Role of Oxidative Damage Induced by Gamma Irradiation in Apoptosis of Intestinal Epithelial Cells

Objective To study the effect of oxidative damage induced by gamma irradiation on the apoptosis of intestinal epithelial cells, and provide a scientific basis for further clarifying relevant mechanism.

Methods Adult healthy rats were used to isolate and culture small intestinal epithelial cells and exposed under 0, 1, 6, 12, and 18 Gy ⁶⁰Coγ irradiation for 24 h. Apoptosis rate, reactive oxygen species(ROS), superoxide dismutase(SOD), catalase(CAT), glutathione(GSH), and glutathione peroxidase(GSH-px) were detected using corresponding kits.

Results The apoptosis rates of intestinal epithelial cells in the 6, 12, and 18 Gy groups were 7.03%, 14.87%, and 27.95%, respectively, higher than that in the control group(P < 0.05) and increasing with higher irradiation doses. Compared with the control group, the levels of ROS in intestinal epithelial cells of the 6, 12, and 18 Gy groups increased by 38.13%, 102.53%, and 215.08%, respectively, displaying a rising trend. The levels of GSH(by 10.26%, 55.77%, and 71.09%) and GSH-px(by 18.32%, 32.92%, and 60.99%) decreased with the increase of gamma ray dose. The levels of SOD in intestinal epithelial cells of the 1, 6, 12, and 18 Gy groups decreased by 20.18%, 42.46%, 59.04%, and 75.71%, and the levels of CAT decreased by 20.75%, 48.19%, 60.33%, and 71.15%, respectively, with statistical differences(P < 0.05).

Conclusion Gamma ray irradiation can initiate lipid peroxidation of tissues and cells, damage the antioxidant systems of intestinal epithelial cells, and accumulate ROS, which leads to cell oxidative stress, injury, and elevated apoptosis rate.