NGAL对大鼠肾脏缺血再灌注损伤时肾小管上皮细胞凋亡的保护作用

目的探讨中性粒细胞明胶酶相关脂质运载蛋白（neutrophil gelatinase associated lipocalin,NGAL）对大鼠肾脏缺血再灌注损伤肾小管上皮细胞凋亡及凋亡蛋白fas,bcl-2表达的影响。方法建立大鼠肾脏缺血再灌注损伤模型,用HE染色观察肾组织病理变化情况;TUNEL法检测肾小管上皮细胞凋亡;免疫组织化学方法检测fas,bcl-2蛋白表达,并利用图像分析系统测量阳性表达率进行定量分析。结果①缺血再灌注模型组肾小管上皮细胞凋亡数为（20．8±3．7）个／高倍视野,NGAL组为（8．6±3．4）个／高倍视野,2组差异有统计学意义（P〈0．05）。②NGAL组较缺血再灌注模型组fas阳性表达率下降,差异有统计学意义（P〈0．05）;bcl-2阳性表达率增强,差异有统计学意义（P〈0．05）。结论NGAL对大鼠缺血再灌注损伤的肾小管上皮细胞有保护作用,其作用可能与减少细胞凋亡、改变凋亡蛋白的表达有关系。     

霉酚酸酯抑制大鼠肾脏缺血再灌注损伤诱导的肾小管上皮细胞凋亡

目的研究霉酚酸酯(MMF)对大鼠肾脏缺血再灌注(I／R)损伤诱导的肾小管上皮细胞凋亡的保护作用及机制。方法Wistar大鼠随机分为假手术组、I／R组、I／R MMF组。双侧肾动脉夹闭30min再灌注18h制作动物模型。观察肾功能及肾脏病理改变。以原位末端标记(TUNEL)及DNA电泳方法检测肾小管上皮细胞凋亡情况。RT—PCR法测定肾组织肿瘤坏死因子α(TNF—α)mRNA表达。Western印迹法测定肾组织半胱氨酸天冬氨酸蛋白酶(caspase)3、8蛋白表达。结果肾脏缺血30min再灌注18h后，大鼠肾功能明显减退，肾脏病理改变明显，大量肾小管上皮细胞凋亡，肾组织中TNF—α mRNA表达及caspase-3、-8蛋白表达显著增加。MMF能显著改善肾功能和肾脏组织病理学改变，减轻肾小管上皮细胞凋亡，显著下调TNF—α mRNA表达及caspaae-3、-8蛋白表达。结论MMF能抑制肾脏I／R损伤诱导的肾小管上皮细胞凋亡．保护肾功能，其作用至少部分是通过减少肾组织局部TNF-α含量，从而影响了caspase依赖的外源性凋亡途径实现的。     

阿魏酸钠抑制缺血性急性肾衰竭肾小管上皮细胞凋亡

目的：探讨阿魏酸钠对缺血性急性肾衰竭大鼠肾脏小管上皮细胞凋亡的影响及机制。方法：将雄性SD大鼠随机分为假手术组、缺血再灌注组、阿魏酸钠冶疗组、SOD冶疗对照组。观察肾组织病理改变；免疫组化、RT—PCR检测Bax，Bcl-2的表达；采用原位DNAg-断末端标记法（TUNEL）检测肾组织细胞凋亡。结果：大鼠肾脏缺血45min再灌注24h，大鼠肾功能损害明显，肾脏组织病理学改变明显，肾小管上皮细胞凋亡明显，肾组织Bax蛋白、mRNA的表达上调，Bcl-2蛋白、mRNA的表达下调。应用阿魏酸钠干预后。改变与上述相反。结论：在缺血性急性肾衰竭中，阿魏酸钠减轻肾脏缺血再灌注桶伤．减轻肾脏细胞凋亡．缓解肾功能桶害．奠作用至少部分通过调控凋亡相关基因Bcl-2家族基因的表达。     

替普瑞酮对大鼠肾脏缺血再灌注损伤的保护作用

目的 探讨替普瑞酮对肾脏缺血再灌注损伤的保护作用和可能机制。 方法 应用替普瑞酮(400 mg/kg)诱导雄性SD大鼠肾脏高表达热休克蛋白72（HSP72）。以钳夹大鼠左肾蒂45 min后，松开血管夹并切除右肾，建立大鼠缺血再灌注肾脏损伤模型。假手术组为打开腹腔，分离肾血管周围组织，但不钳夹血管。模型建立后24 h处死大鼠，留取血清测血肌酐（Scr）和尿素氮（BUN）。肾组织石蜡切片行PAS染色，以损伤肾小管所占百分比评分法评估肾组织肾小管损伤程度。TUNEL法检测缺血再灌注损伤时肾脏细胞凋亡的发生情况。Western印迹检测X连锁凋亡抑制蛋白（XIAP）的水平。 结果 缺血再灌注损伤可导致急性肾衰竭，表现为血Scr、BUN明显升高（P < 0.01）；PAS染色显示外髓部有大片肾小管坏死，甚至出现基底膜裸露；TUNEL染色中肾小管上皮细胞TUNEL阳性细胞数明显增多（P < 0.01）；Western印迹结果显示，肾组织XIAP蛋白水平明显降低（P < 0.01）。替普瑞酮处理后，肾组织HSP72表达水平明显增高（P < 0.01）；缺血再灌注所致的肾脏损伤明显改善，包括肾小管的损伤、细胞凋亡以及肾功能。此外，替普瑞酮可稳定肾组织XIAP的蛋白水平（P < 0.05）。 结论 替普瑞酮可诱导肾脏高表达HSP72。替普瑞酮可能通过减少肾脏XIAP蛋白的降解，抑制细胞凋亡，减轻缺血再灌注的肾脏损伤。     

党参皂甙减轻大鼠移植肾缺血再灌注损伤中细胞凋亡的作用及其机制

目的 探讨党参提取物皂甙减轻移植肾缺血再灌注损伤中细胞凋亡的作用及其机制.方法 将雌、雄各半SD大鼠随机分成三组,每组20只,即假手术组、缺血再灌注组和皂甙干预组.假手术组不进行肾移植,仅切除右肾,游离左肾动静脉,暴露左肾1 h后关闭腹腔.缺血再灌注组和皂甙干预组建立大鼠移植肾缺血再灌注损伤模型.皂甙干预组分别于肾移植前48、24和0.5 h经腹腔注入皂甙溶液(每千克体重80 mg).移植肾再灌注后24 h,取大鼠外周血和移植肾组织待测.检测各组血尿素氮(BUN)和肌酐(Cr)水平;采用脱氧核糖核苷酸末端转移酶介导的缺口末端标记(TUNEL)法检测各组肾组织原位细胞凋亡指数(AI);采用逆转录聚合酶链反应(RT-PCR)检测与细胞凋亡有关的基因Bcl-2和Bax mRNA在各组肾组织中的相对表达量.结果 与假手术组相比,缺血再灌注组和皂甙干预组血BUN和Cr水平都显著升高(P＜0.05);移植肾细胞凋亡指数也显著增高(P＜0.05);移植肾组织中Bcl-2 mRNA表达显著降低,Bax mRNA表达显著增高(P＜0.05).与缺血再灌注组比较,皂甙干预组血BUN和Cr值明显下降(P＜0.05);移植肾细胞凋亡指数明显下降(P＜0.05);移植肾组织中Bcl-2 mRNA表达显著增加,Bax mRNA表达明显下降(P＜0.05).结论 党参皂甙在移植肾缺血再灌注损伤中能显著减轻细胞凋亡.其机制可能是通过对Bcl-2基因表达的上调和对Bax基因表达的下调,从而抑制细胞的凋亡.     

姜黄素预处理对大鼠缺血再灌注肾小管上皮细胞凋亡的影响

目的：建立大鼠。肾脏缺血再灌注损伤（IRI）模型,观察姜黄素预处理对大鼠肾脏缺血再灌注肾小管上皮细胞凋亡的影响。方法：36只SD雄性大鼠随机分为3组,分别为假手术（Sham）组、肾脏缺血再灌注模型（IR）组、姜黄素预处理（CUR）组,每组12只。CUR组在缺血前2h给予姜黄素100mg／kg剂量溶于0．1％二甲基亚砜1ml中,注入腹腔。24小时后沿原切口进入,切除左。肾。肾组织用4％多聚甲醛固定24h,常规石蜡包埋切片。采用TUNEL法检测各组缺血肾小管上皮细胞凋亡。结果：与Sham组相比,IR组肾小管上皮细胞凋亡明显增加。与IR组比较,CUR组肾小管上皮细胞凋亡减少（P＜0．05）。结论：姜黄素预处理可减轻肾脏IRI的肾小管上皮细胞凋亡。     

乌司他丁对大鼠肾缺血/再灌注损伤的保护作用

目的探讨乌司他丁对大鼠肾缺血/再灌注(I/R)损伤的作用及其机制.方法雄性SD大鼠75只,随机分为三组假手术对照组(C组)、肾I/R组(I组)、乌司他丁组(U组),每组25只.I组和U组大鼠夹闭双侧肾蒂45min后重新开放肾脏血供,制作肾脏I/R模型,C组不夹闭双侧肾蒂.U组缺血前30min及再灌注开始时静脉注射乌司他丁1.25万单位,I组分别静脉注射生理盐水1ml.各组在再灌注后0、2、6、12、24h时取标本,测定血尿素氮(BUN)和血肌酐(Cr)浓度,并制备肾脏病理切片,采用免疫组化方法测定热休克蛋白70(HSP70)和bcl-2蛋白的表达.结果与I组比较,C组在再灌注后各时点血清BUN和Cr浓度均降低(P＜0.05),U组在再灌注后12、24h时血清BUN和Cr浓度也降低(P＜0.05).C组肾脏未发现明显的形态学改变;I组近曲小管上皮细胞空泡变性和坏死,肾小管腔扩张,内可见管型和坏死脱落细胞,可见管周血管明显扩张淤血;U组近曲小管上皮细胞肿胀、颗粒变性,罕见管型,管周稍有淤血.与I组比较,C组在再灌注后0、6、12、24h时Paller评分降低(P＜0.05),U组在再灌注后0、6、24h时Paller评分也降低(P＜0.05),C组再灌注后12、24h时HSP70表达降低(P＜0.05),U组在再灌注后6、24h时bcl-2蛋白表达增强(P＜0.05).结论乌司他丁对肾脏I/R损伤有保护作用,其机理可能与上调肾脏bcl-2蛋白表达有关.     

中介素减轻大鼠肾脏缺血再灌注损伤

目的 探讨中介素(IMD)对大鼠肾脏缺血再灌注损伤(IRI)的影响,及其过程中一氧化氮合酶(NOS)的作用和机制.方法 将健康雄性Wistar大鼠分为4组:假手术组,行右肾切除术,1周后单纯分离左侧肾蒂及肾动脉,而不夹闭肾动脉；肾脏缺血再灌注(IR)组,行右肾切除术,1周后行左肾缺血再灌注手术；IMD基因转染组,右肾切除后左肾行超声微泡介导的IMD-pCDNA3.1(+)质粒转染术,饲养1周,再行左肾缺血再灌注手术；空质粒转染组,右肾切除后左肾行超声微泡介导的pCDNA3.1(+)质粒转染术,饲养1周,再行左肾缺血再灌注手术.大鼠于缺血再灌注术后24 h处死,用免疫组织化学方法检测肾组织IMD表达,取肾组织进行病理学观察,取血清测定尿素氮(BUN)和肌酐(Cr)浓度,检测肾组织中内皮型NOS(eNOS)、诱导型NOS(iNOS)以及神经型NOS(nNOS) mRNA及其蛋白的表达.结果 假手术组大鼠肾组织中IMD位于肾小管及间质细胞胞浆内,其表达灰度值为66±35;肾脏IR组大鼠肾小管上皮细胞和间质中IMD表达灰度值为176±48,高于假手术组(P＜0.01)；IMD基因转染组肾组织中IMD表达灰度值为262±68,高于肾脏IR组(P＜0.01)；空质粒转染组IMD表达灰度值为180±51,和肾脏IR组间表达的差异无统计学意义(P＞0.05).与肾脏IR组相比较,IMD基因转染组大鼠肾脏组织病理损伤程度较轻,血清BUN和Cr较低(P＜0.05),eNOS mRNA及eNOS表达升高(P＜0.05),iNOS mRNA及iNOS表达降低(P＜0.05),而两组间nNOSmRNA及nNOS表达的差异无统计学意义(P＞0.05).结论 中介素可能通过促进eNOS表达、抑制iNOS表达从而减轻大鼠肾脏IRI.     

瑞芬太尼对大鼠肾缺血再灌注时细胞凋亡的影响

目的 评价瑞芬太尼对大鼠肾缺血再灌注时细胞凋亡的影响.方法 健康成年雄性SD大鼠75只,体重220～ 250 g,采用随机数字表法,将其分为3组(n=25)∶假手术组(S组)、肾缺血再灌注组(I/R组)和瑞芬太尼组(R组).I/R组和R组采用夹闭双侧肾动脉45 min时恢复灌注法建立肾缺血再灌注损伤模型.R组于缺血前15 min至再灌注30 min经尾静脉输注瑞芬太尼1.0μg· kg-1·min-1,S组和I/R组给予等容量生理盐水.于缺血前15 min(T0)、再灌注3 h(T1)、6 h(T2)、12h(T3)及24 h(T4)时取肾组织标本.采用流式细胞术检测肾细胞凋亡率及Bax、Bcl-2蛋白表达,采用RT-PCR检测Bax和Bcl-2的mRNA表达,计算Bcl-2/Bax蛋白及mRNA表达比值,采用Paller法行肾小管损伤评分.结果 与S组比较,I/R组和R组T1-4时肾小管损伤评分和肾细胞凋亡率升高,Bcl-2/Bax蛋白及mRNA表达比值T12时升高,T3,4时降低(P＜0.01);与I/R组比较,R组T1-4时肾小管损伤评分和肾细胞凋亡率降低,Bcl-2/Bax蛋白及mRNA表达比值升高(P＜0.05或0.01);与T0时比较,I/R组和R组T1-4时肾小管损伤评分和肾细胞凋亡率升高,Bcl-2/Bax蛋白及mRNA表达比值T1,2时升高,T3,4时降低(P＜0.01).结论 瑞芬太尼减轻大鼠肾缺血再灌注损伤的机制与其调节Bcl-2/Bax蛋白表达,抑制肾组织细胞凋亡有关.     

山莨菪碱对过度训练大鼠肾小管上皮细胞Toll样受体4表达的影响

目的 评价山莨菪碱对过度训练大鼠肾小管上皮细胞Toll样受体4(TLR4)表达的影响.方法 雄性SD大鼠48只,体重200～220 g,采用随机数字表法,将其随机分为3组:正常对照组(C组,n=8)、力竭运动组(E组,n=24)和山莨菪碱组(A组,n=16).采用大鼠游泳至力竭建立过度训练模型,A组于力竭运动前20 min腹腔注射山莨菪碱10 mg/kg后进行力竭运动.检测肾组织细胞凋亡和肾小管上皮细胞TLR4蛋白、TLR4 mRNA的表达水平.结果 与C组比较,E组和A组细胞凋亡率升高,肾小管上皮细胞TLR4蛋白和TLR4 mRNA表达上调(P＜0.05);与E组比较,A组细胞凋亡率降低,肾小管上皮细胞TLR4蛋白和TLR4 mRNA表达下调(P＜0.05).结论 山莨菪碱可通过下调过度训练大鼠肾小管上皮细胞TLR4表达,抑制肾脏细胞凋亡.     

Neutrophil gelatinase-associated lipocalin protects renal tubular epithelial cell in ischemic/reperfusion injury rats via apoptosis-regulating proteins

We investigated the role of neutrophil gelatinase-associated lipocalin (NGAL) on renal tubular epithelial cell in the renal ischemia/reperfusion injury (IRI) rats. Male Sprague-Dawley rats were randomly assigned to three groups. The control group (n = 5) underwent left nephrectomy. The ischemia/reperfusion (I/R) + normal saline (NS) (n = 5) and I/R + NGAL groups (n = 5) were subjected to 45 min right renal ischemia followed by 48 h of reperfusion after left nephrectomy. The pathological changes of kidney tissues were investigated using hematoxylin-eosin staining; renal tubular epithelial cell apoptosis was detected using terminal dUTP nick-labeling method; expression of apoptosis-regulating protein Fas and Bcl-2 was measured using real-time polymerase chain reaction, Western blot, and immunohistochemical staining. Compared with I/R + NS group, kidney tissues from I/R + NGAL group revealed reduced histological damage and a decreased number of renal tubular epithelial cell apoptosis (9.2 ± 2.53 nuclei or 4.0 ± 0.7 per high-power field vs. 20.3 ± 3.7 nuclei or 8.1 ± 0.3 per high-power field); rats with NGAL showed downregulated fas mRNA (2.34 ± 0.51 vs. 6.84 ± 2.34), fas protein (0.65 ± 0.05 vs. 0.95 ± 0.08), and upregulated bcl-2 protein (0.33 ± 0.05 vs. 0.24 ± 0.03). The results had statistical significance (p < 0.05). We think NGAL could protect against renal IRI and might be related to decreasing tubular epithelial cell apoptosis via adjusting the expression of apoptosis-regulating proteins.     

Sclerosing Encapsulating Peritonitis in an Anti-HCV-Positive Patient on Chronic Ambulatory Peritoneal Dialysis

We investigated the role of neutrophil gelatinase-associated lipocalin (NGAL) on renal tubular epithelial cell in the renal ischemia/reperfusion injury (IRI) rats. Male Sprague–Dawley rats were randomly assigned to three groups. The control group (n = 5) underwent left nephrectomy. The ischemia/reperfusion (I/R) + normal saline (NS) (n = 5) and I/R + NGAL groups (n = 5) were subjected to 45 min right renal ischemia followed by 48 h of reperfusion after left nephrectomy. The pathological changes of kidney tissues were investigated using hematoxylin–eosin staining; renal tubular epithelial cell apoptosis was detected using terminal dUTP nick-labeling method; expression of apoptosis-regulating protein Fas and Bcl-2 was measured using real-time polymerase chain reaction, Western blot, and immunohistochemical staining. Compared with I/R + NS group, kidney tissues from I/R + NGAL group revealed reduced histological damage and a decreased number of renal tubular epithelial cell apoptosis (9.2 ± 2.53 nuclei or 4.0 ± 0.7 per high-power field vs. 20.3 ± 3.7 nuclei or 8.1 ± 0.3 per high-power field); rats with NGAL showed downregulated fas mRNA (2.34 ± 0.51 vs. 6.84 ± 2.34), fas protein (0.65 ± 0.05 vs. 0.95 ± 0.08), and upregulated bcl-2 protein (0.33 ± 0.05 vs. 0.24 ± 0.03). The results had statistical significance (p < 0.05). We think NGAL could protect against renal IRI and might be related to decreasing tubular epithelial cell apoptosis via adjusting the expression of apoptosis-regulating proteins.     

肾上腺髓质素对大鼠肾缺血再灌注损伤中肾小管上皮细胞凋亡的影响及机制研究

目的 观察肾上腺髓质素(adrenomedullin,AM)对大鼠肾缺血再灌注损伤(ischemia reperfusion injury,IRI)中肾小管上皮细胞凋亡的影响,并探讨其机制.方法 Wistar大鼠32只,随机分为4组:假手术组和IRI组各6只,转染空质粒组和转染AM质粒组各10只.大鼠右肾切除后1周,用超声微泡造影剂介导的基因转染方法将大鼠AM真核表达质粒转染大鼠肾脏,1周后采用免疫组织化学方法检测转染效率.转染成功后夹闭左肾动脉45 min制作肾IRI模型,于再灌注24 h后留取肾组织标本.TUNEL染色检测肾组织细胞凋亡,RT-PCR检测肾组织Bcl-2、Bax和Fas的mRNA表达,蛋白质印迹法检测caspase-3、caspase-8和caspase-9蛋白质表达.结果 转染AM质粒组的AM表达显著高于转染空质粒组(0.51±0.09和0.23±0.05,P＜0.05).与假手术组相比,IRI组肾组织细胞凋亡率明显增加[(38.79±7.52)%和(2.89±0.52)%,P＜0.05];肾组织Bax、Bcl-2、Fas、caspase-3、caspase-8和caspase-9表达上调,分别为0.72±0.18和0.23±0.04、0.80±0.12和0.38±0.06、1.24±0.25和0.39±0.09、0.76±0.13和0.38±0.08、0.92±0.14和0.32±0.06、0.89±0.12和0.42±0.09(P＜0.05),Bax/Bcl-2升高(0.91±0.18和0.61±0.08,P＜0.05).转染AM质粒组肾组织凋亡细胞数、Bax、Fas、caspase-3、caspase-8和caspase-9表达下调,分别为(19.36±6.78)%、0.48±0.11、0.62±0.07、0.53±0.08、0.46±0.08、0.51±0.12,与IRI组比较差异均有统计学意义(P＜0.05);Bcl-2表达进一步上调为1.23±0.25,Bax/Bcl-2降低为0.44±0.12,与IRI组比较差异均有统计学意义(P＜0.05).转染空质粒组和IRI组比较,上述各指标差异均无统计学意义(P＞0.05).结论 AM能减轻肾IRI引起的肾小管上皮细胞凋亡,其部分机制可能是通过抑制caspase依赖的内、外源性凋亡途径实现的.

Abstract：

Objective To investigate the effect and mechanism of adrenomedullin (AM) on apoptosis of renal tubular epithelial cell in rats induced by renal ischemia reperfusion injury. Methods Thirty-two Wistar rats were randomly divided into 4 groups: control group, IRI group, empty plasmid group and AM group. One week after removing the right kidney, eukaryotic expression vector encoding rat AM gene was transfected into the left kidney using an ultrasound-microbubble mediated system. After 1 week the transfer efficiency was detected by immunohistochemical method . Renal IRI model induced by clamping left renal arteries for 45 min followed by reperfusion for 24 h. Tubular cell apoptosis was detected by TUNEL assay. Bcl-2, Bax and Fas expressions were examined by RT-PCR. The expressions of caspase-3, caspase-8 and caspase-9 were determined by Western bolt analysis. Results The expression of AM in the AM group was significantly higher than the empty plasmid group (0.51±0.09 vs 0.23±0.05; P<0.05). Compared with the control group, the apoptosis rate of renal tubular cell in the IRI group was significantly higher [(38.79±7.52)% vs (2.89±0.52)%; P<0.05]. The expressions of Bax, Bcl-2, Fas, caspase-3, caspase-8 and caspase-9 were also significantly increased (0.72±0.18 vs 0.23±0.04, 0.80±0.12 vs 0.38±0.06, 1.24±0.25 vs 0.39±0.09, 0.76±0.13 vs 0.38±0.08, 0.92±0.14 vs 0.32±0.06, 0.89±0.12 vs 0.42±0.09; P<0.05). Bax/Bcl-2 was also significantly increased (0.91±0.18 vs 0.61±0.08; P<0.05). Compared with the IRI group, AM pretreatment significantly decreased the apoptosis rate of renal tubular cells [(19.36±6.78)% vs (38.79±7.52)%; P<0.05]. AM inhibited the up-regulation of Bax, Fas, caspase-3, caspase-8 and caspase-9, while promoting the up-regulation of Bcl-2 (0.48±0.11 vs 0.72±0.18, 0.62±0.07 vs 1.24±0.25, 0.53±0.08 vs 0.76±0.13, 0.46±0.08 vs 0.92±0.14, 0.51±0.12 vs 0.89±0.12, 1.23±0.25 vs 0.80±0.12; P<0.05). Bax/Bcl-2 significantly decreased (0.44±0.12 vs 0.91±0.18; P<0.05). The above parameters had no significant diffe-rence between the empty plasmid group and the IRI group (P>0.05). Conclusion AM can reduce apoptosis of renal tubular epithelial cell induced by renal IRI, the mechanism of which might be achieved by inhibiting caspase-dependent intrinsic and extrinsic pathways.     

内质网应激PERK/eIF2α通路在草酸钙诱导肾小管上皮细胞损伤中的作用

目的 探讨内质网应激蛋白激酶R样内质网激酶（PERK）/真核翻译起始因子2α（eIF2α）通路在草酸钙诱导的肾小管上皮细胞损伤中的作用机制。〖HT5”H〗方法〓〖HT5”SS〗将人肾小管上皮细胞（HK-2）分为对照组、草酸钙组和草酸钙+4 苯基丁酸组。草酸钙组和草酸钙+4-苯基丁酸组在培养基中加入终浓度为5 mmol/L的草酸钙诱导细胞损伤模型,草酸钙+4-苯基丁酸组在培养基中另加入终浓度为2 mmol/L的4-苯基丁酸。通过CCK-8法、流式细胞术和DCFH DA荧光探针检测细胞活力、凋亡和细胞内活性氧（ROS）水平,并分析细胞内PERK/eIF2α通路中蛋白以及Caspase12和Caspase3表达水平。结果 草酸钙组的OD值（0.42±0.05）低于对照组（0.71±0.08）,草酸钙+4-苯基丁酸组的OD值（0.65±0.07）高于草酸钙组（均P<0.05）。草酸钙组的细胞凋亡率、ROS水平、PERK和eIF2α蛋白水平、Caspase12、Caspase3 mRNA和蛋白水平高于对照组,差异均有统计学意义（均P<0.05）。草酸钙+4-苯基丁酸组的细胞凋亡率、ROS水平、PERK和eIF2α蛋白水平、Caspase12、Caspase3的mRNA和蛋白水平低于草酸钙组,差异均有统计学意义（P<0.05）。结论 在草酸钙诱导的肾小管上皮细胞损伤中使用4-苯基丁酸抑制内质网应激可抑制PERK/eIF2α通路并缓解细胞凋亡。     

bcl-2高表达提高肾小管上皮细胞抗凋亡能力的研究

目的 观察凋亡相关基因bcl-2高表达抑制过氧化氢诱导肾小管上皮细胞凋亡的作用.方法 构建含有人bcl-2 cDNA的逆转录病毒真核表达载体PLXSN,脂质体法将重组质粒转染PA317细胞,G418筛选阳性克隆,鉴定后浓缩收集病毒上清,浓缩病毒液,感染人肾小管上皮细胞株HK-2,Western blot检测bcl-2 mRNA表达.5 mmol/L过氧化氢(HO2)诱导细胞凋亡后,流式细胞仪检测细胞凋亡发生变化.结果 流式细胞仪分析显示5 mmol/L H2O2:成功诱导肾小管上皮细胞凋亡,bel-2逆转录病毒感染肾小管上皮细胞后,bcl-2蛋白水平呈高表达,HK bcl-2组细胞凋亡数量(12.41±3.46)较HK-2组(19.62±4.20)显著减少(P<0.05).而转染空载体的对照组无明显变化(19.62±4.20,P<0.05).结论 bel-2蛋白高表达显著抑制氧化剂诱导的肾小管上皮细胞凋亡.     

intermedin对大鼠肾脏缺血再灌注损伤的保护作用及其机制

目的 观察intermedin（IMD）对大鼠肾脏缺血再灌注损伤（IRI）的保护作用并探讨其机制。 方法 健康雄性Wistar大鼠24只随机分为对照组、IRI组、转空质粒组、转IMD质粒组。动物右肾切除后,用超声微泡技术将质粒转染入肾脏,1周后制作肾脏IRI模型。PAS染色观察肾脏病理损伤,比色法检测肾组织超氧化物岐化酶（SOD）、髓过氧化物酶（MPO）和天冬氨酸半胱氨酸蛋白酶3（caspase-3）,以及脂质过氧化物丙二醛（MDA）含量。免疫组织化学方法检测细胞间黏附分子1（ICAM-1）、P选择素及内皮素1（ET-1）表达。TUNEL染色检测肾组织细胞凋亡。 结果 PAS染色结果显示,IRI组肾小管及间质病理损伤显著重于对照组（P < 0.01）;转IMD组肾组织病理损伤则显著轻于IRI组（P < 0.01）。IRI组肾组织SOD活性显著低于对照组（P < 0.05）,MPO活性、活性caspase-3、MDA含量及ICAM-1、P选择素和 ET-1表达均显著高于对照组（均P < 0.01）;转IMD组SOD活性显著高于IRI组（P < 0.05）,MPO活性、活性caspase-3、MDA含量及ICAM-1、P选择素和ET-1表达均显著低于IRI组（均P < 0.01）。TUNEL染色显示,IRI组肾组织凋亡细胞数显著高于对照组（34.83%±8.75%比3.33%±0.47%,P < 0.01）;转IMD组肾组织凋亡细胞数（20.67%±7.71%）则较IRI组显著减轻（P < 0.01）。转空质粒组和IRI组以上指标差异均无统计学意义。 结论 IMD能减轻肾脏IRI,其机制至少部分与抑制氧自由基生成、炎细胞浸润及炎性因子ICAM-1、P选择素生成、ET-1生成、细胞凋亡有关,从而减轻肾组织局部氧化应激反应产生的活性氧。     

外源性硫化氢抑制TLR2和TLR4表达并减轻大鼠肾脏缺血再灌注损伤

目的观察外源性硫化氢(H₂S)供体硫氢化钠(NaHS)能否抑制Toll样受体2(TLR2)和Toll样受体4(TLR4)表达、减轻大鼠肾脏缺血再灌注损伤(IRI)。 方法24只6~8周龄雄性SD大鼠随机分为3组：假手术(Sham)组、肾脏缺血再灌注(I/R)组、NaHS+I/R组。采用右肾切除联合左肾动脉夹闭45 min后再灌注24 h的方法诱导肾IRI。夹闭左肾动脉前，NaHS+I/R组给予NaHS(300 nmol/min)连续输注10 min，Sham组和I/R组则给予等体积生理盐水。分别留取各组腹主动脉血及肾组织标本。Western印迹法检测肾组织TLR2、TLR4蛋白的表达；免疫组织化学法检测肾组织白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)的表达；比色法检测血尿素氮(BUN)、血肌酐(Scr)。HE染色观察肾脏组织学改变；TUNEL法检测肾组织细胞凋亡。 结果与Sham组比较，I/R组的TLR2、TLR4、IL-6、TNF-α表达均增加(P<0.05)，BUN、Scr亦明显升高(P<0.05)，肾小管上皮损伤评分较高(P<0.05)，肾组织凋亡细胞增加(P<0.05)。与I/R组比较，NaHS+I/R组的TLR2、TLR4、IL-6、TNF-α表达均减少(P<0.05)，BUN、Scr亦明显下降(P<0.05)，肾小管上皮损伤评分较低(P<0.05)，肾组织凋亡细胞减少(P<0.05)。 结论外源性H₂S可以抑制TLR2、TLR4途径，减少炎症因子释放及细胞凋亡，减轻大鼠肾脏IRI。     

Expression and function of Erbin protein in renal ischemia-reperfusion injury

Objective To investigate the expression of ErbB2 interacting protein (Erbin) in renal ischemia-reperfusion injury (IRI) in vivo and in vivo, and the effect of Erbin over-expression on IRI. Methods (1) In vivo, the model of renal IRI was constructed in mice, and set up sham group and reperfusion 3, 6, 12, 24 and 48 h IRI group. BUN and Scr were detected and PAS staining was used to observe the pathology change of renal tissues. Cell apoptosis was detected by TUNEL staining. Erbin and NF-κB expression in renal tissue was detected by Western blotting, and immunohistochemistry was used to detect the distribution of Erbin. (2) In vivo, IRI model in HK2 cells was constructed and cells were harvested after culturing in normal medium for 3, 6, 12 and 24 h. Erbin expression was detected by Western blotting. Flow cytometry and ELISA were used to evaluate the level of cell apoptosis and inflammatory cytokine secretion respectively. HK2 cells were transiently transfected with Prk5-myc-Erbin plasmid via lipofectamine 2000, and were divided into control group, IRI group, Erbin group and Erbin+IRI group. The protein expression of Erbin and NF-κB, cell apoptosis and inflammatory cytokine secretion was detected. Results (1) Compared with sham group, serum BUN and Scr were dramatically increased in IRI model, especially in 24 h after reperfusion (P＜0.05). Moreover, PAS staining showed that a lot of renal tubular epithelial cells were necrosis and fell off, and many protein cast were formed, renal injury score and apoptotic index were higher in 6 h, 12 h, 24 h, 48 h IRI model than those in sham group (all P＜0.05). The expression of Erbin, which was expressed in renal tubules, and nuclear NF-κB in 24 h IRI model were significantly increased, as compared with sham group (all P＜0.05). (2) Compared to those in control group, nuclear NF-κB expression, apoptosis and inflammatory cytokine secretion were significantly increased in IRI group. Meanwhile, Erbin expression was also induced and peaked at 24 h (P＜0.05). Compared to those in IRI group, cell apoptosis, the expression of nuclear NF-κB, inflammatory cytokine IL-6 and TNF-α were decreased in Erbin+IRI group (all P＜0.05). Conclusions Erbin expression is up-regulated in renal IRI, and over-expression of Erbin can partly inhibit NF-κB activation, cell apoptosis and inflammatory cytokine secretion in IRI group, which indicates Erbin may playing a protective role in renal IRI.     

Delayed administration of darbepoetin or erythropoietin protects against ischemic acute renal injury and failure

Administration of human recombinant erythropoietin (EPO) at time of acute ischemic renal injury (IRI) inhibits apoptosis, enhances tubular epithelial regeneration, and promotes renal functional recovery. The present study aimed to determine whether darbepoetin-alfa (DPO) exhibits comparable renoprotection to that afforded by EPO, whether pro or antiapoptotic Bcl-2 proteins are involved, and whether delayed administration of EPO or DPO 6 h following IRI ameliorates renal dysfunction. The model of IRI involved bilateral renal artery occlusion for 45 min in rats (N = 4 per group), followed by reperfusion for 1-7 days. Controls were sham-operated. Rats were treated at time of ischemia or sham operation (T0), or post-treated (6 h after the onset of reperfusion, T6) with EPO (5000 IU/kg), DPO (25 mug/kg), or appropriate vehicle by intraperitoneal injection. Renal function, structure, and immunohistochemistry for Bcl-2, Bcl-XL, and Bax were analyzed. DPO or EPO at T0 significantly abrogated renal dysfunction in IRI animals (serum creatinine for IRI 0.17 +/- 0.05 mmol/l vs DPO-IRI 0.08 +/- 0.03 mmol/l vs EPO-IRI 0.04 +/- 0.01 mmol/l, P = 0.01). Delayed administration of DPO or EPO (T6) also significantly abrogated subsequent renal dysfunction (serum creatinine for IRI 0.17 +/- 0.05 mmol/l vs DPO-IRI 0.06 +/- 0.01 mmol/l vs EPO-IRI 0.03 +/- 0.03 mmol/l, P = 0.01). There was also significantly decreased tissue injury (apoptosis, P < 0.05), decreased proapoptotic Bax, and increased regenerative capacity, especially in the outer stripe of the outer medulla, with DPO or EPO at T0 or T6. These results reaffirm the potential clinical application of DPO and EPO as novel renoprotective agents for patients at risk of ischemic acute renal failure or after having sustained an ischemic renal insult.