Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
In French Guiana, Quassia amara L. (Simaroubaceae) leaf tea is a well-known widely used traditional antimalarial remedy. Impact of the vegetal sampling condition on in vivo and in vitro antimalarial activity was assessed. Traditional infusions were prepared with juvenile or mature leaves, both either fresh or dried. Results showed that growing stage and freshness of vegetal material exert a striking effect on antimalarial activity, both in vitro and in vivo. By far, leaf tea made from fresh juvenile (FJ) Quassia amara leaves was the most active. In vitro, active component (simalikalactone D) concentration correlates biological activities, although unexplained subtle variations were observed. In vivo, tea made with dried juvenile (DJ) leaves displays a peculiar behavior, meaning that some components may help simalikalactone D delivery or may be active in vivo only, therefore enhancing the expected curative effect of the traditional preparation.
ISSN: 0378-8741

hal-00384338
https://hal.archives-ouvertes.fr/hal-00384338
DOI : 10.1016/j.jep.2006.10.028

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Ethnopharmacological relevancePsidium acutangulum Mart. ex DC is a small tree used by the Wayana Amerindians from the Upper-Maroni in French Guiana for the treatment of malaria.Aim of the studyIn a previous study, we highlighted the in vitro antiplasmodial, antioxidant and anti-inflammatory potential of the traditional decoction of P. acutangulum aerial parts. Our goal was then to investigate on the origin of the biological activity of the traditional remedy, and eventually characterize active constituents.Materials and methodsLiquid-liquid extractions were performed on the decoction, and the antiplasmodial activity evaluated against chloroquine-resistant FcB1 ([3H]-hypoxanthine bioassay) and 7G8 (pLDH bioassay) P. falciparum strains, and on a chloroquine sensitive NF54 ([3H]-hypoxanthine bioassay) P. falciparum strain. The ethyl acetate fraction (D) was active and underwent bioguided fractionation. All the isolated compounds were tested on P. falciparum FcB1 strain. In vitro anti-inflammatory activity (IL-1β, IL-6, IL-8, TNFα) of the ethyl acetate fraction and of an anti-Plasmodium active compound, was concurrently assessed on LPS-stimulated human PBMC and NO secretion inhibition was measured on LPS stimulated RAW murine macrophages. Cytotoxicity of the fractions and pure compounds was measured on VERO cells, L6 mammalian cells, PBMCs, and RAW cells.ResultsFractionation of the ethyl acetate soluble fraction (IC50 ranging from 3.4 to <1 µg/mL depending on the parasite strain) led to the isolation of six pure compounds: catechin and five glycosylated quercetin derivatives. These compounds have never been isolated from this plant species. Two of these compounds (wayanin and guaijaverin) were found to be moderately active against P. falciparum FcB1 in vitro (IC50 5.5 and 6.9 µM respectively). We proposed the name wayanin during public meetings organized in June 2015 in the Upper-Maroni villages, in homage to the medicinal knowledge of the Wayana population. At 50 µg/mL, the ethyl acetate fraction (D) significantly inhibited IL-1β secretion (−46%) and NO production (−21%), as previously observed for the decoction. The effects of D and guiajaverin (4) on the secretion of other cytokines or NO production were not significant.ConclusionsThe confirmed antiplasmodial activity of the ethyl acetate soluble fraction of the decoction and of the isolated compounds support the previous results obtained on the P. acutangulum decoction. The antiplasmodial activity might be due to a mixture of moderately active non-toxic flavonoids. The anti-inflammatory activities were less marked for ethyl acetate fraction (D) than for the decoction.
ISSN: 0378-8741

hal-01313006
http://hal.upmc.fr/hal-01313006
http://hal.upmc.fr/hal-01313006/document
http://hal.upmc.fr/hal-01313006/file/Houel_Wayanin_and.pdf
DOI : 10.1016/j.jep.2016.04.053

Éditeur(s) : HAL CCSD American Society for Microbiology
Résumé :  
We report the isolation and identification of a new quassinoid named simalikalactone E (SkE), extracted from a widely used Amazonian antimalarial remedy made out of Quassia amara L. (Simaroubaceae) leaves. This new molecule inhibited the growth of Plasmodium falciparum cultured in vitro by 50%, in the concentration range from 24 to 68 nM, independently of the strain sensitivity to chloroquine. We also showed that this compound was able to decrease gametocytemia with a 50% inhibitory concentration sevenfold lower than that of primaquine. SkE was found to be less toxic than simalikalactone D (SkD), another antimalarial quassinoid from Q. amara, and its cytotoxicity on mammalian cells was dependent on the cell line, displaying a good selectivity index when tested on nontumorogenic cells. In vivo, SkE inhibited murine malaria growth of Plasmodium vinckei petteri by 50% at 1 and 0.5 mg/kg of body weight/day, by the oral or intraperitoneal routes, respectively. The contribution of quassinoids as a source of antimalarial molecules needs therefore to be reconsidered.
ISSN: 0066-4804

hal-01032126
https://hal.archives-ouvertes.fr/hal-01032126
DOI : 10.1128/AAC.00951-09

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
French Guiana (North-East Amazonia) records high malaria incidence rates. The traditional antimalarial remedy most widespread there is a simple tea made out from Quassia amara L. leaves (Simaroubaceae). This herbal tea displays an excellent antimalarial activity both in vitro and in vivo. A known quassinoid, simalikalactone D (SkD), was identified as the active compound, with an IC50 value of 10nM against FcB1 Plasmodium falciparum chloroquine resistant strain in vitro. Lastly, it inhibits 50% of Plasmodium yoelii yoelii rodent malaria parasite at 3.7 mg/kg/day in vivo by oral route. These findings confirm the traditional use of this herbal tea.
ISSN: 0378-8741

hal-00384337
https://hal.archives-ouvertes.fr/hal-00384337
DOI : 10.1016/j.jep.2006.04.017

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ISSN: 0378-8741

hal-01087030
https://hal-agroparistech.archives-ouvertes.fr/hal-01087030
DOI : 10.1016/j.jep.2009.07.037

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ETHNOPHARMACOLOGICAL RELEVANCE: Cutaneous leishmaniasis is a neglected disease with a high incidence in French Guiana, mainly in the middle and upper Oyapock basin, where Amerindian and some Brazilian people live. The main goals of this work were (i) to assess the knowledge about leishmaniasis in the different populations of the middle and upper Oyapock basin, (ii) to study the therapeutic strategies adopted by people affected by leishmaniasis and (iii) to document the use of phytotherapeutic remedies for leishmaniasis. Knowledge, attitudes and practices (K.A.P.) related to this disease and its treatments have been studied according to cultural group and geographical settlement. Within the Wayãpi group, the evolution of the knowledge of phytoremedies over the last 20 years has been characterised by literature-based comparisons. MATERIALS AND METHODS: A total of 144 questionnaires were administered in all the villages of the upper Oyapock and Camopi basins. Correspondence analyses were used for multivariate analysis. Plant species were identified at the Cayenne Herbarium (CAY). RESULTS: The biomedical concept of leishmaniasis correlates well with the Teko and Wayãpi concepts of kalasapa and kalasapau. Although the vector of this disease was not correctly identified, the most commonly cited aetiology (74.5%) was vector-borne, and related epidemiological schemes correlate well with the one encountered in French Guiana. Theoretically and practically, health centres were the most commonly used resource for diagnostic in instances of leishmaniasis infection (65.9%), independently of the patient's cultural group, along with the use of pharmaceutical drugs (85.3%). Pharmaceuticals were commonly utilised despite the frequent (51.5%) use of phytotherapeutic remedies, alone or in combination with drugs. The most cited medicinal plant species for the treatment of leishmaniasis included Eleutherine bulbosa (Mill.) Urb. (Iridaceae, cited 14 times), Euterpe oleracea Mart. (Arecaceae, 9), Cecropia obtusa Trecul (Cecropiaceae, 8), Jatropha curcas L. (Euphorbiaceae, 7), Ceiba pentandra (L.) Gaertn. (Bombacaceae, 6) and Carica papaya L. (Caricaceae, 6). Multiple correspondence analyses demonstrated that the species used in leishmaniasis remedies are more prone to vary by the user's place of residence than by their cultural origin, which indicates that exchange of knowledge about leishmaniasis remedies has occurred across different cultural groups. Literature-based comparisons between the remedies for leishmaniasis used by the Wayãpi during the 1980s showed a striking evolution, both in terms of diversity of species and number of plants used. The large number of species shared with other Guianese groups argues for intercultural exchange and may explain the majority (57.1%) of the newly used species highlighted in our study. CONCLUSIONS: Leishmaniasis is a well-known disease in the studied area. Phytotherapeutic treatments are still in use, although they are not the main source of remedies, and should undergo pharmacological studies to evaluate their potential therapeutic value.
ISSN: 0378-8741

pasteur-00634597
https://hal-riip.archives-ouvertes.fr/pasteur-00634597
DOI : 10.1016/j.jep.2011.07.044
PUBMED : 21816216

Éditeur(s) : HAL CCSD Elsevier
Résumé : Ethnopharmacological relevance: Cutaneous and mucocutaneous leishmaniasis are neglected tropical diseases that occur in all intertropical regions of the world. Amazonian populations have developed an abundant knowledge of the disease and its remedies. Therefore, we undertook to review traditional antileishmanial plants in Amazonia and have developed new tools to analyze this somewhat dispersed information.Material and methods: A literature review of traditional remedies for cutaneous/mucocutaneous leishmaniasis in the Amazon was conducted and the data obtained was used to calculate distribution indexes designed to highlight the most relevant uses in Amazonia. The cultural distribution index represents the distribution rate of a given taxon among different cultural groups and was calculated as the ratio of the number of groups using the taxon to the total number of groups cited. The geographical distribution index allowed us to quantify spatial distribution of a taxon's uses in Amazonia and was calculated geometrically by measuring the average distance between the points where uses have been reported and the barycenter of those points. The general distribution index was defined as an arithmetic combination of the previous two and provides information on both cultural and spatial criteria.Results: 475 use reports, concerning 291 botanical species belonging to 83 families have been gathered depicted from 29 sources. Uses concern 34 cultural groups. While the use of some taxa appears to be Pan Amazonian, some others are clearly restricted to small geographical regions. Particular attention has been paid to the recipes and beliefs surrounding treatments. Topical application of the remedies dominated the other means of administration and this deserves particular attention as the main treatments against Neotropical leishmaniasis are painful systemic injections. The data set was analyzed using the previously defined distribution indexes and the most relevant taxa were further discussed from a phytochemical and pharmacological point of view.Conclusions: The Amazonian biodiversity and cultural heritage host a fantastic amount of data whose systematic investigation should allow a better large-scale understanding of the dynamics of traditional therapies and the consequent discovery of therapeutic solutions for neglected diseases. Distribution indices are indeed powerful tools for emphasizing the most relevant treatments against a given disease and should be very useful in the meta-analysis of other regional pharmacopeia. This focus on renowned remedies that have not yet benefitted from extended laboratory studies, could stimulate future research on new treatments of natural origin for leishmaniasis.
ISSN: 0378-8741

hal-01603285
https://hal.archives-ouvertes.fr/hal-01603285
DOI : 10.1016/j.jep.2017.01.048
PRODINRA : 401890

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ISSN: 0378-8741

hal-01152706
https://hal.archives-ouvertes.fr/hal-01152706
DOI : 10.1016/j.jep.2015.03.015

Éditeur(s) : HAL CCSD
Résumé : After a review of knowledge, attitudes and practices related to leishmaniasis in Amazonia, this work focused on the vegetal species used for its cure. Utilization of geographic and cultural diffusion index allowed to characterize Pan-Amazonian antileishmanial taxa and to investigate the mechanisms allowing for their diffusion. Consistency between traditional use and laboratory results were looked for. Two " knowledge, attitudes and practices " surveys were conducted amongst the Chayahuita (Peru) and along the upper and middle Oyapock river (French Guiana, Teko and Wayãpi groups). These allowed us to refine the knowledge and perception of the disease in these cultural groups, to define patterns in the therapeutic itinerary, and to make an inventory of antileishmanial plant species. Thirty one species used by the Chayahuita were collected and submitted to in vitro assays on axenic amastigotes of Leishmania amazonensis. Pseudoelephantopus spicatus (Asteraceae) is one of the most active and most frequently used plant. From this species, piptocarphol derivatives, very active against Leishmania in vitro, were isolated along with ursolic acid. Presence of these molecules justifies the use of this species as traditional antileishmanial remedy by the Chayahuita.
Après avoir dressé un inventaire des connaissances, attitudes et pratiques concernant les leishmanioses en Amazonie d'après la littérature, le présent travail s'est focalisé sur les espèces végétales connues et utilisées dans le traitement de ces maladies. L'utilisation d'indices de diffusion (géographique, culturelle) a permis de caractériser des taxons antileishmaniens panamazoniens et de définir certains mécanismes impliqués dans leur diffusion. Des cohérences entre usages traditionnels et résultats de laboratoire ont été recherchés. Deux enquêtes de type " connaissance, attitudes et pratiques " effectuées au sein du groupe chayahuita (Pérou), et sur le haut et moyen cours du fleuve Oyapock (Guyane, communautés teko et wayãpi) ont permis d'affiner les connaissances sur la perception de cette maladie dans ces différents groupes culturels, de comprendre les recours aux différentes thérapeutiques et de dresser un inventaire des espèces médicinales utilisées. Trente et une espèces collectées chez les Chayahuita ont été soumises à des essais in vitro sur amastigotes axéniques de Leishmania amazonensis. Pseudoelephantopus spicatus (Asteraceae) compte parmi les espèces les plus actives et les plus fréquemment utilisées, et des dérivés du piptocarphol très actifs sur les parasites in vitro ont été isolés conjointement à l'acide ursolique. La présence de ces molécules permet de justifier en partie l'usage de cette espèce comme antileishmanien traditionnel par les Chayahuita.
https://tel.archives-ouvertes.fr/tel-00590977

tel-00590977
https://tel.archives-ouvertes.fr/tel-00590977
https://tel.archives-ouvertes.fr/tel-00590977/document
https://tel.archives-ouvertes.fr/tel-00590977/file/ThA_se_Odonne_light.pdf