In vitro ANTI-INFLAMMATORY AND ANTIOXIDANT EVALUATION OF AN INDIGENOUS MEDICINAL PLANT – Pterospermum rubiginosum

Abstract

The current study was carried out to determine the antioxidant potential, anti-inflammatory activity, and cellular viability of Pterospermum rubiginosum (PR), a tropical tree endemic to the Western Ghats. The antioxidant activities of the PR bark methanolic (PRME) and aqueous extract (PRAQ) were tested using ABTS as well as superoxide, nitric oxide, and hydroxyl radical assays. Total antioxidant activity was evaluated by adopting the colorimetric method and correlation with their antioxidant activities was derived by Pearson co-efficient analysis. The PRME showed the highest ABTS radical scavenging activity, EC50 (46.09µg/ml) followed by PRAQ (52.08µg/ml). Furthermore, the PRME exhibited the highest scavenging activity against superoxide, nitric oxide, and hydroxyl radicals. The MTT assay results revealed good cellular viability up to a concentration of 100µg/ml with an EC50 (106.869µg/ml). The inflammatory mediators such as Cox-2, IL-1β, IL-6, and NF-kB were reduced during the treatment of PRME in LPS stimulated RAW cells. The stress marker in rat liver cells such as glutathione reductase (GR), glutathione peroxidase (GPx), and reduced glutathione (GSH) levels was found in normal levels when compared to the untreated group of rats. The antioxidant enzyme superoxide dismutase and catalase also exhibited notable bioactivity in PRME treated groups up to a concentration of 1000µg/ml. The present study showed excellent In vitro and In vivo antioxidant activity; the potent anti-inflammatory ability of PRME in reducing the LPS induced inflammation in cell culture conditions.