EVALUATION OF NEUROBEHAVIOURAL AND BIOCHEMICAL EFFECTS OF THE ETHANOL EXTRACT OF Afzelia africana STEM BARK IN ROTENONE-INDUCED PARKISONISM IN RODENTS

Parkinson’s disease is a neurodegenerative disease that occurs due to progressive loss of dopaminergic neuron resulting in motor dysfunction with symptoms such as bradykinesia, akinesia and non-motor symptoms such as anxiety and cognitive deficits. Experimental models using neurotoxins such as rotenone mimic the features of Parkinson’s disease. Afzelia africana, a medicinal plant with antioxidant and anti-inflammatory properties has shown potential neuroprotective properties. The purpose of this study is to evaluate the biochemical and behavioural effects of Afzelia africana in rotenone-induced Parkinsonism using catalepsy and beam walking. Phytochemical screening of the stem bark of Afzelia africana was conducted to determine the bioactive phytoconstituents present and acute toxicity studies was done to determine the safety profile of the plant. Rats randomly divided into different groups viz: no treatment, vehicle only, rotenone plus vehicle, rotenone plus 250 mg/kg of stem bark extract, and rotenone plus 500 mg/kg of stem bark extract were used for the study. These were treated daily with either the vehicle or two doses of Afzelia africana. Rats subject to rotenone treatment received rotenone on days 1,4,7 and 10 of the study. Catalepsy and beam walking were conducted to assess motor performance on days 0, 5 and 10. Animals were sacrificed on the 11 th day and organs harvested for biochemical analysis. The mean lethal dose of Afzelia africana was estimated to be greater than 5000 mg/kg. Afzelia africana at doses used in this study reduced the cataleptic score and increased time spent in the beam walking. Treatment with A, africana reduced rotenone elevated levels of alanine transaminase, alkaline phosphatase, aspartate transaminase in the livers of test animals. A. africana also reduced urea and creatinine levels increased by rotenone. Findings from this that the ethanol extract of Afzelia africana has nephroprotective and hepatoprotective potential.