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.

Effects of Dangshen extract saponin on apoptosis and the mechanism in ischemia-reperfusion injury of renal grafts

Objective To investigate the effects of Dangshen (DS) extract saponins alleviating apoptosis in ischemia-reperfusion injury (I/R) of renal grafts and the mechanism. Methods The I/R injury model in SD rats was established after kidney transplantation. The SD rats were randomly divided into the following 3 groups (n = 20): sham operation group, I/R model group, DS saponin intervention group. Blood urea nitrogen (Bun) and creatinine (Scr) levels were determined at the 24th h after operation; apoptosis index (AI) was detected by using TUNEL method; the expression of Bcl2 and bax mRNA was detected by RT-PCR. Results As compared with the sham operation group,the blood Bun and Scr levels were significantly increased in the I/R model and DS saponin intervention groups (P＜0. 05). As compared with the DS saponin intervention group, the blood Bun and Scr levels were significantly increased in the I/R group (P＜0.05). The AI was significantly increased in the I/R model group and DS saponin intervention group. After DS saponin intervention, the AI was decreased from 40. 28 % in the I/R model group to 28. 45 % in the DS saponin intervention group (P＜0. 05). The expression of Bcl-2 mRNA in DS saponin intervention group and I/R model group was significantly decreased as compared with the sham operation group (P＜0. 05), but that of Bax mRNA was significantly increased in the I/R model group and DS saponin intervention group as compared with the sham operation group (P＜0. 05). After DS saponin intervention, the expression of Bcl-2mRNA was increased from 0. 25 in the I/R model group to 0. 391 (P＜0. 05), and that of Bax mRNA was decreased from 0. 565 in the I/R model group to 0. 473 (P＜0. 05). Conclusion DS extract saponin could significantly alleviate apoptosis in the I/R injury of renal grafts possibly by up-regulating the expression of Bcl-2 mRNA and down-regulating the expression of Bax gene.