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Les plantes medicinales telles que Moringa oleifera, presentent en general de nombreuses vertus therapeutiques. L’objectif de cette etude etait d’evaluer l’activite antioxydante des extraits des feuilles de Moringa oleifera par la methode de piegeage des radicaux libres 2,2-diphenyl-1- picryl-hydrazyle (DPPH•). Une extraction ethanolique a ete effectuee et l’extrait sec obtenu a ensuite ete fractionne par la methode de separation liquide-liquide avec des solvants polaires (eau distillee et acetate d’ethyle) et apolaires (dichloromethane). L’extrait ethanolique, ses fractions et l’acide L-ascorbique (antioxydant de reference), ont ete testes a differentes concentrations: 12,5; 25; 50; 100 et 200 μg/ml. La lecture de l’absorbance des produits s’est faite au bout de 30 minutes au spectrophotometre a 517 nm. Il ressort de cette etude que l’extrait ethanolique des feuilles de Moringa oleifera et ses differentes fractions possedent une activite antioxydante significative qui est dose-dependante.Cependant, l’activite la plus importante a ete observee avec l’extrait ethanolique avec une concentration inhibitrice 50 (CI50) de 87,86±1,80 μg/ml. Les resultats de cette etude suggerent que les feuilles de Moringa oleifera contiennent des substances a proprietes antioxydantes qui pourraient contribuer a la prevention de certaines maladies chroniques telles que le cancer, les maladies cardiovasculaires entre autres. © 2018 International Formulae Group. All rights reserved. Mots cles: Moringa oleifera , activite antioxydante, fractionnement, DPPH English Title: Evaluation of the antioxidant activity of leaves of Moringa oleifera Lam. (Moringaceae) of Senegal English Abstract Medicinal plants such as Moringa oleifera generally have several therapeutic virtues. This study aimed to evaluate the antioxidant activity of Moringa oleifera leaves extracts using the free radical scavenging method: 2,2-diphenyl-1-picryl-hydrazyl (DPPH•) assay. Ethanolic extraction was carried out and the dry extract obtained was then fractionated by the liquid-liquid separation method with polar solvents (distilled water and ethyl acetate) and non polar solvent (dichloromethane). The antioxidant activities of the ethanolic extract, its fractions and the Lascorbic acid (reference antioxidant) were tested at various concentrations of 12.5; 25; 50; 100 and 200 μg/ml. The absorbance of the products was read after 30 minutes at the spectrophotometer at 517 nm. It emerged from this study that the ethanolic extract of Moringa oleifera leaves and its different fractions had significant antioxidant activity that is dose-dependent. However, the ethanolic extract was more active on DPPH radical inhibition with a concentration of sample required to scavenge 50% of free radicals (CI50) of 87.86 ± 1.80 μg/ml. These results suggest that leaves of Moringa oleifera contain substances with antioxidant properties that could contribute to the prevention of chronic diseases such as cancer, cardiovascular diseases, among others. © 2018 International Formulae Group. All rights reserved. Keywords: Moringa oleifera , antioxidant activity, DPPH

The authors present a summary of the proceedings and the recommendations of the Fourth International Conference on Envenomations by Snakebites and Scorpion Stings in Africa, held from 25 to 29 April 2011 in Dakar. After a two-day workshop for Senegalese health personnel on the most relevant aspects of the management of envenomations, about 270 participants met to share their experiences in the field. Nearly a hundred oral and poster presentations were made on the epidemiology of snakebites and scorpion stings in Africa, the composition and action of venoms and the manufacture and use of antivenoms. The last day was devoted to an institutional debate involving experts, representatives of national health authorities and concerned professionals (physicians, pharmacists, nurses and traditional healers) as well as members of the pharmaceutical industry to discuss and elaborate a set of recommendations. It was agreed that it is necessary to improve knowledge of the epidemiological situation by case reporting. Quality control of antivenoms and procedures for their registration at the level of national health authorities should aim at improving the distribution of safe and effective antivenoms in peripheral health centers for the better assessment of victims. It was also recommended that adequate training should be provided for health personnel in all aspects of medical management of envenomations. Equitable distribution of funding and the establishment of a network of African experts were also discussed in the conference.

Diabetes is the most common metabolic disorder worldwide and is a major public health problem. Its frequency increases every day in all countries. However, in developing African countries, few people have access to drugs. In addition, in Africa, traditional beliefs induce people to use medicinal plants whenever they have health problems. Thus, many people in these developing countries use plants for the treatment of diabetes. Yet, few studies are focused on the knowledge and attitudes of the users on medicinal plants in Africa in general and in Senegal in particular. Hence we undertook this survey on the use of medicinal plants for the treatment of diabetes in Senegal in order to make recommendations which could contribute to the increase of the value of herbal medicines in developing countries. We did a cross-sectional survey by direct interview at a university teaching hospital, in Dakar with a representative sample of 220 patients. Forty-one plants were used by the patients and the two most frequently cited were Moringa oleifera Lam (65.90%) and Sclerocarya birrea (A. Rich) Hochst (43.20%). Patients gave several reasons for using medicinal plants (traditional treatment: 40%, efficacy: 32%, low cost: 20%). The principal suppliers of plants were tradesmen in the market (66.8%) and traditional therapists (5%). Sixty-five per cent of patients think that medicinal plants are efficient for the treatment of diabetes and 20% have reported adverse effects which could be caused by medicinal plants. In conclusion, many people in our study think that medicinal plants are efficient for the treatment of diabetes, which requires research work by scientists in developing countries in this field in order to prove their efficacy and innocuousness.

Benzodiazepines are relatively well-tolerated medicines but can induce serious problems of addiction and that is why their use is regulated. However, in developing countries like Senegal, these products are used without clear indications on their prescription, their dispensation or their use. This work focuses on the prescription of these medicines with a view to make recommendations for their rational use. Benzodiazepine prescription was studied with psychiatrists or neurologists and generalists in 2003. Specialist doctors work in two Dakar university hospitals and generalists in the 11 health centres in Dakar. We did a survey by direct interview with 29 of 35 specialists and 23 of 25 generalists. All doctors were interviewed in their office. The questionnaire focused on benzodiazepine indications, their pharmacological properties, benzodiazepines prescribed in first intention against a given disease and the level of training in benzodiazepines by doctors. Comparisons between specialists and generalists were made by chi-square test. Benzodiazepines were essentially used for anxiety, insomnia and epilepsy. With these diseases, the most benzodiazepines prescribed are prazepam against anxiety and insomnia and diazepam against epilepsy. About 10% of doctors do not know that there is a limitation for the period of benzodiazepine use. The principal reasons of drugs choice are knowledge of the drugs, habit and low side effects of drugs. All generalists (100%) said that their training on benzodiazepines is poor vs. 62.1% of specialists, and doctors suggest seminars, journals adhesions and conferences to complete their training in this field. There are not many differences between specialists and generalists except the fact that specialists prefer prazepam in first intention in the insomnia treatment where generalists choose bromazepam. In addition, our survey showed that specialists' training in benzodiazepines is better than that of generalists. Overall, benzodiazepine prescription poses problems particularly in training, and national authorities must take urgent measures for rational use of these drugs.

Mitragyna inermis is used in the Senegal traditional medicine for treating stomach and intestinal disorders. At concentrations of 0.5, 0.75 and 1 mg/ml, the aqueous extract of M. inermis bark (AEMIB) significantly induced a decrease of the ileal basal tonus, respectively, from 37+/-1, 51+/-1 and 75+/-2% (P0.05; n=5), compared to the baseline values. As well as atropine, AEMIB inhibited submaximal contractions induced by 0.01 mg/ml ACh with IC(50) value of approximately 0.75 mg/ml (n=5). These results show that AEMIB possesses both myorelaxant and antispasmodic actions in the ileum. This may justify the pharmacological basis for the popular use of Mitragyna for the treatment of gastrointestinal disorders.

Prescription and use of benzodiazepins were evaluated with a patients survey. Direct interview were conducted with 150 patients in ten pharmacies in the city of Saint-Louis, Senegal from January to June 2002. Ten of the 15 retail pharmacies in this city agreed to participate in the survey. All patients gave their agreement to participate to the study; the questionnaire contained essentially closed questions. Writers of prescriptions were general practitioners (38.67%), specialists (34.67%), nurses (18%) and midwifes (8.66%). The most prescribed benzodiazepins were prazepam, dipotassic clorazepate, lorazepam and diazepam. Use of these drugs during night is most recommended. Nevertheless, 26.67% of the prescriptions indicated the drug should be use during the day. The period of use was between one and three Months for 33.99% of patients and three Months or more in 42%. Benzodiazepins were used by 66.67% for insomnia, alone or associated with another condition, for anxiety by 14.6% and for epilepsy by 10%. Prescriptions were for benzodiazepins alone in 47.37% of the patients and in combination with other psychotropic drugs for 19.33%. Somnolence and dependence were the most reported side effects.

Moringa oleifera est une plante de la pharmacopee africaine, tres utilisee en medecine traditionnelle pour ses nombreuses applications therapeutiques. L’objectif de la presente etude etait de fractionner la fraction methanolique de l’extrait hydro-alcoolique de ses feuilles dont les proprietes anti-inflammatoires avaient ete demontrees anterieurement et d’identifier la sous-fraction methanolique la plus active. La methode de separation liquide-liquide a ete utilisee pour partitionner la fraction methanolique. Trois sous-fractions methanoliques (F1, F2 et F3) sont obtenues a l’issue du fractionnement. L’activite anti-inflammatoire de ces extraits a ete testee sur un modele pharmacologique d’oedeme aigu de la patte de rat induit par la carraghenine en comparaison a celle de l’aspirine utilisee comme substance de reference. Apres administration par gavage, l’aspirine (30 mg/kg) et les extraits (15 et 30 mg/kg) previennent de maniere significative, l’oedeme de la patte des rats de la 1 ere a la 5 eme heure de l’experience. L’etude montre globalement une activite anti-inflammatoire des sous-fractions F1, F2 et F3. L’effet le plus important est observe avec la F3 durant les trois 1eres heures de l’experience avec une cinetique d’inhibition de l’oedeme comparable a celle de l’aspirine. Ces resultats suggerent que les feuilles de Moringa oleifera pourraient constituer une source potentielle d’antiinflammatoires dans le traitement des pathologies ayant une composante inflammatoire. © 2016 International Formulae Group. All rights reserved. Mots cles: Moringa oleifera , feuilles, anti-inflammatoire, sous-fractions methanoliques English Title: Study of the anti-inflammatory activity of methanolic sub-fractions of the leaves of Moringa Oleifera Lam. (Moringaceae) in rat English Abstract Moringa oleifera is an African pharmacopoeia plant, widely used in traditional medicine for its many therapeutic applications. This study aimed at partitioning the methanolic fraction of hydro-alcoholic leaves extract of which anti-inflammatory properties have been previously demonstrated and to identify the most active methanolic sub-fraction. The liquid/liquid fractionation method was used to partition the methanolic fraction. Three methanolic sub-fractions (F1, F2 and F3) were obtained from the fractionation. Antiinflammatory activity of extracts was tested using pharmacological model of carrageenan-induced acute paw oedema in rats compared to that of aspirin (reference). After oral administration, aspirin (30 mg/kg) and extracts (15 and 30 mg/kg) significantly prevented carrageenan-induced paw oedema in rats from the 1 st to 5 th hours of experimentation. Study showed overall anti-inflammatory activity of methanolic sub-fractions. The most important effect was observed with the F3 during the first three hours with a kinetic inhibition of oedema similar to that of aspirin. These results suggest that the leaves of Moringa oleifera could be a potential source of anti-inflammatory drugs in treatment of diseases with an inflammatory component. © 2016 International Formulae Group. All rights reserved. Keywords: Moringa oleifera , leaves, anti-inflammatory, methanolic sub-fractions

This study was undertaken to investigate the vasodilatory effect of an aqueous extract of Elaeis guineensis Jacq (EGE) in the porcine coronary artery and elicit its possible mechanism(s) of action. Vascular effects of crude extract of dried and powdered leaves of Elaeis guineensis were evaluated on isolated coronary arteries on organ chambers. Determination of eNOS expression and the phosphorylation level of eNOS were determined by Western blot analysis. In the presence of indomethacin, EGE caused pronounced relaxations in endothelium-intact but not in endothelium-denuded coronary artery rings. Relaxations to EGE were significantly reduced by Nω-nitro-L-arginine (L-NA, a competitive inhibitor of NO synthase), slightly but not significantly by charybdotoxin plus apamin (two potent inhibitors of EDHF-mediated responses) and abolished by the combination of L-NA and charybdotoxin plus apamin. Relaxations to EGE were abolished by the membrane permeant, SOD mimetic, MnTMPyP, and significantly reduced by wortmannin, an inhibitor of PI3-kinase. Exposure of endothelial cells to EGE increased the phosphorylation level of eNOS at Ser1177 in a time and concentration-dependent manner. MnTMPyP abolished the EGE-induced phosphorylation of eNOS. In conclusion, the obtained data indicate that EGE induces pronounced endothelium-dependent relaxations of the porcine coronary artery, which involve predominantly NO. The stimulatory effect of EGE on eNOS involves the redox-sensitive phosphorylation of eNOS at Ser1177 most likely via the PI3-kinase pathway.

The aqueous extract of the Parinari excelsa barks at doses of 100 and 300 mg/kg/day for 7 days has a significant antihyperglycemic effect on alloxan-induced diabetic rats. At the same dose the acute oral administration of aqueous extract of the P. excelsa barks (100 and 300 mg/kg) induced a significant decrease of blood glucose on glucose-loaded normoglycaemic rats. Our results seem to confirm the rational bases for its use in traditional medicine.

Studies of vascular reactivity during late pregnancy were performed to investigate the previously described hyporeactivity to vasopressors. Two groups of seven control (nonpregnant) and seven late pregnant (day 20) Wistar rats were used. Rubbed (E-) segments from thoracic aorta were studied for contractile studies in a Krebs solution containing either 1.25 or 2.50 mmol/L Ca concentration. Norepinephrine (NE; 10-9-3 x 10-5) or depolarization induced (KCl, 100 mmol/L) contractions are given as mN/mm2. With 2.50 mmol/L Ca, the maximal contraction to NE in E-segments is decreased in late pregnant rats compared with nonpregnant rats. However, this difference disappears when calcium concentration is set to 1.25 mmol/L Ca, the physiological value for free calcium concentration in extracellular fluid. For the contraction induced by opening of voltage operated calcium channels (KCl depolarization), a decreased maximal tension is also obtained in the pregnant rats compared with nonpregnant only with 2.50 mmol/L Ca concentration. It appears that aortic response to vasoconstrictors is modulated by extracellular calcium concentration in a different way between pregnant and nonpregnant rats.