Environ Exp Biol (2015) 13: 25–31

Anti-stress and nootropic activity of aqueous extract of Piper longum fruit, estimated by noninvasive biomarkers and Y-maze test in rodents

Abstract

Piper longum L., also known as long pepper or pipli, belongs to family Piperaceae. Fruits of this plant have been used traditionally to treat a variety of diseases. The current study was done to evaluate anti-stress activity in rats subjected to forced swim stress one hour after daily treatment of P. longum extract. Urinary vanillylmandellic acid, 5-hydroxyindoleacetic acid, homo vanillic acid and ascorbic acid, estimated by HPLC and spectrophotometric methods in all groups, were selected as non invasive biomarkers. Anti-stress and nootropic activity activities of aqueous extract of P. longum fruit extract were estimated as locomotor and working memory in rats in a Y-maze apparatus. The in vitro antioxidant activity was determined based on the ability of the P. longum to scavenge free radicals. Daily administration of aqueous extract of P. longum at doses of 100, 200 and 300 mg per kg body weight one hour prior to induction of stress increased the stress-induced urinary biomarker levels in a dose-dependent manner. P. longum treatment showed significant dose-dependent variation in non-invasive biomarker levels in urine samples of rats taken after 24 h. Cognition, determined by working memory and locomotor activity results, were shown to be dose-dependent. The results of this study suggest anti-stress and nootropic activity effect of P. longum in rodents.