No description available.

No description available.

No description available.

Heterocycles that contain nitrogen, such as piperidine, pyrrolidine and tropane, are widespread as natural product alkaloids and serve as templates for many bioactive drugs and drug candidates. The intent of this research is to the develop asymmetric syntheses of piperidine-containing syn and anti 1,3-amino alcohols as well as tropinone and tropane-containing derivatives using sulfinimines (N-sulfinyl imines) as precursors for acid-catalyzed cascade cyclizations. Chiral N-sulfinyl b-amino ketones derived from N-sulfinyl b-amino Weinreb amides, serve as novel and direct precursors to syn and anti N-sulfinyl 1,3-amino alcohols through stereoselective reductions. General reduction conditions have been developed for a variety of substrates. This methodology was applied to a concise formal synthesis of the piperidine-containing natural product, (-)-pinidinol, through an intramolecular cascade-cyclization of a masked-oxo N-sulfinyl 1,3-amino alcohol. Special conditions were found for the syn reduction of these substrates. Tropinones and tropanes are structural motifs which encompass many interesting bioactive natural products such as cocaine and scopolamine. The synthesis of these tropinone derivatives, using an asymmetric and intramolecular cascade reaction, allows for facile functionalization of one of the bridgehead carbons. This opens doors to novel derivatives of (-)-cocaine which can be used as potential addiction therapeutics or in new SAR studies of dopamine reuptake transporter blockers. Here a five-membered cyclic imine can be formed through the acid-catalyzed intramolecular cyclization of acyclic ketal-protected N-sulfinyl ketones. After reaction with an acylating agent, the tropinone nucleus can be formed through an intramolecular Mannich reaction of an N-acyl iminium ion. / Chemistry

Le traitement de la dépression reste insatisfaisant. Avec un tiers des patients ne répondant à aucun traitement proposé, un délai d’action long, et des effets secondaires non négligeables, la nécessité de développer de nouvelles stratégies thérapeutiques devient urgente. La luminothérapie, traitement de choix de la dépression saisonnière, a été montrée depuis une trentaine d’années comme présentant également un intérêt pour le traitement des dépressions non saisonnières, unipolaires comme bipolaires. Cependant, les mécanismes d’actions sous-tendant l’effet antidépresseur de la lumière restent mal connus. L’objectif de ce travail de thèse est de comprendre, à l’aide d’un modèle original de dépression, les mécanismes neurobiologiques à l’origine de l’effet antidépresseur de la lumière. Nous avons pour cela développé un modèle de dépression combinant stress par la nage forcée et isolation sociale. Nos résultats montrent que ce protocole induit chez les animaux des comportements pseudo-dépressifs stables et résistants à des traitements classiques (escitalopram) mais également à la kétamine, utilisée récemment en étude clinique pour traiter certains patients réfractaires. Si la lumière seule à forte irradiance (Bright light stimulation, BLS, 1000 lux, une heure par jour) n’a pas d’effet antidépresseur, nous avons démontré dans notre modèle de dépression résistante que la BLS permettait de potentialiser la réponse antidépressive d’une combinaison de kétamine et de scopolamine (utilisée récemment comme d’antidépresseur potentiel) à des doses sous-efficaces. Cet effet est modulé par la sérotonine. En effet, la déplétion en tryptophane, précurseur de la sérotonine, bloque l’effet antidépresseur de cette combinaison. De manière intéressante, nous avons découvert que l’effet potentialisateur de la lumière met en jeu les astrocytes de l’habénula latérale. Ces données suggèrent que la lumière associée à la kétamine et la scopolamine, ciblerait les astrocytes afin de rétablir une activité normale dans l’habénula latérale, désinhibant les centres monoaminergiques, menant ainsi à une réponse antidépressive. Ce travail a permis de mieux comprendre les mécanismes à l’origine de la potentialisation de l’effet antidépresseur par la lumière et pourrait aider à optimiser les stratégies thérapeutiques chez les patients déprimés résistants aux traitements incluant la kétamine / The treatment of depression remains unsatisfactory. Given that one third of patients does not respond to any of the proposed treatments, the long delay of action, and the significant side effects, there is an urgent need to develop new and effective therapeutic strategies. Light, a treatment of choice for seasonal depression, has been of particular interest since thirty years in the treatment of non-seasonal unipolar and bipolar depressions. However, the mechanisms underlying the antidepressant effect of light therapy remains poorly understood. The aim of this thesis was to understand, using an original model of depression, the neurobiological mechanisms of the antidepressant effect of light stimulation. We developed an original model of depression combining forced swimming stress and social isolation. Our results showed that the latter protocol induced pseudo-depressive behaviors that were stable and resistant to classical treatments (escitalopram), but also ones recently tested in clinical studies to treat refractory patients (ketamine). Although bright light stimulation (BLS, 1000 lux, one hour per day) failed to present an antidepressant effect, we demonstrated in our model of resistant depression that BLS potentiated the antidepressant response of sub-effective doses of ketamine and scopolamine combination. This effect was modulated by serotonin tone. Indeed, this effect was blocked by tryptophan depletion. Remarkably, we unveiled that the potentiating action of light involves lateral habenula astroglia. These results suggest that light stimulation, associated with ketamine and scopolamine combination, modulated astroglia, in order to restore a normal activity in the lateral habenula and to regulate monoaminergic systems, leading to an effective antidepressant response. This work allowed to better understand the mechanisms responsible of the potentiating action of light and will certainly help in optimizing therapeutic strategies in treatment-resistant depression

Datura innoxia Mill., une plante de la famille des Solanacées synthétisant des métabolites secondaires, dont les alcaloïdes tropaniques, a été utilisée comme modèle pour cette étude portant sur les cultures en hydroponie. Nous avons déterminé et hiérarchisé les paramètres environnementaux (biotiques et abiotiques) permettant d’améliorer croissance et production de métabolites. La réponse de la plante dépend de l’approvisionnement en oxygène de la solution nutritive, de la température perçue tant niveau des parties aériennes qu’au niveau racinaire. Une augmentation de l’intensité d’éclairage n’améliore pas la teneur en alcaloïdes de la plante mais l’utilisation de lumière orange engendre un changement des paramètres de croissance et des teneurs en molécules recherchées. Nous avons également montré que la présence de microflore dans le milieu de culture provoque une dégradation des molécules d’intérêt et altère leur accumulation dans la plante. Par contre, A. rhizogenes a un effet favorable sur la croissance de la biomasse et la biosynthèse d’alcaloïdes tropaniques dans la plante. L’état transgénique des racines, issues de co-culture hydroponique de Datura innoxia avec A. rhizogenes TR7, a été estimé par une vérification précoce et confirmé par des analyses moléculaires. Nous avons pu mettre en évidence les modifications du phénotype racinaire et les mécanismes d'interaction plante-microorganisme. L’inoculation des agrobactéries peut donner lieu à des transferts naturels de gènes induisant ainsi l’obtention d’un pool racinaire chimérique regroupant des racines normales et des racines transformées. Ces travaux ont ouvert de nouvelles perspectives en vue de déterminer la capacité de production de métabolites secondaires par des plantes en culture hors sol, de manière à obtenir une biomasse riche en molécules recherchées / Datura innoxia Mill. a plant species belonging to Solanaceous family, produces hyoscyamine and scopolamine as two main tropane alkaloids. It has been studied in the present work for the development of hydroponic based secondary metabolites bioproduction. More specifically, biotic and abiotic environmental factors have been analysed in order to improve growth and alkaloid accumulation in plant tissues. Oxygen concentration in the nutrient solution is proved to be important for both biomass and compound production in temporary immersion culture conditions occur as one optimum. Temperature has also a major effect, directly and most probably through oxygen solubility and root needs. We showed that artificial light may positively complete natural one but the kind of spectrum must be chosen carefully. From this point of view, orange light from High Pressure Natrium Vapour light showed better results than classical white light. Nitrogen (NO3-15mM) and pH (5 to 6) management may lead to culture optimization. We also show that well chosen wild Agrobacterium rhizogenes strains may be added to the hydroponic nutrient solution in order to improve growth and alkaloid bioproduction. This result is due to the multi occurrence of genetic transformation events. Our results lead to a first classification for impacts of biotic and abiotic factors. It opens new window for plant milking technology industrial development

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O Gengibre (Zingiber officinale Roscoe) à uma planta bastante apreciada em todo o mundo, nÃo apenas como um condimento, mas tambÃm por suas importantes propriedades medicinais. Os efeitos comportamentais e neuroquÃmicos do Ãleo essencial do gengibre - OEG foram estudados em camundongos tratados diariamente com o Ãleo essencial de gengibre (OEG 25, 50 e 100 mg/Kg, i.p. e v.o.). No sÃtimo dia de tratamento foram realizados os testes do labirinto em cruz elevado (LCE), campo aberto (CA), rota rod (RR), esquiva-passiva (EP) e teste dos tremores induzidos por oxotremorina. No oitavo dia do protocolo, os animais que receberam OEG (100 mg/Kg, i.p.) foram sacrificados para o estudo dos efeitos neuroquÃmicos do OEG em hipocampo e corpo estriado. Os efeitos tÃxicos do OEG foram estudados em camundongos (tratados com Ãnica administraÃÃo de OEG 200, 400 e 800 mg/Kg, i.p.) e ratos (nos quais foi induzida lesÃo hepÃtica por CCl4, e tratados com OEG 50, 100 e 200 mg/Kg, i.p. em Ãnica administraÃÃo). Os resultados mostraram que o OEG nÃo possui efeito ansiolÃtico de acordo com o modelo do LCE; no CA, o OEG (50 e 100 mg/Kg, i.p.) apresentou efeito sedativo ao reduzir o NC, o NG e NR em 37%, 28% e 75%, respectivamente. Foi observada, tambÃm, a ocorrÃncia de efeito dose-dependente da droga, cujo efeito mÃximo parece ser obtido com a dose de 100 mg/Kg (i.p.). A administraÃÃo oral do OEG tambÃm produziu sedaÃÃo, porÃm o efeito sà foi observado no grupo tratado com a dose maior do Ãleo essencial. No modelo do RR, o OEG nÃo produziu alteraÃÃo significativa na coordenaÃÃo motora dos animais tratados. No modelo da EP, o OEG produziu um dano cognitivo nos animais tratados com a dose de 100 mg/Kg, i.p. e v.o. Mesmo apÃs 24 horas da administraÃÃo da droga, o dano ainda era evidente. Quando associado à escopolamina, o OEG (50 e 100 mg/Kg, i.p. e v.o.) potencializou o efeito amnÃsico da droga. O efeito anticolinÃrgico do OEG (100 mg/Kg, i.p.) foi comprovado ao reverter os tremores induzidos por oxotremorina em camundongos. Em relaÃÃo aos efeitos neuroquÃmicos do OEG em corpo estriado, a droga diminuiu a concentraÃÃo de DA, aumentou NE, DOPAC e 5HT em 40%, 22%, 15% e 81%, respectivamente. No hipocampo observou-se que houve uma diminuiÃÃo de DA, DOPAC e um aumento de 5HT em 75%, 64% e 81%, respectivamente. A diminuiÃÃo de DA no corpo estriado explicaria o efeito sedativo da droga, e o conjunto de alteraÃÃes observadas no hipocampo parece contribuir tambÃm para o efeito amÃsico do OEG. O estudo dos efeitos tÃxicos do OEG revelou que a droga à relativamente segura e destituÃda de efeitos tÃxicos significativos nos protocolos utilizados no presente estudo. A administraÃÃo aguda do Ãleo essencial (200, 400 e 800 mg/Kg, i.p.) nÃo produziu outro efeito sobre os animais, a nÃo ser a sedaÃÃo, efeito jà observado com doses menores do Ãleo essencial. A administraÃÃo diÃria do OEG tambÃm nÃo produziu efeitos tÃxicos alÃm de diarrÃia observada nos animais tratados com a droga nas doses de 50 e 100 mg/Kg, i.p. e v.o. O OEG (200 mg/Kg, i.p.) mostrou-se efetivo ao reverter a lesÃo hepÃtica induzida por CCl4 em ratos. O tratamento com o Ãleo essencial na dose de 200 mg/Kg, i.p. reduziu em 35% e 23% a atividade das enzimas ALT e AST, respectivamente. O OEG parece exercer a aÃÃo hepatoprotetora ao combater a peroxidaÃÃo lipÃdica gerada pelo metabolismo hepÃtico do CCl4 que produz radicais livres, altamente lesivos / Ginger (Zingiber officinale Roscoe) is a plant largely used around the world, not just as a spice, but also for its medicinal properties. The behavioral and neurochemical effects were studied in mice daily administered with the essential oil of Ginger (EOG 25, 50 e 100 mg/Kg, i.p. and p.o.). In the 7th day of treatment, it was assessed the elevated-plus maze (EPM), open field (OF) rota rod (RR), passive avoidance (PA) and oxotremorine-induce tremor tests, to evaluate the behavioral effects of the drug. In the 8th day of the protocol, mice that received EOG (100 mg/Kg, i.p.) were killed to study the neurochemical effects of EOG on hipoccampus and striatum. Toxic effects of EOG were studied in mice (that received a single administration of EOG 200, 400 e 800 mg/Kg, i.p.), and rats (with hepatic injury induced by CCl4, and treated with EOG 50, 100 e 200 mg/Kg, i.p. in a single administration). Results showed that OEG does not have anxiolytic effects on EPM test; in OF test, EOG (50 e 100 mg/Kg, i.p.) showed a sedative effect, decreasing the number of crossings, grooming and rearing in 37%, 28% and 75%, respectively, with OEG 100 mg/Kg. It was also observed a dose-dependent effect of the drug, which maximum effect observed with 100 mg/Kg (i.p.) of the drug. The oral administration of EOG also induced a sedative effect, occuring only in the group treated with the highest dose of the essential oil. In RR test, EOG did not induce any significant alteration on motor coordination of the animals. In PA test, EOG produced a cognitive impairment in animals treated with EOG100 mg/Kg, i.p. and p.o. Even 24h after the drug administration, the cognitive impairment was still evident. When associated with scopolamine, EOG (50 e 100 mg/Kg, i.p. and p.o.) potentiated the amnesic effect of scopolamine. The anticholinergic effect of EOG (100 mg/Kg, i.p.) was proved to reverse the tremors induced by oxotremorine in mice. EOG, in striatum decreased DA and increased the concentrations of DOPAC, NE and 5HT in 40%, 15%, 22% and 81%, respectively. In hippocampus, OEG decreased DA, DOPAC and increased 5HT in 75%, 64% e 81%, respectively. The decrease of DA in striatum justifies the sedative effect of the drug and the aterations observed on hipoccampus seem to contribute to the amnesic effect of EOG. The study of toxic effects of EOG showed that the drug is relatively safe and it does not have any toxic effects, according to the protocols established in the present work. The acute administration of the essential oil (200, 400 and 800 mg/Kg, i.p.) did not induce any other toxic effect besides sedation. The daily administration of EOG did not produce any toxic effect, besides the diarrhea, observed in animals that received EOG 50 and 100 mg/Kg, i.p. and p.o. EOG (200 mg/Kg, i.p.) was effective in reversing the hepatic injury induced by CCl4 in rats. The treatment with the essential oil (200 mg/Kg, i.p.) reduced in 35% and 23% the activity of the enzymes ALT and AST, respectively. EOG seems to exert its hepatoprotective action by decreasing lipid peroxidation generated by the hepatic metabolism of CCl4, wich produces extremely danous free radicals

Thesis (M.A.)--University of North Carolina at Wilmington, 2003. / Includes bibliographical references (leaves : [84]-89).

No description available.

Purpose: To establish a tool, termed as antimuscarinic activity (AMA), to predict the incidence of antimuscarinic adverse events (AMAEs).Methods: A literature review, focused on drugs having off-target interaction with muscarinic receptors, was performed. Prototypical drugs olanzapine, diphenhydramine, paroxetine were selected for the analysis. Scopolamine and darifenacin were included as positive and negative controls, respectively. Physiochemical properties, pharmacokinetic data, and clinical incidence of AMAEs for the selected drugs were collected from reported literature. Extrapolation of literature data was carried-out to obtain exposure data. To determine the drugs muscarinic affinity (Ki values), experiments were performed using 3H-QNB and membrane suspensions of M1, M2, and M3. Cmax, values were combined with Ki values to generate the relevant AMA. Validation of the AMA biomarker was carried-out against the reported AMAEs incidence. Results: With the exclusion of scopolamine and olanzapine for CNS and peripheral AMAEs, respectively, AMA ranking was related to the drugs AMAEs.