La mycothérapie au Burkina Faso : État des lieux et perspectives

Objectif : Les vertus médicinales des champignons supérieurs sont connues depuis des millénaires, notamment à travers la médecine asiatique. En Afrique de l’ouest, les recherches menées dans ce domaine sont rares. Cette étude est une contribution à la connaissance des champignons supérieurs utilisés dans la médecine traditionnelle au Burkina Faso. Méthodologie et résultats : L’étude a été réalisée dans la ville de Ouagadougou à partir d’enquêtes ethnomycologiques auprès de 60 tradipraticiens. Les résultats obtenus à l’issue de ces enquêtes ont permis d’identifier huit (8) espèces de champignons supérieurs utilisées en tradithérapie. Il s’agit de : Daldinia eschscholzii, Ganoderma lucidum, Ganoderma resinaceum, Phellinus pachyphloeus, Podaxis pistillaris, Lentinus squarrosulus, Lycoperdon sp et Scleroderma sp. L’analyse des données montre que le genre et l’âge des personnes interrogées n’ont pas d’influence sur la connaissance des espèces thérapeutiques. En revanche, les femmes connaissent plus d’espèces de champignons thérapeutiques que les hommes et la différence est significative entre les deux groupes. Conclusion et application des résultats : Ce premier inventaire non exhaustif des champignons thérapeutiques nous révèle une richesse insoupçonnée pour une région aride et considérée comme ayant une flore mycologique pauvre.L’étude a permis d’identifier huit espèces de champignons supérieurs médicinaux dans la ville de Ouagadougou au Burkina Faso. Ce sont : Daldinia eschscholzii, Ganoderma lucidum, Ganoderma resinaceum, Phellinus pachyphloeus, Podaxis pistillaris, Lentinus squarrosulus, Lycoperdon sp et Scleroderma sp. Il s’agit pour la plus part d’espèces lignicoles. Ces champignons supérieurs sont des agents bioactifs potentiels procurant des sources de médicaments aux populations burkinabés. Ces espèces pourraient être valorisées sur le plan thérapeutique. Leur identification constitue un préalable dans la gestion des ressources locales. Il serait aussi intéressant de mener des études plus approfondies afin de pouvoir mettre en évidence les substances bioactives en vue de leur vulgarisation.Mots clés : Mycothérapie, champignons, enquête ethnomycologique, Burkina FasoObjectives: The medicinal properties of mushrooms have been known for thousands of years, particularly through the Asian medicine. In West Africa and Burkina Faso specifically, research in this area is rare. The main objective of this study is to collect information on the use of mushrooms in traditional medicine in Burkina Faso. Methodology and results: This study was done in Ouagadougou. A quantitative questionnaire was used among 60 traditional healers (30 women and 30 men) in the central part of Burkina Faso to assess the knowledge of medicinal mushroom and how they are used. Eight mushroom species were identified in traditional medicine: Daldinia eschscholzii, Ganoderma lucidum, Ganoderma resinaceum, Phellinus pachyphloeus, Podaxis pistillaris, Lentinus squarrosulus, Lycoperdon sp and Scleroderma sp. The data analysis showed that the gender and the age of the informants have no influence on the knowledge of therapeutic species. Conclusion and application of results : This first nonexhaustive inventory of therapeutic mushrooms reveals us an unsuspected richness for an area arid and regarded as having a poor mycological flora This study have help to identify eight medicinal mushroom species in the town of Ouagadougou (Burkina Faso). This is: Daldinia eschscholzii, Ganoderma lucidum, Ganoderma resinaceum, Phellinus pachyphloeus, Podaxis pistillaris, Lentinus squarrosulus, Lycoperdon sp and Scleroderma sp. Most of them are lignicolous species.These higher mushrooms are potential bioactive agents getting sources of drugs to the burkinabé people. These species could be developed on the therapeutic level. Their identification constitutes a precondition in the local stock management.It would be also interesting to undertake studies in order to be able to highlight the bioactive substances for their popularization.Keywords: Mycotherapy, mushrooms, survey, Burkina Fas

Réponse à l’inoculation mycorhizienne de quatre variétés de niébé [Vigna unguiculata (L.) Walp.] cultivées au Burkina Faso et au Sénégal

La culture du Niébé [Vigna unguiculata (L.) Walp.] en Afrique de l’Ouest est marquée par l’instabilité de ses rendements et sa faible production liée à la pauvreté des sols, à la faiblesse de la pluviométrie et aux contraintes parasitaires. Dans cette étude, nous nous sommes intéressés à la réponse à l’inoculation mycorhizienne de quatre variétés de niébé dans une perspective de sélection de souches efficaces de champignons endomycorhiziens pour l’amélioration de sa productivité au champ. Quatre variétés de niébé dont deux du Burkina Faso [Gorom Local (GO) et KVX 396-4-5-2D (KVX)] et deux du Sénégal [Mélakh (Mel) et Yacine (Yac)] ont été inoculées en pépinière avec trois (3) inoculums mixtes du Burkina Faso [Yakouta (Ya), Talé Mossi (Ta) et Soumousso (Sou)] et trois inoculums monospécifiques de la collection du Laboratoire Commun de Microbiologie de Dakar (LCM) [Glomus mossea (Gm), Glomus fasciculatum (Gf) et Glomus intraradices (Gi)]. Les effets des différents inoculums sur la croissance des plants ont été évalués par la mesure de la hauteur des plants, des biomasses aérienne et racinaire et de la fréquence et intensité de mycorhization à la floraison et à la fructification. Les résultats obtenus montrent que l’inoculation n’a pas eu d’effets significatifs sur les différents paramètres mesurés pour les variétés du Sénégal malgré des taux demycorhization de 6% à 92% à la floraison et de 44% à 100% à la fructification. Pour les variétés du Burkina Faso, à la floraison, la croissance en hauteur et la production de biomasse aérienne de la variété KVX ont été améliorées par toutes les souches, exceptée Gm. Pour la variété GO, les inoculums mixtes indigènes Ya et Ta ont significativement amélioré la croissance en hauteur des plants. En général, les fréquences et les intensités de mycorhization sont élevées pour les souches monospécifiques, mais ceci ne se traduit pas par un effet significatif sur la croissance des plants inoculés. L’inoculum mixte indigène Ya apparaît plus performant pour la croissance en hauteur et la production de biomasse de la variété la plus sensible à l’inoculation (KVX). Cette étude a montré que l’inoculation endomycorhizienne a un effet bénéfique sur la croissance du Niébé, particulièrement la variété KVX ; et que l’utilisation de souches indigènes conviendrait mieux que les souches monospécifiques. Il s’avère donc intéressant de poursuivre la sélection de souches performantes pour la productivité du Niébé sur les souches indigènes.Mots clés: champignons mycorhiziens, croissance du Niébé, pépinière, Afrique de l’Oues

Impact of Jatropha plantation on soil chemical and biological properties in the South Sudanian region in Burkina Faso

In Burkina Faso, about 100,000 ha of Jatropha were planted during the past 10 years. Despite this enthusiasm, few results exist on the impact of the plant on soil properties. This study contributes to better knowledge of Jatropha farming and was carried out in 2013 with Jatropha farmers in Torokoro and Tin villages in the south Sudanian zone of Burkina Faso (rainfall 900-1200 mm). Data collection plots of 400 m2 repeated 3 times were installed in 3 farmers’ fields in each village. Soil samples were collected at 3 distances (D0= under the crown, D1= 1m and D2= 2m) from the Jatropha trees lines and in a fallow as a control sample for each field. The results showed significant differences between distances for soil pH. Soil nutrients increase with distance from the crown (from 9.33% to 12.20%) for available phosphorus in Torokoro-6 years and decrease from 22.45% to 23.71% in Torokoro-2 years). Soil respiration and microbial biomass decreases also with distance. The density of spores of mycorrhizal fungi is higher for the control soils (14.64%) and it decreases from crown to 2m (from 2.22% to 9.53% in Tin-2 years). The study showed the contribution of Jatropha trees on soil fertility improvement.© 2015 International Formulae Group. All rights reserved.Keywords: Jatropha, soil biology, microbial biomass, carbon, nitrogen, Burkina Fas

Reproductive Capacities and Development of a Seed Bruchid Beetle, Acanthoscelides macrophthalmus, a Potential Host for the Mass Rearing of the Parasitoid, Dinarmus basalis

The reproductive capacities and development of the seed beetle Acanthoscelides macrophthalmus (Schaeffer) (Coleoptera: Bruchidae), found in Togo, were determined under natural conditions in a Guinean zone for its use as a substitute host for the mass rearing of the parasitoid Dinarmus basalts Rond (Hymenoptera: Pteromalidae), a biological agent for the control of beetles that are pests of cowpea, Vigna unguiculata (L.) Walpers (Fabales: Fabaceae). Population dynamics at the field level; and survival, fecundity and offspring production by A. macrophthalmus under laboratory conditions were measured when fed on its natural plant-host Leucaena leucocephala (Lamark) deWit (Fabales: Mimosaceae). The data resulting from the laboratory study were used to calculate the demographic parameters of A. macrophthalmus by establishing its fertility and life tables. Contrary to cultivated leguminous food plants, L. leucocephala is a perennial sub-spontaneous leguminous plant whose pods are available year round. Although A. macrophthalmus was present in nature throughout the year, its infestation rate of the pods fluctuated according to the phenology of the plant. The maximum infestation of L. leucocephala pods was observed between August and December. Four larval stages and one pupal stage of A. macrophthalmus were identified in the laboratory. The total mean development time varied on average 33.75 ± 2.87 days on the mature pods and 33.39 ± 2.02 days on seeds. The adult female lived from one to two weeks. During its life time, the female laid an average of 62.3 ± 19 and 43.1 ± 13 eggs on the mature pods and seeds respectively and produced an average of 36.7 ± 11.3 offspring on the mature pods and 21.8 ± 8.4 offspring on seeds. On seeds, the net reproduction rate was 5.88 females per female and the intrinsic rate of population increase 0.051 per day. The generation time was 34.59 days and the doubling time 13.59 days. The demographic parameters of A. macrophthalmus in this study are close to those of Callobruchus maculatus F. (Bruchidae), the natural host of D. basalts in a previous study. A. macrophthalmus could therefore be used as substitute host for the mass rearing of D. basalts and subsequently its release in farmers' storage containers. The data presented in this study provide some baseline information regarding the reproductive capacities of A. macrophthalmus that may be useful for its promotion as a substitute host for mass rearing of D. basalts

Facultative Hyperparasitism: Extreme Survival Behaviour of the Primary Solitary Ectoparasitoid, Dinarmus basalis

This study investigated the egg-laying behaviour of ectoparsitoid, Dinarmus basalis Rondani (Hymenoptera: Pteromalidae), females when faced with a prolonged deprivation of suitable hosts leading to extreme ‘oviposition pressure’. The egg-laying behaviour of virgin D. basalis females was tested with Callosobruchus maculatus (F.) (Coleoptera: Bruchidae) hosts previously parasitized by the conspecific females in which the developing larvae had reached the last larval instar (L5) or pupae. The hyperparasitism did not prevent the occurrence of superparasitism, but only one D. basalis egg from a hyperparasitized D. basalis L5 larvae reached the adult stage due to the solitary behaviour of the D. basalis larvae. Under these experimental conditions, 60.78% of the D. basalis adults emerging from larvae were miniaturized due to the depletion of host resources

Plants used traditionally to treat malaria in Brazil: the archives of Flora Medicinal

The archives of Flora Medicinal, an ancient pharmaceutical laboratory that supported ethnomedical research in Brazil for more than 30 years, were searched for plants with antimalarial use. Forty plant species indicated to treat malaria were described by Dr. J. Monteiro da Silva (Flora Medicinal leader) and his co-workers. Eight species, Bathysa cuspidata, Cosmos sulphureus, Cecropia hololeuca, Erisma calcaratum, Gomphrena arborescens, Musa paradisiaca, Ocotea odorifera, and Pradosia lactescens, are related as antimalarial for the first time in ethnobotanical studies. Some species, including Mikania glomerata, Melampodium divaricatum, Galipea multiflora, Aspidosperma polyneuron, and Coutarea hexandra, were reported to have activity in malaria patients under clinical observation. In the information obtained, also, there were many details about the appropriate indication of each plant. For example, some plants are indicated to increase others' potency. There are also plants that are traditionally employed for specific symptoms or conditions that often accompany malaria, such as weakness, renal failure or cerebral malaria. Many plants that have been considered to lack activity against malaria due to absence of in vitro activity against Plasmodium can have other mechanisms of action. Thus researchers should observe ethnomedical information before deciding which kind of screening should be used in the search of antimalarial drugs

Differential regulation of myeloid leukemias by the bone marrow microenvironment

Like their normal hematopoietic stem cell counterparts, leukemia stem cells (LSC) in chronic myelogenous leukemia (CML) and acute myeloid leukemia (AML) are presumed to reside in specific niches in the bone marrow microenvironment (BMM)1, and may be the cause of relapse following chemotherapy.2 Targeting the niche is a novel strategy to eliminate persistent and drug-resistant LSC. CD443,4 and IL-65 have been implicated previously in the LSC niche. Transforming growth factor (TGF)-β1 is released during bone remodeling6 and plays a role in maintenance of CML LSCs7, but a role for TGF-β1 from the BMM has not been defined. Here, we show that alteration of the BMM by osteoblastic cell-specific activation of the parathyroid hormone (PTH) receptor8,9 attenuates BCR-ABL1-induced CML-like myeloproliferative neoplasia (MPN)10 but enhances MLL-AF9-induced AML11 in mouse transplantation models, possibly through opposing effects of increased TGF-β1 on the respective LSC. PTH treatment caused a 15-fold decrease in LSCs in wildtype mice with CML-like MPN, and reduced engraftment of immune deficient mice with primary human CML cells. These results demonstrate that LSC niches in chronic and acute myeloid leukemias are distinct, and suggest that modulation of the BMM by PTH may be a feasible strategy to reduce LSC, a prerequisite for the cure of CML

Quantification of uncertainties in global grazing systems assessments

Livestock systems play a key role in global sustainability challenges like food security and climate change, yet, many unknowns and large uncertainties prevail. We present a systematic, spatially explicit assessment of uncertainties related to grazing intensity (GI), a key metric for assessing ecological impacts of grazing, by combining existing datasets on a) grazing feed intake, b) the spatial distribution of livestock, c) the extent of grazing land, and d) its net primary productivity (NPP). An analysis of the resulting 96 maps implies that on average 15% of the grazing land NPP is consumed by livestock. GI is low in most of worlds grazing lands but hotspots of very high GI prevail in 1% of the total grazing area. The agreement between GI maps is good on one fifth of the world's grazing area, while on the remainder it is low to very low. Largest uncertainties are found in global drylands and where grazing land bears trees (e.g., the Amazon basin or the Taiga belt). In some regions like India or Western Europe massive uncertainties even result in GI > 100% estimates. Our sensitivity analysis indicates that the input-data for NPP, animal distribution and grazing area contribute about equally to the total variability in GI maps, while grazing feed intake is a less critical variable. We argue that a general improvement in quality of the available global level datasets is a precondition for improving the understanding of the role of livestock systems in the context of global environmental change or food security

Sub region-specific modulation of synchronous neuronal burst firing after a kainic acid insult in organotypic hippocampal cultures

<p>Abstract</p> <p>Background</p> <p>Excitotoxicity occurs in a number of pathogenic states including stroke and epilepsy. The adaptations of neuronal circuits in response to such insults may be expected to play an underlying role in pathogenesis. Synchronous neuronal firing can be induced in isolated hippocampal slices and involves all regions of this structure, thereby providing a measure of circuit activity. The effect of an excitotoxic insult (kainic acid, KA) on Mg²⁺-free-induced synchronized neuronal firing was tested in organotypic hippocampal culture by measuring extracellular field activity in CA1 and CA3.</p> <p>Results</p> <p>Within 24 hrs of the insult regional specific changes in neuronal firing patterns were evident as: (i) a dramatic <it>reduction </it>in the ability of CA3 to generate firing; and (ii) a contrasting <it>increase </it>in the frequency and duration of synchronized neuronal firing events in CA1. Two distinct processes underlie the increased propensity of CA1 to generate synchronized burst firing; a lack of ability of the CA3 region to 'pace' CA1 resulting in an increased frequency of synchronized events; and a change in the 'intrinsic' properties limited to the CA1 region, which is responsible for increased event duration. Neuronal quantification using NeuN immunoflurescent staining and stereological confocal microscopy revealed no significant cell loss in hippocampal sub regions, suggesting that changes in the properties of neurons within this region were responsible for the KA-mediated excitability changes.</p> <p>Conclusion</p> <p>These results provide novel insight into adaptation of hippocampal circuits following excitotoxic injury. KA-mediated disruption of the interplay between CA3 and CA1 clearly increases the propensity to synchronized firing in CA1.</p