Neuroprotective Outcome of Thymol against Global Cerebral Ischemia Reperfusion injury in Albino Rats

Abstract

Aims: The purpose of the present study was targeted to explore the possible role of thymol against global cerebral ischemia-reperfusion injury in albino rats. Study Design:  Healthy Albino Wistar rats (200–250 gm) were divided randomly into 5 groups (n=6).  Group I and II were considered as normal control and sham control, received 2% tween 80 orally, group III was ischemic- reperfusion (disease control) and received 2% tween 80 orally and Group IV and V received thymol at doses of 50 mg/kg, per oral and 100 mg/kg, per oral. respectively. Place and Duration of Study: Department of Pharmacology, Sri Padmavathi School of pharmacy, Tiruchanur, Tirupati in between Sept 2019 to March 2020. Methodology: Group I and II were considered as normal control and sham control, received  2% tween 80 orally, group III was ischemic- reperfusion (disease control) and received 2% tween 80 orally and Group IV and V received thymol at doses of 50 mg/kg, per oral (p.o) and 100 mg/kg, per oral (p.o). respectively. After pretreatment with thymol for 2 weeks, rats were subjected to bilateral common carotid artery occlusion for 1 hour accompanied by 22 hours reperfusion (I/R). After 22 hrs of reperfusion, motor coordination, hanging wire test, despair swim tests were studied. Antioxidant levels of reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and pro-oxidant level of Malondialdehyde (MDA) were analyzed in brain tissue homogenate. Changes in cerebral infarct size and histopathology were studied. Results: Pretreated groups of thymol (50 and 100 mg/kg p.o) showed significant improvement in neurobehavioral changes and attenuated oxidative damage as indicated by reduced LPO, restored GSH, SOD and CAT levels and decreased infract size when compared to ischemic reperfusion group. Conclusion: This study suggests that thymol may have a beneficial role against global ischemia reperfusion induced damage caused by excessive free radicals and behavioral alterations in rats.