Production de matières premières et fabrication des médicaments à base de plantes médicinales

Les plantes constituent un réservoir pour les pharmacopées du monde. Plusieurs médicaments importants sont fabriqués à partir des substances actives d’origine végétales. En outre de nombreux médicaments modernes ont été fabriqués à partir de ces matières premières. Les plantes médicinales sont utilisées directement sous forme fraîche, sèche ou transformée, stabilisée, ou extrait ou formulée avec d’autres plantes ou excipients de synthèse. Dans tous les cas, la matière végétale utilisée pour fabriquer la forme posologique doit faire preuve de son efficacité, son innocuité et être de qualité conforme aux exigences de la Pharmacopée Européenne pour les phytomédicaments, garantissant ainsi sa sécurité d’emploi. Pour ce faire, l’Organisation Mondiale de la Santé (OMS) a mis à la disposition des états membres des guides et standards permettant d’harmoniser et de sécuriser leur utilisation. Ainsi de nombreux pays africains ont adopté ces outils après des modifications appropriées pour faire progresser la recherche et le développement (R&D) de médicaments à base de plante. Le but de ce travail était de faire une synthèse des différentes étapes de production, de contrôle qualité et de  standardisation des matières premières issues des plantes médicinales et des médicaments à base de plantes médicinales.Mots clés : Pharmacopée, médicaments, médecine traditionnelle, sécurité d’emploi, phytomédicaments. English title: Production of raw materials and manufacturing of drugs from medicinal plants Plants are a reservoir for the world's pharmacopoeias. Several important medicines are made from active substances of plant origin. In addition, many modern medicines have been made from these raw materials. Medicinal plants are used directly in fresh, dry or processed, stabilized, or extracted form or formulated with other plants or synthetic excipients. In all cases, the herbal material used to manufacture the dosage form must demonstrate its efficacy, safety and be of a quality that meets the requirements of the European Pharmacopoeia for phytomedicines, thus ensuring its safe use. To this end, the World Health Organization (WHO) has made available to Member States guides and standards to harmonize and secure their use. Thus, many African countries have adopted these tools after appropriate modifications to advance research and development (R&D) of plant-based drugs. The aim of this work was to make a synthesis of the different stages of production, quality control and standardization of raw materials from medicinal plants and herbal medicines.Keywords: Pharmacopoeia, drugs, traditional medicine, safe use, phytomedicines

nmMLCK is essential to trigger endothelial dysfunction, interleukin-6 secretion and endothelial permeability in an experimental model of intermittent hypoxia

National audienc

nmMLCK is essential to trigger endothelial dysfunction, interleukin-6 secretion and endothelial permeability in an experimental model of intermittent hypoxia

National audienc

Pharmacological Evaluation of the Bronchorelaxant Effect of Waltheria indica L. (Malvaceae) Extracts on Rat Trachea

Waltheria indica L. (Malvaceae) is a plant used in Burkina Faso for the treatment of various ailments including asthma. The aim of the study was to evaluate the pharmacological relaxant effect of the leafy stem extracts of Waltheria indica and thereby verify claim of use in treating asthma. Aqueous decoction and hydroalcoholic extracts obtained from the powdered leafy stems were screened for the presence of some phytoconstituents. The in vitro relaxant effect of the two extracts was evaluated on acetylcholine- (ACh 10−5 M) and potassium chloride- (KCl 6 × 10−2 M) induced contractions on rat-isolated tracheal preparations. To examine whether the potassium (K+) channels are involved in the relaxant effect, glibenclamide, an ATP-sensitive potassium channel inhibitor, was used. Moreover, to assess the safety of the extracts, acute oral toxicity was carried out on mice. The phytochemical screening revealed the presence of alkaloids, flavonoids, saponins, steroids, triterpenoids, tannins, and coumarins in the hydroalcoholic extract. Tannins, steroids, triterpenoids, and coumarins were not detected in the aqueous decoction. With respective EC50 values of 1.517 ± 0.002 mg/mL and 1.433 ± 0.001 mg/mL on ACh-and KCl-provoked contractions, the hydroalcoholic extract was found more potent in relaxing the isolated rat tracheal preparations compared to the aqueous decoction. In the presence of glibenclamide, the relaxant effect of the hydroalcoholic extract (EC50 = 0.191 ± 0.002 mg/mL) increased and was higher than that of the aqueous decoction. At dose of 5000 mg/kg of body weight, the extracts did not produce deaths or any significant changes in the general behavior of mice. The results suggest that different mechanisms including modulation of calcium and potassium channels, particularly the ATP-sensitive K+ channels, could be involved in the relaxation effect. These findings could justify the traditional use of W. indica in the management of asthma

Ethanol Extract of Leaves of Cassia siamea Lam Protects against Diabetes-Induced Insulin Resistance, Hepatic, and Endothelial Dysfunctions in ob/ob Mice

International audienceDespite long traditional utilization and some reports on the antihyperglycemic and antihyperlipidemic action of Cassia siamea, the mechanisms involved have not been investigated yet. Thus, the objective of the present study was to investigate whether and how oral administration of the ethanolic extract of Cassia siamea Lam leaves (LECS) improves glucose and insulin homoeostasis, liver damage, and endothelial dysfunction in an experimental model of type 2 diabetes, the leptin-deficient ob/ob mice. Oxidative stress and protein expression of insulin-dependent and insulin -independent signaling pathways were studied. Obese ( ob/ob) vs. control (ob/+) mice were treated daily with intragastric administration of either vehicle or LECS (200 mg/kg, per day) for 4 weeks. Fasting blood glucose, body weight, food intake, glucose and insulin tolerance, oxidative stress, and liver damage as well as vascular complications with respect to endothelial dysfunction were examined. Administration of LECS in obese mice significantly reduced blood glucose and insulin levels, improved glucose tolerance and insulin sensitivity, and restored the increase of circulating AST and ALT without modification of body weight and food intake. These effects were associated with increased activity of both insulin and AMPK pathways in the liver and skeletal muscles. Of particular interest, administration of LECS in obese mice completely prevented the endothelial dysfunction resulting from an increased NO· and decreased reactive oxygen species (ROS) production in the aorta. Altogether, oral administration of LECS remarkably attenuates features of type 2 diabetes on glucose, hepatic inflammation, insulin resistance, endothelial function, and vascular oxidative stress, being as most of these effects are related to insulin-dependent and insulin-independent mechanisms. Therefore, this study points for the therapeutic potential of Cassia siamea in correcting both metabolic and vascular alterations linked to type 2 diabetes

Effet gastroprotecteur et potentiel mécanisme d’action antiulcéreuse d’extraits de fruits de Acacia nilotica var adansonii (Guill. et Perr.) O. Ktze (Mimosaceae)

Acacia nilotica est utilisée par les tradipraticiens dans la prise en charge des ulcères gastroduodénaux au Burkina Faso. L’objectif de cette étude était d’évaluer l’effet gastroprotecteur et le potentiel mécanisme d’action des extraits aqueux et hydroéthanolique des fruits secs de Acacia nilotica L. (Mimosaceae) sur un modèle d’ulcère gastrique induit par l’éthanol chez la souris. Un criblage phytochimique et un dosage des composés phénoliques ont été réalisés sur les extraits aqueux et hydroéthanolique des fruits secs de Acacia nilotica. L’étude de la toxicité et de l’effet gastroprotecteur a été évaluée chez la souris. Ensuite, une évaluation de l’effet spasmolytique, du pouvoir antioxydant avec les méthodes DPPH et ABTS des extraits ont été réalisés. La forte teneur en composés phénoliques et flavonoïdes totaux a été obtenue avec le décocté. La toxicité aiguë étudiée a permis de classer les extraits étudiés comme des substances faiblement toxiques. Le macéré hydroéthanolique a présenté le meilleur effet spasmolytique. L’étude de l’activité antiradicalaire par la méthode de DPPH a permis d’obtenir des CI50 qui ont varié de 6,79 ± 0,86 à 9,39 ± 0,01 μg/ml et la méthode ABTS a permis d’obtenir un TEAC qui a varié de 0,19 à 0,87 mg ET/g. Cependant le décocté aqueux a présenté le meilleur effet gastroprotecteur à la dose de 400 mg/kg avec 97,50 %. La forte teneur en composé phénoliques et les propriétés pharmacologiques des extraits pourraient justifier l’utilisation de Acacia nilotica par les tradipraticiens dans la prise en charge des ulcères gastroduodénaux.Mots-clés: Acacia nilotica, gastroprotecteur, antioxydant, spasmolytique, ulcèreEnglish Title: Gastroprotective effect and potential anti-ulcer mechanism of action of fruit extracts of Acacia nilotica var adansonii (Guill. et Perr.) O. Ktze (Mimosaceae)English AbstractIn Burkina Faso, medicinal plants are used by traditional healers in the of peptic ulcers including Acacia nilotica. This study was aimed to evaluate the gastroprotective effect of aqueous and aqueous-ethanolic extracts of A. nilotica dry fruits on a model of gastric ulcer induced by ethanol in mice. Phytochemical screening and determination of the phenolic compounds were carried out on the aqueous and aqueousethanolic extracts of dry fruits from A. nilotica. Also, a study of the toxicity and the gastroprotective effect was evaluated in NMRI mice. Then, an evaluation of spasmolytic effect on contractions induced by acetylcholine and barium chloride, of the antioxidant power with DPPH and ABTS methods of extracts were carried out. The highest content of phenolic and flavonoids was obtained with the aqueous extract. Acute toxicity allowed to classify the extracts as weakly toxic substances. Hydroethanolic extract showed the best released effect on contractions induced by acetylcholine and barium chloride. Extracts IC50 varied from 6.79 ± 0.86 to 9.39 ± 0.01μg/mL using DPPH method, and ABTS method TEAC ranged from 0.19mgET / g to 0.87mg ET / g. However aqueous decoction showed a better protection against gastric mucosa at dose of 400 mg/kg with 97.50%. High content of phenolic compounds and pharmacological effects of extracts justify Acacia nilotica use by traditional healer in peptic ulcer management.Keywords: Acacia nilotica, gastroprotective, antioxidant, spasmolytic, ulce