阿奇霉素对大鼠阿霉素肾病的干预作用

目的 通过观察阿奇霉素对阿霉素肾病大鼠血、尿生化指标、肾脏组织病理以及细胞间黏附因子1（ICAM-1）、nephrin与podocalyxin在肾组织表达的影响,探讨其在大鼠阿霉素肾病中的干预作用。 方法 建立大鼠阿霉素肾病模型,分为阿奇霉素治疗组、泼尼松治疗组、联合治疗组、模型组及正常对照组。监测实验0、4、8周24 h尿蛋白量（24 h-up）及血生化指标动态变化,计算内生肌酐清除率（Ccr）。观察肾组织病理形态学改变。免疫组化SP法观察肾组织中ICAM-1、nephrin、podocalyxin的表达。 结果 实验4周时尿蛋白及白蛋白指标均达到肾病模型要求,提示模型制作成功。实验8周,与模型组相比,各治疗组大鼠的各项观察指标均有不同程度改善,24 h-up、胆固醇、Scr显著降低（P < 0.05）,总蛋白、Alb及Ccr（除外C组）有所增加（P < 0.05）,肾组织病理改变减轻,肾脏病理积分及细胞外基质/肾小球面积比值降低（P < 0.01）,肾小球及肾小管ICAM-1表达减少（P < 0.01）,nephrin、podocalyxin表达增高。综合比较,其中联合治疗组疗效最好。 结论 阿奇霉素对阿霉素肾病大鼠的干预有类似于泼尼松样的治疗作用,但其对早期肾功能的保护作用逊于泼尼松,而二者联合应用可起到协同治疗的作用,其药效明显优于两药的单独应用。     

Rosiglitazone enhances glucose uptake in glomerular podocytes using the glucose transporter GLUT1

Aims/hypothesis  Peroxisome proliferator-activated receptor (PPAR) γ agonists are used increasingly in the treatment of type 2 diabetes. In the context of renal disease, PPARγ agonists reduce microalbuminuria in diabetic nephropathy; however, the mechanisms underlying this effect are unknown. Glomerular podocytes are newly characterised insulin-sensitive cells and there is good evidence that they are targeted in diabetic nephropathy. In this study we investigated the functional and molecular effects of the PPARγ agonist rosiglitazone on human podocytes. Methods  Conditionally immortalised human podocytes were cultured with rosiglitazone and functional effects were measured with glucose-uptake assays. The effect of rosiglitazone on glucose uptake was also measured in 3T3-L1 adipocytes, nephrin-deficient podocytes, human glomerular endothelial cells, proximal tubular cells and podocytes treated with the NEFA palmitate. The role of the glucose transporter GLUT1 was investigated with immunofluorescence and small interfering RNA knockdown and the plasma membrane expression of GLUT1 was determined with bis-mannose photolabelling. Results  Rosiglitazone significantly increased glucose uptake in wild-type podocytes and this was associated with translocation of GLUT1 to the plasma membrane. This effect was blocked with GLUT1 small interfering RNA. Nephrin-deficient podocytes, glomerular endothelial cells and proximal tubular cells did not increase glucose uptake in response to either insulin or rosiglitazone. Furthermore, rosiglitazone significantly increased basal and insulin-stimulated glucose uptake when podocytes were treated with the NEFA palmitate. Conclusions/interpretation  In conclusion, rosiglitazone has a direct and protective effect on glucose uptake in wild-type human podocytes. This represents a novel mechanism by which PPARγ agonists may improve podocyte function in diabetic nephropathy.     

Urinary podocyte-associated mRNA profile in Egyptian patients with diabetic nephropathy

IntroductionPodocyte injury and subsequent excretion in urine play a crucial role in the pathogenesis and progression of diabetic nephropathy (DN). Quantification of messenger RNA expression in urinary sediment by real-time PCR is emerging as a noninvasive method of screening DN-associated biomarkers. We aimed to study the expression of podocyte-associated genes in urinary sediment and their relation to disease severity in type 2 diabetic Egyptian patients with diabetic nephropathy.Methodology: Sixty patients with type 2 diabetes mellitus were recruited in addition to twenty non diabetic healthy volunteers. Relative mRNA abundance of nephrin, podocalyxin, and podocin were quantified, and correlations between target mRNAs and clinical parameters were examined.ResultsThe urinary mRNA levels of all genes studied were significantly higher in diabetics compared with controls (p < 0.001), and mRNA levels increased with DN progression. Urinary mRNA levels of all target genes positively correlated with both UAE and HbA_1c. The expression of nephrin, podocalyxin, and podocin mRNA correlated with serum creatinine {(r = 0.397, p value = 0.002), (r = 0.431, p value = 0.001), (r = 0.433, p value = 0.001) respectively}.ConclusionThe urinary mRNA profiles of nephrin, podocalyxin, and podocin were found to increase with the progression of DN, which suggested that quantification of podocyte-associated molecules will be useful biomarkers of DN.     

绞股蓝总皂苷对糖尿病肾病大鼠足细胞损伤的影响及机制

目的:研究绞股蓝总皂苷对糖尿病肾病(DN)大鼠肾脏足细胞相关分子(nephrin)、血管通透因子(VEGF)mRNA表达的影响,探讨其降低尿蛋白、保护肾脏的机制。方法:采用单侧肾切除加链脲佐菌素(STZ)注射法改良复制DN模型,实验分为正常组、模型组、治疗组(绞股蓝总皂苷高、中、低剂量组)和缬沙坦组。干预4周后电镜观察肾小球超微结构改变,RT-PCR检测nephrin、VEGF mRNA表达。结果:各治疗组病理变化较模型组均有不同程度改善:足突增宽或部分融合,基底膜增厚减轻,同时nephrin mRNA表达水平较模型组明显上调(P0.01),VEGF表达明显抑制(P0.01),其中高剂量组和缬沙坦组效果类似,明显优于低剂量组(P0.01)。结论:绞股蓝总皂苷可能通过上调足细胞相关分子nephrin表达,抑制分泌VEGF过表达,减轻足细胞超微结构改变,从而保护足细胞,降低尿蛋白,延缓肾小球硬化。     

复肾功方对慢性肾功能衰竭大鼠肾脏nephrin mRNA表达的影响

目的 研究复肾功方对慢性肾功能衰竭（chronic renal failure,CRF）大鼠肾组织足细胞裂孔隔膜蛋白（nephrin） mRNA表达的影响,探讨其降低尿蛋白、减轻肾损害的作用机制。方法 将55只雄性SD大鼠随机分为正常组,模型组,复肾功方低、中、高剂量组,每组11只。正常组常规饲养,其余4组大鼠食用含腺嘌呤饲料建立慢性肾功能衰竭模型,连续喂养21 d。造模成功后,所有大鼠改用常规饲料。正常组和模型组按20 mL/(kg·d)灌胃给予生理盐水;复肾功方低、中、高剂量组按大鼠体质量分别以生药4、8、16 g/kg灌胃复肾功方,1次/d,连续灌胃30 d。实验结束后,收集大鼠尿液测定24 h尿蛋白定量,检测各组大鼠血清血肌酐(SCr)和尿素氮（BUN）水平,HE染色检测肾小球组织形态学改变,免疫荧光检测nephrin蛋白表达,Real-Time PCR法观察肾脏nephrin mRNA表达情况。结果 与正常组比较,模型组24 h尿蛋白定量、SCr和BUN水平升高(P<0.05),nephrin蛋白及mRNA表达下降（P<0.05);与模型组比较,经复肾功方治疗后,24 h尿蛋白定量、SCr和BUN水平降低（P<0.05）,肾组织nephrin蛋白及mRNA的表达升高（P<0.05）。结论 复肾功方降低CRF大鼠尿蛋白,减轻肾损害程度,其机制可能与升高肾组织nephrin蛋白及mRNA的表达、减轻足细胞损伤有关。     

阿霉素肾病大鼠中肾小球nephrin表达与氧化应激反应的关系

目的：氧化和抗氧化失衡可能是肾病综合征产生大量蛋白尿的原因之一,而肾小球裂隙膜分子nephrin在维持肾小球滤过屏障功能中起着重要作用。因此该实验初步探讨阿霉素肾病大鼠肾小球裂隙膜分子nephrin表达与氧化应激反应的关系,以及泼尼松和维生素E对阿霉素大鼠肾损伤保护作用的机制。方法：尾静脉单次注射阿霉素5 mg/kg建立肾病发病过程中的氧化应激模型,并增加泼尼松和维生素E干预。应用化学比色法检测肾皮质氧化应激指标变化,应用免疫组织化学技术观察肾小球裂隙膜分子nephrin表达变化,并对两者进行相关性分析。结果：①肾病组大鼠肾皮质丙二醛（MDA）含量及24 h尿蛋白排泄量高于正常对照组,超氧化物歧化酶（SOD）和总抗氧化能力（T-AOC）活性低于正常对照组。与肾病组相比,泼尼松和维生素E干预组从14 d开始尿蛋白排泄量明显减少,直到28 d（P<0.05）。维生素E干预组肾皮质MDA含量较肾病28 d组下降,SOD、T-AOC活性较肾病28 d组升高。②正常对照组大鼠nephrin沿肾小球基底膜呈深褐色连续线性分布;肾病组随时间的延长深褐色连续线性分布向浅褐色短线条状或点状分布转化;泼尼松和维生素E干预组减轻了nephrin分子的异常改变;量化分析显示,肾病组肾小球nephrin阳性表达含量明显低于正常对照组,泼尼松及维生素E干预组肾小球nephrin阳性表达含量较肾病组增加。③肾小球nephrin蛋白阳性表达含量与肾皮质MDA含量呈负相关,与肾皮质SOD和T-AOC活性呈正相关。结论：肾小球裂隙膜分子nephrin表达减少与氧化应激反应密切相关;泼尼松和维生素E对阿霉素肾病大鼠肾损伤有保护作用。［中国当代儿科杂志,2009,11（1）：56-60］     

骨髓间充质干细胞移植对嘌呤霉素氨基核苷肾病大鼠足细胞修复作用的研究

目的：探讨骨髓间充质干细胞(bone mesenchymal stem cells,BMSCs)移植对嘌呤霉素氨基核苷(puromycin aminonucleoside,PAN)肾病大鼠足细胞修复作用及其对裂孔隔膜分子Nephrin表达的影响,为BMSCs移植治疗肾病综合征提供实验依据。方法：45只雄性Sprague-Dawley大鼠随机分为 3组,每组15只。模型组：一次性腹腔注射PAN（0.15 mg/g）造模;BMSCs组：PAN造模+BMSCs移植（细胞移植前经Brdu标记示踪）;对照组：不予以造模。实验第10天杀鼠,留取标本行血、尿、肾组织超微结构检测,免疫组化检测肾脏Brdu标记阳性细胞的表达,半定量RT-PCR及Western blot方法检测Nephrin 表达变化。结果：模型组大鼠出现大量蛋白尿、血白蛋白降低、胆固醇升高,伴有广泛足突的融合。与模型组比较,BMSCs组尿蛋白、血胆固醇降低,血白蛋白回升及足突融合现象改善,差异有统计学意义（P＜0.05）;免疫组化显示,BMSCs组肾组织中可见阳性细胞,模型组及对照组未见阳性细胞;半定量RT-PCR及Western blot显示,模型组Nephrin相对表达量较对照组明显下降,BMSCS组与模型组比较有所增加,差异有统计学意义（P＜0.05)。结论：BMSCs移植对PAN肾病大鼠足突融合有一定的改善,Nephrin表达的变化可能在其中发挥了作用。［中国当代儿科杂志,2010,12（6）：483-487］     

坎地沙坦对糖尿病肾病大鼠足细胞Nephrin、Podocin和CD2AP表达的影响

目的探讨糖尿病肾病(DN)大鼠足细胞相关分子Nephrin、Podocin及CD2AP表达的变化,以及坎地沙坦对其的干预作用,为DN的防治提供理论依据。方法健康雄性SD大鼠36只,随机分为3组:A组为正常对照组,B组为DN组,C组为DN+坎地沙坦组。用药后第4周和第7周检测各组大鼠的血糖(GLU)、体重、24h尿蛋白(proteinuria)和内生肌酐清除率(Ccr),于第7周予RT-PCR法检测大鼠肾组织Nephrin、Podocin及CD2AP mRNA表达。结果 7周后,与A组比较,B组出现尿蛋白排泄增多,Ccr下降(P<0.05),肾组织Nephrin、Podocin及CD2AP mRNA水平均下调(均P<0.05);与B组比较,C组尿蛋白排泄量降低(P<0.05),Ccr升高(P<0.05),Nephrin、Podocin及CD2AP mR-NA水平均增加(均P<0.05)。采用直线相关分析后发现,尿蛋白与肾组织Nephrin、Podocin和CD2AP mRNA水平呈负相关;Ccr与肾组织Nephrin、Podocin和CD2AP mRNA水平呈正相关。结论 DN时存在足细胞分子Nephrin、Podo-cin及CD2AP表达异常,坎地沙坦对肾脏的保护作用机制可能是通过增加Nephrin、Podocin及CD2AP表达而实现。