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Agyare C.,Kwame Nkrumah University Of Science And Technology | Spiegler V.,University of Munster | Sarkodie H.,Kwame Nkrumah University Of Science And Technology | Asase A.,University of Ghana | And 2 more authors.
Journal of Ethnopharmacology | Year: 2014

Ethnopharmacological relevance Infections with helminths are still a big problem in many parts of the world. The majority of the people in West Africa treat such infections with medicinal plants related to the local traditional medicine. The present study aims at identifying medicinal plants traditionally used for worm infections in the Ashanti region, Ghana. In vitro screening of selected extracts from plants on which scientific knowledge is limited was to be performed.Materials and methods Validated questionnaires were administered to 50 traditional healers in the Ashanti region, Ghana. Interviews and structured conversations were used to obtain relevant information. Quantitative and qualitative evaluation was performed additionally to structured cross-referencing of the data using SciFinder® data base. Selected plant species were used for in vitro testing on anthelmintic activity against the free-living model nematode Caenorhabditis elegans.Results 35 plant species were recorded for the use in humans and 6 for the use in animals. Plant material most frequently used were the seeds from Carica papaya, mentioned by nearly all healers. The plausibility of most plants used for treatment of infections with helminths was given in most cases by documentation of potential anthelmintic activity in recent scientific literature. 9 species from plants not or scarcely described in literature for this indication were investigated on in vitro activity. A hydroethanolic (1:1) extract of Combretum mucronatum was most active with a survival rate of nematodes of 89% at 0.1 mg/mL and 58% at 1 mg/mL respectively (levamisole 16%). Extracts of Paullinia pinnata and Phyllanthus urinaria were also assessed to exhibit a minor (85% and 89% respectively at 1 mg/mL), but still significant activity.Conclusion Traditional use of anthelmintic plants from Ghana can be well rationalized by cross-referencing with published literature and phytochemical/pharmacological plausibility.The in vitro investigations of extracts from Combretum mucronatum, Paullinia pinnata and Phyllanthus urinaria exhibited significant effects against nematodes. The anthelmintic activity of these plants should be investigated in detail for pinpointing the respective lead structures responsible for the activity. © 2014 Elsevier Ireland Ltd. All rights reserved.

Spiegler V.,University of Munster | Liebau E.,Institute for Zoophysiology | Peppler C.,University of Munster | Raue K.,University of Veterinary Medicine Hannover | And 7 more authors.
Planta Medica | Year: 2016

Paullinia pinnata is a medicinal plant traditionally used in West Africa against a wide range of diseases including soil-transmitted helminthiases. In this study, a hydroethanolic root extract was investigated for its phytochemical composition and in vitro activity against the free-living nematode Caenorhabditis elegans as well as the larval stages of the parasitic helminths Ancylostoma caninum, Haemonchus contortus, Toxocara cati, and Trichuris vulpis. LC-MS analysis of the ethanol-water (1?:?1) extract revealed epicatechin and different A-type linked oligomeric and polymeric procyanidins as the predominant compounds. Within an in vitro mortality assay, the extract showed a lethal activity against T. cati (LC50 of 112 µg/mL), T. vulpis (LC50 of 17 µg/mL), and C. elegans (LC50 2.5 of mg/mL), but not against A. caninum. Additionally, effects on egg hatching and larval migration of H. contortus were investigated, but no inhibitory activity was observed. Overall, these findings rationalize the traditional use of the root extract from P. pinnata as an anthelmintic remedy and provide insight into the phytochemical composition of the extract. Copyright © 2016, Georg Thieme Verlag KG. All rights reserved.

Ndjonka D.,University of Ngaoundere | Rapado L.N.,University of Sao Paulo | Silber A.M.,University of Sao Paulo | Liebau E.,Institute for Zoophysiology | Wrenger C.,University of Sao Paulo
International Journal of Molecular Sciences | Year: 2013

Infectious diseases caused by parasites are a major threat for the entire mankind, especially in the tropics. More than 1 billion people world-wide are directly exposed to tropical parasites such as the causative agents of trypanosomiasis, leishmaniasis, schistosomiasis, lymphatic filariasis and onchocerciasis, which represent a major health problem, particularly in impecunious areas. Unlike most antibiotics, there is no "general" antiparasitic drug available. Here, the selection of antiparasitic drugs varies between different organisms. Some of the currently available drugs are chemically de novo synthesized, however, the majority of drugs are derived from natural sources such as plants which have subsequently been chemically modified to warrant higher potency against these human pathogens. In this review article we will provide an overview of the current status of plant derived pharmaceuticals and their chemical modifications to target parasite-specific peculiarities in order to interfere with their proliferation in the human host. © 2013 by the authors; licensee MDPI, Basel, Switzerland.

Ndjonka D.,University of Ngaoundere | Abladam E.D.,University of Ngaoundere | Djafsia B.,University of Ngaoundere | Ajonina-Ekoti I.,Institute for Zoophysiology | And 2 more authors.
Journal of Helminthology | Year: 2014

The effect of three phenols (ellagic, gentisic and gallic acids) from the axlewood tree Anogeissus leiocarpus on Onchocerca ochengi and drug-resistant strains of Caenorhabditis elegans, a model organism for research on nematode parasites, is investigated. Worms were incubated in different concentrations of phenols and their survival was monitored after 48 h. Among the three acids, ellagic acid strongly affected the survival of O. ochengi microfilariae, O. ochengi adults, a wild-type C. elegans and anthelmintic-resistant strains of C. elegans, namely albendazole (CB3474), levamisole (CB211, ZZ16) and ivermectin (VC722, DA1316), with LC50 values ranging from 0.03 mm to 0.96 mm. These results indicate that the binding of ellagic acid in the worm differs from that of resistant strains of C. elegans. The efficacy of both gallic and gentisic acids was not significantly changed in resistant strains of C. elegans treated with levamisole (ZZ16, LC50= 9.98 mm, with gallic acid), albendazole (CB3474, LC50= 7.81 mm, with gentisic acid) and ivermectin (DA1316, LC50= 10.62 mm, with gentisic acid). The efficacy of these three pure compounds is in accordance with the use of A. leiocarpus from its locality of origin. The in vivo toxicity data reveal that the thresholds are up to 200 times higher than the determined LC50 values. Thus, ellagic acid could be a potential option for the treatment of nematode infections, even in cases of drug resistance towards established anthelmintic drugs. © Cambridge University Press 2013.

Djafsia B.,University of Ngaoundere | Djafsia B.,Bernhard Nocht Institute for Tropical Medicine | Ndjonka D.,University of Ngaoundere | Dikti J.V.,University of Ngaoundere | And 5 more authors.
Journal of Helminthology | Year: 2015

Excretory–secretory (ES) products of nematodes and other helminths are the first molecules to interact with cell surfaces and soluble proteins within the host. In the present study, ES products of the filarial nematode Onchocerca ochengi were investigated as a model for Onchocerca volvulus, the causative agent of river blindness. These products were collected from adult and larval stages in vitro over a period of 7 days, to compare their immunological recognition in cattle and human sera, infected with species of Onchocerca. From the 156 sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) ES products or extracts, protein bands showed different patterns between female and male products. A comparison of antibody recognition of the different ES products by sera from infected cattle and humans, when analysed by enzyme-linked immunosorbent assay (ELISA), revealed a relatively higher reactivity of the female somatic extract to human and cattle sera compared to ES products of both genders. Nevertheless, similar reactivity of the O. ochengi male and female ES products to human and cattle sera was noticed. As a result, the interaction of ES products with the surface of the host and immune system often led to host responses, including the generation of antibodies. The O. ochengi ES products are therefore good sources of potential immunogenic proteins. The identification of these ES products is in progress, with the aim of developing vaccine candidates against human onchocerciasis. Copyright © Cambridge University Press 2015

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