Effect of hydrogen on expression of nuclear factor E2-related factor 2 during endotoxin-induced oxidative injury to macrophages

Abstract

Objective To evaluate the effect of hydrogen on the expression of nuclear factor E2-related factor 2(Nrf2)during endotoxin-induced oxidative injury to macrophages. Methods Normally cultured Raw264.7 cells were divided into 4 groups(n=36 each)using a random number table: control group(group C), hydrogen-rich saline group(group H), endotoxin group(group E)and endotoxin plus hydrogen-rich saline group(group EH). In E and EH groups, endotoxin was added with the final concentration of 1 μg/ml.Hydrogen-rich saline(hydrogen concentration 0.06 mmol/L)was added in H and EH groups.All the cells were incubated for 48 h. At 6, 24 and 48 h of incubation, cells were collected to detect the activity of reactive oxygen species(ROS), and cells were collected and proteins extracted for determination of superoxide dismutase(SOD)and catalase(CAT)activities and Nrf2 expression by Western blot. Results Compared with group C, the ROS activity was significantly increased, the levels of SOD and CAT were significantly decreased, and the expression of Nrf2 was significantly up-regulated in E and EH groups(P 0.05). Compared with group E, the ROS activity was significantly decreased, the levels of SOD and CAT were significantly increased, and the expression of Nrf2 was significantly up-regulated in group EH(P<0.05). Conclusion Hydrogen can attenuate endotoxin-induced oxidative injury to macrophages, and the mechanism may be related to up-regulated expression of Nrf2. Key words: Hydrogen; Endotoxins; Macrophages; Oxidative stress