氧化应激介导的Ras-ERK信号通路活化参与醛固酮诱导的肾小球系膜细胞增殖

目的 探讨氧化应激介导的Ras-胞外信号调节激酶(ERK1/2)信号通路活化在醛同酮( ALDO)诱导的系膜细胞增殖中的作用.方法 体外培养人肾小球系膜细胞,应用3H-胸腺嘧啶(3H-TdR)掺入法和细胞计数测定系膜细胞增殖;Western印迹检测Ki-RasA、c-Raf、MEK1/2和ERK1/2活化.结果 ALDO可显著促进系膜细胞增殖,抗氧化剂乙酰半胱氨酸(NAC)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)显著抑制ALDO诱导的系膜细胞增殖(均P＜ 0.01).ALDO刺激系膜细胞3h,活化的Ki-RasA、c-Raf、MEK1/2和ERK1/2表达显著增强,分别是对照组的4.05倍、3.62倍、4.52倍和3.40倍(均P＜0.01).抗氧化剂NAC几乎完全阻断ALDO诱导的Ki-RasA、c-Raf、MEK1/2和ERK 1/2活化(均P＜0.01).Ki-RasA siRNA可呈浓度依赖性降低系膜细胞Ki-RasA表达,并显著抑制ALDO诱导的Ki-RasA活化及系膜细胞增殖(P＜0.01).c-Raf抑制剂GW5074和MEK1/2抑制剂PD98059亦显著抑制ALDO诱导的系膜细胞增殖,其抑制率均达到65％(P＜0.01).Ki- RasA siRNA不能降低ALDO诱导的磷酸肌醇-3激酶( PI3K)磷酸化.联合应用PI3K抑制剂LY294002和MEKl/2抑制剂PD98059可完全阻断ALDO诱导的系膜细胞增殖(P＜0.01).结论 ALDO可通过氧化应激活化Ki-RasA-c-Raf-MEK-ERK信号通路.同时阻断ERK1/2和PI3K信号通路可完全抑制ALDO诱导的系膜细胞增殖.     

环磷酰胺静脉冲击疗法对频繁复发性肾病综合征患儿的临床疗效

目前 ,儿童难治性肾病的治疗仍是临床上较为棘手的问题 ,由于其病因、发病机制、病理类型不同而直接影响其疗效及预后。近年来有关大剂量环磷酰胺静脉冲击疗法 (ＣＴＸ ＰＴ)治疗小儿难治性肾病的报道较多 ,但结果不尽相同。我们的研究显示 ,ＣＴＸ ＰＴ治疗小儿难治性肾病综合征 (简称难治性肾病 )取得了较好效果[1,2 ] 。本文观察了ＣＴＸ ＰＴ对儿童频繁复发性肾病综合征 (ＦＲＮＳ)的预防效果以及远期转归 ,报道如下。1　对象和方法1.1　临床资料　 1991年 9月～ 1999年 12月接受ＣＴＸ ＰＴ治疗且具有完整资料的ＦＲＮＳ患儿 2 2例 ,临…     

核因子—kB反义寡核苷酸对系膜细胞炎症因子基因表达的影响

目的：探讨NF－kB反义寡核苷酸（oligodeoxynucleotide,ODN)对人肾小球系膜细胞炎症因子表达的影响，为利用NF－kB反义ODN治疗肾小球炎性病变奠定基础。方法：人工合成p65反义、正义及错配ODN并行全程硫代磷酸化修饰。应用核酸酶保护法观察阳离子脂质体介导的不同浓度的ODN（0．001、0．01、0．1、1、10μmol/L)对系膜细胞TNF－α、IL－1α、IL－1β、MCP－1、IL－8、TGF－β1 mRNA表达的影响，以正义ODN（10μmol/L)及错配ODN（10μmol/L)作为对照组。结果：正常培养状态下，系膜细胞可组成型表达TNF－α、IL－1β、IL－8和TGF－β1 mRNA，而不表达IL－1α和MCP－1 mRNA。细菌脂多糖（lipopolysaccharide,LPS)刺激后上述6种炎症因子表达显著上调。p65反义ODN可呈剂量依赖性地抑制LPS诱导的系膜细胞炎性细胞因子TNF－α，IL－α，IL－1β，MCP－1和IL－8的基因表达，而对TGF－β1无显著抑制作用；p65正义及错配ODN均不能抑制炎性细胞因子的表达。结论：p65反义ODN可明显抑制LPS诱导的肾小球系膜细胞炎性细胞因子的表达，提示NF－kB在肾小球疾病进展中起关键性调控作用，其反义ODN有可能应用于肾脏病变的实验性治疗之中。     

氧化低密度脂蛋白诱导Zucker肥胖大鼠肾小球系膜细胞AP-1活性的变化

目的 :研究氧化低密度脂蛋白 (oxidizedlow densitylipoprotein ,Ox LDL)对体外培养的Zucker大鼠肾小球系膜细胞 (glomerularmesangialcell,GMC)中核转录因子激活蛋白 1(activatorprotein 1,AP 1)活化的影响 ,以及观察Ox LDL诱导的AP 1活性的变化与Zucker大鼠鼠龄以及基因型的相关性。　 方法 :①采用Zucker肥胖大鼠 (3月龄和 10月龄 )及Zucker瘦型大鼠 (3月龄和 10月龄 )的 4种GMC株 (O3m,O10m,L3m,L10m)进行传代培养。②利用凝胶迁移率实验 (EMSA)和超迁移率实验检测不同浓度及不同时相Ox LDL对Zucker大鼠GMCAP 1活性的影响 ,以及AP 1二聚体中c jun和c fos成分的变化。　 结果 :①经Ox LDL诱导后 ,4个组GMC内AP 1活性均较对照组明显增强 (F =177 84 ,P <0 0 1) ;②随着Ox LDL刺激浓度增加和时间的延长 ,GMC内AP 1活性相应增强 ,5 0mg/L的Ox LDL刺激 8h时 ,AP 1活性强度达最高峰 ;③Ox LDL主要激活AP 1二聚体成分中的c jun ;④O10m组AP 1的活性显著高于O3m组 (P <0 0 1) ,L10m组AP 1的活性显著高于L3m组 (P <0 0 1) ,O10m组显著高于L10m组 (P <0 0 1) ,O3m组显著高于L3m组 (P <0 0 1)。　 结论 :Ox LDL可诱导Zucker大鼠GMC内AP 1活化 ,其活化方式呈时间和剂量依赖 ;活化强度与大鼠的基因型及鼠龄     

内质网应激与肾脏损伤

内质网( endoplasmic reticulum,ER)是真核细胞中一种重要的亚细胞器,其主要功能包括调节蛋白质的合成、折叠、运输及修饰.内质网功能易受环境损害的影响,例如缺氧、低糖、氧化应激和遗传突变都将导致内质网腔内蛋白质折叠异常.这些未折叠蛋门以及错误折叠蛋白的积聚引起内质网一系列功能的紊乱,称为内质网应激[1].内质网应激与多种疾病相关,如阿尔茨海默症、帕金森病、亨廷顿病、缺血再灌注损伤、糖尿病及动脉粥样硬化等.越来越多的证据提示,内质网应激在肾脏病理生理过程中亦发挥重要作用[2].本文就内质网应激与肾脏疾病的研究进展作一综述.一、内质网应激与未折叠蛋白反应发生内质网应激的细胞为能够恢复正确的蛋白折叠、阻止未折叠蛋白以及错误折叠蛋白的积聚,激活一项较为保守的适应性反应,称为未折叠蛋白反应( UPR).     

环磷酰胺静脉冲击联合泼尼松治疗儿童激素耐药性肾病综合征疗效分析

目的 了解大剂量环磷酰胺静脉冲击疗法（CTX－PT）治疗儿童激素耐药性肾病的近期疗效以及影响疗效的相关因素。方法 总结1991年9月－2000年3月接受CTX－PT治疗的激素耐药性肾病41例,并就其疾病类型、临床观察指标等与疗效的关系进行分析。结果 （1）本组CTX－PT完全缓解11例（26％）,部分缓解13例（31％）,总有效率58％。完全缓解的患儿尿蛋白转阴发生在第3、4、5个疗程的累计百分率分别为63％、82％和100％。（2）治疗前Scr水平较低者效果较好。CTX－PT疗效与疾病的临床、病理类型以及性别、发病年龄、病程、治疗前血清白蛋白、球蛋白、胆固醇、免疫球蛋白、24h尿蛋白排泄量等无关（P＞0．05）。（3）毒副作用：本组13例（31％）未见明显CTX毒副作用,28例（68％）出现不同程度的副作用。最常见的副作用是胃肠道反应,占51％,其次为轻度脱发（9％）,7％的患儿表现为血小板下降,血白细胞减少和反复感染均各为4％,肝功能异常及出血性膀胱炎各1例（2％）。这些毒副作用均为一过性,能自行缓解或通过对症处理后很快缓解。结论 CTX－PT治疗儿童激素耐药性肾病总有效率为58％;影响疗效的因素主要为Scr水平,疾病的临床、病理类型、性别、发病年龄、24h尿蛋白排泄量等与疗效无关。     

NADPH oxidase-derived reactive oxygen species involved in angiotensin Ⅱ-induced monocyte chemoattractant protein-1 expression in mesangial cells

Objective To investigate the origin of oxidative stress induced by angiotensin H (Ang Ⅱ ) in human mesangial cells and the role of reactive oxygen species ( ROS) in Ang Ⅱ -induced monocyte chemoattractant protein-1 (MCP-1) expression.Methods MCP-1 expression was determined by real time RT-PCR.ROS production was measured by DCFDA fluorescence.Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity was examined by lucigenin chemiluminescence.p47phox and p67phox translocation was assayed by Western blot.Twenty-four male mice were randomly divided into three groups; the control,the Ang Ⅱ infusion [ Ang Ⅱ 400 ng/(kg±min) ],and the apocynin treatment.Ang Ⅱ was infused by subcutaneously osmotic minipump for 14 days.Urinary albumin and 8-isoprostane excretion were measured by ELISA.Results In cultured human mesangial cells,Ang Ⅱ induced the MCP-1 expression in a dose-dependent manner with 3.56 fold increase as compared with the control.Ang Ⅱ increased intracellular ROS production as early as 3 min with the peak at 60 min and was in a time and dose-dependent.Incubation with different dosages of Ang Ⅱ ( 1μmol/L,10μmol/L,and 100μmol/L Ang Ⅱ ) for 60 min,ROS production increased at 1.82,2.92,and 4.08 folds respectively.Ang Ⅱ-induced ROS generation was sensitive to diphenyleneiodonium sulfate (DPI,10 μmol/L) and apocynin (500μmol/L) ,two structurally distinct NADPH oxidase inhibitors.In contrast,inhibitors of other oxidant- producing enzymes,including the mitochondrial complex I inhibitor rotenone,the xanthine oxidase inhibitor allopurinol,the cyclooxygenase inhibitor indomethacin,the lipoxygenase inhibitor nordihydroguiaretic acid,the cytochrome P450 oxygenase inhibitor ketoconazole and the nitric oxide synthase inhibitor G-nitro-L- arginine methyl ester were without an effect Ang Ⅱ -induced ROS generation was inhibited by the ATI antagonist losartan (10μmol/L) but not the AT2 antagonist PD123319 (10μmol/L).Ang Ⅱ treatment induced translocation of cytosolic of p47 and p67 to the membrane.The antioxidants almost abolished Ang Ⅱ -induced MCP-1 expression.Ang Ⅱ infusion increased urinary and p67 translocation by 2.69-,2.97-,and 2.67-fold,respectively.Conclusions NADPH oxidase-derived ROS is involved in Ang Ⅱ-induced MCP-1 expression.Inhibition of NADPH oxidase alleviates Ang Ⅱ -induced renal injury.     

氧化低密度脂蛋白诱导Zucker大鼠肾小球系膜细胞中NF-κB活性的变化

目的 :研究氧化低密度脂蛋白 (Ox LDL)对体外培养的Zucker大鼠肾小球系膜细胞 (GMC)核因子κB (NF κB)活性的影响以及NF κB的活性变化与大鼠鼠龄及基因型的相关性。方法 :(1)将 3月龄和 10月龄Zucker肥胖大鼠及Zucker瘦型大鼠的GMC(O3m、O10m,、L3m和L10m)进行传代培养。 (2 )采用电泳迁移率变动分析 (EMSA)和超迁移率实验 (GSA) ,检测不同浓度及不同时间相的Ox LDL对GMC中NF κB活性的影响及其亚单位p5 0和p6 5的变化。利用Westernblot检测Ox LDL刺激后NF κB的核转位。结果 :Ox LDL刺激后 ,O3m、O10m及L3m3组GMC中NF κB的活性均明显强于对照组 (P <0 .0 1) ;L10m组与对照组相比较无显著差异 (P >0 .0 5 )。随着Ox LDL浓度的增加和刺激时间的延长 ,GMC中NF κB活性也相应增强 ,5 0mg/L的Ox LDL刺激 4h时 ,NF κB的活性强度达最高峰。Ox LDL主要激活NF κB的p6 5及p5 0亚单位 ;各组NF κB的活性相比较 :O3m 组高于O10m组 ,O3m组高于L3m组及O10m组高于L10m组 (P均 <0 .0 1) ;L3m组NF κB的活性高于L10m组 (P <0 .0 5 ) .结论 :Ox LDL可诱导Zucker大鼠GMC中NF κB活化 ,且呈时间和浓度依赖性 ;活性强度与大鼠的基因型及鼠龄密切相关。Ox LDL诱导的NF κB活化在Zucker肥胖大鼠的早期肾损害中起着更为重     

NADPH oxidase-derived reactive oxygen species involved in angiotensin Ⅱ-induced monocyte chemoattractant protein-1 expression in mesangial cells

Objective To investigate the origin of oxidative stress induced by angiotensin H (Ang Ⅱ ) in human mesangial cells and the role of reactive oxygen species ( ROS) in Ang Ⅱ -induced monocyte chemoattractant protein-1 (MCP-1) expression.Methods MCP-1 expression was determined by real time RT-PCR.ROS production was measured by DCFDA fluorescence.Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity was examined by lucigenin chemiluminescence.p47phox and p67phox translocation was assayed by Western blot.Twenty-four male mice were randomly divided into three groups; the control,the Ang Ⅱ infusion [ Ang Ⅱ 400 ng/(kg±min) ],and the apocynin treatment.Ang Ⅱ was infused by subcutaneously osmotic minipump for 14 days.Urinary albumin and 8-isoprostane excretion were measured by ELISA.Results In cultured human mesangial cells,Ang Ⅱ induced the MCP-1 expression in a dose-dependent manner with 3.56 fold increase as compared with the control.Ang Ⅱ increased intracellular ROS production as early as 3 min with the peak at 60 min and was in a time and dose-dependent.Incubation with different dosages of Ang Ⅱ ( 1μmol/L,10μmol/L,and 100μmol/L Ang Ⅱ ) for 60 min,ROS production increased at 1.82,2.92,and 4.08 folds respectively.Ang Ⅱ-induced ROS generation was sensitive to diphenyleneiodonium sulfate (DPI,10 μmol/L) and apocynin (500μmol/L) ,two structurally distinct NADPH oxidase inhibitors.In contrast,inhibitors of other oxidant- producing enzymes,including the mitochondrial complex I inhibitor rotenone,the xanthine oxidase inhibitor allopurinol,the cyclooxygenase inhibitor indomethacin,the lipoxygenase inhibitor nordihydroguiaretic acid,the cytochrome P450 oxygenase inhibitor ketoconazole and the nitric oxide synthase inhibitor G-nitro-L- arginine methyl ester were without an effect Ang Ⅱ -induced ROS generation was inhibited by the ATI antagonist losartan (10μmol/L) but not the AT2 antagonist PD123319 (10μmol/L).Ang Ⅱ treatment induced translocation of cytosolic of p47 and p67 to the membrane.The antioxidants almost abolished Ang Ⅱ -induced MCP-1 expression.Ang Ⅱ infusion increased urinary and p67 translocation by 2.69-,2.97-,and 2.67-fold,respectively.Conclusions NADPH oxidase-derived ROS is involved in Ang Ⅱ-induced MCP-1 expression.Inhibition of NADPH oxidase alleviates Ang Ⅱ -induced renal injury.     

IgA肾病治疗的循证医学证据

IgA肾病（IgAN）又称系膜IgA肾病或Berger病，是一组具有共同免疫病理特征的临床综合征，其特点是肾组织免疫病理检查肾小球系膜区以IgA沉积为主，伴随着不同程度的局灶性或弥漫性系膜增生。临床表现多样化，但以发作性短暂性肉眼血尿和镜下血尿为主要表现，可伴或不伴蛋白尿。