Cissampelos pareira Linn. ameliorates thyroxin-induced cardiac hypertrophy in rats.

Ethnopharmacological Relevance: Cissampelos pareira extract has been traditionally used in ayruveda as cardiotonic, diuretics and in heart complains but its pharmacological evaluation in thyroxin-induced cardiac hypertrophy has not yet been explored.

Aim Of The Study: The aim of this study was to assess the cardioprotective effect of C. pareira root extract in experimentally induced hyperthyroidism in rats.

Materials And Methods: Male Wistar rats were treated with (i) thyroxin (0.1 mg/kg/day, i.p.) for 30 days, (ii) C. pareira extract (200 mg/kg/day, p.o.) alone for 60 days, (iii) C. pareira extract (100 and 200 mg/kg/day, p.o., respectively) for 30 days then with thyroxin for another 30 days, (iv) thyroxin for 30 days then C. pareira extract (100 and 200 mg/kg/day, p.o., respectively) for another 30 days. At the end of experiment, serum calcineurin, nitric oxide, lactate dehydrogenase, and thiobarbituric acid reactive substance as well as serum and/or myocardial antioxidant enzymes activity were estimated.

Results: Hyperthyroid induced cardiotoxicity was characterized by a significant (P<0.001) increase in heart weight/body weight ratio, serum calcineurin, nitric oxide, lactate dehydrogenase and thiobarbituric acid reactive substance levels as well as a significant decrease in serum reduced glutathione, myocardial glutathione peroxidase, glutathione reductase and glutathione-S-transferase levels, which were significantly (P<0.05 and P<0.01) reverted by C. pareira extract treatment. Reversal of histological changes on treatment with C. pareira extract was also supported the biochemical parameters. These results were quite comparable with amlodipine, the standard drug taken in this study.

Conclusions: Treatment with C. pareira extract ameliorates thyroxin-induced oxidative stress and cardiac hypertrophy, probably through amelioration of calcineurin activity and augmentation of antioxidant enzyme activities.