普伐他汀对高糖培养肾小球系膜细胞细胞外基质产生和氧化应激的影响

目的探讨普伐他汀对糖尿病肾病的保护机制。方法大鼠肾小球系膜细胞分别用正常浓度葡萄糖(5.5 mmo.lL-1),高浓度葡萄糖(25 mmo.lL-1)及葡萄糖25 mmo.lL-1+普伐他汀100μmo.lL-1培养。用CCK-8试剂盒测定细胞增殖,比色法检测培养液中超氧化物歧化酶(SOD)活性、谷胱甘肽(GSH)和丙二醛(MDA)含量。ELISA法检测培养上清液Ⅳ型胶原(ColⅣ-)、纤连蛋白(FN)、转化生长因子β1(TGFβ-1)和基质金属蛋白酶组织抑制因子(TIMP-1)含量;明胶酶谱法检测培养上清明胶酶A及B的活性。结果与对照组比较,高糖组肾小球系膜细胞增殖增加,基质蛋白ColⅣ-和FN合成增多,明胶酶A及B活性下降,TIMP-1含量和TGFβ-1分泌增加,总SOD活性和Cu,Zn-SOD活性下降,GSH含量下降,MDA含量增加。与高糖组比较,普伐他汀干预后可逆转上述变化。结论普伐他汀可抑制高糖培养的肾小球系膜细胞增殖,减少胞外基质合成,增加胞外基质降解,并缓解高糖诱导的氧化应激。

Effects of pravastatin on production of extracellular matrix and oxidative stress of glomerular mesangial cells incubated with high concentration of glucose

AIM To investigate the protection mechanism of pravastatin on diabetic nephropathy. METHODS Rat mesangial cells were incubated in media containing 5.5 mmol·L^-1 glucose(control), 25 mmol·L^-1 glucose(high glucose) and 25 mmol·L^-1 glucose+100 μmol·L^-1 pravastatin, respectively. Cell proliferation was assessed with CCK-8 kit, and the activity of superoxide dismutase (SOD), contents of malondialdehyde (MDA) and glutathione (GSH) in supernatant were assayed using chromatometry. Synthesis of fibronectin (FN), type Ⅳ collagen (Col-Ⅳ), transforming growth factor-β₁ (TGF-β₁) and tissue inhibitor of matrix metalloproteinase-1(TIMP-1) in supernatant were determined with ELISA. The activities of matrix metalloproteinases (gelatinases A and B) in supernatant were determined by gelatinase zymography. RESULTS Compared with control group, mesangial cells cultured with high-glucose showed a high growth rate, increased synthesis of Col-Ⅳ and FN, decreased activities of gelatinases A and B, and increased secretion of TGF-β₁ and TIMP-1. High- glucose significantly reduced GSH level, decreased activities of total SOD and Cu, Zn-SOD, and elevated MDA level. Compared with high glucose group, these changes could be reversed by pravastatin treatment. CONCLUSION Pravastatin inhibits proliferation of mesangial cells, decrease synthesis of extracellular matrix, increase degradation of extracellular matrix, and attenuate oxidative stress induced by high glucose.