Evaluation of anti–inflammatory and analgesic potential of methanol extract of Tectona grandis flowers

Abstract

To evaluate anti-inflammatory and analgesic activity of methanol extract of Tectona grandis (T. grandis) flowers (METGF) in animal models to support its traditional use. Acute toxicity study was performed to determine the toxicity level of METGF in mice and rats. Carrageenan (1% w/w) was administered and inflammation was induced in sub-plantar region of rat paw. Analgesia was induced by intraperitoneal injection of 0.6% v/v acetic acid in mice to assess peripheral analgesic action of METGF. Also, hot-plate was used to induce pain in mice to evaluate central analgesic action of METGF. Oral administration of METGF in rat and mice did not produce any toxicity at 2 000 mg/kg dose level. In carrageenan induced inflammation, administration of METGF (100 and 200 mg/kg) as well as indomethacin (10 mg/kg) reduced rat paw edema significantly at 3, 4 and 5 h. Both the doses of METGF showed significant inhibition in acetic acid induced writhing responses. In thermally induced analgesia models, administration of METG at dose of 100 and 200 mg/kg significantly increased reaction time compared to control animals. The preliminary phytochemical analysis revealed the presence of phenolic compounds and tannins in METGF. Present study, for the first time, confirms the anti-inflammatory and analgesic action of METGF and it supports the traditional use of T. grandis flowers.