机制。方法:取动情周期正常的雌性大鼠并将其随机分为对照组、模型组、VAP干预组,每组各10只。模型组和VAP干预组通过连续20 d腹腔注射DDP(4 mg·kg^(−1)·d^(−1))建立卵巢早衰大鼠模型,干预组同时连续20 d灌胃VAP(400 mg·kg^(−1)·d^(−1))。HE染色观察卵巢形态学表现,并对各级发育卵泡计数。ELISA检测血清雌二醇(E2)、促卵泡生成素(FSH)、抗穆勒管激素(AMH)水平。生化法检测卵巢组织中谷胱甘肽(GSH)和丙二醛(MDA)水平。探针标记法检测卵巢组织中活性氧(ROS)水平。普鲁士蓝染色观察卵巢组织中铁蓄积情况并检测亚铁离子(Fe^(2+))水平。免疫组化和Western blot检验卵巢组织中溶质载体家族7成员11(SCL7A11)、谷胱甘肽过氧化酶4(GPX4)和酰基辅酶A合成酶长链家族成员4(ACSL4)的表达。通过生育力监测观察各组大鼠生育能力。结果:与对照组相比,模型组卵巢萎缩,铁蓄积(P<0.01),各级发育卵泡和总卵泡减少(P<0.05),闭锁卵泡增多(P<0.01),产仔数减少(P<0.01),血清E2、AMH水平降低(P<0.01),FSH水平提高(P<0.01),卵巢组织中GSH水平、SCL7A11和GPX4蛋白表达均降低(P<0.05),Fe^(2+)、MDA和ROS水平及ACSL4蛋白表达均升高(P<0.01)。与模型组相比,VAP能改善DDP导致的上述指标改变(P<0.01)。结论:鹿茸多肽可改善顺铂致卵巢早衰大鼠的卵巢功能、维持正常的卵泡发育并提高其生育能力,机制可能与脂质过氧化反应和铁死亡有关。 展开更多
关键词 鹿茸多肽 顺铂 卵巢早衰 脂质过氧化 铁死亡
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混菌发酵茶籽抗氧化肽的分离纯化及其功能活性研究
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作者 赵世光 储欣颖 +2 位作者 黎玮 张宇 薛正莲 《中国油脂》 CAS CSCD 北大核心 2024年第3期87-93,110,共8页
为促进茶叶籽资源的深度开发利用,采用不同截留分子质量的超滤膜对混菌发酵茶籽多肽产物进行分级分离,比较茶籽多肽的抗氧化活性与其分子质量的对应关系;利用凝胶过滤色谱技术对茶籽多肽逐级纯化,获得特征性茶籽抗氧化肽,对其二级结构... 为促进茶叶籽资源的深度开发利用,采用不同截留分子质量的超滤膜对混菌发酵茶籽多肽产物进行分级分离,比较茶籽多肽的抗氧化活性与其分子质量的对应关系;利用凝胶过滤色谱技术对茶籽多肽逐级纯化,获得特征性茶籽抗氧化肽,对其二级结构组成及相对含量进行分析,并考察其热稳定性和抗消化稳定性;以H_(2)O_(2)诱导小鼠胚胎成纤维细胞(MEF细胞)建立氧化损伤模型,评价茶籽抗氧化肽的细胞氧化损伤保护功能。结果表明:经超滤分级后,茶籽多肽的抗氧化活性与其分子质量呈负相关,分子质量小于1 kDa的TSP4组分具有最高的自由基清除能力;TSP4分子质量分布范围在90~849 Da之间,凝胶过滤色谱纯化得到的TSP4-b亚组分平均分子质量为446 Da,其二级结构中的β-折叠的相对含量从未发酵茶叶籽的16.59%上升至44.43%,α-螺旋则由未发酵茶叶籽的37.61%降至17.57%;TSP4-b经20~60℃热处理以及模拟胃肠消化后,自由基相对清除率仍可分别保持在90%及80%以上,具备良好的热稳定性及抗消化能力;中(0.5 mg/mL)、高(5.0 mg/mL)剂量的TSP4-b的介入可使H_(2)O_(2)诱导的MEF细胞存活率分别达到73.8%、82.4%。综上,所分离的茶籽抗氧化肽具有较强的抗氧化活性,对H_(2)O_(2)诱导的细胞损伤具有保护作用,在医药、保健食品等领域具有良好的发展潜力。 展开更多
关键词 茶籽多肽 分离纯化 功能活性 细胞氧化损伤
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