Filaricidal activity of Daniellia oliveri and Psorospermum febrifugum extracts

Parasites & Vectors

Fidelis Cho-Ngwa¹  Moses Samje²  Judy Sakanari³  Christina Bulman³  Nick J. Koszewski⁴  Richard J. Martin⁴  Melanie Abongwa⁴  Jesse Goff⁴  Saurabh Verma⁴  Alan P. Robertson⁴  Godfred A. Ayimele⁵  Smith B. Babiaka⁵ 

[1]ANDI Centre of Excellence for Onchocerciasis Drug Research, Faculty of Science, University of Buea, South West Region, Buea, Cameroon

[2]ANDI Centre of Excellence for Onchocerciasis Drug Research, Faculty of Science, University of Buea, South West Region, Buea, Cameroon

[3]Department of Biomedical Sciences, Faculty of Health Sciences, University of Bamenda, Bamenda, Cameroon

[4]Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, CA, USA

[5]Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, USA

[6]Department of Chemistry, Faculty of Science, University of Buea, South West Region, Buea, Cameroon

关键词: Onchocerciasis;    Lymphatic filariasis;    Daniellia oliveri;    Psorospermum febrifugum;    Cytotoxicity;   

DOI  :  10.1186/s13071-021-04759-6

来源: Springer

【 摘 要 】

BackgroundDrugs currently used for controlling onchocerciasis and lymphatic filariasis (LF) are mainly microfilaricidal, with minimal or no effect on the adult worms. For efficient management of these diseases, it is necessary to search for new drugs with macrofilaricidal activities that can be used singly or in combination with existing ones. Daniellia oliveri and Psorospermum febrifugum are two plants commonly used in the local management of these infections in Bambui, a township in the North West Region of Cameroon, but there is currently no documented scientific evidence to support their claimed anthelmintic efficacy and safety. The aim of this study was to provide evidence in support of the search for means to eliminate these diseases by screening extracts and chromatographic fractions isolated from these plants for efficacy against the parasitic roundworms Onchocerca ochengi and Brugia pahangi.MethodsThe viability of O. ochengi adult worms was assessed using the MTT/formazan assay. Fully confluent monkey kidney epithelial cells (LLC-MK2) served as the feeder layer for the O. ochengi microfilariae (mfs) assays. Viability of the mfs was assessed by microscopic examination for mean motility scoring (relative to the negative control) every 24 h post addition of an extract. The Worminator system was used to test the effects of the extracts on adult B. pahangi motility, and mean motility units were determined for each worm. Cytotoxicity of the active extracts on N27 cells was assessed using the MTS assay.ResultsExtracts from D. oliveri and P. febrifugum were effective against the adult roundworms O. ochengi and B. pahangi. Interestingly, extracts showing macrofilaricidal activities against O. ochengi also showed activity against O. ochengi mfs. The hexane stem bark extract of D. oliveri (DOBHEX) was more selective for adult O. ochengi than for mfs, with a half maximal and 100% inhibitory concentration (IC50 and IC100, respectively) against adult O. ochengi of 13.9 and 31.3 μg/ml, respectively. The in vitro cytotoxicity of all active extracts on N27 cells showed selective toxicity for parasites (selectivity index > 1). Bioassay-guided fractionation of the extracts yielded fractions with activity against adult B. pahangi, thus confirming the presence of bioactive principles in the plant extracts.ConclusionsOur study supports the use of D. oliveri and P. febrifugum in the traditional treatment of onchocerciasis and LF. The further purification of active extracts from these plants could yield lead compounds for filarial drug discovery and development.Graphical Abstract

【 授权许可】

CC BY