Antinociceptive and Anti-Inflammatory Activities of Telfairia occidentalis Hydroethanolic Leaf Extract (Cucurbitaceae)

Telfairia occidentalis (Cucurbitaceae) is a tropical vine grown in West Africa as a leaf vegetable and for its edible seeds. The plant is noted to have healing properties. It is used as a blood tonic to revive weak/ill individuals and its use by sickle cell patients has been documented. In this study, the antinociceptive activity of the hydroethanolic leaf extract of Telfairia occidentalis (TO) was evaluated using the acetic acid-induced writhing, formalin, tail clip, and hot plate tests in mice. The carrageenan- and egg albumin-induced rat paw edema tests were used to evaluate the anti-inflammatory action. The extract (50-400mg/kg, p.o.) produced significant (P<.05) dose-dependent inhibition of pain response elicited by acetic acid and formalin while also increasing the nociceptive reaction latency in the tail clip and hot plate tests. In respect of anti-inflammatory activity, the extract elicited significant (P<.05) time and dose-dependent inhibition of edema development in the carrageenan and egg albumin tests. Peak effects of TO in the models were generally comparable with the effects of the standard drugs (acetylsalicylic acid, morphine, indomethacin, and chlorpheniramine) used. Phytochemical screening of the extract revealed the presence of tannins, saponins, phlobatannins, and anthraquinones. The extract did not produce any mortality and visible signs of delayed toxicity when administered orally up to 2000mg/kg. The LD50 (i.p.) was estimated to be 4073.80mg/kg. The results obtained in this study suggest that TO possesses antinociceptive and anti-inflammatory activities possibly mediated through peripheral and central mechanisms involving inhibition of release and/or actions of vasoactive substances and prostaglandins.