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
The preparation of polypeptide materials in continuous flow reactors shows great potential with improved reproducibility and scalability.However,conventional polypeptide synthesis from the polymerization of N-carboxya...The preparation of polypeptide materials in continuous flow reactors shows great potential with improved reproducibility and scalability.However,conventional polypeptide synthesis from the polymerization of N-carboxyanhydride(NCA)is conducted at relatively slow rates,requiring long tubing or ending up with low-molecular-weight polymers.Inspired by recent advances in accelerated NCA polymerization,we report the crown-ether-catalyzed,rapid synthesis of polypeptide materials in cosolvents in flow reactors.The incorporation of low-polarity dichloromethane and the use of catalysts enabled fast conversion of monomers in 30 min,yielding well-defined polypeptides(up to 30 k Da)through a 20-cm tubing reactor.Additionally,random or block copolypeptides were efficiently prepared by incorporating a second NCA monomer.We believe that this work highlights the accelerated polymerization design in flow polymerization processes,offering the continuous production of polypeptide materials.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
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
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
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
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financially supported by the National Natural Science Foundation of China(No.22101194)Natural Science Foundation of Jiangsu Province(No.BK20210733)+3 种基金Suzhou Municipal Science and Technology Bureau(No.ZXL2021447)Collaborative Innovation Center of Suzhou Nano Science&Technologythe 111 ProjectJoint International Research Laboratory of Carbon-Based Functional Materials and Devices。
文摘The preparation of polypeptide materials in continuous flow reactors shows great potential with improved reproducibility and scalability.However,conventional polypeptide synthesis from the polymerization of N-carboxyanhydride(NCA)is conducted at relatively slow rates,requiring long tubing or ending up with low-molecular-weight polymers.Inspired by recent advances in accelerated NCA polymerization,we report the crown-ether-catalyzed,rapid synthesis of polypeptide materials in cosolvents in flow reactors.The incorporation of low-polarity dichloromethane and the use of catalysts enabled fast conversion of monomers in 30 min,yielding well-defined polypeptides(up to 30 k Da)through a 20-cm tubing reactor.Additionally,random or block copolypeptides were efficiently prepared by incorporating a second NCA monomer.We believe that this work highlights the accelerated polymerization design in flow polymerization processes,offering the continuous production of polypeptide materials.
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.
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.
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.
