In Vitroandin VivoChloroquine-Potentiating Action ofStrychnos myrtoidesAlkaloids Against Chloroquine-Resistant Strains ofPlasmodiumMalaria

Publisher Website
Google Scholar
Abstract
Crude alkaloids of Strychnos myrtoides Gilg & Busse, empirically used as an adjuvant to chloroquine (CQ) in Malagasy herbal remedies, were practically devoid of intrinsic in vitro and in vivo anti-malarial activity. However, when combined with CQ at a dose level much lower than their IC50 value, they markedly enhanced in vitro the effectiveness of the synthetic drug against a CQ-resistant strain of Plasmodium falciparum. They also enhanced in vivo CQ activity against a resistant strain of Plasmodium yoelii. By counter-current distribution (CCD) separation of the crude alkaloid extract, the two major alkaloids strychnobrasiline (1) and malagashanine (2), together with four minor alkaloids, were isolated. Strychnobrasiline and malagashanine were devoid of both intrinsic anti-malarial activity and cytotoxicity effect, but exhibited significant CQ-potentiating actions. These findings could account for the above-mentioned empirical use of S. myrtoides. The present state of research on anti-malarial drug from Strychnos genus is also discussed.

This publication has 0 references indexed in Scilit: