摘要
目的研究血清和糖皮质激素诱导的蛋白激酶1(SGK1)在高糖诱导人肾小球系膜细胞(HMC)产生纤连蛋白(FN)中的作用,探讨SGK1在糖尿病肾病(DN)肾小球硬化中的作用机制。方法将带有SGK1显性激活型突变体质粒(PIRES2EGFPS422DSGK1mutant,SD)瞬时转染HMC;同时,设空质粒(PIRES2EGFP,FP)转染组和未转染组(NT)为对照。分别用正常糖(NG,5.5mmol/LD葡萄糖)和高糖(HG,25mmol/LD葡萄糖)刺激8h后,采用RTPCR方法和Western印迹方法来观察SGK1和FN的mRNA及蛋白的表达。结果高糖环境下,转染SD的HMC与转染FP、NT组比较,其SGK1mRNA表达显著性增高(0.704vs0.497,0.491,P<0.01),SGK1蛋白过度活化(1178497vs193875,195597,P<0.01),其FNmRNA和蛋白的表达显著性的增加(0.749vs0.463,0.475,P<0.01;659550vs342354,340428,P<0.01)。结论在糖尿病肾病中,高糖可以通过SGK1介导的信号通路来诱导人肾小球系膜细胞增加合成FN,这种新发现的信号通路,表明SGK1可能参入糖尿病肾病肾小球纤维化的发生。
Objective To investigate the role of serum and glucocorticoid induced kinase-1 (SGK1) pathways in fibronectin(FN)synthesis in human mesangial cell (HMC) under high glucose condition and the mechanism by which SGK1 contributes to glomerulosclerosis in diabetic nephropathy (DN). Methods HMCs were cultured and transfected with PIRES2-EGFP-~ S422D SGK1 mutant (SD), plasmid containing SGK1 dominant activation mutant, or blank plasmid. Non-transfected HMCs were used as control group. Then the HMCs were divided into 6 groups: transfected with SD+high glucose (SD-HG, 25 mmol/L D-glucose), transfected with FP+high glues (FP+HG), non-transfected+high glucose (NT-HG), transfeted with SD+normal glucose (SD-NG, 5.5 mmol/L D-glucose), transfected with FP+normal glues (FP+NG), and non-transfected+normal glucose (NT-NG). Eight hours after the glucose stimulation, RT-PCR was used to examine the SGK1 mRNA expression and fibronectin (FN). Western blotting was used to detect the fibronectin (FN) protein expression. Results The SGK1 mRNA expression of the SD+HG group was 0.709, significantly higher than those of the FP+HG and NT+HP groups (0.497 and 0.491, both P<0.01). The SGK1 protein expression of the SD+HG group was 1 178 497, significantly higher than those of the FP+HG and NT+HP groups (193 875 and 195 597 respectively, both P<0.01). The FN mRNA expression of the SD+HG group was 0.749, significantly higher than those of the FP+HG and NT+HP groups (0.463 and 0.475 respectively, both P<0.01). The FN protein expression of the SD+HG group was 659550, significantly higher than those of the FP+HG and NT+HG groups (342 354 and 340 428 respectively, both P<0.01). There were not significant differences in the expressions of FN mRNA and protein among different NG groups. Conclusion SGK1 may be involved in the signal transduction leading to the increase of fibronectin production in DN and therefore may play an active part in glomerulosclerosis in DN.
出处
《中华医学杂志》
CAS
CSCD
北大核心
2005年第23期1591-1595,共5页
National Medical Journal of China
基金
国家自然科学基金资助项目(30270618)
关键词
糖尿病肾病
蛋白激酶类
肾小球膜
纤连蛋白类
Diabetic nephropathies
Protein kinases
Glomerular mesangium
Fibronectins
