Abstract

Background: Oxidative stress plays an important role in the pathogenesis of hypertension- induced cardiac hypertrophy. Plants are a rich source of antioxidant compounds. Thymol is a natural monoterpen phenol which is plentiful in some plants and shows many biological effects. The aim of the present study was to assess the effects of thymol on activity of antioxidant enzyme catalase, malondialdehyde (MDA) level and the activity of the inhibition of free radical DPPH (2,2-Diphenyl-1-picryl-hydrazyl), following left ventricular hypertrophy in rats.

Materials and Methods: In this experimental study, rats were divided into hypertrophied group without any treatment (H group) and rats pretreated with 25 and 50 mg/kg/day of thymol (Thy25+H and Thy50+H groups, respectively). Intact animals were served as control (Ctl). Animal model of left ventricular hypertrophy was induced by abdominal aortic banding. Serum catalase (CAT) activity, malondialdehyde (MDA) level and the activity of inhibition of free radicals DPPH were determined by the biochemical methods.

Results: In Thy25+H and Thy50+H groups, the CAT activity was increased significantly in serum (p<0.01, vs. Ctl). Also, serum level of MDA was decreased significantly compared to the group H in Thy25+H and Thy50+H groups (p<0.05 and p<0.001, respectively). The effect of inhibiting DPPH free radicals was increased significantly in Thy25+H and Thy50+H groups compared to the group H (p<0.001 and p<0.05, respectively).

Conclusion: The findings of this study suggest that thymol as an antioxidant causes cardioprotective effects and as well as prevents left ventricular hypertrophy via augmentation of serum antioxidant capacity.