Effect of dietary sesame oil as antioxidant on brain hippocampus of rat in focal cerebral ischemia Saif Ahmad a, ⁎ , Seema Yousuf a , Tauheed Ishrat a , M. Badruzzaman Khan a , Kanchan Bhatia b , Inayat Salem Fazli c , Jafar Salamat Khan d , Naseem Hasan Ansari e , Fakhrul Islam a, ⁎ a Neurotoxicology Laboratory, Department of Medical Elementology and Toxicology, Faculty of Science, Jamia Hamdard (Hamdard University), New Delhi 110 062, India b Department of Medical Elementology and Toxicology, Faculty of Science, Jamia Hamdard (Hamdard University), New Delhi 110 062, India c Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA d Council of Scientific and Industrial Research (CSIR), Ministry of Science and Technology, Govt. of India, Anusandhan Bhawan, Rafi Marg, New Delhi 110 001, India e Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas 77555–0647, USA Received 11 April 2006; accepted 13 June 2006 Abstract Oxidative stress may be regarded as an imbalance between free radical production and opposing antioxidant defenses. Free radical oxidative stress is implicated in rat cerebral ischemia and naturaceutical antioxidants are dietary supplements that have been reported to have neuroprotective activity. Many studies have reported dietary sesame oil (SO) as an effective antioxidant. In the present study the neuroprotective effect of dietary SO was evaluated against middle cerebral artery occlusion (MCAO)-induced cerebral ischemia injury in rats. Rats were fed on diet (20% SO) for 15 days. The middle cerebral artery of adult male Wistar rat was occluded for 2 h and reperfused for 22 h. The antioxidant properties of brain were measured as levels of reduced glutathione (GSH), glutathione-S-transferase (GST), glutathione peroxide (GPx), glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD) and thiobarbituric acid reactive substance (TBARS). A decrease in the activity of all the enzymatic and non-enzymatic antioxidants was observed along with an increase in lipid peroxidation (LPO) in MCAO group. The neurobehavioral activity of rats was also observed by using videopath analyzer. Dietary SO improved the antioxidant status in MCAO + SO group when compared with MCAO group. The results of neurobehavioral activity also support our biochemical data. The results obtained suggest protective effect of SO against cerebral ischemia in rat brain through their antioxidant properties. © 2006 Published by Elsevier Inc. Keywords: Dietary sesame oil (SO); Cerebral ischemia; Hippocampus; Oxidative stress; Antioxidant; Neurobehavioral activity Introduction In middle cerebral artery occlusion (MCAO)-induced cerebral ischemia, various biochemical events occur that cause intracel- lular calcium accumulation, depolarization, excessive release of excitatory amino acids, especially glutamate and inhibition of protein synthesis (Mies et al., 1993; Hossman, 1994). Cerebral ischemia is one of the leading causes for several neurological deficit and death (Chagnac-Amitai and Connors, 1989) and the causative mechanism suggested explaining this phenomenon is the involvement of reactive oxygen species (ROS) and oxidative stress (Traystman et al., 1991; Wang and Lo, 2003; Blomgren et al., 2003; Paradis et al., 2004). According to the literature, brain is very vulnerable to oxidative stress due to its high polyunsaturated fatty acids (PUFAs) content which are particularly susceptible to ROS damage (Cui et al., 2004; Halliwell, 2001). During ischemia, xanthine dehydrogenase undergoes irreversible proteolytic con- version to xanthine oxidase, producing superoxide and hydrogen peroxide in the presence of oxygen. Among the various free radicals produced, superoxide and hydroxyl radicals are potent in causing damage of cell membrane by inducing lipid peroxidation (Bromont et al., 1989). Although NO (nitric oxide) functions as an Life Sciences 79 (2006) 1921 – 1928 www.elsevier.com/locate/lifescie ⁎ Corresponding authors. Tel.: +91 11 26059688; fax: +91 11 26059663. E-mail addresses: saif_hamdard@yahoo.com (S. Ahmad), fislam2001@yahoo.co.in (F. Islam). 0024-3205/$ - see front matter © 2006 Published by Elsevier Inc. doi:10.1016/j.lfs.2006.06.017