Ethanolic Stem Bark Extract of Khaya Senegalenesis Ameliorates Cerebral Ischemia in Wistar Rats

Khaya senegalenesis is the most popular African medicinal meliaceous plants used traditionally in the management of neurodegenerative disorders. This study aimed to investigate the neuroregenerative effects of Khaya senegalenesis bark extract on cerebral ischemia in adult wistar rats. Twentyfive adult wistar rats weighing 300-400 g were randomly divided into five groups (each n=5), and in 2 phases of experiment. Phase 1 stroke induction (group B - E) and phase 2, treatment (group D & E) at low and high doses of 150 mg/kg and 250 mg/kg body weight of Khaya senegalenesis. 4 groups (groups B - E) were stroke induced by occlusion of middle cerebral artery through incision of the cervical region. Group A were control, administered distilled water, group B, stroke-induced and evaluation, group C, stroke-induced and untreated to assess recovery, group D and E, stroke-induced and treated. At the end of 2 weeks, the animals were sacrificed by cervical dislocations, blood sample collected to measure marker of oxidative stress, serum electrolytes and the brain tissues were perfused with phosphate buffer solution, harvested, processed and stained with H& E for histological observation. Normal histoarchitecture of cerebral cortex observed in control (group A) while group B revealed intact meninges, with congested meningeal vessels, mild tissue gliosis, lymphocytic infiltrates, show cerebral ischemia induced expression. Group C shows intact meninges, with moderate to severe lymphocytic infiltrates, vascular congestion, mild tissue oedema and gliosis. On treatment, low dose of Khaya senegalenesis shows minimal cellular proliferation and moderate gliosis while there was marked improvement in neurovascular unit in Khaya senegalenesis high dose. SOD, GSH, Na+ and K+ significantly decrease while MDA increase significantly in stroke induced rats. In the treated groups, SOD, GSH, Na+ and K+ values significantly increase while MDA significantly decrease. A dose of 250 mg/kg body weight of Khaya senegalenesis ethanol stem bark extract has been shown to ameliorate induced degenerative changes in the cerebral cortex causes by stroke-induced adult wistar rats.

Key Words: Cerebral ischemia, Cerebral cortex, Khaya senegalenesis, Neurovascular unit