Anti-infl ammatory and antinociceptive effects of the hydroethanolic extract of the flowers of Pyrostegia venusta in mice

Abstract

Pyrostegia venusta (Ker Gawl.) Miers, Bignoniaceae, is native to the Brazilian Cerrado and popularly known as "cipó-de-são-joão". In Brazilian folk medicine, the flowers of P. venusta are used as a general tonic and a treatment for diarrhea, vitiligo, cough, and common infections and inflammatory diseases of the respiratory system. Nevertheless, there are still no studies on its possible anti-inflammatory and antinociceptive effects. The P. venusta hydroethanolic extract (PvHE) was used to evaluate the anti-inflammatory and analgesic effects in carrageenan-induced paw edema, peritonitis induced by lipopolysaccharide, acetic acid-induced writhing, and formalin-induced paw-licking tests in Swiss male mice. PvHE at doses of 30-300 mg/kg p.o. demonstrated anti-inflammatory effect. PvHE reduced paw edema induced by carrageenan and inhibited leukocyte recruitment into the peritoneal cavity. The extracts showed antinociceptive activity in acetic acid-induced writhing and formalin tests. Our results showed that the PvHE demonstrated anti-inflammatory and antinociceptive action in mice. All the anti-inflammatory actions obtained are also suggested to due the presence of acacetin-7-O-β-glucopyranoside.