Adaptogenic and nootropic activities of aqueous extract of Carum carvi Linn. (Caraway) fruit: An experimental study in Wistar rats

Abstract

In the present investigation the aqueous extract of Carum carvi was evaluated for antistress activity in normal and stress induced rats. The extract was studied for nootropic activity in rats and in vitro antioxidant potential to correlate its antistress activity. For the evaluation of antistress activity groups of rats were subjected to forced swim stress one hour after daily treatment of Carum carvi extract. Urinary vanillylmandelic acid (VMA) and ascorbic acid were selected as non invasive biomarkers to assess the antistress activity. The 24 h urinary excretion of vanillylmandelic acid (VMA) and ascorbic acid was determined in all groups under normal and stressed conditions. The nootropic activity of the extract as determined from acquisition, retention and retrieval in rats was studied by conditioned avoidance response using Cook’s pole climbing apparatus. The in vitro antioxidant activity was determined based on the ability of Carum carvi to inhibit lipid peroxidation in liver and brain homogenates. Daily administration of Carum carvi at doses of 100, 200 and 300 mg/kg body weight one hour prior to induction of stress inhibited the stress induced urinary biochemical changes in a dose dependent manner. However no change in the urinary excretion of VMA and ascorbic acid was observed in normal animals at all the doses studied. The cognition, as determined by the acquisition, retention and recovery in rats was observed to be dose dependent. The extract produced significant inhibition of lipid peroxide formation in comparison with ascorbic acid in a dose dependent manner in both liver and brain. The present study provides scientific support for the antistress (adaptogenic), antioxidant and nootropic activities of Carum carvi extract and substantiates its traditional use as a culinary spice in foods as beneficial and scientific in combating stress induced disorders.