Abstract:
Background: Conventional targeted leishmanicidal chemotherapy has persistently remained prohibitive for most
economically deprived communities due to costs, associated time to accessing health services and duration for suc‑
cessful treatment programme. Alternatives are bound to be incorporated in rational management of leishmaniasis
by choice or default due to accessibility and cultural beliefs. Therefore, there is need to rigorously investigate and
appraise the activity of medicinal compounds that may have anti-leishmanicidal activity especially in the context of
products that are already being utilized by the populations for other ailments but have limited information on their
therapeutic value and possible cytoxicity. Hence, the study examined both in vivo and in vitro response of L. major
infection to Tephrosia vogelii extracts in BALB/c mice as the mouse model.
Methods: A comparative study design was applied for the in vivo and in vitro assays of the extract with Pentostam
(GlaxoSmithKline, UK) and Amphotericin B [Fungizone™, X-Gen Pharmaceuticals (US)] as standard drugs.
Results: In BALB/c mice where the chemotherapeutic extract was administered intraperitoneally, there was sig‑
nifcantly (p < 0.05) larger reduction in lesion size and optimal control of parasite burden than those treated orally.
However, standard drugs showed better activity. Tephrosia vogelii had 50% inhibitory concentration (IC50) and IC90 of
12 and 68.5 μg/ml respectively, while the standard drugs had IC50 and IC90 of 5.5 and 18 μg/ml for Pentostam and 7.8
and 25.5 μg/ml for Amphotericin B in that order. In the amastigote assay, the infection rates decreased with increase
in chemotherapeutic concentration. The multiplication indices for L. major amastigotes in macrophages treated with
200 µg/ml of the standard drugs and extract were signifcantly diferent (p < 0.05). 200 µg/ml of T. vogelii extract
showed a multiplication index of 20.57, 5.65% for Amphotericin B and 9.56% for Pentostam. There was also signifcant
diference (p < 0.05) in levels of Nitric oxide produced in the macrophages.
Conclusions: The fndings demonstrated that T. vogelii extract has anti-leishmanial activity and further assays should
be done to ascertain the active compounds responsible for anti-leishmanial activity
