Objective:To investigate the effect of pifithrin-α(PFT-α)on the ubiquitin and the apoptosis of podocytes by high glucose.Methods:Cultured mouse podocytes were divided into normal group

high glucose group(30 mmol/L D-glucose)

mannital group(30 mmol/L D-glucose+25 mmol/L mannital)

PFT-α group(30 mmol/L D-glucose+10 μmol/L PFT-α)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-α 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 PFT-α group(4.27±0.21)% respevtively

mannital group(42.44±6.11)% 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.PFT-α can decrease the apoptosis through decreasing the expression of p53.