The protective effect of Carica papaya and vitamin E on ischaemic-reperfusion insult of rat brain following bilateral occlusion of common carotid artery

Abstract

Introduction: Ischaemic stroke is a leading cause of death and neurological disability. Stroke models in animals attempt to mimic the events in human. This study investigated the possible neuroprotective effect of Carica papaya leaf aqueous extract (CPAE) and vitamin E on induced ischaemic-reperfusion injury from bilateral common carotid artery occlusion (BCCAO) in rat’s brain. Materials and methods: Thirty-five female rats were randomly assigned into one of five groups (n=7): Control (1 mL distilled water); CPAE (500 mg/kg); BCCAO; BCCAO + CPAE (500 mg/kg); BCCAO + VIT E (500 mg/kg). BCCAO was carried out on day 21 for 30 minutes followed by 24 hours of reperfusion, while CPAE was administered daily for 21 days. Behavioural tests were done on day 22 after which rats were euthanized and biochemical and histological changes were assessed. Results: The BCCAO produced significant (p<0.05) elevation in lipid peroxidation and reduced glutathione levels while increasing superoxide dismutase and catalase activities. It also significantly reduced the number of lines crossed, rearing, duration of forelimb grip but increased duration of negative geotaxis. It induced scattered pyknotic neurons in cerebral cortex and pyramidal neurons in the CA1 subfield of the hippocampus. Pretreatment with CPAE and vitamin E improved oxidative, behavioural response and histological alterations of the neurons in both cerebral cortex and CA1 subfield of the hippocampus. Conclusion: The results support a protective role for CPAE and vitamin E on acute ischaemia/reperfusion injury induced by BCCAO in rats, thus contributing to the continuous search for neuroprotective strategies in stroke.