Zingiber officinale Exhibits Neuroprotective Properties against Tramadol-Induced Spatial Memory Impairment and Histopathological Changes

Drug abuse has been on the increase in recent years. Tramadol is one of such drug commonly misused and reported to have neurotoxic effects. However, Zingiber officinale has been reported to have neuroprotective properties. This study aimed to evaluate the neuroprotective effects of Z. officinale on spatial memory deficits in tramadol-treated Wistar rats. Thirty adult male Wistar rats were divided into five groups, and respectively, orally administered the following for 21 days: the control group (2 ml/kg of distilled water), tramadol (Tram, 50 mg/kg), tramadol (50 mg/kg)+naltrexone (12.5 mg/kg), and tramadol (50 mg/kg)+Z. officinale (500 mg/kg+1000 mg/kg, respectively). A Morris water maze test was conducted for the assessment of spatial memory. The rats were euthanized by transcardiac perfusion, and the brains were harvested, fixed, and processed using haematoxylin and eosin stain for histology. A remarkable decrease in latency time and an increase in distance covered to locate the platform were observed in the tramadol-treated group compared to the control in the acquisition phase. The probe test showed a remarkable decrease in the time spent in the escape platform quadrant in the tramadol-treated group compared with the control. Neurodegenerative changes were observed in the hippocampus of the tramadol group, presenting as karyorrhexis, gliosis, and perineural vacuolation. These neurodegenerative changes were attenuated in Z. officinale-treated groups in a dose-dependent manner. Z. officinale improved the learning and memory of tramadol-treated rats. Findings from this study suggest that Z. officinale attenuated tramadol-induced neurotoxicity in Wistar rats