Effects of Tea Polyphenols on Ni_2O_3-Induced Lipid Peroxidation in Rat Alveolar Macrophage and DNA Damage of HLF Cells

摘要

To study the effects of tea polyphenols (TP) on the injury of rat alveolar macrophages treated with Ni_2O_3. The alveolar macrophages were cultured in vitro with exposure to Ni_2O_3 (5mg/L). Meanwhile, TP (125, 250 and 500mg/L) were added in the media, respectively. The detection of malondialdehyde and activity of antioxidant enzyme in alveolar macrophages were carried out. The protective effects of TP against DNA damage of human lung fibroblasts (HLF) cells induced by Ni_2O_3 were also investigated. HLF cells were cultured in vitro and treated with Ni_2O_3 (5mg/L) and Ni_2O_3+TP (250mg/L), respectively. The single cell gel electrophoresis (SCGE) was used to detect the DNA breaks. The results showed that TP could increase the activity of superoxide dismutase in rat alveolar macrophages in a dose-dependent manner and inhibit significantly the production of malondialdehyde at dose of 250mg/L and 500mg/L compared with Ni_2O_3 group (p < 0.05). The level of DNA breaks induced by Ni_2O_3 was higher than the control group (P < 0.01). But the level of DNA breaks induced by Ni_2O_3+TP was lower than the Ni_2O_3 treated group (P < 0.01), which demonstrated that TP could prevent cells from DNA damage induced by Ni_2O_3.