Reduced ischemia‐reperfusion oxidative stress injury by melatonin and N‐acetylcysteine in the male rat brain

Middle cerebral artery occlusion (MCAO) is a model for inducing ischemic stroke in rodents, leading to devastating brain damage. Oxidative stress (OS) plays a crucial role in the pathogenesis of ischemia. In this study, the effect of melatonin and N-acetylcysteine on ischemia-reperfusion-induced oxidative stress injury in the cerebral cortex of male rats was investigated. 30 male Wistar rats were divided into sham, ischemic, NAC, melatonin and NAC + melatonin groups. All groups, except the sham group, underwent MCAO on the left side, and the treatment groups received intraperitoneal injections of either 50 mg/kg N-acetylcysteine (NAC) or 5 mg/kg melatonin or a combination of both 24 and 48 hours later. At 24 and 72 hours after surgery, the animals were examined for sensory and motor activity. The cerebral cortex was dissected after sacrificing the rats, infarct volume estimated and the concentrations of glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and nuclear factor erythroid-2 related factor 2 (Nrf2) were analyzed by enzyme-linked immunosorbent assay (ELISA). The results indicate that the NAC + melatonin group exhibited elevated sensory-motor activity and a reduced infarct volume rate in comparison to the ischemic group (p≤ 0.05). Compared to the ischemic group, the NAC + melatonin group showed a significant increase in SOD concentration and a significant decrease in MDA (p≤ 0.05). It can therefore be concluded that the simultaneous administration of NAC and melatonin can reduce the cerebral infarction volume, and improve neurological functions by modulating SOD and MDA.