Analgesic and Anti-Inflammatory Effects of an Extract of Fadogia agrestis in Rats

Abstract

Analgesic and anti-inflammatory activities of an aqueous extract produced from Fadogia agrestis (family Rubiaceae) stem bark were investigated using animal models. Significant dose-dependent increases in the reaction time in the tail-flick test and inhibition of writhing in the visceral pain test (i.p. injections of acetic acid) with P up to < 0.001, when compared with the control, were observed. In an anti-inflammatory investigation, we also found significant dose-dependent inhibitions in the carrageenan-induced paw edema and cotton-pellet granuloma tests. The extract in the highest non-sedative dose tested (200 mg/kg) demonstrated a potency comparable with that of a reference analgesic anti-inflammatory drug, acetyl salicylate (Aspirin, 100 mg/kg). Phytochemical screening revealed the presence of alkaloids and saponins in the extract. The relieving effects of Fadogia are probably mediated by the influences of active components of the extract on both central and peripheral nociceptive/ antinociceptive neural mechanisms. Therefore, our investigation explains the rationale behind the ethnomedicinal usage of the mentioned plant to relieve pain and inflammation, as claimed by local users, and shows that further studies of the mechanisms underlying the effects of the remedy tested are expedient.