高糖诱导人肾小球系膜细胞SGK的表达

目的　研究高糖环境中人肾小球系膜细胞(human mesangial cells, HMC) 中血清和糖皮质激素诱导的激酶(serum and glucocorticoid inducible kinase, SGK) 3种亚型SGK1、SGK2和SGK3的表达及意义。方法　将培养的HMC分为正常组(5 5 mmol/L D 葡萄糖)、高糖组(25 mmol/L D -葡萄糖) 和甘露醇对照组(19. 5 mmol/L甘露醇和5. 5 mmol/L D 葡萄糖)。采用RT PCR 方法检测SGK1、SGK2 和SGK3 mRNA 的表达, Western blot 方法检测SGK1蛋白的表达。结果　在高糖及甘露醇刺激下, HMC中SGK1、SGK2和SGK3 mRNA及SGK1 蛋白的表达明显上调(P<0. 05); 其中高糖上调SGK的表达明显高于甘露醇(P<0 .05)。结论　高糖能促进HMC的SGK1、SGK2 和SGK3mRNA及SGK1蛋白的表达, SGK1可能是高糖作用于HMC的细胞内信号通路中靶分子之一, 由它介导的高糖信号转导途径在糖尿病肾病的发生中可能起了重要作用。

Expression of SGK in Human Mesangial Cells Induced by High Glucose

Objective To investigate the effect of high glucose on serum and glucocorticoid-inducible kinase (SGK) mRNA and protein expression in human mesangial cells (HMC).Methods The cultured HMC were divided into 3 groups: normal group (5.5 mmol/L D-glucose),high glucose group (25 mmol/L D-glucose),mannitol control group (19.5 mmol/L mannitol and 5.5 mmol/L D-glucose). The expression of SGK_ 1,SGK_ 2 and SGK_ 3 mRNA was detected by semi-quantitative RT-PCR and the expression of SGK_ 1 protein by Western blot.Results The levels of SGK_ 1,SGK_ 2 and SGK_ 3 mRNA were elevated 2 h after high glucose stimulation and continued to be elevated at the end of 8 h. Mannitol could also increase the expression of SGK_ 1,SGK_ 2 and SGK_ 3 mRNA. High glucose and mannitol could also increase the SGK_ 1 protein at the end of 8-h stimulation. However,the effects of high glucose on SGK mRNA and SGK_ 1 protein level were stronger than mannitol.Conclusion High glucose can increase the expression of SGK_ 1,SGK_ 2 and SGK_ 3 mRNA and SGK_ 1 protein. The SGK_ 1 may be a target gene of high glucose in HMC,and SGK_ 1 may play a role in diabetic nephropathy by mediating the signaling pathway of high glucose in HMC.