活性维生素D_3对高糖诱导的人肾小管上皮细胞中α-SMA和FN表达的影响

Effects of 1,25-dihydroxy-vitamin D_3 on the expression of α-SMA and FN in high glucose induced renal tubular epithelial cells

目的探讨活性维生素D3(Vit D3)对高糖诱导的人肾小管上皮细胞(HK-2)中α-平滑肌肌动蛋白(α-SMA)和纤维连接蛋白(FN)表达的影响。方法培养人肾小管上皮细胞并分为正常组(N组,含5.5 mol.L-1D-葡萄糖)、高糖组(M组,含25 mol.L-1D-葡萄糖)、高糖+低浓度活性Vit D3组(LD组,含10-8mol.L-1活性Vit D3)和高糖+高浓度活性Vit D3组(HD组,含10-6mol.L-1活性维生素D3),细胞免疫组化方法测定各组细胞的α-SMA和FN的蛋白表达,RT-PCR半定量方法测定各组细胞的α-SMA和FN的mRNA表达。结果与N组比较,M组、LD组和HD组α-SMA、FN蛋白表达的水平和mRNA表达的水平明显升高(P<0.05),与M组比较,LD组和HD组α-SMA、FN蛋白表达的水平和mRNA表达的水平明显降低(P<0.05),其中,与LD组比较,HD组水平最低(P<0.05)。结论活性Vit D3可下调人肾小管上皮细胞α-SMA和FN的表达,从而抑制肾小管上皮细胞转分化,对糖尿病肾病有一定防治作用,且存在剂量依赖关系。

OBJECTIVE OBJECTIVE To investigate the effects of 1,25 - dihydroxy - vitamin D3 on the renal tubular epithelial cells expression of α-SMA and FN induced with high glucose. METHODS Cultured human renal tubular epithelial ceils were divided into four groups：group N, cultured with sugar（5.5 mmol·L^-1） ;group M,cuhured with 25 mmol·L^-1 glucose DMEM;group LD,cuhured with 25 retool·L^-1 glucose DMEM and 1,25 - dihydroxy - vitamin D3 of 10^-8mmol·L^-1; group HD, cultured with 25 mmol·L^-1 glucose DMEM and 1,25 - dihydroxy - vitamin D3 of 10^-6 mmol·L^-1, respectively. The expression of α- SMA and FN was detected with immuocytochemistry and RT - PCR at 48 hours. RESULTS Compared with group N, the expression of α - SMA and FN inereased significantly in group M, group LD and HD（P〈0.05 ）. Meanwhile, compared with group M,the expression of α - SMA and FN decreased significantly ill group LD and group HD P〈0.05 ） , especially in group HD. CONCLUSION 1,25 - dihydroxy - vitamin D3 can depress the expression of α- SMA and FN in renal tubular epithelial cells induced with high glucose, thus inhibit the transdifferentiation of renal tubular epithelial cells and lower the risk of diabetic nephropathy.