Ameliorative effect of <i>Vernonia amygdalina</i> on lead-induced neurotoxicity on the premotor cortex of adult Wistar rats

BACKGROUND AND AIM: Lead toxicity affects different body systems including the nervous system, resulting in brain damage, neuromuscular weakness, and impaired cognitive functions. This study evaluated the ameliorative effect of aqueous leaf extract of Vernonia amygdalina (AEVA) on lead acetate-induced neurotoxicity of the premotor cortex of adult Wistar rats. METHODOLOGY: Thirty adult male Wistar rats were divided into six groups of five each. The rats were accessed for neurobehavioral studies using a foregrip strength test apparatus. Group I received 1ml/kg body weight of distilled water. Group II received only 120 mg/kg body weight of lead acetate. Group III received 120 mg/kg body weight of lead acetate for 1 week and 2 weeks of natural recovery. Group IV received 120mg/kg body weight of lead acetate and 10mg/kg body weight of Succimer. Group V and VI received 120mg/kg body weighr of lead acetate with 1000mg/kg, and 1500mg/kg body weight of AEVA respectively. Administration lasted for 21 days. At the end of the experimentation, the rats were euthanized and brains harvested for oxidative stress, and histological (H&E) assessments. RESULTS: A decrease in muscular strength of Wistar rats treated with lead acetate was observed, however, improvement was seen in all the treatment groups, although, it was statistically significant Oxidative stress was induced in rats exposed to lead acetate as indicated by decreased superoxide dismutase, and catalase respectively. However, 1500mg/kg AEVA treatment ameliorated these changes with a significant increase. The results revealed histopathological changes such as karyorrhexis, cytoplasmic vacuolations, pyknosis and karyolysis in the premotor cortices of lead acetate-exposed rats which were ameliorated when treated with AEVA at 1000 and 1500 mg/kg body weight. CONCLUSION: This study therefore concludes that aqueous leaf extract of Vernonia amygdalina ameliorated lead-induced neurotoxicity of the premotor cortex of adult Wistar rats, and may be beneficial to people living in lead endemic areas.