PFT-α对高糖诱导的肾小球足细胞泛素化通路和细胞凋亡的影响

Effect of PFT-α on ubiquitin and apoptosis of podocyte injured by high glucose

目的:观察p53抑制剂(Pifithrin-alpha,PFT-α)对高糖刺激后肾小球足细胞泛素化通路和细胞凋亡的影响。方法:体外培养小鼠肾小球足细胞,分为对照组、高糖组(30 mmol/L葡萄糖)、甘露醇组(30 mmol/L葡萄糖+25 mmol/L甘露醇)、PFT-α组(30 mmol/L葡萄糖+10μmol/LPFT-α)、0.2%二甲基亚砜(Dimethyl sulfoxide,DMSO)溶剂对照组(30 mmol/L葡萄糖+0.2%DMSO)。用Western blot法检测各组足细胞p53和COP1蛋白的表达,TUNEL方法检测各组足细胞凋亡情况。结果:高糖刺激48 h后足细胞p53蛋白表达水平(1.210 8±0.035)较对照组(0.072 9±0.007 13)明显增加,COP1蛋白表达水平(0.579 6±0.041 9)则较对照组(1.067±0.053 4)下调;PFT-α在高糖刺激48 h后作用足细胞6 hp,53蛋白表达水平(0.166 4±0.038 7)较高糖组(1.210 8±0.035)下调,COP1蛋白表达水平(0.308 1±0.014 5)与高糖组(0.579 6±0.041 9)则差异无统计学意义;高糖刺激足细胞后凋亡率(35.41±3.31)%分别是对照组(2.23±0.17)%和PFT-α组(4.27±0.21)%的15.87倍和8.29倍,甘露醇组(42.44±6.11)%和0.2%DMSO组(32.80±5.02)%与高糖组差异无统计学意义。结论:高糖损伤肾小球足细胞时可能抑制小鼠肾小球足细胞泛素蛋白酶体活化,进而增加肾小球足细胞的凋亡,PFT-α可通过下调p53蛋白致小鼠肾小球足细胞凋亡减少。

Objective： To investigate the effect of pifithrin-a （PFY- ot ） on the ubiquitin and the apoptosis of podocytes by high glucose. Methods：Cultured mouse podoeytes were divided into normal group, high glucose group （30 mmol/L D-glucose）, mannital group （30 mmol/L D-glucose＋25 mmol/L mannital） ,PFF- a group（30 mmol/L D-glucose＋10 μmol/L PFF-ct ） and 0.2% DMSO group（30 mmol/L glucose＋0.2% DMSO）. The expressions of p53 and COP1 protein of each group were measured by Western blot. The apoptosis of podocytes was measured by TUNEL. Results： The expression of p53 in mouse podocytes by high glucose in 48 hours （ 1.2108 ± 0.035 ） was higher than that in the normal group （ 0.072 9 ± 0.007 13 ）, but the expression of COP1 （ 0.579 6 ± 0.041 9 ） was lower than that of normal group （ 1.067 ± 0.053 4 ）. After PFT- ot affected podocytes for 6 hours after high glucose, the expression of p53 in mouse podocytes（0.166 4 ± 0,038 7）was lower than that in the high glucose group （1.210 8±0.035）, the expression of COP1 （0.308 1 ＋ 0.014 5 ）was the same as high glucose group （ 0.579 6 ± 0.041 9 ） .The apoptosis of podocytes in high glucose group was（35.41 ± 3.31 ）% ,which was 15.87 times higher than that of normal group （2.23 ±0.17）% and 8.29 times higher than that of PFF- ot group （4.27 ± 0.21 ）% respevtively, mannital group （42.44±6.1 l ）% and 0.2% DMSO group（32.80 ± 5.02）% were the same as high glucose group. Conclusion：High glucose injured podocytes may inhibit the activity of ubiquitin proteasome and increase the apoptosis of mouse podocytes. PFTot can decrease the apoptosis through decreasing the expression of p53.