Geneviève Bourdy

Maternity and medicinal plants in Vanuatu. I: The cycle of reproduction

Ethnobotanical data collection to select pharmacologically active species was carried out within a clearly defined therapeutic context: those plants used during the course of a womans reproductive life. Extensive bibliographical and field data collection and cross-examination of the information thus gathered have provided us with a clearer picture of the effectiveness of these plant species. Various concepts, behaviours and practices relating to menstruation, pregnancy, birth and birth control were examined in detail from an ethnopharmacological point of view. A list of selected species of particular interest is proposed for further study.

Antimalarial Activity of Simalikalactone E, a New Quassinoid from Quassia amara L. (Simaroubaceae)

ABSTRACT 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.

Traditional remedies used in the Western Pacific for the treatment of ciguatera poisoning

Ciguatera is a specific type of food poisoning associated with the ingestion of tropical fish, which, although normally safe for consumption, may at times contain high amounts of ciguatoxin, as well as other chemically related toxins. Widespread in tropical regions where coral reefs are present, ciguatera fish poisoning constitutes a major hindrance for local fishing industries, local economies and foreign trade. Because no symptomatic treatment has been totally satisfactory, folk remedies remain of great interest. In this paper, a list of plants used in treating ciguatera poisoning in the Western Pacific region is presented, with emphasis on species whose exact utilization (part of plant used, preparation, dosage) has been determined.

Anti-inflammatory activity of Mitraphylline isolated from Uncaria tomentosa bark.

ETHNOPHARMACOLOGICAL RELEVANCEnUncaria tomentosa (Willd. ex Roem. & Schult.) DC. (Rubiaceae) is widely used by populations living in South America to treat many ailments associated with inflammatory disorders. Mitraphylline was shown to be the major pentacyclic oxindolic alkaloid present in the bark chloroformic extract of this plant. Its activity against cytokines involved in inflammation process was tested in a murine model in vivo.nnnMATERIALS AND METHODSnMice received mitraphylline once a day for 3 days at 30 mg/kg/day by oral route. Then, they were subjected to bacterial lipopolysaccharide (LPS) endotoxin (15 mg/kg) and the LPS-induced production of 16 different cytokines was determined by Elisa multiplex. Control group received dexamethasone orally at 2mg/kg/day. Toxicity on K565 cells and murine peritoneal macrophages, in vitro, at doses up to 100 μM was monitored by XTT-colorimetric assay.nnnRESULTS AND CONCLUSIONSnFor the first time mitraphylline was tested in vivo against a large range of cytokines that play a crucial role in inflammation. Mitraphylline inhibited around 50% of the release of interleukins 1α, 1β, 17, and TNF-α. This activity was similar to dexamethasone. It also reduced almost 40% of the production of interleukin 4 (IL-4) while the corticoid did not. Lastly it did not show any toxicity on K565 cells nor murine macrophages at doses up to 100 μM.

Medical ethnobotany of the Chayahuita of the Paranapura basin (Peruvian Amazon)

ETHNOPHARMACOLOGICAL RELEVANCEnUp until now, the plant pharmacopoeia of the Chayahuita, an ethnic group from the Peruvian Amazon, has been poorly defined. This paper details the uses of medicinal plants within this community, as recorded in two villages of the Paranapura basin, Soledad and Atahualpa de Conchiyacu. This study aimed to describe the basis of the Chayahuita traditional medical system, to document part of the medicinal plant corpus, and to compare it with data from other Amazonian ethnic groups.nnnMATERIAL AND METHODSnMethodology was based (i) on field prospection with 26 informants (ethnobotanical walks methodology), (ii) semi-structured interviews including 93 people (49 men and 44 women) focused on the most recent health problem experienced and on the therapeutic options chosen, (iii) individual or group thematic discussions relating to disease and treatments, (iv) 6-months of participants observations between May 2007 and May 2008. At the end of the project in May 2008 a workshop was organized to cross-check the data with the help of 12 of the most interested informants.nnnRESULTSnSix hundred and seventeen voucher specimens were collected, corresponding to 303 different species, from which 274 (belonging to 83 families) are documented here. Altogether 492 recipes were recorded, corresponding to a global figure of 541 therapeutic uses and a total of 664 use reports. The main therapeutic uses are related to dermatological problems (103 uses; 19%), gastro-intestinal complaints (69 uses; 13%) and malaria/fevers (52 uses; 10%). Diseases are analysed according to Chayahuita concepts, and for each disease the species having a high frequency of citation are listed, and the most frequently used remedies are described. Whenever possible, comparisons with other Amazonian groups have been drawn.nnnCONCLUSIONnChayahuita nosology and medical ethnobotany appear to draw their inspiration from a common panamazonian root. Despite the fact that a certain number of medicinal plants are shared with other nearby groups, there seem to be specific uses for some species, thus highlighting the originality of the Chayahuita pharmacopoeia. Presently there is a certain disinterest in the most traditional area of the Chayahuita medical ways, and the role of the penutu (shaman) seems to be less highly-valued than in the past. Nonetheless, the use of medicinal plants in phytotherapeutic treatment is very much a living, shared knowledge.

Four anti-protozoal and anti-bacterial compounds from Tapirira guianensis

Tapirira guianensis is a common tree used in traditional medicine in French Guiana against several infectious diseases (malaria, leishmaniasis, bacteria, etc.). The bioassay-guided purification of CH(2)Cl(2) bark extract led to the isolation of four cyclic alkyl polyol derivatives: 4,6,2-trihydroxy-6-[10(Z)-heptadecenyl]-1-cyclohexen-2-one (1a), 1,4,6-trihydroxy-1,2-epoxy-6-[10(Z)-heptadecenyl]-2-cyclohexene (1b), 1,4,5,2-tetrahydroxy-1-[10(Z)-heptadecenyl]-2-cyclohexene (2), and 1,3,4,6-tetrahydroxy-1,2-epoxy-6-[10(Z)-heptadecenyl]-cyclohexane (3). The structures were established on the basis of 1D and 2D NMR analyses. The anti-leishmanial, anti-plasmodial, anti-bacterial (on Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli), and anti-fungal (on Candida albicans) activities of the extracts and of these original compounds were evaluated. Two showed medicinal interest supporting the traditional uses of the plant. The structures were established through spectral analyses of the isolates and their derivatives.

Saponins from Pisonia umbellifera.

Six saponins were isolated from the leaves of Pisonia umbellifera. Three are new oleanolic acid saponins, and two of them contain an unusual seco-glycopyranosyl moiety. Their structures were determined using a combination of 1H and 13C NMR, and mass spectrometry as 3-O-{beta-D-glucopyranosyl(1-->2)[beta-D-glucopyranosyl (1-->2)-beta-D-xylopyranosyl(1-->3)]-beta-D-glucuronopyranosyl} 28-O-beta-D-glucopyranosyl olean-12-en-3 beta-ol-28-oic acid, 3-O-{2-(2-O-glycolyl)-glyoxylyl-beta-D-glucuronopyranos yl} 28-O-beta-D-glucopyranosyl olean-12-en-3 beta-ol-28-oic acid and 3-O-{2-O-glycolyl)-glyoxylyl-beta-D-glucuronopyranosyl++ +} olean-12-en-3 beta-ol-28-oic acid.

Antiplasmodial activity of New Caledonia and Vanuatu traditional medicines

Context: With the emergence of strains multiresistant to antimalarial drugs, the search for new active molecules remains a priority. Ethnopharmacology appears to be a good method of selection in such investigations. Objective: The aim of this research work is to select plants used in Melanesian traditional medicine, in New Caledonia and Vanuatu, which should be a promising source for the isolation of new antimalarial drugs. Materials and methods: Forty-seven plant extracts belonging to 12 families, traditionally used by the Melanesian people or belonging to an antimalarial known genus, were screened in vitro for antimalarial activity on Plasmodium falciparum chloroquine (CQ)-resistant (FcB1) and CQ-sensitive (HB3) strains. They were also tested for their inhibitory effects on a protein kinase (Pfnek) and their cytotoxicity on human breast adenocarcinoma (MCF7) cells. Results: Among all extracts, four displayed strong in vitro activities against P. falciparum: Gardenia urvillei Montrouzier, Scleria polycarpa Boeckeler, Terminalia catappa L. and Acronychia laevis J.R. & J.G. Forster, the latter being also toxic on MCF7 cells. Except for the extracts of S. polycarpa, all others that were active on P. falciparum, also possess an inhibitory effect on Pfnek. Discussion and conclusion: These results confirm that ethnopharmacology is an excellent approach for such investigations. The two countries considered clearly present advantages in the field. Indeed, local populations keep their traditional knowledge alive, and their flora is exceptionally rich. In New Caledonia, the high endemicity rate (74%) ranks the island as one of the world’s biodiversity hotspots. As a consequence, chances to discover new active natural compounds are also high.

A 13-Year Retrospective Study on Primary Liver Cancer in Cambodia: A Strikingly High Hepatitis C Occurrence among Hepatocellular Carcinoma Cases

Objectives: Hepatocellular carcinoma (HCC) is the main type of primary liver cancer (PLC) worldwide, but cholangiocarcinoma (CCA) may be predominant in some specific regions of Southeast Asia. The aim of the present study was to delineate a pattern of Cambodian PLC patients attending the Calmette Hospital in the Cambodian capital Phnom Penh. Materials and Methods: A total of 553 medical charts diagnosing PLCs from January 2003 to May 2015 were obtained from both the Oncology and Hepato-Gastroenterology Departments of the Calmette Hospital. Results: HCC was the predominant type of PLC recorded, with 511 cases (92.4%), whereas CCA represented merely 7.6% (42 cases) of the overall series. Hepatitis B virus (HBV; 44.3%) and hepatitis C virus (HCV; 43%) infection rates were similar among the HCC patients, while small subsets of CCA patients were infected with HBV (15.4%) or HCV (11.5%). Most HCC (84%) and CCA (73.8%) patients received palliative treatment only. Conclusion: The present study indicates that HCC is the main form of primary hepatic neoplasm among PLC patients attending a hospital in Cambodia. HBV and HCV infections represented equivalent burdens and major contributing factors to HCC. Therefore, the implementation of prevention programs for these infectious agents should become a priority for health policy makers in the country.

New findings on Simalikalactone D, an antimalarial compound from Quassia amara L. (Simaroubaceae)

Quassia amara L. (Simaroubaceae) is a species widely used as tonic and is claimed to be an efficient antimalarial all over the Northern part of the Amazon basin. Quassinoid compound Simalikalactone D (SkD) has been shown to be one of the molecules responsible for the antiplasmodial activity of a watery preparation made out of juvenile fresh leaves of this plant. Because of its strong antimalarial activity, we decided to have a further insight of SkD pharmacological properties, alone or in association with classical antimalarials. At concentrations of up to 200μM, we showed herein that SkD did not exert any apoptotic or necrotic activities in vitro on lymphoblastic cells. However, an antiproliferative effect was evident at concentrations higher than 45nM. SkD was inefficient at inhibiting heme biomineralization and the new permeability pathways induced by the parasite in the host erythrocyte membrane. With respect to Plasmodium falciparum erythrocytic stages, SkD was almost inactive on earlier and later parasite stages, but potently active at the 30th h of parasite cycle when DNA replicates in mature trophozoites. In vitro combination studies with conventional antimalarial drugs showed that SkD synergizes with atovaquone (ATO). The activity of ATO on the Plasmodium mitochondrial membrane potential was enhanced by SkD, which on its own had a poor effect on this cellular parameter.