雷公藤内酯醇对小鼠肾小球足细胞裂孔隔膜核心蛋白表达干预作用的研究

摘要

目的观察雷公藤内酯醇（TP）干预高糖环境培养的小鼠肾小球足细胞裂孔隔膜nephrin、podocin和CD2AP的表达，探讨雷公藤治疗糖尿病肾病（DN）蛋白尿的分子生物学机制。方法培养成熟的小鼠足细胞随机分为对照组1、对照组2、高糖组和TP干预组，TP干预组进一步分为低剂量、中剂量和高剂量组。用不同浓度的TP（8、16和32ng/ml）干预高糖（25mmol/L的Glu）培养24h后的小鼠足细胞，用 RT- PCR法检测干预前后nephrin、podocin和CD2AP mRNA的表达；用间接免疫荧光法检测16ng/ml TP干预后nephrin和podocin蛋白的表达。结果（1）与对照组相比，高糖诱导的足细胞nephrin、podocin和CD2AP mRNA表达均明显减弱（均P＜0.01）。（2）TP显著上调高糖诱导的足细胞nephrin、podocin和CD2AP mRNA的表达（均P＜0.05）。（3）16ng/ml TP能明显上调高糖对足细胞nephrin和podocin（均P＜0.05）蛋白表达的抑制。结论 TP显著上调高糖诱导的足细胞nephrin、podocin和CD2AP的表达，可能是其降低DN蛋白尿的机制之一。%Objective To investigate the effect of triptolide (TP) on the expression of GPSD core proteins in mouse podocytes induced by high glucose. Methods The cultured mouse podocyte were randomly divided into control group1, control group2, high glucose group and TP treatment groups, which were further divided into low, middle and high dose subgroups. Podocyte exposed to 25 mmol/L glucose were treated with different doses of triptolide (8,16 and 32ng/ml). The expressions of nephrin, podocin and CD2AP mRNA were examined by RT- PCR. The expressions of nephrin and podocin protein were detected by indirect immunoflorescence technique (IIFT). Results Compared to control group, the expression of nephrin, podocin and CD2AP mRNA in high glucose group were significantly decreased (P<0.05 or P<0.01). Compared to high glucose group, the expression of nephrin, podocin and CD2AP mRNA were significantly up- regulated (P<0.05) in 3 TP- treatment groups, and the expression was highest in middle dose group (P<0.05). IIFT demonstrated that the inhibited expression of nephrin and podocin by high- glucose was significantly up- regulated in the middle dose group. Conclusion The expressions of nephrin, podocin and CD2AP in the mouse podocyte are inhibited in high glucose condition. These core proteins inhibited in high glucose can be sig-nificantly up- regulated by triptolide, indicating that it may attenuate the proteinuria in diabetic hephropathy.