Improvement of memory and neurological deficit with Ocimum basilicum L. extract after ischemia reperfusion induced cerebral injury in mice
Oxidative stress is strongly implicated in the pathogenesis of stroke. Strategies using antioxidants to improve neurological functions after stroke have, thus, gained significant attention. Ocimum basilicum L. is used traditionally to treat CNS disorders. Its antioxidant capacity is well established. Our laboratory has reported protective effects of pre-treatment with O. basilicum in experimental stroke, but its curative (post-treatment) effects in ischemic stroke have not been documented. Hence, the present study was aimed to evaluate the effect of O. basilicum leaf extract (OBLE) on functional outcomes following cerebral injury in mice. Cerebral injury was induced in the experimental animals by bilateral common carotid artery occlusion (BCCAO) followed by reperfusion. OBLE treatment (200 and 400 mg/kg; orally, once daily) was given for 7 days after BCCAO. Cognitive outcomes and sensorimotor disturbances were evaluated with Morris Water Maze, Elevated Plus Maze and neurological severity score, respectively. TTC (2,3,5-triphenyltetrazolium chloride) staining was used to measure cerebral infarct size. Thiobarbituric acid reactive substances, reduced glutathione levels and superoxide dismutase activity in mice brain homogenate were estimated to elucidate the neuroprotective mechanism of OBLE. Treatment with OBLE resulted in marked improvement in memory and motor coordination. OBLE also decreased cerebral infarct size and oxidative stress in mice. The extract was standardised with respect to total phenol content; an HPLC-PDA analysis showed the presence of eight phenolic acids in OBLE. It is concluded that treatment with OBLE improves functional outcomes after ischemic stroke and this may be developed as a neuroprotective drug.
KeywordsCerebral injury Functional deficit Neuroprotection Ischemic stroke Ocimum basilicum extract Phenolic acids
The authors would like thanks University Grants Commission, New Delhi, India for providing UGC-BSR research fellowship (No.F.7-265/2009(BSR)) to Mr. Varinder Singh to carry this research work. The authors are also thankful to Prof. Nirmal Singh, Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala, Punjab, India for providing lab facilities and guidance for pharmacological studies.
Compliance with ethical standards
The experimental protocol was approved by Institutional Animal Ethics Committee (approval no. 107/99/CPCSEA/2015–09) and is in accordance with the guidelines of the Committee for the Purpose of Control and Supervision of Experiments on Animals (CPCSEA), Ministry of Environment and Forest, Government of India.
Conflict of interest
The authors declare that they have no conflict of interest.
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