Melatonin protect PC12 cells from hydrogen peroxide-induced damage via the Nrf2/HO-1 signaling pathway

Activation of reactive oxygen species (ROS) and oxidative stress play an important role in the pathogenesis of spinal cord injury (SCI). Melatonin (MT) has good antioxidant and anti-apoptotic effects. In this study, the oxidative stress model of adrenal pheochromocytoma cells (PC12) was established by hydrogen peroxide (H2O2) in order to evaluate the protective effect of MT on SCI model in vitro and its possible mechanism. PC12 cells were treated with H2O2 to establish cellular oxidative stress model. Cells were treated with different concentrations of MT (control group, 10uM MT + H2O2, 25uM MT + H2O2, 50uM MT + H2O2). Cell viability was detected by CCK-8. Intracellular ROS were detected by dichlorodihydrofluorescein diacetate, and apoptosis rate was detected by flow cytometry. Western blot and immunofluorescence were used to detect Nrf2, HO-1, SOD2, Prxd3, IL-1β, IL-18, iNOS protein expression. The results showed that MT could reduce H2O2-induced oxidative stress injury and cell apoptosis. MT inhibited the expression of IL-1β, IL-18, iNOS and promoted the expression of SOD2 and Prxd3. In addition, MT promoted Nrf2, HO-1 expression. In conclusion, MT pretreatment can protect H2O2-induced oxidative damage of PC12 cells through Nrf2/HO-1 signaling pathway.