Protective effects of Genistein on human renal tubular epithelial cells damage of microwave radiation

Abstract

To observe the effects of microwave irradiation on human proximal renal tubular epithelial cells (HKC) and protec-tive effects of genistein. HKC cells were divided into control group, microwave irradiation group and genistein group(n=6) re-spectively. The genistein group cells were pre-incubated with 30μmol/L genistein in DMEM for 2 hours. After irradiation for 24 hours, the concentrations of lactate dehydrogenase(LDH) and β-N-acetyl glucosaminidase(NAG) in culture solution were measured to evaluate cell injury. Cells were curetted to measure the levels of malondialdehyde (MDA) and superoxide dismutase (SOD). Cell apoptosis and necrosis were de-tected with Hoechst 33258 stain. Compared with the control group, the NAG activity of the microwave irradiation group was signifi-cantly increased(P < 0.01), and NAG activity of genistein pre-incubated group was significantly decreased(P < 0.01). The levels of LDH in microwave irradiation group were also increased significantly (P < 0.01 vs control group). LDH levels could be decreased obviously (P < 0.01 vs microwave irradiation group) after genistein pre-incubate. Hoechst 33258 fluorescent staining revealed that the nucleus crimpled, cres-cent liked and chromatin condensed, even nucleus disintegrated. Our research showed that microwave irradiation could lead to large amount of cell apoptosis and necrosis, and genistein pre-treatment could reduce the ratio of apoptosis and necrosis than that in microwave irradiation group (P < 0.01). The concentration of MDA in microwave irradiation group was higher than that in control group (P < 0.01). At the same time, the activity of SOD was significantly reduced (P < 0.01). Pre-incubated with genistein could not decrease the MDA levels, but could increase the activities of SOD (P < 0.01 vs microwave irradiation group). microwave irradiation can induce human proximal renal tubular epithelial cells injury. The protective effects of genistein may partly correlated with decreasing oxidative stress damage and cell apoptosis in HKC cells.