Antinociceptive Effect ofTephrosia sinapouExtract in the Acetic Acid, Phenyl-p-benzoquinone, Formalin, and Complete Freund’s Adjuvant Models of Overt Pain-Like Behavior in Mice

Abstract

Tephrosia toxicaria, which is currently known asTephrosia sinapou(Buc’hoz) A. Chev. (Fabaceae), is a source of compounds such as flavonoids.T. sinapouhas been used in Amazonian countries traditional medicine to alleviate pain and inflammation. The purpose of this study was to evaluate the analgesic effects ofT. sinapouethyl acetate extract in overt pain-like behavior models in mice by using writhing response and flinching/licking tests. We demonstrated in this study thatT. sinapouextract inhibited, in a dose (1–100 mg/kg) dependent manner, acetic acid- and phenyl-p-benzoquinone- (PBQ-) induced writhing response. Furthermore, it was active via intraperitoneal, subcutaneous, and peroral routes of administration.T. sinapouextract also inhibited formalin- and complete Freund’s adjuvant- (CFA-) induced flinching/licking at 100 mg/kg dose. In conclusion, these findings demonstrate thatT. sinapouethyl acetate extract reduces inflammatory pain in the acetic acid, PBQ, formalin, and CFA models of overt pain-like behavior. Therefore, the potential of analgesic activity ofT. sinapouindicates that it deserves further investigation.