Anti-inflammatory activity of an aqueous extract of Grewia tiliaefolia leaves

The leaves of Grewia tiliaefolia vahl. (Tiliaceae) have been used in vitiated conditions of pitta, kapha and burning sensation. It is one of such plants used in skin diseases, inflammatory bowel diseases, diarrhoea and pruritis. The aim of the present study was to evaluate the anti-inflammatory activity of an aqueous leaf extract of Grewia tiliaefolia (GT) in rodents using carrageenan, histamine and serotonin induced paw edema, prostaglandin inhibitory activity by castor oil induced diarrhoea, acetic acid induced capillary permeability, cotton pellet granuloma and sodium CMC induced leukocytes emigration tests. Results showed a dose dependent anti-inflammatory activity in carrageenan, histamine and serotonin induced paw edema at the dose of 250 and 500mg/kg. It also showed dose dependent prostaglandin inhibitory activity by preventing castor oil induced diarrhoea. The extract also exhibited dose dependent inhibition of vascular permeability induced by acetic acid; however it did not show any significant effect on growth of granuloma tissue. It also significantly reduced leukocyte counts at the dose of 500mg/kg. Phytochemical studies indicated the presence of tannins, phenolics and flavonoids. These findings suggest that the leaves of Grewia tiliaefolia possess anti-inflammatory activity in acute and subacute phase of inflammation, which may result from inhibition of prostaglandin synthesis, inhibition of inflammatory mediators, inhibition of increased vascular permeability and inhibition of leukocyte emigration into inflamed tissues.