Cola acuminata Mitigates Cognitive Deficit and Oxidative Stress in Mercury Chloride-induced Neurotoxicity in Male Wistar Rats

Abstract

Cola acuminata is used in traditional medicine for the management of memory impairment and other neurodegenera-tive conditions. This study investigated the effects of Cola acuminata aqueous leaves extract (ALECA) on mercury chloride-induced neurotoxicity in Wistar rats. Twenty male Wistar rats weighing between 160 and 210 g were randomly assigned to four groups (n = 5). The control group received 0.5 mL of distilled water; the mercury chloride (HgCl2) group received HgCl2 (5 mg/kg b.w.); the ALECA100 and ALECA300 groups received ALECA (100 and 300 mg/kg b.w., respectively), followed by the administration of HgCl2 (5 mg/kg b.w.) for two weeks. The rats were subjected to behavioural tests in the Morris water maze and light and dark field box. The rats were then sacrificed to obtain their brains, which were homogenized for biochemical assays of acetylcholinesterase (AChE), malondialdehyde (MDA), total protein (TP), and glutathione (GSH) using standard methods. The results revealed a significant increase in escape latency, a significant decrease in probing frequency and brain GSH, and a significant (p<0.05) increase in brain MDA and TP levels and AChE activity in the rats exposed to HgCl2. However, administration of either 100 or 300 mg/kg ALECA protected against memory impairment with a significantly reduced escape latency, increased probing frequency and brain GSH, and decreased (p<0.05) MDA, TP and AChE. This study concludes that ALECA mitigated HgCl2-induced neurotoxicity via reduction of oxidative stress and enhanced cholinergic functions