Protection Against Oxidative Damage and Anti-Inflammatory Effect of Melatonin in Scalded Rats

The study aimed to evaluate the protective effects of melatonin against oxidative damage and inflammation in rats with deep partial thickness scalds. Thirty male Sprague-Dawley rats were divided into three groups: a sham group, a scald group, and a melatonin group, each containing 10 rats. The scald and melatonin groups were subjected to a 30% total body surface area (TBSA) partial thickness scald and received fluid resuscitation. The melatonin group was given an intraperitoneal injection of 10 mg/kg melatonin at 1 minute and 6 hours post-scald. At 12 hours post-scald, serum levels of malondialdehyde (MDA) and glutathione (GSH) were measured to assess oxidative damage, while tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) were measured by ELISA to evaluate inflammation. Additionally, apoptosis of hair follicle cells was assessed using the TUNEL method and caspase-3 immunohistochemistry. Results showed that the melatonin group had a 34% decrease in serum MDA, a 37% increase in GSH, and a 29% and 35% decrease in TNF-α and IL-1β, respectively, compared to the scald group. Furthermore, the apoptosis rate of hair follicle cells in the melatonin group was significantly lower than in the scald group. The study concluded that early administration of melatonin after a major thickness scald could reduce oxidative damage, decrease inflammation, and protect hair follicle cells.