Planta Med 2016; 82(S 01): S1-S381
DOI: 10.1055/s-0036-1596329
Abstracts
Georg Thieme Verlag KG Stuttgart · New York

In vitro antimalarial interaction and transmission-blocking activity of cryptolepine

A Donkor Forkuo
1   Department of Pharmacology, Faculty of Pharmacy and Pharmaceutical Sciences, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
,
C Ansah
1   Department of Pharmacology, Faculty of Pharmacy and Pharmaceutical Sciences, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
,
B Gyan
2   Department of Immunology, Noguchi Memorial Institute for Biomedical Research, University of Ghana, Legon, Ghana
,
D Mancama
3   Biosciences, Council for Scientific and Industrial Research, Pretoria, South Africa
,
A Theron
3   Biosciences, Council for Scientific and Industrial Research, Pretoria, South Africa
› Author Affiliations
Further Information

Publication History

Publication Date:
14 December 2016 (online)

 

Cryptolepine is the main alkaloid in the root of the popular West African plant Cryptolepis sanguinolenta, frequently used as an antimalarial, antidysentery and febrifuge remedy [1]. The high patronage of the aqueous root extract of the popular West African antimalarial plant Cryptolepis sanguinolenta (Lindl.) Schlechter (Periplocaceae) in traditional and hospital settings in Ghana has directed this studies investigating the gametocytocidal potential as well as the antimalarial interaction of its major alkaloid, cryptolepine with standard antimalarial agents as the search for new antimalarial combinations continue. A fixed ratio method based on the SYBR Green I fluorescent-based assay [2] was used to build isobolograms from a combination of cryptolepine with four standard antimalarial drugs in vitro using the chloroquine sensitive strain 3D7. The ProtoBlue® assay [3] was employed in evaluating the transmission-blocking properties of Cryptolepis sanguinolenta and cryptolepine against the late stage gametocytes of Plasmodium falciparum (NF54). In the interaction assays, cryptolepine showed an additive effect with both lumefantrine and chloroquine with mean ΣFIC50s of 1.017 ± 0.45 and 1.342 ± 0.34, respectively. Cryptolepine combination with amodiaquine at therapeutically relevant concentration ratios showed a synergistic effect (mean ΣFIC50= 0.235 ± 0.15) whereas an antagonistic activity (mean ΣFIC50= 4.182 ± 0.68) was seen with mefloquine. Cryptolepis sanguinolenta and its major alkaloid showed minimal inhibitory activity against the late stage gametocytes of P. falciparum (NF54). The findings of this study shed light on the low transmission- blocking properties of Cryptolepis sanguinolenta and cryptolepine attributing their antimalarial activity mainly to their effect on the asexual stages of the parasite. Amodiaquine is a potential drug partner for cryptolepine in the development of novel fixed dose combinations.

Keywords: Cryptolepine, Cryptolepis sanguinolenta, malaria, transmission-blocking activity, antimalarial interaction, Plasmodium falciparum.

References:

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