雷公藤甲素对高糖刺激足细胞synaptopodin和desmin表达影响

EFFECTS OF TRIPTOLIDE ON PODOCYTE SYNAPTOPODIN AND DESMIN EXPRESSIONS IN HIGH GLUCOSE ENVIRONMENT

目的通过观察高糖刺激对小鼠足细胞synaptopodin和desmin表达影响及雷公藤甲素（TP）对其干预作用,探讨TP减少糖尿病肾病尿蛋白的分子机制。方法以体外培养小鼠永生化足细胞为研究对象,将其分为正常糖组、高糖刺激组、甘露醇对照组、低剂量TP干预组和高剂量TP干预组5组,分别加含有5.5mmol/L的D-葡萄糖、含有30.0mmol/L的D-葡萄糖、含有5.5mmol/L的D-葡萄糖＋24.5mmol/L甘露醇、含有30.0mmol/L的D-葡萄糖＋3μg/L的TP、含有30.0 mmol/L的D-葡萄糖＋10μg/L的TP培养液培养48h。应用荧光定量PCR法和Western Blot方法检测各组足细胞synaptopodin、desmin mRNA和蛋白的表达。结果与正常糖组相比,高糖刺激组足细胞synaptopodin mRNA和蛋白的表达增加,desmin mRNA和蛋白的表达减少;低剂量TP干预和高剂量TP干预组synaptopodin mRNA和蛋白表达水平均较高糖刺激组升高,而desmin mRNA和蛋白表达水平较高糖刺激组降低,且呈一定的剂量-效应关系,差异有显著性（F=25.919~551.012,P〈0.05）。结论 TP可以改善高糖诱导的足细胞synaptopodin和desmin表达异常,这可能是TP减少糖尿病肾病尿蛋白的机制之一。

Objective To investigate the molecular mechanism of triptolide （TP） that reduces urine protein in diabetic nephropathy through investigating the effects of high glucose activation on expressions of synaptopodin and desmin in mouse podo cytes and the intervention of TP on it. Methods Immortalized mouse podocyte cells cultured in vitro were the object of this stu- dy, which were divided into five groups as normal glucose group, high-glucose-stimulus group, mannitol group, low-dose TP-inter- vention group and high-dose TP-intervention group. Culture solutions that contain 5.5 mmol/L D-glucose, 30.0 mmol/L D-glucose, 5.5 mml/L D-glucose＋3μg/L of TP and 30.0 mmol/LD-glucose＋10 μg/L of TP were respectively added in each group and incu- bated for 48 h. The expressions of synaptopodin and desmin mRNA and protein in podocyte cells were detected by fluorescent quan- titation PCR and Western blot. Results Compared with normal glucose group, the expressions of synaptopodin mRNA and pro- tein in the high-glucose stimulus group increased, and that of desmin mRNA and protein decreased; In the low-and high TP-con- centration groups, the expressions of synaptopodin mRNA and protein were higher than that in the high-glucose stimulus group, and that of desmin mRNA and protein were lower, with dose-effect relationship, the difference being significant （F = 25. 919- 551.012,P〈0.05）. Conclusion Triptolide can improve high-glucose-induced abnormal expressions of synaptopodin and desmin in podocyte cells, which is likely to be one of the mechanisms of triptolide in reducing proteinuria in diabetic nephropathy.