The Effect of Gallic Acid on Depression Symptoms, Oxidative Stress Markers and Inflammatory Cytokines in Rats’ Hippocampus After TMT Intoxication: An Experimental Study

  Trimethyltin (TMT) is an organotin which causes selective degeneration in hippocampus and leads to the appearance of depression in humans and rodents. The present study investigated the effect of Gallic acid (GA) on depression symptoms, oxidative stress markers and inflammatory cytokines functions in rats’ hippocampus after TMT intoxication. In this experimental study, 50 adult Wistar rats were randomly devided into 5 groups: Control, TMT+Saline, TMT+GA50, TMT+GA100, and TMT+GA200. 48 h after TMT intoxication, GA-treated groups received 50, 100 and 200 mg/kg of GA, and TMT+saline group received saline for 14 days. After evaluation of depression symptoms, the hippocampal levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), malondealdehyde (MDA), Tumor necrosis factor (TNF-α) and interleukin-1β (IL-1β) were measured by ELISA technique. Differences between the groups were analyzed by ANOVA with Tukey’s post hoc test. The results indicated an increase in the immobility time in the TMT+Saline group compared with the controls and a significant decrease in immobility time in the groups treated with high doses of GA (p˂0.001). GA treatment increased the function of antioxidant enzymes (SOD, CAT and GPX) and decreased MDA, TNF-α and IL-1β in comparison with the TMT+Saline group (p˂0.05). Administration of GA led to amelioration of depression symptoms caused by TMT intoxication through adjustment of inflammatory factors and reduction of oxidative stress.