Investigation of Antistress Activity of Operculina Terpethum Roots using Various Experimental Models

Abstract

The root part of Operculina terpethum has been widely used in Ayurveda to treat variety of common and stress related disorders. The antistress effect of a seven-days treatment (100 and 200 mg / kg, p.o.) of the 80% ethanolic extract of Operculina terpethum root (OTRE) was evaluated by using the swimming endurance test, anoxic tolerance test, and biochemical changes in the cold-restraint stress test. The immunomodulatory activity was also evaluated for the same doses, and treatment of OTRE using the hem agglutination test. Diazepam 1 mg/kg was used as reference standard for the comparison. Both the doses of OTRE showed anti stress activity in all the tested models. 7 days pretreatment of OTRE (100 and 200 mg / kg, p.o.) treated animals showed a decrease in immobility time and an increase in anoxic tolerance time in swimming endurance and the anoxic tolerance tests, respectively. Pretreatment with OTRE significantly ameliorated the cold restraint stress induced variation in biochemical level such as increase in plasma cholesterol, triglyceride, glucose, total protein, and cortisol. Further, OTRE treatment significantly inhibited cold restraint stress induced alteration in brain noradrenaline, dopamine and serotonin levels. In mice immunized with sheep red blood cells, the treatment groups subjected to restraint stress prevented the humoral immune response to the antigen. The immune stimulating activity of the OTRE was indicated by an increase in the antibody titer in mice pre-immunized with sheep red blood cells and subjected to restraint stress. The findings of the present investigations indicate that the OTRE has significant anti stress activity, which may be due to the immune stimulating property and increased resistance, nonspecifically, against all experimental stress conditions.