IN VIVO ANTIPLASMODIAL AND IMMUNOMODULATORY ACTIVITIES OF ETHANOLIC EXTRACT OF VERNONIA AMYGDALINA DEL. LEAVES

Abstract

The in vivo antiplasmodial and immunomodulatory properties of ethanolic extract from Vernonia amygdalina leaves were studied. Ethanolic extract of the plant was prepared from air-dried leaves using standard procedures. For quality validation, chemical finger-print of the extract was performed through high performance thin layer chromatography (HPTLC). Extract was evaluated in vivo for antiplasmodial activity by the standard four-day suppressive test on P. berghei (ANKA) infected male Swiss mice (six weeks old) divided into five groups of six animals each. The absorption spectra from the HPTLC chemical fingerprint of the extract revealed several peaks suggesting presence of some compounds. Results from the in vivo study showed that the ethanolic extract of the plant leaves was significantly active against P. berghei in a dose-dependent manner with minimum and maximum activity observed in mice treated orally with 100mg/kg (% inhibition = 23.7%) and 1000 mg/kg (% inhibition = 82.3 %) of the extract, respectively, on day four of the study. There was also a dose-dependent decrease (p<0.05) in some oxidative stress indices especially nitric oxide and lipid peroxidation levels in the extract treated groups as against the infected controls which had high levels of these parameters. The pro-inflammatory cytokines (TNF-? and IFN-?) levels were considerably low in the extract treated groups relative to the infected controls. The results suggest that ethanolic extract of V. amygdalina leaves was