Effect of ulinastatin on oxidative stress injury to myocardial cells in diabetic rats in vitro

Objective To evaluate the effect of ulinastatin on oxidative stress injury to myocardial cells in diabetic rats in vitro. Methods The H9c2 cells were cultured in DMEM culture medium and the cells at the logarithmic growth phase were seeded in 96-well plates(density 1×104 cells/ml, 200 μl/well)or in 6-well plates(density 1×105 cells/ml, 2 ml/well). The cells were randomly divided into 4 groups(n=18 each)using a random number table: normal control group(group C), high-glucose group(group HG), high-glucose + oxidative stress group(group HG+ OS), ulinastatin + high-glucose+ oxidative stress group(group U+ HG+ OS). The cells were cultured in high-glucose DMEM culture medium(25.0 mmol/L)for 48 h in group HG.After the cells were cultured in high-glucose DMEM culture medium for 24 h, H2O2 with the final concentration of 500 μmol/L was added to the high-glucose culture medium, and the cells were continuously cultured for 24 h in HG+ OS and U+ HG+ OS groups.In group U+ HG+ OS, ulinastatin 400 U/ml was added to the high-glucose culture medium.The cells were collected for determination of cell viability, H9c2 apoptosis, activity of superoxide dismutase(SOD)and contents of malonadehyde(MDA). Apoptosis rate was calculated.The cell culture supernatant was collected for detection of lactate dehydrogenase(LDH)activity. Results Compared with group C, the cell viability and SOD activity were significantly decreased, and the apoptosis rate, MDA content and LDH activity were increased in the other groups.Compared with HG group, the cell viability and SOD activity were significantly decreased, and the apoptosis rate, MDA content and LDH activity were increased in HG+ OS and U+ HG+ OS groups.Compared with group HG+ OS, the cell viability and SOD activity were significantly increased, and the apoptosis rate, MDA content and LDH activity were decreased in group U+ HG+ OS. Conclusion Ulinastatin can mitigate oxidative stress injury to myocardial cells in diabetic rats, and inhibited cell apoptosis is involved in the mechanism. Key words: Trypsin inhibitors; Diabetes mellitus; Oxidative stress