Evaluation of hydroalcoholic extract of Thyme on malondialdehyde, thiol, and glutathione peroxidase concentration in the Parkinson's model induced by 6-hydroxydopamine in adult male rats

Background: Parkinson's disease (PD) is a neuropathologic disorder caused by dopaminergic neurons degeneration in the dense part of the substantia nigra. Objective: The present study, designed to evaluate the effect of hydroalcoholic extract of thyme on malondialdehyde (MDA), thiol, and glutathione peroxidase (GPX) concentration in the PD induced by 6-hydroxydopamine in an animal model. Methods: In this experimental study, 40 male rats, were divided randomly into five groups (n=8) including control and PD group in which PD was induced by 4 µg 6-hydroxydopamine neurotoxin in medial forebrain bundle (MFB). Treatment groups received 100, 200 and 400 mg/kg thyme extract via intragastric administration for 14 days and then, the brains of the rats were extracted to evaluate lipid peroxidation and measure the levels of thiol (-SH) and GPX. Results: The significant increase in MDA concentration in the cerebral cortex, hippocampus, striatum (P< 0.05) and cerebellum (P< 0.001) and a significant reduction in thiol and GPX enzyme (P< 0.001) were reported in rats with PD. Treatment with thyme extract significantly increased thiol and GPX (P< 0.001) and significantly reduced MDA in the hippocampus, striatum (P< 0.001) and cerebral cortex (P< 0.01). Conclusion: Thyme extract showed potent antioxidant activity in an animal model of PD.