敲低Txnip抑制高糖诱导的人肾小管细胞系凋亡

目的观察敲低Txnip对高糖诱导人肾小管上皮细胞凋亡的影响。方法将体外培养人肾小管上皮细胞分为正常糖组、高糖组、高糖+质粒载体对照组及高糖+shRNA组。采用原位末端转移酶标记技术(TUNEL)检测细胞凋亡;流式细胞术检测细胞ROS水平;Western blot检测caspase-3、cleaved caspase-3、BAX、BCL-2、P38 MAPK、P-P38 MAPK及细胞色素c的表达。结果与正常糖组相比,高糖组肾小管上皮细胞ROS产生和细胞凋亡明显增加(P0.01),cleaved caspase-3和P-P38 MAPK表达增高,BAX/BCL-2比率明显升高以及细胞色素c易位(P0.05)。敲低Txnip能够显著抑制高糖诱导的肾小管上皮细胞凋亡和ROS产生,下调cleaved caspase-3、和P-P38MAPK的表达,减少BAX/BCL-2比率和细胞色素c易位(P0.05)。结论敲低Txnip能够抑制高糖诱导的人肾小管上皮细胞凋亡可能是通过减少ROS产生,保护线粒体功能,抑制P38MAPK信号通路激活而实现的。

Txnip interference on HG-induced human kidney proximal tubular cell line apoptosis

Objective To investigate the effect of Txnip interference on high glucose (HG)-induced apoptosis in human kidney proximal tubular cell line (HK-2). Methods Cultured HK-2 were divided into normal glucose group（NG),high glucose group (HG), HG+contol plasmid vector(HG+C) and GH+ VDUP1 shRNA Plasmid (h) (HG+shRNA).Apoptosis of HK-2 was analyzed by DeadEnd? Fluorometric TUNEL System. ROS production was observed by flow cytometry. The expression levels of Txnip, caspase-3, cleaved caspase-3, Bax, Bcl-2, P38 MAPK, P-P38 MAPK and cytochrome c protein were observed by Western blot. The expression levels of Txnip, Bax, Bcl-2mRNA were observed by RT-PCR. Results Compared with normal glucose group (NG), the production of ROS, the number of cell apoptosis, the expression of cleaved caspase-3 and P-P38 MAPK, ratio of Bax/Bcl-2 and the release of cytochrome c from mitochondria to cytoplasm significantly increased in HK-2 in high glucose group (HG)(P<0.05). Txnip interference inhibited HG-induced ROS production, cell apoptosis, expression of cleaved caspase-3 and P-P38 MAPK, ratio of Bax/Bcl-2 and release of cytochrome c from mitochondria to cytoplasm in HK-2(P<0.05). Conclusions: Txnip interference can prevent HG-induced HK-2 apoptosis through decreasing ROS production, preserving mitochondrial function and inhibiting activation of P38 MAPK.