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P. chevalieri (Asteraceae) est utilisé en médecine traditionnelle contre le paludisme à Bukavu et à Uvira en RDC. Cette étude rapporte pour la première fois son activité antiplasmodiale et l'isolement chromatographique bio-guidé de certains de ses métabolites secondaires. De plus, sa propriété antioxydante et son effet cytotoxique ont été étudiés. La plante à l’étude a été sélectionnée sur base des enquêtes ethnobotaniques menées sous-forme d’interview directe auprès de 32 tradipraticiens des 2 villes précitées. Les extraits de feuilles de la plante obtenus par percolation suivant une polarité croissante des solvants ont été testés in vitro sur les souches plasmodiales chloroquinosensibles (3D7) et chloroquinorésistantes (W2) par la mesure du plasmodium lactate déshydrogénase. Leur cytotoxicité a également été testée par MTT sur les kératinocytes HaCat alors que leur pouvoir antioxydant a été effectué selon les méthodes au DPPH et FRAP. Le fractionnement bioguidé et l’isolement ont été entrepris par chromatographie. La structure de la molécule isolée a été établie par spectroscopie RMN et de masse. L’extrait méthanolique s’est révélé le plus actif sur les 2 souches plasmodiales testées (CI50 < 7 µg/ml) et non cytotoxique avec un pouvoir antioxydant intéressant. Son fractionnement bioguidé a permis d’isoler une molécule active (CI50 < 5 µg/ml) identifiée comme étant la rutine. La présence de la rutine dans P. chevalieri pourrait expliquer à la fois ses activités antiplasmodiales et antioxydantes, par conséquent son utilisation comme antipaludéen., IntroductionCette étude a été entreprise afin de contribuer à la lutte contre le paludisme et de valoriser par des preuves scientifiques les connaissances ancestrales sur les plantes médicinales congolaises à vertus antipaludéennes. Elle part de travaux d’enquête ethnobotanique effectuée à Bukavu et Uvira au Sud-Kivu en RDC jusqu’aux analyses au laboratoire en rapport avec les tests d’activités antiplasmodiale et antioxydante d’une plante sélectionnée parmi 45 plantes enregistrées au cours des enquêtes tout en évaluant sa cytotoxicité sur des cellulaires humaines, et met en évidence également les différents constituants phytochimiques de cette plante et permet l’isolement d’un flavonoïde probablement responsable de ses effets pharmacologiques étudiées.État de l’artDans la quête de nouveaux médicaments antipaludéens, l’approche ethnobotanique est une alternative très crédible pour trois raisons suivantes :(i) les résultats remarquables de travaux antérieurs tant dans la mise au point de médicaments traditionnels améliorés comme Manalarial 5® [1] et la découverte de médicaments modernes à partir des plantes médicinales à l’image de la quinine, isolée de Cinchona officinalis L. [2] et de l’artémisinine, isolée de Artemisia annua L. [3] ;(ii) les habitudes socio-culturelles qui justifient un grand recours à la médecine traditionnelle dans le traitement du paludisme [4] ;(iii) l’accessibilité physique et économique qu’offre la médecine traditionnelle [5]. Selon la littérature sur les plantes antipaludéennes africaines, les familles botaniques telles que Asteraceae, Combretaceae, Fabaceae et Rubiaceae se sont illustrées [6,7] et les groupes phytochimiques comme des alcaloïdes, terpénoïdes, flavonoïdes et stéroïdes se sont révélés très prometteurs [8]. En RDC, des études ont été menées sur des plantes antipaludéennes dans plusieurs provinces [4,9]. Cependant, au Sud-Kivu (surtout à Bukavu et Uvira), peu de travaux se sont intéressés à cette catégorie des plantes médicinale, info:eu-repo/semantics/nonPublished

Les infections microbiennes causées par des agents pathogènes résistants aux thérapies sont en hausse dans le monde. Ce problème touche non seulement les pays développés mais surtout les pays en voie de développement. Dans les milieux ruraux, les habitants n’ont pas accès aux conditions sanitaires appropriées. La majorité des hôpitaux de l’Afrique sub-saharienne sont cités parmi les plus faibles du monde en termes de qualité de soins et de moyens disponibles. La prolifération des officines pharmaceutiques « clandestines » qui échappent au contrôle des États minés par la corruption et le laxisme est un signe de la difficulté d’apporter des solutions satisfaisantes aux problèmes de la population. Cet état de fait entraine un trafic frauduleux et un large usage de « faux médicaments » par la population. Le manque de traitements efficaces est l’une des causes des maladies infectieuses présentant une résistance aux antibiotiques. Face à ces fléaux, il est nécessaire de développer de nouveaux agents antimicrobiens.Les acides hydroxamiques (AH) présentent diverses propriétés biologiques contre les bactéries, les champignons, les virus et les cellules cancéreuses. Ils sont aussi de puissants inhibiteurs d’enzymes tels que les hydrolases, l’uréase, la tyrosinase, l’élastase, l’aminopeptidase, les peroxydases, les métalloprotéinases, les histones déacétylases, la peptide déformylase et les anhydrases carboniques. L'activité antimicrobienne des AH convertis en leurs chélates métalliques est améliorée par rapport aux composés non-complexés. La fonction hydroxamate est souvent décrite comme étant à l’origine de l’activité biologique. Cependant, la lipophilie et le type de métal de coordination dans les complexes pourraient être des éléments importants influençant les activités antimicrobiennes de ces composés chimiques.C’est dans cette optique que nous avons synthétisé et caractérisé quarante-deux composés dont six AH et trente-six complexes de Fe (II/III), de Ni (II), de Cu (II, Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie), info:eu-repo/semantics/nonPublished

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We aimed to evaluate the potential of traditionally used Pakistani plants for inflammatory bowel diseases and to identify their active constituents. Starting from 5 Pakistani plants, we obtained 25 non-cytotoxic extracts of which 5 showed an interesting activity in decreasing pro-inflammatory cytokines expression in LPS-activated J774 macrophages. Among these, the methanol extract of Salvadora oleoides underwent a bio-guided fractionation and one of the most active fractions, dereplicated by HPLC-HRMS/MS analysis, was putatively found rich in galactolipids that could be responsible for at least a part of the observed activity. The extract was also found to be not toxic by in vivo acute and sub-acute toxicity tests and was tested, per os, in a DSS-induced colitis mice model, but did not reduce the extent of colon inflammation. We also investigated the methanol and ethyl acetate extracts of Convolvulus arvensis and putatively identified 45 compounds by dereplication (HPLC-HRMS/MS analysis and molecular networking). The 6 major compounds were quantified by HPLC-PDA in both extracts and 4 of them were found to significantly decrease LPS-induced J774 macrophage activation, supporting the traditional use of the plant., (BIFA - Sciences biomédicales et pharmaceutiques) -- UCL, 2022

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Cardiovascular diseases (CVD) and cancers are the two main causes of death worldwide. The initiation and progression of atherosclerosis is, in large part, caused by oxidized low-density lipoproteins (oxLDL); interestingly, oxLDL may also play a role in cancer cell metabolism and migration. As oxLDL are generally obtained by tedious ultracentrifugation procedures, “home-made” oxLDL were obtained by (i) applying a purification kit to isolate LDL and VLDL from human plasma; (ii) isolating LDL from VLDL by gel permeation chromatography (GPC); and (iii) oxidating LDL through CuSO4 incubation. On three HPV-positive head and neck cancer cells (HNCC) (93VU-147T, UM-SCC47, and UPCI-SCC154), cell migration was assessed using Boyden chambers, the Wnt/ß-catenin pathway was analyzed by Western Blotting, and the expression of two oxLDL receptors, LOX-1 and CD36, in response to oxLDL exposure, was analysed by immunofluorescence. Our data indicate: (a) a non-significant difference between reference and “home-made” oxLDL; (b) a decreased migration, parallel to an inhibition of the ß-catenin pathway; and (c) an increase of CD36 and LOX-1 expression in all HNCC. In conclusion, we successfully produced oxLDL. Our results demonstrate a decrease in HNCC migration after oxLDL exposure, and an increased expression of LOX-1 and CD36 associated with lipid uptake., SCOPUS: ar.j, info:eu-repo/semantics/published

The selection of appropriate food resources by bees is a critical aspect for the maintenance of their populations, especially in the current context of global change and pollinator decline. Wild bees have a sophisticated ability to forage selectively on specific resources, and can assess the quality of pollen using contact chemosensory perception (taste). While numerous studies have investigated the detection of pollen macronutrients in bees and their impact on bee health and reproductive success, only a few studies have described the gustatory responses of bees toward specialized metabolites. In addition, these studies mostly focused on the response to nectar and neglected pollen, which is the main food resource for both bee imagines and larvae. Whether bees have the ability to detect specialized toxic metabolites in pollen and then rapidly adapt their foraging behavior to avoid them is very little studied. In this study, we tested whether pollen specialized metabolites affect bumblebees at both the micro-colony and individual levels (i.e., bioassays using supplemented pollen), and whether foragers detect these specialized metabolites and potentially display an avoidance behavior (i.e., preference tests using supplemented syrup). Bumblebees were fed with either amygdalin-, scopolamine- or sinigrin-supplemented pollen diets in ratios that mimic 50%, 100%, and 200% of naturally occurring concentrations. We found no effect of these specialized metabolites on resource collection, reproductive success and stress response at the micro-colony level. At the individual level, bumblebees fed on 50%-amygdalin or 50%-scopolamine diets displayed the highest scores for damage to their digestive systems. Interestingly, during the preference tests, the solution with 50%-scopolamine displayed a phagostimulatory activity, whereas solution with 50%-amygdalin had a deterrent effect and could trigger an active avoidance behavior in bumblebees, with a faster proboscis retraction. Our re

The selection of appropriate food resources by bees is a critical aspect for the maintenance of their populations, especially in the current context of global change and pollinator decline. Wild bees have a sophisticated ability to forage selectively on specific resources, and can assess the quality of pollen using contact chemosensory perception (taste). While numerous studies have investigated the detection of pollen macronutrients in bees and their impact on bee health and reproductive success, only a few studies have described the gustatory responses of bees toward specialized metabolites. In addition, these studies mostly focused on the response to nectar and neglected pollen, which is the main food resource for both bee imagines and larvae. Whether bees have the ability to detect specialized toxic metabolites in pollen and then rapidly adapt their foraging behavior to avoid them is very little studied. In this study, we tested whether pollen specialized metabolites affect bumblebees at both the micro-colony and individual levels (i.e., bioassays using supplemented pollen), and whether foragers detect these specialized metabolites and potentially display an avoidance behavior (i.e., preference tests using supplemented syrup). Bumblebees were fed with either amygdalin-, scopolamine- or sinigrin-supplemented pollen diets in ratios that mimic 50%, 100%, and 200% of naturally occurring concentrations. We found no effect of these specialized metabolites on resource collection, reproductive success and stress response at the micro-colony level. At the individual level, bumblebees fed on 50%-amygdalin or 50%-scopolamine diets displayed the highest scores for damage to their digestive systems. Interestingly, during the preference tests, the solution with 50%-scopolamine displayed a phagostimulatory activity, whereas solution with 50%-amygdalin had a deterrent effect and could trigger an active avoidance behavior in bumblebees, with a faster proboscis retraction. Our re

The selection of appropriate food resources by bees is a critical aspect for the maintenance of their populations, especially in the current context of global change and pollinator decline. Wild bees have a sophisticated ability to forage selectively on specific resources, and can assess the quality of pollen using contact chemosensory perception (taste). While numerous studies have investigated the detection of pollen macronutrients in bees and their impact on bee health and reproductive success, only a few studies have described the gustatory responses of bees toward specialized metabolites. In addition, these studies mostly focused on the response to nectar and neglected pollen, which is the main food resource for both bee imagines and larvae. Whether bees have the ability to detect specialized toxic metabolites in pollen and then rapidly adapt their foraging behavior to avoid them is very little studied. In this study, we tested whether pollen specialized metabolites affect bumblebees at both the micro-colony and individual levels (i.e., bioassays using supplemented pollen), and whether foragers detect these specialized metabolites and potentially display an avoidance behavior (i.e., preference tests using supplemented syrup). Bumblebees were fed with either amygdalin-, scopolamine- or sinigrin-supplemented pollen diets in ratios that mimic 50%, 100%, and 200% of naturally occurring concentrations. We found no effect of these specialized metabolites on resource collection, reproductive success and stress response at the micro-colony level. At the individual level, bumblebees fed on 50%-amygdalin or 50%-scopolamine diets displayed the highest scores for damage to their digestive systems. Interestingly, during the preference tests, the solution with 50%-scopolamine displayed a phagostimulatory activity, whereas solution with 50%-amygdalin had a deterrent effect and could trigger an active avoidance behavior in bumblebees, with a faster proboscis retraction. Our re

The selection of appropriate food resources by bees is a critical aspect for the maintenance of their populations, especially in the current context of global change and pollinator decline. Wild bees have a sophisticated ability to forage selectively on specific resources, and can assess the quality of pollen using contact chemosensory perception (taste). While numerous studies have investigated the detection of pollen macronutrients in bees and their impact on bee health and reproductive success, only a few studies have described the gustatory responses of bees toward specialized metabolites. In addition, these studies mostly focused on the response to nectar and neglected pollen, which is the main food resource for both bee imagines and larvae. Whether bees have the ability to detect specialized toxic metabolites in pollen and then rapidly adapt their foraging behavior to avoid them is very little studied. In this study, we tested whether pollen specialized metabolites affect bumblebees at both the micro-colony and individual levels (i.e., bioassays using supplemented pollen), and whether foragers detect these specialized metabolites and potentially display an avoidance behavior (i.e., preference tests using supplemented syrup). Bumblebees were fed with either amygdalin-, scopolamine- or sinigrin-supplemented pollen diets in ratios that mimic 50%, 100%, and 200% of naturally occurring concentrations. We found no effect of these specialized metabolites on resource collection, reproductive success and stress response at the micro-colony level. At the individual level, bumblebees fed on 50%-amygdalin or 50%-scopolamine diets displayed the highest scores for damage to their digestive systems. Interestingly, during the preference tests, the solution with 50%-scopolamine displayed a phagostimulatory activity, whereas solution with 50%-amygdalin had a deterrent effect and could trigger an active avoidance behavior in bumblebees, with a faster proboscis retraction. Our re

The selection of appropriate food resources by bees is a critical aspect for the maintenance of their populations, especially in the current context of global change and pollinator decline. Wild bees have a sophisticated ability to forage selectively on specific resources, and can assess the quality of pollen using contact chemosensory perception (taste). While numerous studies have investigated the detection of pollen macronutrients in bees and their impact on bee health and reproductive success, only a few studies have described the gustatory responses of bees toward specialized metabolites. In addition, these studies mostly focused on the response to nectar and neglected pollen, which is the main food resource for both bee imagines and larvae. Whether bees have the ability to detect specialized toxic metabolites in pollen and then rapidly adapt their foraging behavior to avoid them is very little studied. In this study, we tested whether pollen specialized metabolites affect bumblebees at both the micro-colony and individual levels (i.e., bioassays using supplemented pollen), and whether foragers detect these specialized metabolites and potentially display an avoidance behavior (i.e., preference tests using supplemented syrup). Bumblebees were fed with either amygdalin-, scopolamine- or sinigrin-supplemented pollen diets in ratios that mimic 50%, 100%, and 200% of naturally occurring concentrations. We found no effect of these specialized metabolites on resource collection, reproductive success and stress response at the micro-colony level. At the individual level, bumblebees fed on 50%-amygdalin or 50%-scopolamine diets displayed the highest scores for damage to their digestive systems. Interestingly, during the preference tests, the solution with 50%-scopolamine displayed a phagostimulatory activity, whereas solution with 50%-amygdalin had a deterrent effect and could trigger an active avoidance behavior in bumblebees, with a faster proboscis retraction. Our re

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Monolignols are the building blocks for lignin polymerization in the apoplastic domain. Monolignol biosynthesis, transport, storage, glycosylation, and deglycosylation are the main biological processes partaking in their homeostasis. In Arabidopsis thaliana, members of the uridine diphosphate-dependent glucosyltransferases UGT72E and UGT72B subfamilies have been demonstrated to glycosylate monolignols. Here, the poplar UGT72 family, which is clustered into four groups, was characterized: Group 1 UGT72AZ1 and UGT72AZ2, homologs of Arabidopsis UGT72E1-3, as well as group 4 UGT72B37 and UGT72B39, homologs of Arabidopsis UGT72B1-3, glycosylate monolignols. In addition, promoter-GUS analyses indicated that poplar UGT72 members are expressed within vascular tissues. At the subcellular level, poplar UGT72s belonging to group 1 and group 4 were found to be associated with the nucleus and the endoplasmic reticulum. However, UGT72A2, belonging to group 2, was localized in bodies associated with chloroplasts, as well as possibly in chloroplasts. These results show a partial conservation of substrate recognition between Arabidopsis and poplar homologs, as well as divergent functions between different groups of the UGT72 family, for which the substrates remain unknown., SCOPUS: ar.j, info:eu-repo/semantics/published

Ethnopharmacological relevance: The main objective of the present study was to collect and gather information on herbal remedies traditionally used for the treatment of malaria in Bukavu and Uvira, two towns of the South Kivu province in DRC. Material and methods: Direct interview with field enquiries allowed collecting ethnobotanical data; for each plant, a specimen was harvested in the presence of the interviewed traditional healers (THs). The recorded information included vernacular names, morphological parts of plants, methods of preparation and administration of remedies, dosage and treatment duration. Plants were identified with the help of botanists in the herbaria of INERA/KIPOPO (DRC) and the Botanic Garden of Meise (Belgium), where voucher specimens have been deposited. The results were analysed and discussed in the context of previous published data. Results: Interviewees cited 45 plant species belonging to 41 genera and 21 families used for the treatment of malaria. These plants are used in the preparation of 52 recipes, including 25 multi-herbal recipes and 27 mono-herbal recipes. Apart of Artemisia annua L. (Asteraceae; % Citation frequency = 34%) and Carica papaya L. (Caricaceae; % Citation frequency = 34%), the study has highlighted that the most represented families are Asteraceae with 12 species (26%), followed by Fabaceae with 7 species (16%) and Rubiaceae with 4 species (9%). For a majority of plants, herbal medicines are prepared from the leaves in the form of decoction and administered by oral route. Conclusion: Literature data indicate that part of cited species are already known (38%) and/or studied (30%) for antimalarial properties, which gives credit to the experience of Bukavu and Uvira interviewees and some level of confidence on collected information. The highly cited plants should be investigated in details for the isolation and identification of active ingredients, a contribution to the discovery of new possibly effective antimalarials, SCOPUS: ar.j, info:eu-repo/semantics/published

Le paludisme, par sa forte prévalence et morbidité, constitue l'une de principales maladies parasitaires tropicales, particulièrement en RD Congo. Sa thérapie recourt non seulement aux antipaludéens modernes qui, pour la plupart sont sujets des résistances, mais aussi aux plantes médicinales, sources de nombreux antipaludéens efficaces. Ainsi, cette étude a recensé les plantes et les recettes réputées antipaludéennes dans la région de Bukavu et d’Uvira, sélectionné l’une d’elles pour une étude phytochimique et pharmacologique approfondie en vue de mettre en évidence ses potentialités thérapeutiques pouvant permettre le développement potentiel d’un médicament antipaludéen. L’enquête ethnobotanique, menée sous forme d’interview directe auprès de 32 tradipraticiens d’âge moyen 55 ± 13 ans, de sexe ratio homme-femme de 1,7, d’expérience moyenne de métier de 18 ± 8 ans, sélectionnés après un sondage auprès de 192 habitants (62 % de femmes) pris au hasard sur le marché dans chaque localité, a permis de recenser 45 espèces de plantes, appartenant à 41 genres et 21 familles, utilisées pour le traitement du paludisme. Les familles les plus représentées sont les Asteraceae avec 12 espèces (26 %), les Fabaceae avec 7 espèces (16 %) et les Rubiaceae avec 4 espèces (9 %). Ces plantes permettent la préparation de 52 recettes dont 25 recettes multi-herbes et 27 recettes mono-herbes. La majorité de ces recettes sont préparées à partir de feuilles sous forme de décoction et sont administrées par voie orale.Parmi les 23 espèces végétales les plus citées (3 citations au minimum) par les personnes ressources interrogées, 7 plantes ont été encore peu étudiées dans le domaine du paludisme selon la littérature à notre disposition. Les tests antiplasmodiaux in vitro, selon la méthode microscopique de Rickman, réalisés sur les extraits méthanoliques de 7 plantes a permis de sélectionner 4 plantes actives dont Fadogiella stigmatoloba (K.Schum.) Robyns (Rubiaceae ;feuilles :CI50 = 13,6 ± 1,2, Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie), info:eu-repo/semantics/nonPublished

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La sphaeropsidine A est une phytotoxine fongique extraite du Diplodia cupressi ayant montré des effets anti-cancéreux in vitro à des concentrations de l’ordre du micromolaire. En perturbant l’équilibre ionique, notamment via une inhibition des co-transporteurs Na+, K+, 2Cl- (NKCC-1) et/ou possiblement des échangeurs anioniques de type Cl-/HCO3-, elle provoque une réduction du volume cellulaire et empêche le processus de « regulatory volume increase » qui vise à rétablir l’homéostasie cellulaire lors de l’apoptose. Néanmoins, une étude physico-chimique a montré que la sphaeropsidine A est très peu soluble en milieu aqueux et qu’elle se dégrade rapidement à 37 °C rendant ainsi difficile dans ces conditions, son évaluation in vivo non seulement du point de vue de son efficacité thérapeutique mais aussi de sa toxicité.Au cours de ce travail, nous avons poursuivi l’évaluation de l’activité anti-cancéreuse in vitro de la sphaeropsidine A en envisageant son utilisation en combinaison avec des composés chimiothérapeutiques pro-apoptotiques (le cisplatine et le témozolomide) en vue de contrer les phénomènes de résistance des cellules de mélanomes à ces traitements. Ces travaux sont basés sur une étude publiée par(Algharabil et al. 2012)ayant montré l’intérêt de combiner au témozolomide le bumétanide, un inhibiteur spécifique de NKCC-1 inhibant également le processus de « regulatory volume increase » au sein de gliomes. Pour rationaliser l’approche combinatoire, nous avons utilisé un plan d’expérience factoriel et avons créé un modèle prédictif basé sur le modèle statistique des surfaces de réponses. Ainsi, nous avons pu déterminer les combinaisons capables d’induire un maximum de cytotoxicité sur notre modèle d’intérêt. Les résultats obtenus confirment que la sphaeropsidine A pourrait potentialiser la cytotoxicité induite par le cisplatine et le témozolomide sur les cellules de mélanomes. Ces résultats ont fait l’objet d’une validation des combinaisons prédites sur base du m, Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie), info:eu-repo/semantics/nonPublished

Ethnopharmacological relevance: The main objective of the present study was to collect and gatherinformation on herbal remedies traditionally used for the treatment of malaria in Bukavu and Uvira, twotowns of the South Kivu province in DRC.Material and methods: Direct interview with field enquiries allowed collecting ethnobotanical data; foreach plant, a specimen was harvested in the presence of the interviewed traditional healers (THs). Therecorded information included vernacular names, morphological parts of plants, methods of preparationand administration of remedies, dosage and treatment duration. Plants were identified with the help ofbotanists in the herbaria of INERA/KIPOPO (DRC) and the Botanic Garden of Meise (Belgium), wherevoucher specimens have been deposited. The results were analysed and discussed in the context ofprevious published data.Results: Interviewees cited 45 plant species belonging to 41 genera and 21 families used for the treatmentof malaria. These plants are used in the preparation of 52 recipes, including 25 multi-herbal recipes and27 mono-herbal recipes. Apart of Artemisia annua L. (Asteraceae; % Citation frequency = 34 %) andCarica papaya L. (Caricaceae; % Citation frequency = 34 %), the study has highlighted that the mostrepresented families are Asteraceae with 12 species (26 %), followed by Fabaceae with 7 species (16 %)and Rubiaceae with 4 species (9 %). For a majority of plants, herbal medicines are prepared from theleaves in the form of decoction and administered by oral route.Conclusion: Literature data indicate that part of cited species are already known (38 %) and/or studied (30%) for antimalarial properties, which gives credit to the experience of Bukavu and Uvira interviewees andsome level of confidence on collected information. The highly cited plants should be investigated indetails for the isolation and identification of active ingredients, a contribution to the discovery of newpossibly effective antimalarials., info:eu-repo/semantics/published

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Background: Hydroxyurea (HU) reduces the severity of sickle cell disease (SCD) in children; nevertheless, its long-term safety is an important concern. This paper evaluates HU genotoxicity at dose ≤ 30 mg/kg/day after over 2 years of treatment. Procedure: The study included 76 children: 32 SCD patients treated with HU, 27 SCD patients not treated with HU, and 17 unaffected children. HU patients were classified as good or poor responders according to their clinical response. Comet assay allows the comparison of DNA damage between both groups of patients and unaffected children. Maximal concentration (Cmax) of HU in plasma was determined after drug administration. Results: Mean values of DNA in the comet tail were 5.13 ± 6.84 for unaffected children, 5.80 ± 7.78 for patients with SCD treated with HU, and 5.61 ± 6.91 for patients with SCD not treated with HU. Significant differences were observed between unaffected children and children with SCD. No difference was evident between comets from SCD patients treated and not treated with HU. In the case of HU, mean DNA in the comet tail was significantly lower in good responders than in poor responders: 5.54 ± 7.77 and 6.69 ± 8.43, respectively. Mean Cmax value on plasma was 39.08 ± 15.65 mg/l; N = 31. Conclusions: SCD increases, slightly but significantly, DNA damage in lymphocytes from patients with SCD. Patients with SCD treated with HU do not present more nucleoid damage than patients with SCD not treated with HU. Good responders to the HU treatment have significantly less nucleoid damage than poor responders. HU treatment at ≤30 mg/kg/day does not expose patients to a genotoxic plasma concentration., SCOPUS: ar.j, info:eu-repo/semantics/published

BackgroundL’insécurité alimentaire et les problèmes nutritionnels sont une réalité à laquelle font face la population congolaise en général et les groupes à risque en particulier. La République Démocratique du Congo (RDC) par l’entremise du Programme National de Nutrition (PRONANUT) ainsi que ses différents partenaires cherchent des pistes de solutions pour améliorer l’état nutritionnel des personnes les plus exposées. Ces solutions sont passées entre autres par la révision de la politique en matière de nutrition, améliorant les capacités des prestataires pour une meilleure prise en charge de la malnutrition, et encourageant les recherches d’intervention nutritionnelle sur les produits locaux ayant des vertus nutritionnelles. L’objectif principal de cette recherche était de contribuer à l’amélioration de la prise en charge globale des PVVIH suivies sous traitement antirétroviral dans un centre de traitement ambulatoire (CTA) de Kinshasa, RDC par l’étude des problèmes nutritionnels et la supplémentation à la poudre de feuilles de M.O. spécifiquement il s’agissait d’identifier les facteurs déterminant l’état nutritionnel des PVVIH suivies dans un CTA à Kinshasa. De déterminer le profil épidémiologique, clinique ainsi que l’évolution de l’état nutritionnel des PVVIH éligibles dans cette recherche. De déterminer les valeurs nutritionnelles de la poudre de feuilles de Moringa oleifera (M.O) cultivé à Kinshasa, RDC. Et enfin d’évaluer l’impact de la supplémentation à la poudre de feuilles de M.O versus les conseils nutritionnels sur l’état nutritionnel et immunologique, globalement et en fonction de certaines caractéristiques des PVVIH suivies sous traitement antirétroviral dans cette étudeMéthodologie Les différentes études que nous avons menées, ont été réalisées dans le centre de traitement ambulatoire (CTA) des PVVIH de l’Organisation Non Gouvernementale (ONG) « Action Communautaire Sida et Avenir Meilleur pour les Orphelins en RDC » (ACS/AMOCONGO). Quatre études ont, Doctorat en Santé Publique, info:eu-repo/semantics/nonPublished

Traditional Malagasy farmers have developed a range of biological methods to restrict plant diseases without reliance on external or synthetic inputs. Five common Malagasy traditional practices demonstrated to be efficient against potato crop bacterial disease in experimental fields have been investigated for their antibacterial (i.e. bacteriostatic and bactericidal effects) and anti-virulence (i.e. antiquorum sensing and anti-biofilm) activities against two phytopathogens, Pseudomonas aeruginosa and Ralstonia solanacearum. Results show that polar (methanolic) extracts of recipes exert anti-virulence activities rather than bacteriostatic and/or bactericidal activities. Indeed, three recipes (R5, R7 and R9) reduce the expression of QS-dependent virulence factors whereas only recipe (R5) exhibit antibiofilm activities without affecting bacterial growth. R4 and R6 were not active, suggesting other bacterial targets and/or other bioactivity properties. Innovative approaches, inspired from ancestral practices, should be considered in the struggle against infectious diseases to limit the overuse of antibiotics for controlling infectious plant diseases and to reduce the overspread of multidrug resistant bacteria., SCOPUS: ar.j, info:eu-repo/semantics/published

Introduction Peganum harmala L. (P. harmala) is broadly used in folk medicine for the treatment of various diseases including cancer. The seeds in particularly are employed for therapeutic purposes. The present paper investigates the cytotoxic effects of raw alkaloid extracts from different parts of P. harmala including fruits (TAFr), seeds (TASe), roots (TAR) and aerial parts (TAAp); in order to assess traditional claims about the therapeutic potential of this plant. Methods The cytotoxic effects were evaluated on six malignant cancer cells (A549, U373, Hs683, MCF7, B16F10 and SKMEL-28; A549, U373, MCF7 and SKMEL-28 which are resistant to proapoptotic stimuli) by MTT assay and quantitative videomicroscopy analysis. The main alkaloids were quantified by HPLC in the different parts of plant. Results Total alkaloids of the different parts were cytotoxic towards practically all cancer cell lines with IC50 ranging 1–52 μg/mL after 72 h of treatment. Videomicroscopy analysis indicated that the TAFr, TASe and TAR alkaloids affect A549 lung carcinoma cells behaviour and induce a cytostatic effect whereas TAAp extract was cytotoxic rather than cytostatic. TAAp, TAFr, TASe and TAR treatment induced global growth ratio indexes (GGR) of 0.19, 0.26, 0.3 and 0.62, respectively, after 72 h of treatment. Depending on the organe, harmine, harmaline, harmol and vasicine these range between 2 and 90% w/w of the total alkaloids. Conclusion These data indicate that P. harmala alkaloids extract may support the traditional claims regarding its anticancer uses which could be helpful in providing of new cytotoxic agents against chemo-resistant cancer cells., SCOPUS: ar.j, info:eu-repo/semantics/published

The emergence of antimicrobial resistant infectious diseases remains a major threat to worldwide public health, in developed and in developing countries. Therefore, new antimicrobial agents acting by new mechanisms of action are urgently needed. As plants used in traditional medicine may help to overcome these problems, Justicia subsessilis, Platostoma rotundifolium, Pavetta ternifolia, Stomatanthes africanus, and Virectaria major (plants highly cited to be used against microbial infections in traditional Burundian medicine) were studied to assess their traditional use efficacy. We conducted a preliminary phytochemical screening of the extracts, as well as their direct and indirect (effect on antibiotic resistance) antibacterial activity on four bacterial strains (Staphylococcus sp. and Escherichia coli) by broth microdilution methods. All five medicinal plants investigated in this work were found to have direct antibacterial activity against all tested bacterial strains (minimum inhibitory concentration = 62.5–1000 μg/mL) that may support the use of these species in traditional Burundian medicine. Extracts (with no direct antibacterial activity), tested at 200 μg/mL, decreased the MIC values of β-lactams and aminoglycoside antibiotics by a factor of 2 to 64-fold. These interactions between plant extracts and antibiotics could open an avenue of research against antibiotic resistance. Copyright © 2017 John Wiley & Sons, Ltd., SCOPUS: ar.j, info:eu-repo/semantics/published

Platostoma rotundifolium (Briq.) A. J. Paton aerial parts are widely used in Burundi traditional medicine to treat infectious diseases. In order to investigate their probable antibacterial activities, crude extracts from P. rotundifolium were assessed for their bactericidal and anti-virulence properties against an opportunistic bacterial model, Pseudomonas aeruginosa PAO1. Whereas none of the tested extracts exert bacteriostatic and/or bactericidal proprieties, the ethyl acetate and dichloromethane extracts exhibit anti-virulence properties against Pseudomonas aeruginosa PAO1 characterized by an alteration in quorum sensing gene expression and biofilm formation without affecting bacterial viability. Bioguided fractionation of the ethyl acetate extract led to the isolation of major anti-virulence compounds that were identified from nuclear magnetic resonance and high-resolution molecular spectroscopy spectra as cassipourol, β-sitosterol and α-amyrin. Globally, cassipourol and β-sitosterol inhibit quorum sensing-regulated and -regulatory genes expression in las and rhl systems without affecting the global regulators gacA and vfr, whereas α-amyrin had no effect on the expression of these genes. These terpenoids disrupt the formation of biofilms at concentrations down to 12.5, 50 and 50 µM for cassipourol, β-sitosterol and α-amyrin, respectively. Moreover, these terpenoids reduce the production of total exopolysaccharides and promote flagella-dependent motilities (swimming and swarming). The isolated terpenoids exert a wide range of inhibition processes, suggesting a complex mechanism of action targeting P. aeruginosa virulence mechanisms which support the wide anti-infectious use of this plant species in traditional Burundian medicine., SCOPUS: ar.j, info:eu-repo/semantics/published

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In 2012, the World Health Organization (WHO) recorded 14 million new cases of cancer and 8.2 million cancer-related deaths. Remarkably, the WHO estimates that 30 % of cancer mortalities are due to lifestyle choices and environmental factors that can and should be avoided. In line with these recommendations, this chapter discusses the genotoxicity and carcinogenicity of herbal products. Although often perceived as innocuous by the general public, many herbs harbor phytochemicals that are either directly reactive towards DNA or likely to disturb cellular homeostasis, cell cycle, and/or genome maintenance mechanisms; this may translate into genotoxicity, carcinogenicity, or co-carcinogenicity. Genotoxicity refers to the deleterious effect of a chemical compound or a physical event on the genetic material; such genotoxic events are considered hallmarks of cancer risk. Nevertheless, much of the damage to the genetic material can be efficiently bypassed and/or repaired by the numerous genome maintenance mechanisms of the cell and may not lead to cancer. The long-term safety evaluation is probably better investigated through carcinogenicity, which denotes the capacity of a chemical substance or a mixture of chemical substances to induce cancer or increase its incidence. The major mechanisms of carcinogenicity are discussed along with biomarkers and approved regulatory guidelines. The recent development of innovative carcinogenicity testing strategies, especially based on functional genomics, are debated and evaluated for possible application to the precocious evaluation of herbal products’ long-term safety. Finally, this chapter provides some examples of proven or suspected carcinogenic herbal products reported in the current literature., SCOPUS: ch.b, info:eu-repo/semantics/published

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The medicinal potential of the ethanol extract of Micromeria graeca (L.) Benth. ex Rchb. harvested in Algeria (MG extract), was evaluated by assessing in vitro its antioxidant, antibacterial, and antityrosinase properties. The total phenolic (= 430 ± 30 mg gallic acid equivalent/100 g of dry weight) and flavonoid (= 190 ± 10 mg quercetin equivalent/100 g of dry weight) contents were evaluated by the Folin–Ciocalteu and the aluminium chloride methods, respectively. Silica gel thin-layer chromatography revealed the presence of chlorogenic, caffeic, and rosmarinic acids and diosmin; the presence of these compounds was confirmed by reverse phase high-performance liquid chromatography. The IC50 values indicate that the ethanol extract of M. graeca is highly potent in neutralizing the 2,2ʹ-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) cation radicals (ABTS•+; IC50 = 30.5 ± 0.9 µg/mL) and the 2,2ʹ-diphenyl-1-picrylhydrazyl radicals (DPPH•; IC50 = 65.8 ± 2.4 µg/mL). The MG extract was also very active on a lipid peroxidation model (IC50 = 23.4 ± 1.9 µg/mL). The superoxide quenching index values (electrochemically measured) were 332 ± 37 (AI30) and 638 ± 53 µg/mL (AI50). The studied extract showed a moderate tyrosinase inhibitory activity (IC50 =302 ± 62 µg/mL) and a low antibacterial effect while the combination of this extract with antibiotics restored the activities of cefotaxime and streptomycin on resistant Staphylococcus aureus and Pseudomonas aeruginosa., SCOPUS: ar.j, info:eu-repo/semantics/published

The control and treatment of food crops bacterial diseases remain problematic due to a scarcity of effective phytotreatments. As traditional agricultural practices may represent an attractive venue to explore new treatments, Malagasy traditional practices were investigated for their effectiveness on potato plants. A survey was conducted among Malagasy farmers to collect information on diseases observed on potato crops and on traditional disease control practices. Twelve treatments against potato bacterial diseases were tested on two potato varieties, in experimental plots naturally infected by bacterial wilt disease. The information collected from 52 farmers (i) showed that leaf spots and bacterial wilt disease are the most frequently identified threats for potato crops; and (ii) allowed to identify 12 traditional treatments among which five exhibited protective properties on potato bacterial wilt disease. Moreover, one recipe (R07) was effective on the two potato varieties after two applications per week for 10 weeks, with 50% and 72% effectiveness rate, respectively. Valorization of traditional practices may provide an effective, safe, economic and standardized phytotreatment against potato bacterial wilt disease., SCOPUS: ar.j, info:eu-repo/semantics/inPress

Background: To achieve effective antiretroviral therapy (ART) outcomes, adherence to an antiretroviral regimen and a good immunometabolic response are essential. Food insecurity can act as a real barrier to adherence to both of these factors. Many people living with human immunodeficiency virus (PLHIV) treated with ART in the Democratic Republic of the Congo (DRC) are faced with nutritional challenges. A significant proportion are affected by under nutrition, which frequently leads to therapeutic failure. Some HIV care facilities recommend supplementation with Moringa oleifera (M.O.) Lam. leaf powder to combat marginal and major nutritional deficiencies. This study aims to assess the impact of M.O. Lam. leaf powder supplementation compared to nutritional counseling on the nutritional and immune status of PLHIV treated with ART. Methods: A single-blind randomized control trial was carried out from May to September 2013 at an outpatient clinic for HIV-infected patients in Kinshasa (DRC). Sixty adult patients who were at stable HIV/AIDS clinical staging 2, 3 or 4 according to the World Health Organization (WHO), and were undergoing ART were recruited. After random allocation, 30 patients in the Moringa intervention group (MG) received the M.O. Lam. leaf powder daily over 6 months, and 30 in the control group (CG) received nutritional counseling over the same period. Changes in the body mass index (BMI) were measured monthly and biological parameters were measured upon admission and at the end of the study for the patients in both groups. Results: The two study groups were similar in terms of long-term nutritional exposure, sociodemographic, socioeconomic, clinical, and biological features. At 6 months follow-up, patients in the MG exhibited a significantly greater increase in BMI and albumin levels than those in the CG. The interaction between the sociodemographic, clinical, and biological characteristics of patients in the two groups was not significant, with the exce, SCOPUS: ar.j, info:eu-repo/semantics/published

Objective To investigate the chemical composition of a moderately polar extract (CHCl3 soluble part of the MeOH–H2O extract) obtained from the aerial parts (leaves and flowers) of Centaurea diluta Ait. subsp. algeriensis (Coss. & Dur.) Maire, a species endemic to Algeria and Morocco on which no reports are available to date. To evaluate in vitro the cytotoxic, antifungal and antimicrobial activities of this extract and the cytotoxic and antimicrobial activities of its isolated secondary metabolites. Methods The cytotoxic effects of the extract were investigated on 3 human cancer cell lines i.e. the A549 non-small-cell lung carcinoma (NSCLC), the MCF7 breast adenocarcinoma and the U373 glioblastoma using a MTT colorimetric assay. Biological data allowed to guide the fractionation of the extract by separation and purification on silica gel 60 (CC and TLC). The isolated compounds which were characterized by spectral analysis, mainly HR-ESIMS, HR-EIMS, UV and NMR experiments (1H, 13C, COSY, ROESY, HSQC and HMBC) and comparison of their spectroscopic data with those reported in the literature, were evaluated for cytotoxic activities on six cancer cell lines (A549, MCF7, U373, Hs683 human glioma, PC3 human prostate and B16-F10 murine melanoma). The direct and indirect antibacterial and antifungal activities were determined using microdilution methods for the raw extract and TLC-bioautography and microdilution methods against standard and clinical strains for the isolated compounds. Results The raw extract reduced cell viability with IC50s of 27, 25 and 21 μg/mL on A549, MCF7 and U373, respectively. Five secondary metabolites: two phenolic compounds (vanillin 1, paridol 3), a lignan [(−)-arctigenin 2] and two flavonoid aglycones (eupatilin 4 and jaceosidin 5), were then isolated from this extract. Moderate cytotoxic effects were observed for (−)-arctigenin 2 (IC50s: 28 and 33 μM on Hs683 and B16-F10, respectively), eupatilin 4 (IC50s: 33 and 47 μM on B16-F10 and PC3, respe, SCOPUS: ar.j, info:eu-repo/semantics/published

Despite efforts in recent years, infectious diseases remain a worldwide major public health problem. Several infectious agents have become resistant to conventional antibiotics and there is thus urgent need to discover new antimicrobial drugs to overcome resistances. Platostoma rotundifolium (Briq.) A. J. Paton, an African plant, is mainly used to treat microbial infections in traditional Burundian medicine. From the ethyl acetate extract of the aerial parts, five pentacyclic triterpenoid acids were isolated and characterized. Based on spectral analysis, these compounds were elucidated to be 2α, 3α, 19β-trihydroxyurs-12-en-28-oic acid (that was named jeremic acid) (1), 3β-hydroxyurs-12-en-28-oic acid (ursolic acid) (2), 2α, 3β-dihydroxyurs-12-en-28-oic acid (corosolic acid) (3), 2α, 3β, 19α-trihydroxyurs-2-en-28-oic acid (tormentic acid) (4) and 19-hydroxy-2-hydroxymethyl norursa-2, 12-dien-28-oic acid (hyptadienic acid) (5). Ursolic (MIC = 17.5-68 μM) and corosolic (MIC = 17-68 μM) acids showed significant antibacterial activities against both the Gram-positive Staphylococcus aureus (methicillin-susceptible and -resistant strains) and the Gram-negative Escherichia coli, which may substantiate the use of P. rotundifolium in traditional Burundian medicine. Such hydroxylated pentacyclic triterpenoid acids could point to new antimicrobial strategies that may help overcoming the antimicrobial resistances actually observed throughout the world., SCOPUS: ar.j, info:eu-repo/semantics/published

Background: The use of skin-lightening (SL) cosmetics appears to be common throughout the world, especially among dark-skinned women from sub-Saharan Africa. Objectives: The aims of this study were to evaluate the extent of the practice of SL in Kigali, the capital city of Rwanda, the motivations behind this practice and the complexity of the adverse effects observed. Methods: An inventory of products sold on the Kigali market and their contents were compared with the results of a survey investigating the products used by the local population in order to deduce the proportions of people who depigment. The prevalence and severity of SL side effects (dermatitis, skin cancers, etc.) were evaluated in collaboration with dermatologists and general practitioners through a specific questionnaire and interviews. The sociological profiles of adolescents and their motivations for practicing SL were studied using qualitative and descriptive approaches through semi-direct individual and collective interviews. Results: A total of 27 creams were identified and classified according to labeled ingredients known to be depigmenting agents; 35% of the surveyed population were found to use products with skin-bleaching properties, but only 27% stated that they used the products specifically for these depigmenting properties. An inquiry into the motivations of adolescents indicated that they know about and practice SL but are restricted by family, religion, and Rwandese culture. Whenever side effects appear, consumers opt either to stop bleaching practices for a short period or to switch from their commercial topical product to another one with, presumably, a different composition. Conclusions: Albeit that many people acknowledge that there are possible side effects of using preparations commonly used in SL, the practice is generally continued. Although it is important to question the rationale behind the practice of SL, it is equally important to develop and propose safer products., SCOPUS: ar.j, FLWIN, info:eu-repo/semantics/published

Background: The use of skin-lightening (SL) cosmetics appears to be common throughout the world, especially among dark-skinned women from sub-Saharan Africa. Objectives: The aims of this study were to evaluate the extent of the practice of SL in Kigali, the capital city of Rwanda, the motivations behind this practice and the complexity of the adverse effects observed. Methods: An inventory of products sold on the Kigali market and their contents were compared with the results of a survey investigating the products used by the local population in order to deduce the proportions of people who depigment. The prevalence and severity of SL side effects (dermatitis, skin cancers, etc.) were evaluated in collaboration with dermatologists and general practitioners through a specific questionnaire and interviews. The sociological profiles of adolescents and their motivations for practicing SL were studied using qualitative and descriptive approaches through semi-direct individual and collective interviews. Results: A total of 27 creams were identified and classified according to labeled ingredients known to be depigmenting agents; 35% of the surveyed population were found to use products with skin-bleaching properties, but only 27% stated that they used the products specifically for these depigmenting properties. An inquiry into the motivations of adolescents indicated that they know about and practice SL but are restricted by family, religion, and Rwandese culture. Whenever side effects appear, consumers opt either to stop bleaching practices for a short period or to switch from their commercial topical product to another one with, presumably, a different composition. Conclusions: Albeit that many people acknowledge that there are possible side effects of using preparations commonly used in SL, the practice is generally continued. Although it is important to question the rationale behind the practice of SL, it is equally important to develop and propose safer products., SCOPUS: ar.j, FLWIN, info:eu-repo/semantics/published

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Description of the subject. Several ethnobotanical studies have demonstrated links between traditional medicine practices and the ethnicity and geographical location of healers, while many others have concluded the opposite. This study deals with the typology of traditional healers in the mountain region of Kahuzi-Biega. Objectives. The goal is to understand whether the typology of traditional healers is related to their inter-ethnic and inter-zonal differences, based on diseases treated and plants used. Method. Ethnobotanical surveys were conducted using the “PSSVV” method. This involved 88 traditional healers recognized as “specialists” in 33 villages adjacent to the forest of Kahuzi-Biega, in DR Congo. Multivariate analysis (clustering, ordination, Mantel test, IndVal) were applied to establish typologies of traditional healers. Results. Multivariate analyses showed that ethnicity and geographical location did not explain the practices and knowledge of healers. However, by using the IndVal method, differences were observed in their degree of specialization. Non-specialized healers (70%) could be distinguished from specialized healers (30%). Two clear groups of specialists emerged; those who treat bone trauma and those who treat obstetric-gynecological complaints. The Mantel correlation test revealed a positive association (r = 0.134, p < 0.05) between the “healers-plants” and “healers-diseases” matrices. This indicates that healers who treat similar diseases use similar herbs. Both typologies have shown their preferences for forest species (81%), especially trees (51%). Conclusions. This exploratory study suggests that traditional healers are characterized based on their specializations. This result helps in creating strategies to preserve local traditional knowledge and apply it to the conservation of species., SCOPUS: ar.j, info:eu-repo/semantics/published

Les pathologies infectieuses, maladies causées par certains micro-organismes pathogènes parmi les bactéries, les virus, les champignons et les protozoaires, sont à l’origine des taux de mortalité et de morbidité élevés enregistrés surtout dans les pays en voie de développement où la majorité de la population n’a pas les moyens d'accéder aux soins de santé. Les résistances des micro-organismes aux antimicrobiens, observées actuellement dans la pratique médicale moderne, constituent un autre grand problème lié au traitement de ces maladies. Elles constituent l’une des menaces de santé les plus sérieuses et peuvent frapper n’importe qui dans le monde. Face à ces fléaux, il est urgent de découvrir de nouveaux agents antimicrobiens qui pourraient, éventuellement, présenter de nouveaux mécanismes d'action. Une bonne part des plantes utilisées en médecines traditionnelles contiennent des composants antimicrobiens utiles contre les infections et qui peuvent aider dans la lutte contre les maladies infectieuses liées à l’antibiorésistance. C’est dans cette optique que nous avons mené une enquête ethnobotanique sur les plantes médicinales utilisées contre les infections microbiennes en médecine traditionnelle Burundaise. Nous en avons inventorié 155 et sélectionné 5 d'entre elles (Justicia subsessilis Oliv. (Acanthaceae); Platostoma rotundifolium (Briq.) A. J. Paton (Lamiaceae), Virectaria major (Schum.) Verdc. (Rubiaceae), Pavetta ternifolia (Oliv.) Hiern (Rubiaceae), et Stomatanthes africanus (Oliv. & Hiern) R. M. King & H. Rob. (Asteraceae)) pour en étudier la composition phytochimique et les propriétés biologiques. Les extraits de ces plantes ont été évalués notamment pour leurs effets antibactériens direct (bactéricide ou bactériostatique) et indirect (modulation des mécanismes de résistance qui augmente ou restaure l’activité des antibiotiques sur des souches résistantes). Les cinq plantes retenues ont montré une activité antibactérienne, justifiant ainsi leur usage cont, Infectious pathologies are diseases caused by the transmission of some pathogenic microorganisms among bacteria, viruses, fungi and protozoa. They drive the high mortality and morbidity rates recorded especially in developing countries, where the majority of the population cannot afford to access health care. The antimicrobial resistances currently observed in modern medical practice represent another major problem in the treatment of these diseases. These resistances are one of the most serious population health threats and can strike anyone in the world. It has thus become urgent to discover new antimicrobial agents that could possibly have novel mechanisms of action.Many plants used in traditional medicines against infections harbor useful antimicrobial components that can help in the fight against infectious diseases and antibiotic resistances. In this context, we conducted an ethnobotanical survey of medicinal plants used in Burundian traditional medicine to treat microbial infections. We inventoried 155 herbs from which 5 (Justicia subsessilis Oliv. (Acanthaceae); Platostoma rotundifolium (Briq.) A. J. Paton (Lamiaceae), Virectaria major (Schum.) Verdc. (Rubiaceae), Pavetta ternifolia (Oliv.) Hiern (Rubiaceae), and Stomatanthes africanus (Oliv. & Hiern) R. M. King & H. Rob. (Asteraceae) were selected for phytochemical screening and biological assays. The extracts of these plants were evaluated for their antibacterial effects, direct (bacteriostatic or bactericidal) and indirect (inhibition of resistance mechanisms by increasing or restoring the activity of antibiotics against resistant strains). All the selected plants species have shown antibacterial activity, justifying their use against microbial infections in Burundian traditional medicine, and more particularly Platostoma rotundifolium, whose extracts showed direct and indirect antibacterial effects on susceptible and resistant (MRSA) strains. The extracts from Platostoma rotundifolium also presented inhi, Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie), info:eu-repo/semantics/nonPublished

De nombreuses études épidémiologiques et cliniques ont montré que la pollution aux particules en suspension était étroitement liée à la morbidité et à la mortalité cardiovasculaire. Les particules les plus fines, d’un diamètre aérodynamique inférieur à 2,5 µm, semblent être les plus nocives car elles peuvent pénétrer profondément dans les poumons et pourraient atteindre la circulation systémique. Une grande partie de cette fraction est constituée de particules diesel (DEP) issues du trafic automobile. Cependant, les mécanismes physiopathologiques responsables de la toxicité des particules diesel n’ont pas encore été entièrement identifiés.Afin de mieux comprendre le mode d’action des DEP, nous avons étudié dans un premier temps leurs effets sur la fonction endothéliale vasculaire. Nous avons d’abord évalué leurs effets in vitro sur les réponses vasomotrices d’aorte isolée de rat. Nous avons observé que l’incubation avec les DEP inhibait les relaxations endothélium-dépendantes à l’acétylcholine, à la fois chez le rat normo- et chez le rat hypertendu ;cet effet est réversible après ajout de superoxyde dismutase. Les réponses endothélium-indépendantes sont également altérées mais dans une moindre mesure. Ces résultats montrent que la toxicité vasculaire des DEP est due à un stress oxydatif. Nous avons ensuite analysé les effets in vivo (par voie endotrachéale) de ces DEP. Les résultats ont montré que les DEP induisaient une inhibition des réponses endothélium-dépendantes, mais uniquement chez le rat hypertendu. Il semblerait donc que, in vivo, il y ait une synergie d’action entre les DEP et l’hypertension. Cette dysfonction endothéliale est accompagnée d’une surexpression de l’ARNm de la p22phox, sous-unité de la NADPH oxydase connue pour son implication majeure dans le stress oxydatif de la paroi vasculaire.La seconde partie de notre travail a consisté à identifier des substances médicamenteuses capables de prévenir les désordres occasionnés par les DEP. Nous avons ai, Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie), info:eu-repo/semantics/nonPublished

RésuméLe présent travail a été réalisé dans et autour de la forêt de montagne du Parc National de Kahuzi-Biega (PNKB), à l’Est de la RD Congo. Ce site naturel de patrimoine mondial fut créé principalement pour protéger la sous-espèce de gorille, le Gorilla beringei graueri, une espèce en danger critique d’extinction. L’objectif de cette thèse est d’analyser le double usage des espèces végétales qui sont utilisées dans la médecine traditionnelle et dans le régime alimentaire des gorilles pour une gestion durable de la biodiversité, et en particulier, des ces espèces végétales les plus sollicitées par les tradipraticiens et qui sont utiles dans l’alimentation et potentiellement l’automédication des gorilles. Pour réaliser cette étude, nous avons abordé les tradipraticiens spécialistes ;nous avons fait des observations directes de gorilles de 4 groupes et nous avons évalué la végétation de leur habitat en forêt d’altitude du parc. L’analyse des données a été réalisée grâce aux approches de l’ethnobotanique quantitative et de l’écologie numérique.Les résultats montrent que, sur la base de l’usage de 77 espèces médicinales inventoriées, la typologie des tradipraticiens n’est pas basée sur leurs origines ethniques et géographiques mais sur leurs spécialités. Ils utilisent les mêmes plantes pour soigner les mêmes maladies. La forte convergence de leurs pratiques et le degré de consensus très élevé sur les plantes qu’ils utilisent pour traiter les maladies traduisent une tradition médicinale solidement ancrée au sein des groupes ethniques vivant dans cette région du Parc. Cependant, 83% des espèces utilisées par les tradipraticiens sont forestières. Les usages des plantes médicinales comparés aux choix alimentaires des gorilles montrent que 78 % des espèces végétales consommées par ces primates sont utilisées par les tradipraticiens, avec une similarité de 80% d’usage des parties de plantes. Ce chevauchement très élevé d’usages traduit une compétition potentielle pour les p, Doctorat en Sciences agronomiques et ingénierie biologique, info:eu-repo/semantics/nonPublished

Various extracts from the seeds of Nigella sativa have been used in traditional folk medicine to treat inflammation, liver disorders and arthritis. These seeds have been experimentally shown to possess antioxidant and hepatoprotective properties. Beside the hypoglycaemic and hypolipidemic effects, this study was carried out to evaluate, in vitro, toxicological effect of lipid extracts from the Nigella sativa seeds. The tested fractions were: (i) defatted methanolic extract, (ii) total lipid extract obtained by hexane extraction from methanolic extract and (iii) neutral and polar lipid fractions. The fractions were assessed, in vitro, for their inhibitory activity potential on the enzyme alphaglucosidase as suppressing the enzyme activity is one among the therapeutic approaches to attenuate postprandial hyperglycemia. High inhibition of alpha-glucosidase by the two polar lipid fractions (F6 and F7) was reflected by their IC50 (0.51±0.04mg/ml and 0.55±0.09mg/ml, respectively), compared to acarbose (0.53±0.06mg/ml) and thymoquinone (0.65±0.05mg/ml). The hypoglycaemic effect of the polar lipid fraction of Nigella sativa could be explained by the inhibition of alpha-glucosidase, which is one of early steps of carbohydrate metabolism. Toxicological evaluation was investigated on precision-cut rat liver slices (PCLS). On PCLS, lipid extracts reduced ATP levels by 27 to 35%. Results indicate suggest that Nigella sativa extracts don't show a hepatoprotective effect against acetaminophen, but don't exhibit a major hepatotoxicity when tested alone., SCOPUS: ar.j, info:eu-repo/semantics/published

Essential tremor (ET) is one of the most prevalent neurological disorders in the world. Environmental factors have been implicated in the pathogenesis of ET. In particular, epidemiological studies have suggested that neurotoxic agents, especially β-carboline alkaloids (βCAs), might be generated through Maillard-type reaction. βCAs are molecules which are members of a large group of heterocyclic amines (HCAs, the so-called products of cooking meat). βCAs are highly tremorogenic in animals, producing a marked generalized action tremor soon after systemic administration in a wide range of laboratory animals such as mice, rats and monkeys. Administration of βCAs remains currently the main experimental model of ET. We review the pathogenesis of ET, with a focus on the biochemistry of βCAs, their occurrence and biological activity, their endogenous biosynthesis, their formation in food, their toxicokinetics and their neurotoxicity. We highlight open questions regarding the effects of βCAs in humans., SCOPUS: re.j, info:eu-repo/semantics/published

This in vitro study aimed to determine the effects of a Panax ginseng extract on aristolochic acid-mediated toxicity in HK-2 cells. A methanolic extract of ginseng (50 μg/mL) was able to reduce cell survival after treatment with 50 μM aristolochic acid for 24, 48, and 72 h, as evidenced by a resazurin reduction assay. This result was confirmed by a flow cytometric evaluation of apoptosis using annexin V-PI staining, and indicated higher apoptosis rates in cells treated with aristolochic acid and P. ginseng extract compared with aristolochic acid alone. However, P. ginseng extract by itself (5 and 50 μg/mL) increased the Ki-67 index, indicating an enhancement in cellular proliferation. Cell cycle analysis excluded a P. ginseng extract-mediated induction of G2/M cell cycle arrest such as the one typically observed with aristolochic acid. Finally, β-catenin acquisition was found to be accelerated when cells were treated with both doses of ginseng, suggesting that the epithelial phenotype of renal proximal tubular epithelial cells was maintained. Also, ginseng treatment (5 and 50 μg/mL) reduced the oxidative stress activity induced by aristolochic acid after 24 and 48 h. These results indicate that the ginseng extract has a protective activity towards the generation of cytotoxic reactive oxygen species induced by aristolochic acid. However, the ginseng-mediated alleviation of oxidative stress did not correlate with a decrease but rather with an increase in aristolochic acid-induced apoptosis and death. This deleterious herb-herb interaction could worsen aristolochic acid tubulotoxicity and reinforce the severity and duration of the injury. Nevertheless, increased cellular proliferation and migration, along with the improvement in the epithelial phenotype maintenance, indicate that ginseng could be useful for improving tubular regeneration and the recovery following drug-induced kidney injury. Such dual activities of ginseng certainly warrant further in vivo studies., SCOPUS: ar.j, info:eu-repo/semantics/published

Acute kidney injury (AKI) is often encountered in patients receiving cisplatin (CisPt), a chemotherapeutic drug that induces numerous toxic side effects. Techniques used to limit nephrotoxicity during CisPt treatment are not fully effective; about a third of patients experience AKI. New nephroprotective strategies, including pharmacological approaches, must be developed., SCOPUS: ar.j, info:eu-repo/semantics/published

Acute kidney injury (AKI) is a major health threat worldwide. The literature on herbal intervention in AKI was searched from English and Chinese databases and reports were critically analyzed in terms of preventing AKI, promoting repair and regeneration, enhancing extrarenal clearance of uremic toxins, and preventing progression to chronic kidney disease (CKD). Altogether, 16 herbal formulae and a few extracts derived from individual herbs were reported to prevent or mitigate AKI in animal models induced by renal ischemia/reperfusion, cisplastin, gentamicin, glycerol, adenine, sepsis or physical exhaustion. Four formulae and six individual herbs were reported to accelerate recovery and/ or to prevent CKD in established AKI animal models. Intrarectal herbal medicines, with or without simultaneous oral administration, were reported in six clinical trials and in an animal model to increase extrarenal clearance of uremic toxins. Additional 13 clinical trials reported oral or intravenous herbal interventions in AKI of different etiologies. Despite recurring problems, notably poor compliance with good practice guidelines for clinical trials and for authentication, naming and quality control of herbal materials, accumulating experimental data on the preventive effects of herbal medicines in AKI look encouraging and urge for better, definitive trials to guide clinical practice. Herbal enemas promoting extrarenal clearance of uremic toxins seem cost-effective, but better clinical evidence is certainly needed before any affirmative recommendation be made for AKI patients without access to dialysis. New frontiers, however, lie in those herbal remedies that promote repair/ regeneration and prevent chronicity after AKI. Recent experimental data suggest that this may be possible. Abbreviations: AKI: acute kidney injury; AKIN: Acute Kidney Injury Network; αSMA: α smooth muscle actin; ARF: acute renal failure; ATN: acute tubular necrosis; BUN: blood urea nitrogen; CAT: catalase; CK, SCOPUS: ar.j, info:eu-repo/semantics/published

Ethnopharmacological relevance: Infectious diseases represent a serious and worldwide public health problem. They lead to high mortality, especially in non-developed countries. In Burundi, the most frequent infectious diseases are skin and respiratory (mainly in children) infections, diarrhea, added to malaria, HIV/AIDS and tuberculosis. Local population used mostly traditional herbal medicines, sometimes animal and mineral substances, to fight against these plagues. Objectives: To survey in different markets and herbal shops in Bujumbura city, medicinal plants sold to treat microbial infections, with particular emphasis on the different practices of traditional healers (THs) regarding plant parts used, methods of preparation and administration, dosage and treatment duration. Materials and methods: The ethnobotanical survey was conducted by interviewing, using a pre-set questionnaire, sixty representative healers, belonging to different associations of THs approved and recognised by the Ministry of Health. Each interviewed herbalist also participated in the collection of samples and the determination of the common names of plants. The plausibility of recorded uses has been verified through an extensive literature search. Results: Our informants enabled us to collect 155 different plant species, distributed in 51 families and 139 genera. The most represented families were Asteraceae (20 genera and 25 species), Fabaceae (14 genera and 16 species), Lamiaceae (12 genera and 15 species), Rubiaceae (9 genera and 9 species), Solanaceae (6 genera and 6 species) and Euphorbiaceae (5 genera and 6 families). These plants have been cited to treat 25 different alleged symptoms of microbial diseases through 271 multi-herbal recipes (MUHRs) and 60 mono-herbal recipes (MOHRs). Platostoma rotundifolium (Briq.) A. J. Paton (Lamiaceae), the most cited species, has been reported in the composition of 41 MUHRs, followed by Virectaria major (Schum.) Verdc (Rubiaceae, 39 recipes), Kalanch, SCOPUS: ar.j, info:eu-repo/semantics/published