雷公藤多苷对2型糖尿病肾脏疾病大鼠肾脏保护作用的研究

Study on protective effect of tripterygium wilfordii polyglucosides inrats with type 2 diabetic kidney disease

目的观察雷公藤多苷对STZ诱导的糖尿病肾脏疾病(DKD)大鼠肾脏中细胞核因子κB受体活化因子/核因子κB受体活化因子配体(RANK/RANKL)的表达变化,探讨其保护肾脏的机制。方法采用高糖高脂喂养加STZ腹腔注射法建立T2DM动物模型,造模成功后随机分为DKD模型组(DKD,n=8)和雷公藤多苷组(DT,n=8),另选健康大鼠作为正常对照组(NC,n=8)。DT组予雷公藤多苷50mg/(kg·d)剂量灌胃,NC组和DN组每日予等量生理盐水灌胃。12周后处死大鼠,检测FPG、FIns、UAlb、BUN、Scr、Ucr,计算Ccr。PAS染色观察肾脏病理改变,免疫组织化学法检测肾脏中RANK、RANKL的表达分布,Western blot检测RANK、RANKL、Nephrin的蛋白表达。结果与NC组比较,DKD组FPG、FIns、UAlb、Ccr、BUN在给药12周末表达均升高,肾脏中RANK[(0.27±0.05)vs(0.68±0.11)]、RANKL[(0.23±0.07)vs(0.62±0.08)]蛋白表达增加,而Nephrin表达水平下降(P<0.01);与DN组比较,DT组上述生化指标均改善,肾脏病理改变减轻;RANK[(0.45±0.09)vs(0.68±0.11)]、RANKL[(0.39±0.06)vs(0.62±0.08)],而Nephrin蛋白表达增多(P<0.01)。结论雷公藤多苷可以抑制RANK/RANKL的表达,减轻T2DM大鼠肾脏病理改变,减少蛋白尿,起到肾脏保护作用。

Objective To observe the changes in the expression of RANK/RANKL in rat kidney treated by tripterygium wilfordii polyglucosides （TWP） in STZ induced type 2 diabetic kidney disease （DKD） and to explore its possible renoprotective mechanism. Methods T2DM animal model was established by high glucose and high fat diet plus intraperitoneal injection of STZ. The modeled rats were randomly divided into DKD group（DKD,n=8） and TWP treatment group（DT, n=8）. Normal rats were taken as control group（NC,n=8）. DT rats were lavaged with TWP in a dose of 50 mg/kg·d, while the NC group and DKD group were lavaged with equal volume of normal saline every day. The indicators of FPG, Fins, UA1b, BUN, Scr, and Ucr were measured before and after 12-week intervention. PAS staining was used to evaluate the pathological change of the kidney. Immunohistochemistry and Western-blot were used to observe the protein expressions of RANK, RANKL, and nephrin. Results Compared with NC group, kidney pathological changes of DN group were aggravated with higher levels of FPG, UAlb, Ccr and BUN at 12th week. The expressions of RANK[-（0.27±0.05） vs （0.68±0.11）] and RANKL[（0.23± 0.07） vs （0. 62±0.08）] were prominently increased in kidney in DN group than those in NC group,while the expressions of nephrin were decreased（P〈0.01）. Compared with DKD group, the above indexes and renal pathological changes were improved in DT group. The expressions of RANK[（0.45±0.09） vs （0.68±0.11）],and RANKLE（0.39 ± 0.06） vs （0.62 ±0.08）], were markedly inhibited in DT group, while nephrin expressions were increased（P〈0.01）. Conclusion TWP can protect the kidney in rats with DKD by inhibiting the expression of RANK/RANKL.