The proliferation of glomerular mesangial cells （GMC） and secretion of the extracellular matrix （ECM） in rat with Thy-1 nephritis （Thy-lN） resembling human mesangioproliferative glomerulonephritis have been expl...The proliferation of glomerular mesangial cells （GMC） and secretion of the extracellular matrix （ECM） in rat with Thy-1 nephritis （Thy-lN） resembling human mesangioproliferative glomerulonephritis have been explored for many years; however, the molecular mechanisms of GMC proliferation and ECM production remain unclear. Our previous studies have demonstrated that the thrombospondin-1 （TSP-1） gene was involved in mediating rat GMC proliferation and ECM synthesis induced by sublytic C5b-9 in vitro. 111 the present study, the roles of the TSP-1 gene in GMC proliferation, ECM production, and urinary protein secretion in Thy-lN rats were determined by using TSP-1 small hairpin RNA, and the results revealed that silencing of the TSP-1 gene in rat renal tissues could diminish GMC proliferation （P 〈 0.01） and ECM secretion （P 〈 0.01） as well as urinary protein secretion （P 〈 0.05） in Thy-lN rats. Together, the current findings suggested that TSP-1 gene expression was required for GMC proliferation and ECM production in Thy-lN rats.展开更多
Objective To investigate the effects of rapamycin on cholesterol homeostasis of glomerular mesangial cells and the underlying mechanisms. Methods Intracellular cholesterol accumulation was measured by Oil Red O stain...Objective To investigate the effects of rapamycin on cholesterol homeostasis of glomerular mesangial cells and the underlying mechanisms. Methods Intracellular cholesterol accumulation was measured by Oil Red O staining and high performance liquid chromatography. The effects of rapamycin on interleukin-1β（1L-1β）-induced mRNA and protein changes of low-density lipoprotein receptor （LDLR） and ATP-binding cassette transporter Al （ABCAl） were assayed by quantitative real-time PCR and Western blot. Transient expressions of 3 types of mammalian target of rapamycin （mTOR）, including mTOR-WT （wild type）, mTOR-RR （rapamycin resistant, with kinase activity）, and mTOR-RR-KD （rapamycin resistant, without kinase activity）, were obtained by plasmid transfection. Results Rapamycin had no significant influence on intracellular cholesterol concentration trader normal condition, but it significantly decreased the intracellular cholesterol concentration in the presence of IL-1β. Rapamycin dose-dependently suppressed the increased expression of LDLR induced by IL-1β and up-regulated the suppressed expression of ABCAl caused by IL-1β Transient expression of 3 types of mTOR all reduced ABCAl mRNA expression significantly, which all could be overroded by rapamycin. Conclusions Rapamycin may contribute to the maintaining of glomerular mesangial cell intracellular cholesterol homeostasis under inflammatory state by both reducing cholesterol uptake and increasing cholesterol effiux. And the effect may be not completely mediiated by mTOR.展开更多
Objective To elucidate the renoprotective effect of resveratrol(RSV)on sphingosine kinase 1(SphK1)signaling pathway and expression of its downstream molecules including activator protein 1(AP-1)and transformation grow...Objective To elucidate the renoprotective effect of resveratrol(RSV)on sphingosine kinase 1(SphK1)signaling pathway and expression of its downstream molecules including activator protein 1(AP-1)and transformation growth factor-β1(TGF-β1)in lipopolysaccharide(LPS)-induced glomerular mesangial cells(GMCs).Methods The rat GMCs line(HBZY-1)were cultured and randomly divided into 5 groups,including control,LPS(100 ng/mL),and 5,10,20µmol/L RSV-treated groups.In addition,SphK1 inhibitor(SK-II)was used as positive control.GMCs were pretreated with RSV for 2 h and treated with LPS for another 24 h.GMCs proliferation was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT)assay.The proteins expression of SphK1,p-c-Jun and TGF-β1 in GMCs were detected by Western blot,and DNA-binding activity of AP-1 was performed by electrophoretic mobility shift assay(EMSA).The binding activity between RSV and SphK1 protein was detected by AutoDock Vina and visualized by Discovery Studio 2016.Results LPS could obviously stimulate GMCs proliferation,elevate SphK1,p-c-Jun and TGF-β1 expression levels and increase the DNA-binding activity of AP-1(P<0.05 or P<0.01),whereas these effects were significantly blocked by RSV pretreatment.It was also suggested that the effect of RSV was similar to SK-II(P>0.05).Moreover,RSV exhibited good binding affinity towards SphK1,with docking scores of−8.1 kcal/moL and formed hydrogen bonds with ASP-178 and LEU-268 in SphK1.Conclusion RSV inhibited LPS-induced GMCs proliferation and TGF-β1 expression,which may be independent of its hypoglycemic effect on preventing the development of mesangial cell fibrosis and closely related to the direct inhibition of SphK1 pathway.展开更多
The mechanism of injury on the human glomerular endothelial cells （ciGENC） induced by preeclampsia serum was investigated. Concentration of maternal serum sFlt-1 protein was detected by ELISA. Fluorescently-labeled ...The mechanism of injury on the human glomerular endothelial cells （ciGENC） induced by preeclampsia serum was investigated. Concentration of maternal serum sFlt-1 protein was detected by ELISA. Fluorescently-labeled bovine serum albumin infiltrating through lower chamber of Transwell was measured by multifunction microplate reader. Morphologic change of ciGENC was observed under inverted phase contrast microscope. The concentration of sflt-1 in preeclampsia groups was significantly increased as compared with control group （P〈0.01）. Permeability in preeclampsia groups was significantly increased as compared with control group （P〈0.01）. By contrast with severe preeclampsia group, the permeability of ciGENC monolayer in mild preeclampsia group was decreased significantly （P〈0.05）. Intervention of exogenous VEGF significantly decreased permeability of ciGENC in preeclampsia groups. It was concluded that sFlt-1 increased ciGENC permeability by damaging integrity of endothelial barrier function.展开更多
目的:对桑叶中1-脱氧野尻霉素的提取条件进行优化后研究其对高糖诱导的肾小球系膜细胞凋亡和炎性因子的影响。方法:建立1-脱氧野尻霉素的定量检测方法,探讨桑叶中1-脱氧野尻霉素的最佳提取条件。培养小鼠肾小球系膜(SV40 MES 13)细胞,...目的:对桑叶中1-脱氧野尻霉素的提取条件进行优化后研究其对高糖诱导的肾小球系膜细胞凋亡和炎性因子的影响。方法:建立1-脱氧野尻霉素的定量检测方法,探讨桑叶中1-脱氧野尻霉素的最佳提取条件。培养小鼠肾小球系膜(SV40 MES 13)细胞,并分为四组:正常对照组(PBS)、高糖组(30 mmoL/L葡萄糖)和1-脱氧野尻霉素组(2、50μM),给药结束后采用CCK-8法测定SV40 MES 13细胞的存活率,ELISA测定炎性因子单核细胞趋化蛋白1(Monocyte chemoattractant protein-1,MCP-1)、肿瘤坏死因子α(Tumor necrosis factor-alpha,TNF-α)和白细胞介素6(Interleukin-6,IL-6)的水平。最后用Western blotting法检测细胞增殖蛋白Cyclin D1和PCNA的表达水平。结果:桑叶中1-脱氧野尻霉素的提取条件最终优化为料液比1∶15 g/mL、pH值3.0和提取时间30 min。1-脱氧野尻霉素明显提高SV40 MES 13细胞的存活率,并下调炎性因子IL-6的表达水平,且高剂量的1-脱氧野尻霉素显著降低Cyclin D1和PCNA的表达。结论:选择合适的料液比、pH值和提取时间可优化桑叶中1-脱氧野尻霉素的提取工艺,此外,1-脱氧野尻霉素具有改善高糖诱导的肾小球系膜细胞凋亡的作用,其作用机制与调控炎性因子及相关增值蛋白的表达有关。展开更多
The apoptosis of glomerular mesangial cells(GMCs)is considered to be an important contributor to the initiation and development of rat Thy-1 nephritis(Thy-1N)and is accompanied by sublytic C5b-9 deposition.However,the...The apoptosis of glomerular mesangial cells(GMCs)is considered to be an important contributor to the initiation and development of rat Thy-1 nephritis(Thy-1N)and is accompanied by sublytic C5b-9 deposition.However,the mechanism by which sublytic C5b-9 triggers GMC apoptosis has not been elucidated.In this study,functional and histological examinations were performed on GMCs treated with sublytic C5b-9(in vitro)and renal tissues of Thy-1N rats(in vivo).The in vitro studies found that sublytic C5b-9 could trigger GMC apoptosis through upregulating Egr-1,ATF3,and Gadd45 expression.Egr-1-mediated post-transcriptional modulation of ATF3,Egr-1/ATF3-enhanced Gadd45 promoter activity,and p300-mediated ATF3 acetylation were all involved in GMC apoptosis.More importantly,the effective binding elements for Egr-1 and ATF3 to Gadd45β/γpromoters and the ATF3 acetylation site were identified.In vivo,silencing renal p300,Egr-1,ATF3,and Gadd45β/γsignificantly decreased GMC apoptosis,secondary GMC proliferation,and urinary protein secretion in Thy-1N rats.Together,these findings implicate that sublytic C5b-9-induced activation of Egr-1/p300–ATF3/Gadd45 axis plays a critical role in GMC apoptosis in Thy-1N rats.展开更多
Objective To study the effects of high glucose and transforming growth factor β1 (TGF β1) on the expression and function of glucose transporter 1 (GLUT1) in mouse mesangial cells Methods Cultured mouse mesang...Objective To study the effects of high glucose and transforming growth factor β1 (TGF β1) on the expression and function of glucose transporter 1 (GLUT1) in mouse mesangial cells Methods Cultured mouse mesangial cells were used The expression of GLUT1 mRNA was detected by Northern Blot; glucose uptake and its kinetics were determined with a 2 Deoxy [ 3H] D glucose uptake assay Results Mesangial cells exposed to enriched glucose medium (20?mmol/L) for 72 hours demonstrated a decrease in both GLUT1 mRNA and V max for uptake of the glucose analog, 2 deoxy D glucose (2DOG), as compared to mesangial cells cultured in physiologic glucose concentrations(5 5?mmol/L) In contrast, hypertonic mannitol had no effect on GLUT1 mRNA levels TGF β1 treatment for 10 hours stimulated 2DOG uptake, both in 5 5?mmol/L and 20?mmol/L glucose medium, by approximately 4 28 fold in a dose dependent manner (2?ng/ml maximum) Kinetic analysis of 2DOG uptake revealed an increase in V max and a decrease in K m in the presence of TGF β1 TGF β1 also up regulated the expression of GLUT1 mRNA in mesangial cells The addition of anti TGF β neutralizing antibody (30?μg/ml) in mesangial cells cultured in enriched glucose medium (20?mmol/L) led to a 40% decrease in 2DOG uptake Conclusions The expression of GLUT1 can be suppressed by exposure of mesangial cells to high glucose medium, which may serve as a protective mechanism against possible adverse effects of excessive glucose flux into cells TGF β1 stimulates glucose uptake by enhancing the expression and function of GLUT1 in mesangial cells This effect is independent of the glucose milieu in the cultured medium展开更多
目的观察过氧化脂质体增殖激活受体γ(PPARγ)激动剂噻唑烷二酮类化合物(罗格列酮,RGZ)对高糖刺激大鼠肾小球系膜细胞细胞间粘附分子-1(ICAM-1)和β1整合素表达的影响,了解PPARγ与粘附分子的关系。方法体外培养大鼠HBZY-1肾小球系膜细...目的观察过氧化脂质体增殖激活受体γ(PPARγ)激动剂噻唑烷二酮类化合物(罗格列酮,RGZ)对高糖刺激大鼠肾小球系膜细胞细胞间粘附分子-1(ICAM-1)和β1整合素表达的影响,了解PPARγ与粘附分子的关系。方法体外培养大鼠HBZY-1肾小球系膜细胞,分为9组:正常糖组,高糖组,甘露醇组,正常糖及高糖加1、5、10μm o l/L罗格列酮组。干预作用24 h后采用细胞免疫组化染色检测ICAM-1表达,间接免疫荧光染色及流式细胞仪检测β1整合素表达。结果高糖刺激使系膜细胞ICAM-1、β1整合素表达增加,且不依赖于渗透压。罗格列酮能够抑制正常糖和高糖诱导的系膜细胞ICAM-1、β1整合素表达;高糖组罗格列酮抑制作用更强,且呈剂量依赖性。β1整合素与ICAM-1呈正相关。结论粘附分子参与了糖尿病肾病(DN)发病机制,PPARγ激动剂罗格列酮可能通过对高糖刺激粘附分子表达的抑制效应而影响DN系膜扩张和肾小球硬化过程。展开更多
目的观察高糖刺激的大鼠肾小球系膜细胞基质金属蛋白酶-2(MMP-2)及其组织抑制物-2(TIMP-2)、膜型基质金属蛋白酶-1(MT1-MMP)和结缔组织生长因子(CTGF)的动态变化以探讨糖尿病肾病(DN)的发病机制。方法体外培养的大鼠HBZY-1肾小球系膜细...目的观察高糖刺激的大鼠肾小球系膜细胞基质金属蛋白酶-2(MMP-2)及其组织抑制物-2(TIMP-2)、膜型基质金属蛋白酶-1(MT1-MMP)和结缔组织生长因子(CTGF)的动态变化以探讨糖尿病肾病(DN)的发病机制。方法体外培养的大鼠HBZY-1肾小球系膜细胞分为低糖(5.5mmol/L葡萄糖)组、高糖(30mmol/L葡萄糖)组和渗透压对照(5.5mmol/L葡萄糖+24.5mmol/L甘露醇)组,24、48、72、96h后采用RT-PCR及Western blotting法分别检测MMP-2、TIMP-2、MT1-MMP及CTGF的mRNA及蛋白表达情况,酶联免疫吸附法(ELISA)检测培养上清中Ⅳ型胶原的含量。结果 Western blotting结果显示,与低糖组相比,高糖组MMP-2的表达在24h时略有升高,较低糖组增加10%±4%(P<0.05),至48h时则较低糖组减少42%±2%,其后随时间延长表达持续降低,至96h时较低糖组减少78%±2%;MT1-MMP表达在24h开始下降并随时间呈下降趋势,与低糖组相比较,在刺激的24h,高糖组MT1-MMP表达下降了29%±3%,随后持续下降,至96h则下降了78%±9%(P<0.01)。高糖组各时间点TIMP-2和CTGF表达均较低糖组增高,其中CTGF的表达在高糖刺激的24h即显著增高,为低糖组的201%±24%,随后持续增高,至培养96h为低糖组的484%±51%(P<0.01);TIMP-2的表达在24h时较低糖组增加55%±3%,且随时间延长呈增高趋势(P<0.01)。MMP-2、TIMP-2、MT1-MMP和CTGF的mRNA表达与相应蛋白的表达趋势基本一致。与低糖组相比,高糖组细胞上清中的Ⅳ型胶原于24h即有增加,且持续增高至96h(P<0.05)。低糖组和渗透压对照组组内、组间的各指标差异均无统计学意义。结论尽管高糖刺激早期可小幅诱导MMP-2的表达增强,但长期高糖刺激则可抑制MMP-2和MT1-MMP的表达及活化,同时促进系膜细胞TIMP-2和CTGF的表达。DN中肾小球细胞外基质的积聚可能是由于上述细胞因子和蛋白酶引起细胞外基质代谢失衡所致。展开更多
基金supported by grants from National Natural Science Foundations of China (No. 31000396, and No.81072402)grants from Natural Science Foundations of Jiangsu Province in China (No. BK2009417, No. 10KJB310006, and No. 09hx43)
文摘The proliferation of glomerular mesangial cells （GMC） and secretion of the extracellular matrix （ECM） in rat with Thy-1 nephritis （Thy-lN） resembling human mesangioproliferative glomerulonephritis have been explored for many years; however, the molecular mechanisms of GMC proliferation and ECM production remain unclear. Our previous studies have demonstrated that the thrombospondin-1 （TSP-1） gene was involved in mediating rat GMC proliferation and ECM synthesis induced by sublytic C5b-9 in vitro. 111 the present study, the roles of the TSP-1 gene in GMC proliferation, ECM production, and urinary protein secretion in Thy-lN rats were determined by using TSP-1 small hairpin RNA, and the results revealed that silencing of the TSP-1 gene in rat renal tissues could diminish GMC proliferation （P 〈 0.01） and ECM secretion （P 〈 0.01） as well as urinary protein secretion （P 〈 0.05） in Thy-lN rats. Together, the current findings suggested that TSP-1 gene expression was required for GMC proliferation and ECM production in Thy-lN rats.
文摘Objective To investigate the effects of rapamycin on cholesterol homeostasis of glomerular mesangial cells and the underlying mechanisms. Methods Intracellular cholesterol accumulation was measured by Oil Red O staining and high performance liquid chromatography. The effects of rapamycin on interleukin-1β（1L-1β）-induced mRNA and protein changes of low-density lipoprotein receptor （LDLR） and ATP-binding cassette transporter Al （ABCAl） were assayed by quantitative real-time PCR and Western blot. Transient expressions of 3 types of mammalian target of rapamycin （mTOR）, including mTOR-WT （wild type）, mTOR-RR （rapamycin resistant, with kinase activity）, and mTOR-RR-KD （rapamycin resistant, without kinase activity）, were obtained by plasmid transfection. Results Rapamycin had no significant influence on intracellular cholesterol concentration trader normal condition, but it significantly decreased the intracellular cholesterol concentration in the presence of IL-1β. Rapamycin dose-dependently suppressed the increased expression of LDLR induced by IL-1β and up-regulated the suppressed expression of ABCAl caused by IL-1β Transient expression of 3 types of mTOR all reduced ABCAl mRNA expression significantly, which all could be overroded by rapamycin. Conclusions Rapamycin may contribute to the maintaining of glomerular mesangial cell intracellular cholesterol homeostasis under inflammatory state by both reducing cholesterol uptake and increasing cholesterol effiux. And the effect may be not completely mediiated by mTOR.
基金Supported by the National Natural Science Foundation of China(No.81603355,81900745)。
文摘Objective To elucidate the renoprotective effect of resveratrol(RSV)on sphingosine kinase 1(SphK1)signaling pathway and expression of its downstream molecules including activator protein 1(AP-1)and transformation growth factor-β1(TGF-β1)in lipopolysaccharide(LPS)-induced glomerular mesangial cells(GMCs).Methods The rat GMCs line(HBZY-1)were cultured and randomly divided into 5 groups,including control,LPS(100 ng/mL),and 5,10,20µmol/L RSV-treated groups.In addition,SphK1 inhibitor(SK-II)was used as positive control.GMCs were pretreated with RSV for 2 h and treated with LPS for another 24 h.GMCs proliferation was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT)assay.The proteins expression of SphK1,p-c-Jun and TGF-β1 in GMCs were detected by Western blot,and DNA-binding activity of AP-1 was performed by electrophoretic mobility shift assay(EMSA).The binding activity between RSV and SphK1 protein was detected by AutoDock Vina and visualized by Discovery Studio 2016.Results LPS could obviously stimulate GMCs proliferation,elevate SphK1,p-c-Jun and TGF-β1 expression levels and increase the DNA-binding activity of AP-1(P<0.05 or P<0.01),whereas these effects were significantly blocked by RSV pretreatment.It was also suggested that the effect of RSV was similar to SK-II(P>0.05).Moreover,RSV exhibited good binding affinity towards SphK1,with docking scores of−8.1 kcal/moL and formed hydrogen bonds with ASP-178 and LEU-268 in SphK1.Conclusion RSV inhibited LPS-induced GMCs proliferation and TGF-β1 expression,which may be independent of its hypoglycemic effect on preventing the development of mesangial cell fibrosis and closely related to the direct inhibition of SphK1 pathway.
基金supported by a grant from Doctoral Program of Higher Education Research Fund Project (No.2010014 2110074)
文摘The mechanism of injury on the human glomerular endothelial cells （ciGENC） induced by preeclampsia serum was investigated. Concentration of maternal serum sFlt-1 protein was detected by ELISA. Fluorescently-labeled bovine serum albumin infiltrating through lower chamber of Transwell was measured by multifunction microplate reader. Morphologic change of ciGENC was observed under inverted phase contrast microscope. The concentration of sflt-1 in preeclampsia groups was significantly increased as compared with control group （P〈0.01）. Permeability in preeclampsia groups was significantly increased as compared with control group （P〈0.01）. By contrast with severe preeclampsia group, the permeability of ciGENC monolayer in mild preeclampsia group was decreased significantly （P〈0.05）. Intervention of exogenous VEGF significantly decreased permeability of ciGENC in preeclampsia groups. It was concluded that sFlt-1 increased ciGENC permeability by damaging integrity of endothelial barrier function.
基金supported by grants from the National Natural Science Foundations of China(81273333,81471626,and 31470853)the Natural Science Foundation of Jiangsu Higher Education Institutions of China(14KJB310006)supported by Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions.
文摘The apoptosis of glomerular mesangial cells(GMCs)is considered to be an important contributor to the initiation and development of rat Thy-1 nephritis(Thy-1N)and is accompanied by sublytic C5b-9 deposition.However,the mechanism by which sublytic C5b-9 triggers GMC apoptosis has not been elucidated.In this study,functional and histological examinations were performed on GMCs treated with sublytic C5b-9(in vitro)and renal tissues of Thy-1N rats(in vivo).The in vitro studies found that sublytic C5b-9 could trigger GMC apoptosis through upregulating Egr-1,ATF3,and Gadd45 expression.Egr-1-mediated post-transcriptional modulation of ATF3,Egr-1/ATF3-enhanced Gadd45 promoter activity,and p300-mediated ATF3 acetylation were all involved in GMC apoptosis.More importantly,the effective binding elements for Egr-1 and ATF3 to Gadd45β/γpromoters and the ATF3 acetylation site were identified.In vivo,silencing renal p300,Egr-1,ATF3,and Gadd45β/γsignificantly decreased GMC apoptosis,secondary GMC proliferation,and urinary protein secretion in Thy-1N rats.Together,these findings implicate that sublytic C5b-9-induced activation of Egr-1/p300–ATF3/Gadd45 axis plays a critical role in GMC apoptosis in Thy-1N rats.
文摘Objective To study the effects of high glucose and transforming growth factor β1 (TGF β1) on the expression and function of glucose transporter 1 (GLUT1) in mouse mesangial cells Methods Cultured mouse mesangial cells were used The expression of GLUT1 mRNA was detected by Northern Blot; glucose uptake and its kinetics were determined with a 2 Deoxy [ 3H] D glucose uptake assay Results Mesangial cells exposed to enriched glucose medium (20?mmol/L) for 72 hours demonstrated a decrease in both GLUT1 mRNA and V max for uptake of the glucose analog, 2 deoxy D glucose (2DOG), as compared to mesangial cells cultured in physiologic glucose concentrations(5 5?mmol/L) In contrast, hypertonic mannitol had no effect on GLUT1 mRNA levels TGF β1 treatment for 10 hours stimulated 2DOG uptake, both in 5 5?mmol/L and 20?mmol/L glucose medium, by approximately 4 28 fold in a dose dependent manner (2?ng/ml maximum) Kinetic analysis of 2DOG uptake revealed an increase in V max and a decrease in K m in the presence of TGF β1 TGF β1 also up regulated the expression of GLUT1 mRNA in mesangial cells The addition of anti TGF β neutralizing antibody (30?μg/ml) in mesangial cells cultured in enriched glucose medium (20?mmol/L) led to a 40% decrease in 2DOG uptake Conclusions The expression of GLUT1 can be suppressed by exposure of mesangial cells to high glucose medium, which may serve as a protective mechanism against possible adverse effects of excessive glucose flux into cells TGF β1 stimulates glucose uptake by enhancing the expression and function of GLUT1 in mesangial cells This effect is independent of the glucose milieu in the cultured medium
文摘目的观察过氧化脂质体增殖激活受体γ(PPARγ)激动剂噻唑烷二酮类化合物(罗格列酮,RGZ)对高糖刺激大鼠肾小球系膜细胞细胞间粘附分子-1(ICAM-1)和β1整合素表达的影响,了解PPARγ与粘附分子的关系。方法体外培养大鼠HBZY-1肾小球系膜细胞,分为9组:正常糖组,高糖组,甘露醇组,正常糖及高糖加1、5、10μm o l/L罗格列酮组。干预作用24 h后采用细胞免疫组化染色检测ICAM-1表达,间接免疫荧光染色及流式细胞仪检测β1整合素表达。结果高糖刺激使系膜细胞ICAM-1、β1整合素表达增加,且不依赖于渗透压。罗格列酮能够抑制正常糖和高糖诱导的系膜细胞ICAM-1、β1整合素表达;高糖组罗格列酮抑制作用更强,且呈剂量依赖性。β1整合素与ICAM-1呈正相关。结论粘附分子参与了糖尿病肾病(DN)发病机制,PPARγ激动剂罗格列酮可能通过对高糖刺激粘附分子表达的抑制效应而影响DN系膜扩张和肾小球硬化过程。
文摘目的观察高糖刺激的大鼠肾小球系膜细胞基质金属蛋白酶-2(MMP-2)及其组织抑制物-2(TIMP-2)、膜型基质金属蛋白酶-1(MT1-MMP)和结缔组织生长因子(CTGF)的动态变化以探讨糖尿病肾病(DN)的发病机制。方法体外培养的大鼠HBZY-1肾小球系膜细胞分为低糖(5.5mmol/L葡萄糖)组、高糖(30mmol/L葡萄糖)组和渗透压对照(5.5mmol/L葡萄糖+24.5mmol/L甘露醇)组,24、48、72、96h后采用RT-PCR及Western blotting法分别检测MMP-2、TIMP-2、MT1-MMP及CTGF的mRNA及蛋白表达情况,酶联免疫吸附法(ELISA)检测培养上清中Ⅳ型胶原的含量。结果 Western blotting结果显示,与低糖组相比,高糖组MMP-2的表达在24h时略有升高,较低糖组增加10%±4%(P<0.05),至48h时则较低糖组减少42%±2%,其后随时间延长表达持续降低,至96h时较低糖组减少78%±2%;MT1-MMP表达在24h开始下降并随时间呈下降趋势,与低糖组相比较,在刺激的24h,高糖组MT1-MMP表达下降了29%±3%,随后持续下降,至96h则下降了78%±9%(P<0.01)。高糖组各时间点TIMP-2和CTGF表达均较低糖组增高,其中CTGF的表达在高糖刺激的24h即显著增高,为低糖组的201%±24%,随后持续增高,至培养96h为低糖组的484%±51%(P<0.01);TIMP-2的表达在24h时较低糖组增加55%±3%,且随时间延长呈增高趋势(P<0.01)。MMP-2、TIMP-2、MT1-MMP和CTGF的mRNA表达与相应蛋白的表达趋势基本一致。与低糖组相比,高糖组细胞上清中的Ⅳ型胶原于24h即有增加,且持续增高至96h(P<0.05)。低糖组和渗透压对照组组内、组间的各指标差异均无统计学意义。结论尽管高糖刺激早期可小幅诱导MMP-2的表达增强,但长期高糖刺激则可抑制MMP-2和MT1-MMP的表达及活化,同时促进系膜细胞TIMP-2和CTGF的表达。DN中肾小球细胞外基质的积聚可能是由于上述细胞因子和蛋白酶引起细胞外基质代谢失衡所致。
