Ischemic stroke is the leading cause of death in China,accounting for approximately one-third of all stroke-associated deaths worldwide.Currently,thrombolysis is employed for ischemic strokes.However,due to the limite...Ischemic stroke is the leading cause of death in China,accounting for approximately one-third of all stroke-associated deaths worldwide.Currently,thrombolysis is employed for ischemic strokes.However,due to the limited therapeutic window of thrombolytic agents,most patients do not receive the drug at the right time.Moreover,these agents are associated with risks of hemorrhage and reperfusion damage.Herein,Angiopep-2(ANG)-black phosphorus(BP)-resveratrol(RES),a drug-loaded system,was used to deliver drugs across the blood–brain barrier(BBB).ANG-BP-RES has a uniform size,stable structure,good photothermal effect,and strong drug release ability under near-infrared(NIR)irradiation and acidic conditions.Furthermore,ANG-BP-RES can efficiently target the brain and improve BBB permeability,exerting a significant therapeutic effect against ischemic brain injury,especially after NIR irradiation.ANG-BP-RES is also biocompatible and shows minimal toxicity toward cells and tissues.This study offers novel insights into the therapeutic management of ischemic brain injury.展开更多
BACKGROUND As a member of the chaperonin-containing tailless complex polypeptide 1(TCP1)complex,which plays a pivotal role in ensuring the accurate folding of numerous proteins,chaperonin-containing TCP1 subunit 6A(CC...BACKGROUND As a member of the chaperonin-containing tailless complex polypeptide 1(TCP1)complex,which plays a pivotal role in ensuring the accurate folding of numerous proteins,chaperonin-containing TCP1 subunit 6A(CCT6A)participates in various physiological and pathological processes.However,its effects on cell death and cancer therapy and the underlying mechanisms need further exploration in colorectal cancer(CRC)cells.AIM To explore the effects of CCT6A on cell death and cancer therapy and the underlying mechanisms in CRC.METHODS Cell proliferation was evaluated using the MTS assay,EdU staining,and colony growth assays.The expression of CCT6A was monitored by immunoblotting and quantitative PCR.CCT6A was knocked out by CRISPR-Cas9,and overexpressed by transfecting plasmids.Autophagy was examined by immunoblotting and the mCherry-GFP-LC3 assay.To monitor apoptosis and necroptosis,immunoblotting,co-immunoprecipitation,and flow cytometry were employed.RESULTS Cisplatin(DDP)exerted cytotoxic effects on CRC cells while simultaneously downregulating the expression of CCT6A.Depletion of CCT6A amplified the cytotoxic effects of DDP,whereas overexpression of CCT6A attenuated these adverse effects.CCT6A suppressed autophagy,apoptosis,and necroptosis under both basal and DDP-treated conditions.Autophagy inhibitors significantly enhanced the cytotoxic effects of DDP,whereas a necroptosis inhibitor partially reversed the cell viability loss induced by DDP.Furthermore,inhibiting autophagy enhanced both apoptosis and necroptosis induced by DDP.CONCLUSION CCT6A negatively modulates autophagy,apoptosis,and necroptosis,and CCT6A confers resistance to DDP therapy in CRC,suggesting its potential as a therapeutic target.展开更多
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
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
In order to study the action mechanism of Sacha Inchi polypeptide in liquid crystal emulsion,oil-in-water liquid crystal emulsions with Sacha Inchi fermented polypeptide as the active component were prepared.The micro...In order to study the action mechanism of Sacha Inchi polypeptide in liquid crystal emulsion,oil-in-water liquid crystal emulsions with Sacha Inchi fermented polypeptide as the active component were prepared.The microstructures,particle sizes,stabilities,thermodynamic properties,and rheological properties of liquid crystal emulsions with different concentrations of the fermentation products were observed by Polarizing microscope,Particle size meter,Thermogravimetric differential thermal synchronous measurement system,and Rheometer,respectively.The results showed that the average particle size of fermented peptide liquid crystal emulsion was(25.7±2.8)μm,and the liquid crystal structure was complete and stable.The content of bound water and liquid crystal in the emulsion with 1%Sacha Inchi polypeptide were higher than those in the blank emulsion and the emulsions with 3%and 5%Sacha Inchi polypeptide.Rheological results indicated that the viscosity of liquid crystal emulsion with the change curve of shear rate registered the shear thinning phenomenon,which belongs to non-Newtonian fluid.The hysteresis area,energy storage modulus,and loss modulus of the 1%additive amount of liquid crystal emulsion were larger than those of the blank emulsion and the emulsions with 3%and 5%Sacha Inchi polypeptide,indicating greater thixotropy and stronger shear resistance.The hydrophilic amino acid residues of the peptide in the 1%additive amount of the emulsion were combined with the water phase,while the hydrophobic amino acid residues of the peptide entered the oil phase,which formed a viscoelastic film at the oil-water interface,so that the liquid crystal emulsion had a more stable gel network structure.展开更多
Excessive secretion of human islet amyloid polypeptide(hIAPP)is an important pathological basis of diabetic encephalopathy(DE).In this study,we aimed to investigate the potential implications of hIAPP in DE pathogenes...Excessive secretion of human islet amyloid polypeptide(hIAPP)is an important pathological basis of diabetic encephalopathy(DE).In this study,we aimed to investigate the potential implications of hIAPP in DE pathogenesis.Brain magnetic resonance imaging and cognitive scales were applied to evaluate white matter damage and cognitive function.We found that the concentration of serum hIAPP was positively correlated with white matter damage but negatively correlated with cognitive scores in patients with type 2 diabetes mellitus.In vitro assays revealed that oligodendrocytes,compared with neurons,were more prone to acidosis under exogenous hIAPP stimulation.Moreover,western blotting and co-immunoprecipitation indicated that hIAPP interfered with the binding process of monocarboxylate transporter(MCT)1 to its accessory protein CD147 but had no effect on the binding of MCT2 to its accessory protein gp70.Proteomic differential analysis of proteins co-immunoprecipitated with CD147 in oligodendrocytes revealed Yeast Rab GTPase-Interacting protein 2(YIPF2,which modulates the transfer of CD147 to the cell membrane)as a significant target.Furthermore,YIPF2 inhibition significantly improved hIAPP-induced acidosis in oligodendrocytes and alleviated cognitive dysfunction in DE model mice.These findings suggest that increased CD147 translocation by inhibition of YIPF2 optimizes MCT1 and CD147 binding,potentially ameliorating hIAPP-induced acidosis and the consequent DE-related demyelination.展开更多
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
Twenty-four-month-old male C57BU6 mice with low serum testosterone levels were used as a late-onset hypogonadism （LOH） animal model for examining the effects of velvet antler polypeptide （VAP） on sexual function a...Twenty-four-month-old male C57BU6 mice with low serum testosterone levels were used as a late-onset hypogonadism （LOH） animal model for examining the effects of velvet antler polypeptide （VAP） on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg-1 body weight per day （n = 10 mice per dose）. Control animals （n = 10） received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein （STAR）, cytochrome P450 cholesterol side-chain cleavage enzyme （P450scc）, and 3β-hydroxysteroid dehydrogenase （3βHSD） in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone （ITT） concentration also increased in the VAP-treated groups. The expression of STAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis （STAR, P450scc, and 3β-HSD） and the following promotion of testosterone syothesis in vivo.展开更多
AIM To investigate the relationship between hypoxia-inducible factor-1α(HIF-1α), prolyl 4-hydroxylase beta(P4 HB) expression, and clinicopathologic parameters, as well as the prognostic value of these genes for pati...AIM To investigate the relationship between hypoxia-inducible factor-1α(HIF-1α), prolyl 4-hydroxylase beta(P4 HB) expression, and clinicopathologic parameters, as well as the prognostic value of these genes for patients with gastric cancer(Gc).METHODS Hypoxia is a critical factor that shapes the Gc microenvironment. In previous reports, we have demonstrated that P4 HB is a potential target of HIF-1α. In the present study, gene expression profiling interactive analysis(GEPIA) was used to analyze the relationship between P4 HB and hypoxia-associated genes. To this end, 428 Gc tissue samples were used to analyze the expression of HIF-1α and P4 HB via immunohistochemical staining. Patient samples were classified as having weak-expression or over-expression both in terms of HIF-1α and P4 HB. Correlations between biomarkers and clinicopathological factors were analyzed to predict survival. RESULTS P4 HB demonstrated a positive correlation with hypoxiaassociated genes(P < 0.05). HIF-1α and P4 HB overexpression have a significant correlation with TNM staging(χ2 = 23.32, P = 0.00; χ2 = 65.64, P = 0.00) and peritoneum cavity metastasis(χ2 = 12.67, P = 0.00; χ2 = 39.29, P = 0.00). In univariate analysis, patients with a high HIF-1α expression trend had a shorter disease-free survival(DFS: 44.80 mo vs 22.06 mo) and overall survival(OS: 49.58 mo vs 39.92 mo). P4 HB overexpression reflected similar results: patients with over-expression of P4 HB had a shorter survival time than those with weak-expression(DFS: 48.03 mo vs 29.64 mo, OS: 52.48 mo vs 36.87 mo). Furthermore, HIF-1α is also a clinicopathological predictor of dismal prognosis according to multivariate analysis(DFS, 95%c I: 0.52-0.88, P < 0.00; OS, 95%c I: 0.50-0.85, P < 0.00). However, P4 HB was meaningful in DFS(95%c I: 0.58-1.00, P < 0.05) but not in OS(95%c I: 0.72-1.23, P > 0.05).CONCLUSION Overexpression of HIF-1α and P4 HB is associated with poor prognosis in patients with Gc. Thus, these genes may be potential prognostic biomarker candidates in GC.展开更多
OBJECTIVE: To investigate the efficacy and safety of intravenous cervus and cucumis polypeptides for treating avascular necrosis of the femoral head(ANFH) in regard to pain and hip function in a randomized clinical tr...OBJECTIVE: To investigate the efficacy and safety of intravenous cervus and cucumis polypeptides for treating avascular necrosis of the femoral head(ANFH) in regard to pain and hip function in a randomized clinical trial.METHODS: A total of 96 subjects with ANFH who were recruited at the Orthopaedic Hospital Affiliated with Hebei United University and Qian Hai Femoral Head Hospital of Beijing were assigned by lottery to an intervention group(n = 48) or a control group(n = 48). All subjects underwent physical therapy and rehabilitation exercises. In addition,subjects in the intervention group were given intravenous infusions of cervus and cucumis polypeptides. Visual analogue scale(VAS), Harris hip score,and radiography or magnetic resonance imaging were applied to assess all subjects at the beginning of treatment and 3, 6, and 9 months afterward. All the subjects were followed up for 2 years.RESULTS: At the beginning of treatment, there were no statistically significant differences between the two groups in terms of the general condition of patients or the VAS and Harris hip scores(all P > 0.05). At 3, 6, and 9 months after treatment,however, the VAS score decreased and the Harris hip score increased in all patients, with the improvement of intervention group significantly greater than that of the control group(P < 0.05).The total effectiveness rates for the intervention and control groups were 89.58% and 70.83%, respectively, with the difference being statistically significant(P < 0.05). There was no statistically significant difference between the two groups in terms of the safety of the injections(P > 0.05).CONCLUSION: Intravenous infusion of cervus and cucumis polypeptides relieved pain and improved hip function of subjects with ANFH.Thus, the intravenous infusion of cervus and cucumis polypeptides was a safe, effective treatment for ANFH.展开更多
AIM: To investigate the effects of psychological stress on small intestinal motility and expression of cholecystokinin (CCK) and vasoactive intestinal polypeptide (VIP) in plasma and small intestine, and to explore th...AIM: To investigate the effects of psychological stress on small intestinal motility and expression of cholecystokinin (CCK) and vasoactive intestinal polypeptide (VIP) in plasma and small intestine, and to explore the relationship between small intestinal motor disorders and gastrointestinal hormones under psychological stress. METHODS: Thirty-six mice were randomly divided into psychological stress group and control group. A mouse model with psychological stress was established by housing the mice with a hungry cat in separate layers of a two-layer cage. A semi-solid colored marker (carbon-ink) was used for monitoring small intestinal transit. CCK and VIP levels in plasma and small intestine in mice were measured by radioimmunoassay (RIA). RESULTS: Small intestinal transit was inhibited (52.18±19.15% vs70.19±17.79%, P<0.01) in mice after psychological stress, compared to the controls. Small intestinal CCK levels in psychological stress mice were significantly lower than those in the control group (0.75±0.53 μg/g vs1.98±1.17 μg/g, P<0.01), whereas plasma CCK concentrations were not different between the groups. VIP levels in small intestine were significantly higher in psychological stress mice than those in the control group (8.45±1.09 μg/g vs7.03±2.36 μg/g, P<0.01), while there was no significant difference in plasma VIP levels between the two groups. CONCLUSION: Psychological stress inhibits the small intestinal transit, probably by down-regulating CCK and up-regulating VIP expression in small intestine.展开更多
We developed one-pot photoreduction strategy to prepare near infrared light(NIR)-absorbing plasmonic gold nanoparticles(Au NPs) tethered by amphiphilic polypeptide copolymer poly(L-cysteine)-b-poly(ethylene oxide)(PLC...We developed one-pot photoreduction strategy to prepare near infrared light(NIR)-absorbing plasmonic gold nanoparticles(Au NPs) tethered by amphiphilic polypeptide copolymer poly(L-cysteine)-b-poly(ethylene oxide)(PLC-b-PEO). The PLC-b-PEO@Au NPs possessed strong NIR absorption at 700–1100 nm and ultrahigh photothermal conversion efficiency of 62.1%. Upon the NIR irradiation(808nm,2 W/cm^2,5 min), the PLC-b-PEO@Au NPs(1mg/mL) sharply attained an elevation of 30.8℃ and the hyperthermia effect could efficiently kill cancer cells in vitro. As for the PT-CT treatment, the doxorubicin(DOX)-loaded nanoparticles of DOX-PLC-b-PEO@Au NPs gave a combination index of 0.9 compared to single chemotherapy(CT) or photothermal therapy(PT), demonstrating a synergistic effect.展开更多
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
Gram-negative bacteria can cause serious infections and are well known problems in biomedical practices. Biofilms of gramnegative bacteria are notorious for their frequently encountered resistance toward antibiotics. ...Gram-negative bacteria can cause serious infections and are well known problems in biomedical practices. Biofilms of gramnegative bacteria are notorious for their frequently encountered resistance toward antibiotics. We demonstrate that α/β chimeric polypeptide molecular brush (α/β CPMB) exerts potent activities against antibiotic-resistant gram-negative bacteria. MTT viability assay, bacterial colony counting, and live/dead staining all indicate that α/β CPMB not only inhibits biofilm formation of gram-negative Pseudomonas aeruginosa and Acinetobacter baumannii, but also effectively disrupts mature biofllms that are highly resistant to one of the most active antibiotics-colistin. The superior antibacterial performance of the α/β CPMB implies its potential topical applications in treating biofilms.展开更多
We report on the fabrication of self-assembled micelles from ABC-type miktoarm star polypeptide hybrid copolymers consisting of poly（ethylene oxide）, poly（L-lysine）, and poly（e-caprolactone） arms, PEO（-b-PLL）-...We report on the fabrication of self-assembled micelles from ABC-type miktoarm star polypeptide hybrid copolymers consisting of poly（ethylene oxide）, poly（L-lysine）, and poly（e-caprolactone） arms, PEO（-b-PLL）-b-PCL, and their functional applications as co-delivery nanocarriers of chemotherapeutic drugs and plasmid DNA. Miktoarm star copolymer precursors, PEO（-b-PZLL）-b-PCL, were synthesized at first via the combination of consecutive ＂click＂ reactions and ring-opening polymerizations （ROP）, where PZLL is poly（e-benzyloxycarbonyl-L-lysine）. Subsequently, the deprotection of PZLL arm afforded amphiphilic miktoarm star copolymers, PEO（-b-PLL）-b-PCL. In aqueous media at pH 7.4, PEO（-b-PLL）-b-PCL self-assembles into micelles consisting of PCL cores and hydrophilic PEO/PLL hybrid coronas. The hydrophobic micellar cores can effectively encapsulate model hydrophobic anticancer drug, paclitaxel; whereas positively charged PLL arms within mixed micellar corona are capable of forming electrostatic polyplexes with negatively charged plasmid DNA （pDNA） at N/P ratios higher than ca. 2. Thus, PEO（-b-PLL）-b-PCL micelles can act as co-delivery nanovehicles for both chemotherapeutic drugs and genes. Furthermore, polyplexes of pDNA with paclitaxel-loaded PEO（-b- PLL）-b-PCL micelles exhibited improved transfection efficiency compared to that of pDNA/blank micelles. We expect that the reported strategy of varying chain topologies for the fabrication of co-delivery polymeric nanocarriers can be further applied to integrate with other advantageous functions such as targeting, imaging, and diagnostics.展开更多
Alzheimer’s disease(AD)is a neurodegenerative disorder that affects millions worldwide.Due to population ageing,the incidence of AD is increasing.AD patients develop cognitive decline and dementia,features for which ...Alzheimer’s disease(AD)is a neurodegenerative disorder that affects millions worldwide.Due to population ageing,the incidence of AD is increasing.AD patients develop cognitive decline and dementia,features for which is known,requiring permanent care.This poses a major socio-economic burden on healthcare systems as AD patients’relatives and healthcare workers are forced to cope with rising numbers of affected people.Despite recent advances,AD pathological mechanisms are not fully understood.Nevertheless,it is clear that the amyloid beta(Aβ)peptide,which forms amyloid plaques in AD patients’brains,plays a key role.Type 2 diabetes,the most common form of diabetes,affects hundreds of million people globally.Islet amyloid polypeptide(IAPP)is a hormone coproduced and secreted with insulin in pancreatic β-cells,with a key role in diabetes,as it helps regulate glucose levels and control adiposity and satiation.Similarly to Aβ,IAPP is very amyloidogenic,generating intracellular amyloid deposits that causeβ-cell dysfunction and death.It is now clear that IAPP can also have a pathological role in AD,decreasing cognitive function.IAPP harms the blood-brain barrier,directly interacts and co-deposits with Aβ,promoting diabetes-associated dementia.IAPP can cause a metabolic dysfunction in the brain,leading to other diabetes-related forms of AD.Thus,here we discuss IAPP association with diabetes,Aβand dementia,in the context of what we designate a“diabetes brain phenotype”AD hypothesis.Such approach helps to set a conceptual framework for future IAPP-based drugs against AD.展开更多
Polypeptide from Chlamys farreri(PCF) is a novel marine bioactive product that was isolated from the gonochoric Chinese scallop Chlamys farreri,and was found to be an effective antioxidant in our recent studies.In thi...Polypeptide from Chlamys farreri(PCF) is a novel marine bioactive product that was isolated from the gonochoric Chinese scallop Chlamys farreri,and was found to be an effective antioxidant in our recent studies.In this study,we investigated the effect of PCF on ultraviolet B(UVB)-induced apoptosis of HaCaT cells and the intracellular signaling pathways involved.Pretreatment with the inducible nitric oxide synthase(iNOS) inhibitor S-methylisothiourea sulfate inhibited UVB-induced apoptosis,indicating that iNOS and NO play important roles in apoptosis.On the other hand,the inhibition of UVB-induced apoptosis in the immortalized keratinocyte(HaCaT) cells by PCF was estimated using a DNA ladder.PCF treatment inhibited UVB-induced iNOS activation,as determined by RT-PCR,NO production,as determined by ESR,and up-regulated heat shock protein(HSP) 90 activation,as determined by Western blotting.Our results indicate that iNOS and NO are involved in UVB-induced apoptosis of HaCaT cells and the protective effect of PCF against UVB irradiation is exerted by suppressing the expression of iNOS,followed by inhibition of NO release and enhanced activation of HSP90.展开更多
Polypeptides are one kind of promising biodegradable and biocompatible biomedical polymers with the structural units of various a-amino acids.Polypeptides were first polymerized by the ring-opening polymerization(ROP)...Polypeptides are one kind of promising biodegradable and biocompatible biomedical polymers with the structural units of various a-amino acids.Polypeptides were first polymerized by the ring-opening polymerization(ROP)of α-amino acid N-carboxyanhydrides(NCAs)by Leuchs and Hermann in 1906.In the past decades,several effective strategies,including the selection of initiators,the adjustment of reaction conditions,and the introduction of catalysts,have been reported to improve the controllability of the ROP of various a-amino acid NCAs to synthesize different polypeptides with precise chemical structures and low polydispersity indexes.In this Review,the strategies,mechanisms,challenges,and opportunities for controlled synthesis of polypeptides by the ROP of differentα-amino acid NCAs have been declared.展开更多
Polypeptides have been widely utilized in the fields of biomaterials and biomedicine.Ever since N-carboxyanhydride(NCA)was reported by Hermann Leuchs in 1906,ring-opening polymerization of NCAS has been extensively us...Polypeptides have been widely utilized in the fields of biomaterials and biomedicine.Ever since N-carboxyanhydride(NCA)was reported by Hermann Leuchs in 1906,ring-opening polymerization of NCAS has been extensively used to prepare polypeptides.Despite continuous innovations,it is still challenging to synthesize polypeptides in high molecular weight fficiently.To address this challenge,we developed KHMDS/NaHMDS initiated fast NCA polymerization that is also moisture tolerant,open-flask amenable and terminal tunable.This NCA polymerization was able to proceed in most common solvents and meet the solubility requirement of variable NCA monomers and corresponding polypeptides.KHMDS can initiate r benzy-L glutamate-N carboxyanhydride(BLG NCA)polymerization in a reaction rate 92 times faster than does hexylamine and 80 times faster than does triethylamine.This NCA polymerization also demonstrated easy and fast synthesis of gram-scale long chain polypeptides in an open flask.展开更多
To construct an eukaryotic expressing vector that expresses CH50, a recombinant CellⅠ HepⅡ bifunctional domain polypeptide of human fibronectin, and to investigate the chemotaxis to immune cells and the inhibitor...To construct an eukaryotic expressing vector that expresses CH50, a recombinant CellⅠ HepⅡ bifunctional domain polypeptide of human fibronectin, and to investigate the chemotaxis to immune cells and the inhibitory effect on the growth of tumor by the expression of the plasmid in vivo , the plasmid was constructed by DNA recombination. Gene transfection was performed in vitro and in vivo . The expressed product was identified by Western blot. The chemotaxis after gene transfection in vivo was observed by histotomy and staining of muscle tissues. The inhibition of gene transfection on solid tumor was observed in mice. The results showed that plasmid pCH510 was constructed by the recombination of the 5′ terminal noncoding region and signal peptide coding region of human fibronectin cDNA and cDNA fragment coding CH50 polypeptide with a 3′ terminal noncoding region of human FN cDNA, and the insertion of the recombinated fragment into plasmid pcDNA3.1. After transfection with plasmid pCH510, NIH3T3 cells could produce CH50 polypeptide. The transfection of plasmid pCH510 by the injection in muscle of mouse could produce the effects of chemotaxis on immune cells and the inhibition on the growth of solid tumor. It is concluded that plasmid pCH510 can express in cells and in vivo in mouse. The expression of the plasmid in vivo has a chemotactic effect on immune cells and can inhibit the growth of solid tumor.展开更多
基金funded by the National Natural Science Foundation of China (No. 81960334)the Guiding Plan of Xinjiang Production Construction Corps (No. 2022ZD007)+4 种基金the Science and Technology Innovation Leading Talents Program of Guangdong Province (No. 2019TX05C343)the Basic and Applied Basic Research Foundation of Guangdong Province-Regional Joint Fund-Key Projects (No. 2019B1515120043)the Project supported by the State Key Laboratory of Luminescence and Applications (No. SKLA-2020-03)the support from Instrumental Analysis Center of Shenzhen University (Xili Campus)Instrumental Analysis Center of Shihezi University.
文摘Ischemic stroke is the leading cause of death in China,accounting for approximately one-third of all stroke-associated deaths worldwide.Currently,thrombolysis is employed for ischemic strokes.However,due to the limited therapeutic window of thrombolytic agents,most patients do not receive the drug at the right time.Moreover,these agents are associated with risks of hemorrhage and reperfusion damage.Herein,Angiopep-2(ANG)-black phosphorus(BP)-resveratrol(RES),a drug-loaded system,was used to deliver drugs across the blood–brain barrier(BBB).ANG-BP-RES has a uniform size,stable structure,good photothermal effect,and strong drug release ability under near-infrared(NIR)irradiation and acidic conditions.Furthermore,ANG-BP-RES can efficiently target the brain and improve BBB permeability,exerting a significant therapeutic effect against ischemic brain injury,especially after NIR irradiation.ANG-BP-RES is also biocompatible and shows minimal toxicity toward cells and tissues.This study offers novel insights into the therapeutic management of ischemic brain injury.
基金Supported by Shandong Provincial Natural Science Foundation,No.ZR2023MH329Project of Shandong Province Higher Educational Youth Innovation Science and Technology Program,No.2023KJ263and Natural Science Foundation of Gansu Province,China,No.22JR5RA953.
文摘BACKGROUND As a member of the chaperonin-containing tailless complex polypeptide 1(TCP1)complex,which plays a pivotal role in ensuring the accurate folding of numerous proteins,chaperonin-containing TCP1 subunit 6A(CCT6A)participates in various physiological and pathological processes.However,its effects on cell death and cancer therapy and the underlying mechanisms need further exploration in colorectal cancer(CRC)cells.AIM To explore the effects of CCT6A on cell death and cancer therapy and the underlying mechanisms in CRC.METHODS Cell proliferation was evaluated using the MTS assay,EdU staining,and colony growth assays.The expression of CCT6A was monitored by immunoblotting and quantitative PCR.CCT6A was knocked out by CRISPR-Cas9,and overexpressed by transfecting plasmids.Autophagy was examined by immunoblotting and the mCherry-GFP-LC3 assay.To monitor apoptosis and necroptosis,immunoblotting,co-immunoprecipitation,and flow cytometry were employed.RESULTS Cisplatin(DDP)exerted cytotoxic effects on CRC cells while simultaneously downregulating the expression of CCT6A.Depletion of CCT6A amplified the cytotoxic effects of DDP,whereas overexpression of CCT6A attenuated these adverse effects.CCT6A suppressed autophagy,apoptosis,and necroptosis under both basal and DDP-treated conditions.Autophagy inhibitors significantly enhanced the cytotoxic effects of DDP,whereas a necroptosis inhibitor partially reversed the cell viability loss induced by DDP.Furthermore,inhibiting autophagy enhanced both apoptosis and necroptosis induced by DDP.CONCLUSION CCT6A negatively modulates autophagy,apoptosis,and necroptosis,and CCT6A confers resistance to DDP therapy in CRC,suggesting its potential as a therapeutic target.
文摘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.
基金sponsored by the National Key R&D Program of China (2018YFD0901102)the Natural Science Foundation of Zhejiang Province (LQ22D060002)+2 种基金the Fund of State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products (ZS20190105)the Fundamental Research Funds for the Provincial Universities of Zhejiang (SJLY2021015)the K.C.Wong Magna Fund of Ningbo University。
文摘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.
文摘In order to study the action mechanism of Sacha Inchi polypeptide in liquid crystal emulsion,oil-in-water liquid crystal emulsions with Sacha Inchi fermented polypeptide as the active component were prepared.The microstructures,particle sizes,stabilities,thermodynamic properties,and rheological properties of liquid crystal emulsions with different concentrations of the fermentation products were observed by Polarizing microscope,Particle size meter,Thermogravimetric differential thermal synchronous measurement system,and Rheometer,respectively.The results showed that the average particle size of fermented peptide liquid crystal emulsion was(25.7±2.8)μm,and the liquid crystal structure was complete and stable.The content of bound water and liquid crystal in the emulsion with 1%Sacha Inchi polypeptide were higher than those in the blank emulsion and the emulsions with 3%and 5%Sacha Inchi polypeptide.Rheological results indicated that the viscosity of liquid crystal emulsion with the change curve of shear rate registered the shear thinning phenomenon,which belongs to non-Newtonian fluid.The hysteresis area,energy storage modulus,and loss modulus of the 1%additive amount of liquid crystal emulsion were larger than those of the blank emulsion and the emulsions with 3%and 5%Sacha Inchi polypeptide,indicating greater thixotropy and stronger shear resistance.The hydrophilic amino acid residues of the peptide in the 1%additive amount of the emulsion were combined with the water phase,while the hydrophobic amino acid residues of the peptide entered the oil phase,which formed a viscoelastic film at the oil-water interface,so that the liquid crystal emulsion had a more stable gel network structure.
基金supported by the National Natural Science Foundation of China (82100863)Hebei Natural Science Foundation (H2020206643 and H2020206105)+3 种基金Funding project for introducing overseas students of Hebei Province (C20210346)Medical Science Research Project of Hebei Province (20211628)Hebei Province Government-funded Excellent Talents Project in Clinical Medicine (ZF2023029)Spark Scientific Research Project of the First Hospital of Hebei Medical University (XH202004).
文摘Excessive secretion of human islet amyloid polypeptide(hIAPP)is an important pathological basis of diabetic encephalopathy(DE).In this study,we aimed to investigate the potential implications of hIAPP in DE pathogenesis.Brain magnetic resonance imaging and cognitive scales were applied to evaluate white matter damage and cognitive function.We found that the concentration of serum hIAPP was positively correlated with white matter damage but negatively correlated with cognitive scores in patients with type 2 diabetes mellitus.In vitro assays revealed that oligodendrocytes,compared with neurons,were more prone to acidosis under exogenous hIAPP stimulation.Moreover,western blotting and co-immunoprecipitation indicated that hIAPP interfered with the binding process of monocarboxylate transporter(MCT)1 to its accessory protein CD147 but had no effect on the binding of MCT2 to its accessory protein gp70.Proteomic differential analysis of proteins co-immunoprecipitated with CD147 in oligodendrocytes revealed Yeast Rab GTPase-Interacting protein 2(YIPF2,which modulates the transfer of CD147 to the cell membrane)as a significant target.Furthermore,YIPF2 inhibition significantly improved hIAPP-induced acidosis in oligodendrocytes and alleviated cognitive dysfunction in DE model mice.These findings suggest that increased CD147 translocation by inhibition of YIPF2 optimizes MCT1 and CD147 binding,potentially ameliorating hIAPP-induced acidosis and the consequent DE-related demyelination.
基金supported by The Mike Hogg FundBaylor College of Medicine Medical Scientist Training Program,NICHD R01HD099252(to RJP)and R01HD098131(to RJP)the NHLBI T32 HL092332(to ASB)。
文摘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.
基金This work was supported by the National Natural Science Foundation of China （No. 81302223） and the Medical Scientific Research Foundation of Guangdong Province, China （B2013104）.
文摘Twenty-four-month-old male C57BU6 mice with low serum testosterone levels were used as a late-onset hypogonadism （LOH） animal model for examining the effects of velvet antler polypeptide （VAP） on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg-1 body weight per day （n = 10 mice per dose）. Control animals （n = 10） received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein （STAR）, cytochrome P450 cholesterol side-chain cleavage enzyme （P450scc）, and 3β-hydroxysteroid dehydrogenase （3βHSD） in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone （ITT） concentration also increased in the VAP-treated groups. The expression of STAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis （STAR, P450scc, and 3β-HSD） and the following promotion of testosterone syothesis in vivo.
基金Supported by Liaoning S and T Project,No.2015020269Doctor fund of Liaoning Province Cancer Hospital and Institute,No.Z1410
文摘AIM To investigate the relationship between hypoxia-inducible factor-1α(HIF-1α), prolyl 4-hydroxylase beta(P4 HB) expression, and clinicopathologic parameters, as well as the prognostic value of these genes for patients with gastric cancer(Gc).METHODS Hypoxia is a critical factor that shapes the Gc microenvironment. In previous reports, we have demonstrated that P4 HB is a potential target of HIF-1α. In the present study, gene expression profiling interactive analysis(GEPIA) was used to analyze the relationship between P4 HB and hypoxia-associated genes. To this end, 428 Gc tissue samples were used to analyze the expression of HIF-1α and P4 HB via immunohistochemical staining. Patient samples were classified as having weak-expression or over-expression both in terms of HIF-1α and P4 HB. Correlations between biomarkers and clinicopathological factors were analyzed to predict survival. RESULTS P4 HB demonstrated a positive correlation with hypoxiaassociated genes(P < 0.05). HIF-1α and P4 HB overexpression have a significant correlation with TNM staging(χ2 = 23.32, P = 0.00; χ2 = 65.64, P = 0.00) and peritoneum cavity metastasis(χ2 = 12.67, P = 0.00; χ2 = 39.29, P = 0.00). In univariate analysis, patients with a high HIF-1α expression trend had a shorter disease-free survival(DFS: 44.80 mo vs 22.06 mo) and overall survival(OS: 49.58 mo vs 39.92 mo). P4 HB overexpression reflected similar results: patients with over-expression of P4 HB had a shorter survival time than those with weak-expression(DFS: 48.03 mo vs 29.64 mo, OS: 52.48 mo vs 36.87 mo). Furthermore, HIF-1α is also a clinicopathological predictor of dismal prognosis according to multivariate analysis(DFS, 95%c I: 0.52-0.88, P < 0.00; OS, 95%c I: 0.50-0.85, P < 0.00). However, P4 HB was meaningful in DFS(95%c I: 0.58-1.00, P < 0.05) but not in OS(95%c I: 0.72-1.23, P > 0.05).CONCLUSION Overexpression of HIF-1α and P4 HB is associated with poor prognosis in patients with Gc. Thus, these genes may be potential prognostic biomarker candidates in GC.
基金Supported by Tangshan Science and Technology Research Project(No.13130242b)
文摘OBJECTIVE: To investigate the efficacy and safety of intravenous cervus and cucumis polypeptides for treating avascular necrosis of the femoral head(ANFH) in regard to pain and hip function in a randomized clinical trial.METHODS: A total of 96 subjects with ANFH who were recruited at the Orthopaedic Hospital Affiliated with Hebei United University and Qian Hai Femoral Head Hospital of Beijing were assigned by lottery to an intervention group(n = 48) or a control group(n = 48). All subjects underwent physical therapy and rehabilitation exercises. In addition,subjects in the intervention group were given intravenous infusions of cervus and cucumis polypeptides. Visual analogue scale(VAS), Harris hip score,and radiography or magnetic resonance imaging were applied to assess all subjects at the beginning of treatment and 3, 6, and 9 months afterward. All the subjects were followed up for 2 years.RESULTS: At the beginning of treatment, there were no statistically significant differences between the two groups in terms of the general condition of patients or the VAS and Harris hip scores(all P > 0.05). At 3, 6, and 9 months after treatment,however, the VAS score decreased and the Harris hip score increased in all patients, with the improvement of intervention group significantly greater than that of the control group(P < 0.05).The total effectiveness rates for the intervention and control groups were 89.58% and 70.83%, respectively, with the difference being statistically significant(P < 0.05). There was no statistically significant difference between the two groups in terms of the safety of the injections(P > 0.05).CONCLUSION: Intravenous infusion of cervus and cucumis polypeptides relieved pain and improved hip function of subjects with ANFH.Thus, the intravenous infusion of cervus and cucumis polypeptides was a safe, effective treatment for ANFH.
文摘AIM: To investigate the effects of psychological stress on small intestinal motility and expression of cholecystokinin (CCK) and vasoactive intestinal polypeptide (VIP) in plasma and small intestine, and to explore the relationship between small intestinal motor disorders and gastrointestinal hormones under psychological stress. METHODS: Thirty-six mice were randomly divided into psychological stress group and control group. A mouse model with psychological stress was established by housing the mice with a hungry cat in separate layers of a two-layer cage. A semi-solid colored marker (carbon-ink) was used for monitoring small intestinal transit. CCK and VIP levels in plasma and small intestine in mice were measured by radioimmunoassay (RIA). RESULTS: Small intestinal transit was inhibited (52.18±19.15% vs70.19±17.79%, P<0.01) in mice after psychological stress, compared to the controls. Small intestinal CCK levels in psychological stress mice were significantly lower than those in the control group (0.75±0.53 μg/g vs1.98±1.17 μg/g, P<0.01), whereas plasma CCK concentrations were not different between the groups. VIP levels in small intestine were significantly higher in psychological stress mice than those in the control group (8.45±1.09 μg/g vs7.03±2.36 μg/g, P<0.01), while there was no significant difference in plasma VIP levels between the two groups. CONCLUSION: Psychological stress inhibits the small intestinal transit, probably by down-regulating CCK and up-regulating VIP expression in small intestine.
基金The National Natural Science Foundation of China (No. 21474061)The Innovation Fund (No. IFPM2016B004) of Shanghai Jiao Tong University & Affiliated Sixth People's Hospital South Campus are appreciated
文摘We developed one-pot photoreduction strategy to prepare near infrared light(NIR)-absorbing plasmonic gold nanoparticles(Au NPs) tethered by amphiphilic polypeptide copolymer poly(L-cysteine)-b-poly(ethylene oxide)(PLC-b-PEO). The PLC-b-PEO@Au NPs possessed strong NIR absorption at 700–1100 nm and ultrahigh photothermal conversion efficiency of 62.1%. Upon the NIR irradiation(808nm,2 W/cm^2,5 min), the PLC-b-PEO@Au NPs(1mg/mL) sharply attained an elevation of 30.8℃ and the hyperthermia effect could efficiently kill cancer cells in vitro. As for the PT-CT treatment, the doxorubicin(DOX)-loaded nanoparticles of DOX-PLC-b-PEO@Au NPs gave a combination index of 0.9 compared to single chemotherapy(CT) or photothermal therapy(PT), demonstrating a synergistic effect.
基金supported by the National Natural Science Foundation of China,No.81073079(to HMS)the Natural Science Foundation of the Jiangsu Higher Education Institute of China,No.18KJA180009(to HMS)the Science Foundation of Nantong City of China,No.MS12018043(to HMS)
文摘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.
基金financially supported by the National Natural Science Foundation of China (Nos. 21574038, 21774031, and 21861162010)the Natural Science Foundation of Shanghai (No. 18ZR1410300)+2 种基金the “Eastern Scholar Professorship” from Shanghai local government (No. TP2014034)the national special fund for State Key Laboratory of Bioreactor Engineering (No. 2060204)the Fundamental Research Funds for the Central Universities (No. 22221818014)
文摘Gram-negative bacteria can cause serious infections and are well known problems in biomedical practices. Biofilms of gramnegative bacteria are notorious for their frequently encountered resistance toward antibiotics. We demonstrate that α/β chimeric polypeptide molecular brush (α/β CPMB) exerts potent activities against antibiotic-resistant gram-negative bacteria. MTT viability assay, bacterial colony counting, and live/dead staining all indicate that α/β CPMB not only inhibits biofilm formation of gram-negative Pseudomonas aeruginosa and Acinetobacter baumannii, but also effectively disrupts mature biofllms that are highly resistant to one of the most active antibiotics-colistin. The superior antibacterial performance of the α/β CPMB implies its potential topical applications in treating biofilms.
基金supported by the National Natural Science Foundation of China (Nos. 21274137, 91027026 and 51033005)Fundamental Research Funds for the Central UniversitiesSpecialized Research Fund for the Doctoral Program of Higher Education (SRFDP, 20123402130010)
文摘We report on the fabrication of self-assembled micelles from ABC-type miktoarm star polypeptide hybrid copolymers consisting of poly（ethylene oxide）, poly（L-lysine）, and poly（e-caprolactone） arms, PEO（-b-PLL）-b-PCL, and their functional applications as co-delivery nanocarriers of chemotherapeutic drugs and plasmid DNA. Miktoarm star copolymer precursors, PEO（-b-PZLL）-b-PCL, were synthesized at first via the combination of consecutive ＂click＂ reactions and ring-opening polymerizations （ROP）, where PZLL is poly（e-benzyloxycarbonyl-L-lysine）. Subsequently, the deprotection of PZLL arm afforded amphiphilic miktoarm star copolymers, PEO（-b-PLL）-b-PCL. In aqueous media at pH 7.4, PEO（-b-PLL）-b-PCL self-assembles into micelles consisting of PCL cores and hydrophilic PEO/PLL hybrid coronas. The hydrophobic micellar cores can effectively encapsulate model hydrophobic anticancer drug, paclitaxel; whereas positively charged PLL arms within mixed micellar corona are capable of forming electrostatic polyplexes with negatively charged plasmid DNA （pDNA） at N/P ratios higher than ca. 2. Thus, PEO（-b-PLL）-b-PCL micelles can act as co-delivery nanovehicles for both chemotherapeutic drugs and genes. Furthermore, polyplexes of pDNA with paclitaxel-loaded PEO（-b- PLL）-b-PCL micelles exhibited improved transfection efficiency compared to that of pDNA/blank micelles. We expect that the reported strategy of varying chain topologies for the fabrication of co-delivery polymeric nanocarriers can be further applied to integrate with other advantageous functions such as targeting, imaging, and diagnostics.
基金supported by iNOVA4Health-UID/Multi/04462/2019,a program financially supported by Fundação para a Ciência e Tecnologia/Ministério da Educação e Ciência,through national funds and co-funded by FEDER under the PT2020 Partnership Agreement,Funding from INTERFACE Programme,through the Innovation,Technology and Circular Economy Fund(FITEC),FCT via PTDC/BIA-MOL/31104/2017 and UID/Multi/04462/2019-SubProj iNOVA4Health C44(to RM),PD/BD/135504/2018(to AFR)Sociedade Portuguesa de Diabetologia for the Nuno Castelo-Branco Prize-2016(to RM),and ICM acknowledges FCT-MCTES Program“Concurso de Estímulo ao Emprego Científico”(CEECIND/01670/2017).
文摘Alzheimer’s disease(AD)is a neurodegenerative disorder that affects millions worldwide.Due to population ageing,the incidence of AD is increasing.AD patients develop cognitive decline and dementia,features for which is known,requiring permanent care.This poses a major socio-economic burden on healthcare systems as AD patients’relatives and healthcare workers are forced to cope with rising numbers of affected people.Despite recent advances,AD pathological mechanisms are not fully understood.Nevertheless,it is clear that the amyloid beta(Aβ)peptide,which forms amyloid plaques in AD patients’brains,plays a key role.Type 2 diabetes,the most common form of diabetes,affects hundreds of million people globally.Islet amyloid polypeptide(IAPP)is a hormone coproduced and secreted with insulin in pancreatic β-cells,with a key role in diabetes,as it helps regulate glucose levels and control adiposity and satiation.Similarly to Aβ,IAPP is very amyloidogenic,generating intracellular amyloid deposits that causeβ-cell dysfunction and death.It is now clear that IAPP can also have a pathological role in AD,decreasing cognitive function.IAPP harms the blood-brain barrier,directly interacts and co-deposits with Aβ,promoting diabetes-associated dementia.IAPP can cause a metabolic dysfunction in the brain,leading to other diabetes-related forms of AD.Thus,here we discuss IAPP association with diabetes,Aβand dementia,in the context of what we designate a“diabetes brain phenotype”AD hypothesis.Such approach helps to set a conceptual framework for future IAPP-based drugs against AD.
基金Supported by the National Natural Science Foundation of China (30471458)National Natural Science Foundation of Shandong Province (Z2007c09)
文摘Polypeptide from Chlamys farreri(PCF) is a novel marine bioactive product that was isolated from the gonochoric Chinese scallop Chlamys farreri,and was found to be an effective antioxidant in our recent studies.In this study,we investigated the effect of PCF on ultraviolet B(UVB)-induced apoptosis of HaCaT cells and the intracellular signaling pathways involved.Pretreatment with the inducible nitric oxide synthase(iNOS) inhibitor S-methylisothiourea sulfate inhibited UVB-induced apoptosis,indicating that iNOS and NO play important roles in apoptosis.On the other hand,the inhibition of UVB-induced apoptosis in the immortalized keratinocyte(HaCaT) cells by PCF was estimated using a DNA ladder.PCF treatment inhibited UVB-induced iNOS activation,as determined by RT-PCR,NO production,as determined by ESR,and up-regulated heat shock protein(HSP) 90 activation,as determined by Western blotting.Our results indicate that iNOS and NO are involved in UVB-induced apoptosis of HaCaT cells and the protective effect of PCF against UVB irradiation is exerted by suppressing the expression of iNOS,followed by inhibition of NO release and enhanced activation of HSP90.
基金the financial support from the National Natural Science Foundation of China(Nos.51973216,51873207,51803006,51833010,51673190 and 51520105004)the Science and Technology Development Program of Jilin Province(No.20190201068JC)+2 种基金the National Key Research and Development Program of China(No.2016YFC1100701)the Youth Talents Promotion Project of Jilin Province(No.181909)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2019005)。
文摘Polypeptides are one kind of promising biodegradable and biocompatible biomedical polymers with the structural units of various a-amino acids.Polypeptides were first polymerized by the ring-opening polymerization(ROP)of α-amino acid N-carboxyanhydrides(NCAs)by Leuchs and Hermann in 1906.In the past decades,several effective strategies,including the selection of initiators,the adjustment of reaction conditions,and the introduction of catalysts,have been reported to improve the controllability of the ROP of various a-amino acid NCAs to synthesize different polypeptides with precise chemical structures and low polydispersity indexes.In this Review,the strategies,mechanisms,challenges,and opportunities for controlled synthesis of polypeptides by the ROP of differentα-amino acid NCAs have been declared.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.21774031 and 21861162010)the National Key Research and Development Program of China(No.2016YFC1100401)+1 种基金Research Program of State Key Laboratory of Bioreactor Enginering,State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Donghua University,the Fundamental Research Funds for the Central Universities(Nos.22221818014 and 50321041917001)The authors also thank Research Center of Analysis and Test of East China University of Science and Technology for the help on the characterization.
文摘Polypeptides have been widely utilized in the fields of biomaterials and biomedicine.Ever since N-carboxyanhydride(NCA)was reported by Hermann Leuchs in 1906,ring-opening polymerization of NCAS has been extensively used to prepare polypeptides.Despite continuous innovations,it is still challenging to synthesize polypeptides in high molecular weight fficiently.To address this challenge,we developed KHMDS/NaHMDS initiated fast NCA polymerization that is also moisture tolerant,open-flask amenable and terminal tunable.This NCA polymerization was able to proceed in most common solvents and meet the solubility requirement of variable NCA monomers and corresponding polypeptides.KHMDS can initiate r benzy-L glutamate-N carboxyanhydride(BLG NCA)polymerization in a reaction rate 92 times faster than does hexylamine and 80 times faster than does triethylamine.This NCA polymerization also demonstrated easy and fast synthesis of gram-scale long chain polypeptides in an open flask.
基金a grant from the NationalNatural Science Foundation of China(No. 39870 76 3) and aFunding Program for New- Century Talent of the Ministry ofEducation of China
文摘To construct an eukaryotic expressing vector that expresses CH50, a recombinant CellⅠ HepⅡ bifunctional domain polypeptide of human fibronectin, and to investigate the chemotaxis to immune cells and the inhibitory effect on the growth of tumor by the expression of the plasmid in vivo , the plasmid was constructed by DNA recombination. Gene transfection was performed in vitro and in vivo . The expressed product was identified by Western blot. The chemotaxis after gene transfection in vivo was observed by histotomy and staining of muscle tissues. The inhibition of gene transfection on solid tumor was observed in mice. The results showed that plasmid pCH510 was constructed by the recombination of the 5′ terminal noncoding region and signal peptide coding region of human fibronectin cDNA and cDNA fragment coding CH50 polypeptide with a 3′ terminal noncoding region of human FN cDNA, and the insertion of the recombinated fragment into plasmid pcDNA3.1. After transfection with plasmid pCH510, NIH3T3 cells could produce CH50 polypeptide. The transfection of plasmid pCH510 by the injection in muscle of mouse could produce the effects of chemotaxis on immune cells and the inhibition on the growth of solid tumor. It is concluded that plasmid pCH510 can express in cells and in vivo in mouse. The expression of the plasmid in vivo has a chemotactic effect on immune cells and can inhibit the growth of solid tumor.
