Compounds derived from the Bhutanese daisy, Ajania nubigena, demonstrate dual anthelmintic activity against Schistosoma mansoni and Trichuris muris

Wangchuk, Phurpa, Pearson, Mark S., Giacomin, Paul R., Becker, Luke, Sotillo, Javier, Pickering, Darren, Smout, Michael J., and Loukas, Alex (2016) Compounds derived from the Bhutanese daisy, Ajania nubigena, demonstrate dual anthelmintic activity against Schistosoma mansoni and Trichuris muris. PLOS Neglected Tropical Diseases, 10 (8). e0004908. pp. 1-18.

[img]
Preview
PDF (Published Version) - Published Version
Available under License Creative Commons Attribution.

Download (6MB) | Preview
View at Publisher Website: http://dx.doi.org/10.1371/journal.pntd.0...
 
16
49


Abstract

Background: Whipworms and blood flukes combined infect almost one billion people in developing countries. Only a handful of anthelmintic drugs are currently available to treat these infections effectively; there is therefore an urgent need for new generations of anthelmintic compounds. Medicinal plants have presented as a viable source of new parasiticides. Ajania nubigena, the Bhutanese daisy, has been used in Bhutanese traditional medicine for treating various diseases and our previous studies revealed that small molecules from this plant have antimalarial properties. Encouraged by these findings, we screened four major compounds isolated from A. nubigena for their anthelmintic properties.

Methodology/Principal Findings: Here we studied four major compounds derived from A. nubigena for their anthelmintic properties against the nematode whipworm Trichuris muris and the platyhelminth blood fluke Schistosoma mansoni using the xWORM assay technique. Of four compounds tested, two compounds—luteolin (3) and (3R,6R)-linalool oxide acetate (1)—showed dual anthelmintic activity against S. mansoni (IC50 range = 5.8–36.9 μg/mL) and T. muris (IC50 range = 9.7–20.4 μg/mL). Using scanning electron microscopy, we determined luteolin as the most efficacious compound against both parasites and additionally was found effective against the schistosomula, the infective stage of S. mansoni (IC50 = 13.3 μg/mL). Luteolin induced tegumental damage to S. mansoni and affected the cuticle, bacillary bands and bacillary glands of T. muris. Our in vivo assessment of luteolin (3) against T. muris infection at a single oral dosing of 100 mg/kg, despite being significantly (27.6%) better than the untreated control group, was markedly weaker than mebendazole (93.1%) in reducing the worm burden in mice.

Conclusions/Significance: Among the four compounds tested, luteolin demonstrated the best broad-spectrum activity against two different helminths—T. muris and S. mansoni—and was effective against juvenile schistosomes, the stage that is refractory to the current gold standard drug, praziquantel. Medicinal chemistry optimisation including cytotoxicity analysis, analogue development and structure-activity relationship studies are warranted and could lead to the identification of more potent chemical entities for the control of parasitic helminths of humans and animals.

Item ID: 45187
Item Type: Article (Research - C1)
ISSN: 1935-2735
Additional Information:

© 2016 Wangchuk et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Funders: National Health and Medical Research Council of Australia (NHMRC)
Projects and Grants: NHMRC grant no. APP1037304, NHMRC grant no. APP1091011
Date Deposited: 16 Aug 2016 03:54
FoR Codes: 11 MEDICAL AND HEALTH SCIENCES > 1115 Pharmacology and Pharmaceutical Sciences > 111599 Pharmacology and Pharmaceutical Sciences not elsewhere classified @ 70%
11 MEDICAL AND HEALTH SCIENCES > 1103 Clinical Sciences > 110309 Infectious Diseases @ 30%
SEO Codes: 92 HEALTH > 9201 Clinical Health (Organs, Diseases and Abnormal Conditions) > 920109 Infectious Diseases @ 70%
92 HEALTH > 9202 Health and Support Services > 920299 Health and Support Services not elsewhere classified @ 30%
Downloads: Total: 49
Last 12 Months: 11
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page