Bronchoprotective, Bronchodilatory and Anti-Inflammatory Activity of Ethanolic Extract from Woodfordia fruticosa (Kurz.) Flowers

The present investigation was aimed to investigate the bronchoprotective, bronchodilatory and anti-inflammatory effect of ethanol extract of Woodfordia fruticosa dried flower (WF-EE). WF-EE exhibited significant and dose dependent bronchoprotective, bronchodilatory and anti-inflammatory effect. WF-EE at 200 mg/kg prolonged the latent period and exhibited protection against experimental asthma induced by the combination of histamine and acetylcholine aerosol in guinea pigs. WF-EE (1 mg/ml) exhibited 100 % bronchodilation (complete bronchorelaxation) at concentrations 1.6 and 3.2 mg against acetylcholine and histamine induced contraction respectively. Administration of extract (100 or 200 mg/kg, p.o.) to rats showed significant inhibition of carrageenen as well as egg albumin induced paw edema. The anti-inflammatory effect of extract at 200 mg/kg was comparable to standard drug indomethacin (10 mg/kg, p.o.). Moreover, WF-EE has not shown any toxicity symptoms and mortality up to 2000 mg/kg, p.o. in rats, when evaluated for the acute toxicity study of WF-EE as per OECD guidelines. These results suggest the anti-asthmatic (bronchoprotective as well as bronchodilatory) and anti-inflammatory potential of WF-EE along with safety margin for oral administration.