Chimie médicale

In Vivo and In Vitro Anti-trypansomal Evaluation of Crude Methanolic Extracts of Crotalaria albicaulis and Cistanche phelypaea against Trypanosoma evansi

Abstract

Markos Tadele, Getachew Alebie and Yitagesu Tewabe

Camel trypanosomiasis is a major disease of economic importance in Ethiopian Somali Regional State, Ethiopia. Local people use the leaves of Crotalaria albicaulis and Cistanche phelypaea to treat this disease and complement the absence or the limitations of existing anti-trypanosomal chemotherapeutic agents. Thus, the aim of this study was to evaluate the in vivo and in vitro anti-trypanosomal activity of the methanolic crude extracts of leaves of Crotalaria albicaulis and Cistanche phelypaea against Trypanosoma evansi isolate. The fresh leaves of both plants were extracted by percolation technique using methanol. For the in vivo assay, mice infected with T. evansi were administered intraperitoneally daily for 7 days with crude extracts at doses of 100, 200 and 400 mg/ kg body weight. In vitro trypanocidal activity of these extracts was tested in triplicate in 96 well micro titer plates. Diminazene aceturate and dimethyl sulfoxide were used as positive and negative controls, respectively. At 4.0 mg/ ml concentration the methanolic crude extract of C. albicaulis completely ceased motility of the parasite after 40 minutes. The plant also significantly (p<0.05) prolonged infection period in vitro infectivity test. Moreover, at 400 mg/kg dose, the crude extracts of both plants exhibited a mild in vivo anti-trypanosomial activity against T. evansi. This study established that leaves of C. albicaulis has a mild in vivo and in vitro anti-trypanosomal activity and can be considered as a potential source of new drugs for the treatment of Camel trypanosomiasis.