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O jejum regula diferencialmente a corticosterone binding globulin (CBG) plasmática, o receptor de glicocorticóide (GR) e proteínas que controlam a progressão do ciclo celular na mucosa gástrica de filhotes e ratos adultos / Fasting differentially regulates plasma corticosterone-binding globulin, glucocorticoid receptor and cell cycle in the gastric mucosa of pups and adult ratsOgias, Daniela 18 September 2009 (has links)
O estado nutricional influencia o crescimento gástrico, e enquanto a proliferação celular é estimulada pelo jejum em filhotes, ela é inibida em ratos adultos. A corticosterona também age no desenvolvimento, e seus efeitos são regulados pela corticosterone binding globulin (CBG) e receptores de glicocorticóides (GR). Para investigar se a atividade da corticosterona responde ao jejum e como possíveis mudanças poderiam controlar o ciclo celular epitelial gástrico, nós avaliamos diferentes parâmetros durante a progressão do jejum em ratos de 18 e 40 dias de vida pós-natal. A restrição alimentar induziu um aumento de corticosterona no plasma em ambas as idades, mas apenas em filhotes o binding da CBG se elevou após o jejum curto, permanecendo alto até o final do tratamento. O jejum aumentou a atividade transcricional do GR na mucosa gástrica e os níveis protéicos, porém o efeito foi mais pronunciado em adultos. Além disso, observamos que nos filhotes, o GR é principalmente citoplasmático, enquanto em animais adultos, o receptor é acumulado no núcleo durante o jejum. As proteínas HSP 70 e HSP 90 foram diferencialmente reguladas, e podem contribuir para a estabilidade do GR no citoplasma em filhotes, e para o trânsito de GR para o núcleo em animais adultos. Quanto ao ciclo celular epitelial, observamos que em filhotes, ciclina D1 e p21 aumentaram durante o jejum, enquanto em ratos adultos, a ciclina E diminuiu e a p27 aumentou muito. Assim, nós demonstramos que a atividade da corticosterona é diferencialmente regulada pelo jejum em filhotes e ratos adultos, e que as variaçõe observadas poderiam atenuar um possível efeito supressor durante o desenvolvimento pós-natal. Sugerimos que este mecanismo pode estimular a proliferação celular e possibilitar o crescimento da mucosa gástrica durante condições nutricionais adversas. / The nutritional status influences gastric growth, and interestingly, whereas cell proliferation is stimulated by fasting in suckling rats, it is inhibited in adult animals. Corticosterone takes part in the mechanisms that govern development, and its effects are regulated in particular by corticosterone binding globulin (CBG) and glucocorticoid receptor (GR). To investigate whether corticosterone activity responds to fasting and how possible changes might control gastric epithelial cell cycle, we evaluated different parameters during the progression of fasting in 18- and 40-d-old rats. Food restriction induced higher corticosterone plasma concentration at both ages, but only in pups did CBG binding increase after short and long-term treatments. Fasting also increased gastric GR at transcriptional and protein levels, but the effect was more pronounced in 40-d-old animals. Moreover, in pups, GR was observed in the cytoplasm, whereas in adults, it accumulated in the nucleus after the onset of fasting. HSP 70 and HSP 90 were differentially regulated, and might contribute to the stability of GR and to the high cytoplasmic levels in pups and elevated shuttling in adult rats. As for gastric epithelial cell cycle, whereas cyclin D1 and p21 increased during fasting in pups, in adults, cyclin E slowly decreased concomitant with higher p27. In summary, we demonstrated that corticosterone function is differentially regulated by fasting in 18- and 40-d-old rats, and such variation might attenuate any possible suppressive effects during postnatal development. We suggest that this mechanism could ultimately increase cell proliferation and allow regular gastric growth during adverse nutritional conditions.
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Le canal calcique de type L, une cible directe de l’aldostérone dans les cardiomyocytes / L-type Calcium Channel, a direct target of aldosterone in cardiomyocytesAuguste, Gaëlle 19 January 2015 (has links)
Ces dernières décennies ont mis à jour une implication pathologique nouvelle del’aldostérone, via le récepteur aux minéralocorticoïdes (RM) dans le coeur. L’ensemble desdonnées issues des études expérimentales et des essais cliniques suggère une association délétèreentre l’aldostérone et la survenue d’arythmies. L’utilisation d’antagonistes du RM prévient cesarythmies. Cependant, les voies de signalisations, comme les mécanismes moléculaires soustendantces effets bénéfiques du blocage des RM demeurent incertains. Nous avons accumulésdes preuves d’une modulation de la signalisation calcique dans le cardiomyocyte, et en particulierde l’influx calcique (Ca2+) au travers du canal Ca2+ de type L (LTCC). Celui-Ci pourrait être unecible primaire de l’aldostérone et du RM dans les cardiomyocytes ventriculaires. Toutefois, lesmécanismes par lesquels l’aldostérone et le RM régulent l’expression du LTCC restent à définir.Au cours de ces travaux menés sur cardiomyocytes de rats nouveau-Nés, nous avonsétudiés les évènements moléculaires par lesquels l’aldostérone exerce ses effets sur le CaV1.2,qui correspond à la sous-Unité principale du LTCC formant le pore du canal ; cette protéine estcodée par le CACNA1C. Par microscopie confocale, nous avons suivi en temps réel le traffickingnucléo-Cytoplasmique du RM couplé à la GFP en réponse à l’aldostérone, démontrant ainsi queles RM cardiaques sont fonctionnels. Le traitement durant 24 heures des cardiomyocytes avec del’aldostérone montre une augmentation dose-Dépendante des protéines et de l’ARN messager duCaV1.2. L’utilisation de la technique du gène rapporteur de la luciférase permet l’analyse del’activité du promoteur du CaCNA1C. Celui-Ci montre une activité transcriptionnelle dose ettemps dépendante en réponse à l’aldostérone. De plus, ces effets sont dépendant des RM carinhibés en présence de RU28318, un antagoniste sélectif du RM, ou par l’utilisation de siRNAdirigés contre le RM. L’analyse in silico de la séquence du promoteur du CaCNA1C nous a permisd’identifier cinq séquences putatives correspondant à des éléments de réponse auxglucocorticoïdes (GRE). La mutation du site le plus lointain du site d’initiation de la transcriptionne révèle aucun changement dans les réponses transcriptionnelles induites par un RM humainconstitutivement actif (hMRΔ5,6) ou dans les réponses doses-Dépendantes de l’aldostérone ou dela déxaméthasone, un glucocorticoïde de synthèse. La mutation des trois sites GRE putatifssuivants provoque une diminution des réponses au hMRΔ5,6 comme à l’aldostérone, alors que lesréponses à la déxaméthasone sont soit inchangées, soit augmentées. En contraste, la mutation dusite le plus proximal du promoteur augmente de façon importante l’activité transcriptionnelle dupromoteur en réponse au hMRΔ5,6, à l’aldostérone comme à la déxaméthasone.Ces résultats démontrent que le LTCC cardiaque constitue une cible directe del’aldostérone et du RM, et apportent de nouvelles perspectives quant aux conséquencesmoléculaires et fonctionnelles engendrées par l’activation délétère du système minéralocorticoïdedans la défaillance cardiaque. / During the past decades, major novel pathogenic roles of the steroid hormone,aldosterone, via the Mineralocorticoid Receptor (MR) have been identified in heart. Collectively,experimental studies and clinical trials, suggest a detrimental association between aldosteroneand life threatening arrhythmias that may be prevented by MR blockade. However, the signalingpathways and underlying mechanisms still remain elusive. We have accumulated evidence thatmodulation of Ca2+ signaling, especially Ca2+ influx via L-Type Ca2+ channel (LTCC), might bethe primary aldosterone/MR target in ventricular cardiomyocytes. Yet, the molecularmechanisms by which MR regulates expression of LTCC remain to be defined. Here, weinvestigated, in primary cultures of neonatal rat ventricular myocytes, the molecular eventscritical for aldosterone-Mediated cardiac effects on CaV1.2, the pore-Forming main subunit ofLTCC, which is encoded by the CaCNA1C gene.We showed that cardiac MR are functional as demonstrated by aldosterone-Induced MRnucleocytoplasmic trafficking observed by time-Lapse imaging of transfected GFP-Labeled MRusing confocal microscopy. Aldosterone exposure for 24 hours, induced a dose-Dependentincrease in CaV1.2 expression at both mRNA and protein levels. Analysis of the CaCNA1Cpromoter activity using luciferase reporter assays, revealed a dose- and time-Dependent activationby aldosterone. These effects were inhibited in the presence of either RU28318, a selective MRantagonist, or MR siRNA. In silico analyze enabled us to identify five putative GlucocorticoidResponse Elements (GRE) within the CaCNA1C promoter sequence. The mutation of the mostdistal GRE from Transcription Start Site (TSS) did not altered responses either elicited by theconstitutively active human MR (hMRΔ5,6) or dose-Dependent effects of aldosterone anddexamethasone (a synthetic glucocorticoïd with minimal MR effect). Mutations of the three nextones decreased responses to hMRΔ5,6 and aldosterone, whereas dexamethasone responses wereeither unchanged or increased. In sharp contrast, the mutation of the most proximal GRE fromTSS, increased responses to hMRΔ5,6, aldosterone and dexamethasone.These results provide new insights into the molecular mechanisms associated with cardiacMR activation, and suggest that LTCC is a primary MR target, with subsequent molecular andfunctional consequences that could lead to MR-Related cardiac dysfunction.
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Papel dos glicocorticóides endógenos na expressão de moléculas de adesão envolvidas na interação leucócito-endotélio / Role of endogenous glucocorticoids in the expression of adhesion molecules involved in the leukocyte-endothelium interactionCavalcanti, Danielle Maia de Holanda 16 September 2005 (has links)
Os glicocorticóides endógenos (GCen) são moduladores importantes das reações inflamatórias, com papel em diferentes aspectos do processos. Neste contexto, tem sido demonstrado que os GCen controlam a migração de leucócitos para os focos de lesões, e um dos mecanismos propostos tem sido o efeito inibitório sobre os fenômenos de interação leucócito-endotélio. Uma vez que as moléculas de adesão medeiam os processos de interação celular, tem sido evidenciado que os GCen controlam, direta ou indiretamente, a expressão destes receptores nas membranas celulares na vigência de estresse de diferentes origens. No entanto, a literatura ainda é fragmentária e controversa quanto aos mecanismos exatos desta interferência. Desta forma, este trabalho tem por objetivo investigar o papel dos GCen sobre a expressão de moléculas de adesão envolvidas na interação leucócito-endotélio, e os possíveis mecanismos intracelulares responsáveis pelos efeitos. A deficiência de GCen foi induzida em ratos Wistar machos, adultos por adrenalectomia bilateral. A participação de receptores de glicocorticoides (GC) foi avaliada em ratos normais tratados com o antagonista RU 38486. Animais falso-operados (FO), ou normais (N) foram empregados como controles. A deficiência hormonal foi constatada pela dosagem de corticosterona plasmática por radioimunoensaio e demonstraram valores significativamente baixos em animais adrenalectomizados (ADR). Ensaios de microscopia intravital mostraram que aumento exacerbado de leucócitos em comportamento \"rolling\" em vênulas pós-capilares de animais adrenalectomizados (ADR) não reflete alterações hemodinâmicas, uma vez que a deficiência hormonal não provocou modificações no diâmetro ou fluxo sangüíneo de vasos da microcirculação do músculo cremaster. No entanto, a determinação da expressão de moléculas de adesão em leucócitos circulantes por citometria de fluxo mostrou que neutrófilos de animais ADR apresentaram maior expressão de L-selectina que células de animais controles. Por outro lado, a expressão de L-selectina em granulócitos maduros presentes na medula óssea de animais ADR estava diminuída em comparação com células de animais controles. Este efeito pode estar envolvido com a maturação acelerada destas células na medula e com a neutrofilia detectada em animais ADR. É importante salientar que a estimulação de polimorfonucleares (PMN), coletados tanto do sangue como da medula, com fMLP mostrou que estas células estavam aptas a aumentar a expressão da molécula, indicando que as alterações nas suas expressões em animais ADR não são dependentes de modificações na capacidade de síntese. Adicionalmente, a ação dos GCen sobre a expressão de L-selectina parece não depender do GC, já que animais normais tratados com RU 38486 não apresentaram o mesmo padrão de alteração observada em animais ADR. Com o intuito de identificar os efeitos dos GCen sobre a capacidade individual de aderência do endotélio e do neutrófilo, ensaio de aderência in vitro foram realizados com cultura primária de célula endotelial (CE) obtida do músculo cremaster e com neutrófilos coletados da aorta abdominal. Os dados obtidos mostraram que menor número de PMN provenientes de animais ADR aderiram à CE de animal normal, mas por outro lado, a maior número de PMN de animais controles aderiram à CE de animais ADR. Em conjunto, estes dados indicam um controle diferente dos GCen sobre as células envolvidas no processo: facilitam a aderência de PMN e diminuem a aderência da CE. A investigação do papel dos GCen sobre a expressão de moléculas de adesão envolvidas no processo mostrou que os hormônios não interferem com a expressão basal de β2 integrina nos leucócitos, tanto nos circulantes quanto nos da medula. Adicionalmente, os dados de imunohistoquímica indicaram que os GCen modulam a expressão de moléculas responsáveis pela aderência. A expressão de ICAM-1 e PECAM-1 é significativamente maior no endotélio de vênulas de animais ADR que de animais controles. Associados, os dados aqui obtidos em animais ADR indicam um papel diferente dos CCen sobre a interação leucócito-endotélio. A modulação sobre a expressão de L-selectina pode estar envolvida na mobilização de neutrófilos para circulação e no comportamento rolling destas células. A subseqüente aderência dos leucócitos ao endotélio parece ser dependente de ações sobre a célula endotelial, através da modulação da expressão de moléculas da superfamília das imunoglobulinas. / The endogenous glucocorticoids (GCen) are important modulators of inflammatory reactions, acting in different aspects of the processes. In this context, it has been shown that GCen control leukocyte migration into focus of injuries, and one proposed mechanism of action is the modulation on leukocyte-endothelium interactions. Since adhesion molecules mediate cellular interactions, it has been evidenced that GCen control, direct or indirectly, the expression of these receptors on the cellular membranes during different stress conditions. However, data described in the literature are fragmentary and controversial. Then, the aim of this work was to investigate the role of the GCen on expressions of adhesion molecules involved in leukocyte-endothelium interactions and the possible intracellular mechanisms responsible for the effects. Adult male Wistar rats were submitted to bilateral adrenalectomy to induce adrenal hormone deficiency. The participation of glucocorticoid cytosolic receptor (GC) on the effects was evaluated in rats pre-treated with the glucocorticoid receptor antagonist RU 38 486. Sham-operated or normal rats were used as control. The hormone deficiency was assessed by quantification the plasmatic corticosterone by radioimmunoassay. Data showed marked lower values in adrenalectomized (ADR) than control rats. Intravital microscopy assays showed that the higher number of roller leukocytes in the postcapillary venules from cremaster muscle from ADR animals does not reflect hemodynamic alterations, given that hormonal deficiency did not modify the diameter or blood flow of microcirculation vessels. However, the determination of adhesion molecule expressions on circulating leukocytes by flow cytometry assay showed that neutrophils from ADR animals presented higher expression of L-selectin than cells from control animals. On the other hand, the expression of L-selectin on membranes of mature granulocytes in the bone marrow was decreased on cells from ADR rats. Together, these data suggest that modulation on L-selectin expression may be important target point of GE control and it may participate of the accelerated maturation of segmented cells in bone marrow, neutrophilia and in the elevated number of rolling leukocytes detected in ADR animals. It is important to emphasize that alterations on L-selectin expression on cells from ADR rats seem do not reflect an inability of its synthesis, since its expression after in vitro fMLP (formyl-Met-Leu-Phe) stimulation was not modified by hormonal deficiency. Additionally, the effect on L-selectin expression on circulating neutrophils may not be depend on the GC, since normal animal treated with RU 38486 presented expressions of L-selectin equivalent to those found in cells from control rats. To identify the effects of hormonal deficiency on individual ability of endothelium or neutrophils adherence, in vitro adherence assay was performed using both primary cultured endothelium from cremaster muscle and neutrophils collected from abdominal aorta. The results demonstrated that lesser number of PMN collected from ADR animals adhered to normal endothelium, while higher number of normal neutrophils adhered to endothelium from ADR rats. These latter results were corroborated by quantification of adhesion molecules expressions involved on adherence process by blood flow cytometer or by immunohistochemistry. The hormonal deficiency did not modify the β2 integrin expression on leukocytes, but enhanced the ICAM-1 and PECAM-1 expression on endothelium membrane of cremaster muscle venules from ADR animals. Together data obtained in ADR animals may indicate a different role of the GE on cells during the leukocyte-endothelium interaction. The modulation on L-selectin may be involved on neutrophil delivery into circulation and on the rolling of circulating neutrophils. The subsequent adherence of leukocytes to endothelium seems to be dependent on actions on endothelial cells, through modulation of expressions of immunoglobulins superfamily molecules.
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A neurobiologia da depressão em pacientes com estresse precose: o papel do eixo HPA e da função dos receptores glicocorticóides (GR) e mineralocorticóides (MR) / Neurobiology of Depression in Patients with Early Life Stress: the Role of the HPA Axis and Glucocorticoid (GR) and Mineralocorticoid (MR) Receptor FunctionCristiane von Werne Baes 24 June 2016 (has links)
Introdução: Crescentes evidências indicam que o abandono e o abuso infantis são fatores de risco para transtornos psiquiátricos. Estudos realizados tanto em animais como em humanos sugerem que o estresse nas fases iniciais de desenvolvimento pode induzir alterações persistentes na capacidade do eixo HPA em responder ao estresse na vida adulta e que esse mecanismo pode levar a uma maior suscetibilidade à depressão. Esta desregulação do eixo HPA parece estar relacionada às mudanças na capacidade dos glicocorticóides circulantes em exercer seu feedback negativo na secreção dos hormônios do eixo HPA por meio da ligação aos receptores de mineralocorticóides (MR) e glicocorticóides (GR) nos tecidos do eixo HPA. Objetivo: O objetivo deste trabalho foi avaliar a resposta do eixo HPA frente aos agonistas e antagonistas dos GR e MR em pacientes depressivos com e sem estresse precoce (EP) e controles. Metodologia: Selecionamos uma amostra total de 75 sujeitos composta por um grupo de pacientes com diagnóstico de episódio depressivo atual (n=47) e um grupo de controles saudáveis (n=28). Os pacientes foram divididos em 2 grupos de acordo com o estresse precoce: um grupo de pacientes depressivos com EP (n=33) e um grupo de pacientes depressivos sem estresse precoce (n=14). Os pacientes foram avaliados por meio da Mini Entrevista Neuropsiquiátrica Internacional (MINI-Plus), para a confirmação do diagnóstico. Para avaliação da gravidade dos sintomas depressivos foi aplicada a Escala de Depressão GRID de Hamilton (GRID-HAM-D21), sendo incluídos apenas pacientes com HAM-D21>=16. Para a avaliação do estresse precoce foi aplicado o Questionário Sobre Traumas na Infância (CTQ). Utilizamos também a Escala de Avaliação de Depressão de Montgomery-Asberg (MADRS), o Inventário de Depressão de Beck (BDI-II), o Inventário de Ansiedade de Beck (BAI), a Escala de Desesperança de Beck (BHS), a Escala de Ideação Suicida de Beck (BSI), a Escala de Impulsividade de Barratt (BIS-11) e o Questionário de Qualidade de Sono de Pittsburg (PSQI), para a avaliação dos sintomas psiquiátricos. A avaliação endócrina foi controlada por placebo, cego por parte dos controles e pacientes, não randomizada, onde os efeitos da fludrocortisona (0.5 mg), da prednisolona (5 mg), da dexametasona (0.5 mg) e da espironolactona (400mg) foram avaliados através do hormônio adrenocorticotrópico (ACTH) plasmático, do cortisol plasmático e salivar, da prolactina plasmática e do sulfato de desidroepiandrosterona (DHEA-S) plasmático. A secreção de cortisol salivar e dos hormônios plasmáticos foi avaliada em todos os sujeitos, após terem tomado no dia anterior às 22h: uma cápsula de placebo, fludrocortisona, prednisolona, dexametasona e espironolactona. A secreção de cortisol salivar foi avaliada às 22h após a tomada da medicação ou do placebo, ao acordar, 30 e 60 min após acordar e às 9h (antes da coleta plasmática), para avaliação da resposta do cortisol ao acordar (CAR) e do ritmo circadiano do cortisol (RC). Foi realizado também uma coleta plasmática as 9h nos dias seguintes após os desafios para medir o cortisol plasmático, o ACTH, o DHEA-S e a prolactina. Resultados: Os pacientes depressivos apresentaram níveis basais menores de cortisol salivar, de prolactina e de DHEA-S e níveis maiores na relação cortisol/DHEA-S. Não foram encontradas diferenças entre os pacientes depressivos e os controles nos níveis basais de ACTH, de cortisol plasmático, na CAR e no RC. Os pacientes depressivos apresentaram níveis menores de ACTH e de DHEA-S após a dexametasona e a fludrocortisona e tenderam a apresentar níveis menores de cortisol salivar após a fludrocortisona. Após a espironolactona encontramos níveis menores de ACTH, de cortisol salivar e de DHEA-S e níveis maiores no índice cortisol/DHEA-S nos pacientes depressivos. Os pacientes depressivos apresentaram também níveis menores de DHEA-S após a prednisolona, porém não foram encontradas diferenças entre os grupos nos demais hormônios avaliados após a prednisolona. Não foram encontradas diferenças no cortisol plasmático e na prolactina após os desafios entre os pacientes depressivos e os controles. Com relação à avaliação do estresse precoce nas medidas hormonais, encontramos uma tendência dos pacientes com EP apresentarem níveis menores basais de prolactina e após a fludrocortisona, a prednisolona, a dexametasona e a espironolactona do que os pacientes sem EP. No entanto, não foram encontradas diferenças entre os grupos nas demais medidas hormonais basais e após os desafios avaliadas neste estudo. Conclusão: Nossos achados fornecem evidências de que existem diversas alterações nas medidas hormonais relacionadas ao funcionamento do eixo HPA e de seus receptores GR e MR nos pacientes depressivos, associado à hipocortisolemia e um aumento do feedback inibitório mediado pelos GR e MR. Sugerem também o envolvimento da prolactina no desenvolvimento de quadros depressivos com estresse precoce, porém mais estudos são necessários para elucidarmos melhor a importância dos demais hormônios do eixo HPA e dos seus receptores em quadros depressivos com estresse precoce / Introduction: There are evidences indicating that child neglect and abuse are risk factors for psychiatric disorders. Studies that had as subjects animals or human suggest that stress in early phases of development may induce persistent changes in HPA axis response to stress in adulthood, which can lead to a greater susceptibility of developing depression. These abnormalities appear to be related to changes in the ability of circulating glucocorticoids and negative feedback on the secretion of HPA hormones through binding to glucocorticoid (GR) and mineralocorticoid receptors (MR) in HPA tissue. Aim: The aim of the present study was to assess HPA response after ingestion of GR and MR agonists and antagonists by depressive patients with and without early life stress (ELS) and controls. Methods: The sample was composed by a group of patients in current depressive episode (n=47), and a healthy control group (n=28). The depressed patients were divided in 2 groups, according to the presence or absence of ELS - a group with ELS (n=33) and a group without ELS (n=14). For diagnostic assessment, MINI International Neuropsychiatric Interview (MINI-Plus) was used. To assess the intensity of depressive symptoms, GRID-Hamilton Depression Rating Scale (GRIDHAM-D21) was applied, and for being included in the patient\'s group, subjects had to score >=16 in GRID-HAM-D21. To assess ELS, Childhood Trauma Questionnaire (CTQ) was applied. Other instruments were also used in the present study to assess psychiatric symptoms: Montgomery-Åsberg Depression Rating Scale (MADRS), Beck Depression Inventory II (BDI-II), Beck Anxiety Inventory, Beck Hopelessness Scale (BHS), Beck Scale for Suicide (BSI), Barratt Impulsiveness Scale (BIS-11), and Pittsburg Sleep Quality Index (PSQI). The neuroendocrine assessment was controlled using placebo, blind to subjects, and non-randomized. The effects of fludrocortisone (0.5 mg), prednisolone (5 mg), dexamethasone (0.5 mg), and spironolactone (400mg) were assessed by measuring plasmatic adrenocorticotropic hormone (ACTH), plasmatic and salivary cortisol, plasmatic prolactin, and plasmatic dehydroepiandrosterone sulfate (DHEA-S). The secretion of all plasmatic hormones was assessed in all subjects in blood collection sample at 9AM, after they took a pill containg placebo or fludrocortisone or prednisolone or dexamethasone or spironolactone, the day before, at 10 PM. The secretion of salivary cortisol assessed the day before 10 PM (after the ingestion of the pill), upon awakening, 30 minutes and 60 minutes after awakening, and at 9AM (before plasmatic collection), for assessed the cortisol awakening response (CAR) and the cortisol circadian rhythm (CR). At 9 AM there was a blood sample collection to assess plasmatic cortisol, ACTH, DHEA-S and prolactin. Results: Depressive patients presented lower basal levels of salivar cortisol, plasmatic prolactin and DHEA-S, and higher levels in the ratio cortisol/DHEA-S. There were no differences between depressive patients and healthy controls in basal levels of ACTH, plasmatic cortisol, in CAR, and in CR. Depressive patients had lower levels of ACTH and DHEA-S after dexamethasone and fludrocortisone, and there was a tendency of having lower salivary cortisol levels after fludrocortisone. After spironolactone, lower levels of ACTH, salivary cortisol, DHEA-S were found, and higher levels in ratio cortisol/DHEA-S were found in depressive patients. These patients also presented lower levels of DHEA-S after prednisolone, although there were no differences between groups concerning the levels of other hormones assessed after prednisolone. There were no differences found in plasmatic cortisol and prolactin levels after all challenges between depressive patients and controls. Considering ELS and hormonal level assessment, there was a tendency of patients with ELS of presenting lower levels of prolactin after placebo, fludrocortisone, prednisolone, dexamethasone, and spironolactone than patients without ELS. Nevertheless, there were no differences between these groups concerning the other hormonal basal levels and after the pharmachological challenges. Conclusion: Our findings provide evidence that there are several changes in hormonal levels related to the functioning of the HPA axis and its receptors GR and MR in depressive patients associated to hypocortisolism and the increase of negative feedback MR- and GR- mediated. Our data also suggest the role of prolactin in the development of depressive disorder with ELS, however, more studies are needed to better highlight the importance of other hormones of HPA axis and its receptors in depressive disorders with ELS
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Meloxicam e prednisona: efeito do tratamento oral de curto prazo nos n?veis de press?o intra-ocular de c?es (Canis familiaris) / Meloxican and prednisone: the effect of orally short term treatment on the intra-ocular pressure levels of dogs (Canis familiaris)Souza, Maria Alice Fusco de 25 August 2006 (has links)
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Previous issue date: 2006-08-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / It is recognized the role of prostaglandins in lowering de intraocular pressure, and more
recently, the observation of constitutive expression of COX-2 in the healthy eyes and the
absence of this isoenzyme in glaucomatous eyes. These discoveries bring the hypothesis that
the use of anti-inflammatory drugs may cause, as unwanted effects, ocular hypertension
through the inhibition of COX expression and the reduction of prostaglandins production. The
increase of intraocular pressure, even in a transient way, is a risk factor for the development
of the glaucoma. In order to observe a possible ocular hypertension associated with the use of
anti-inflammatory drugs, 28 beagle dogs were selected from the kennel of the Laboratory of
Development of Parasiticide Products, Department of Animal Parasitology, Veterinary
Institute, Universidade Federal Rural do Rio de Janeiro. On day 0 (zero) the totality of
animals had their intraocular pressure measured using applanation tonometry at 8 a.m. and 4
p.m., for evaluation of intraocular pressure before treatment; on the following day 10 animals
received meloxican, associated with wet feeding, on dosage of 0.2 mg Kg-1 and 0.1 mg weight
on the remainder of the four days, nine dogs received prednisone, associated with wet feeding,
on dosage of 1,0 mg Kg-1 during five days and nine dogs received only wet feeding. On the
fifth day of treatment the totality of dogs had their intraocular pressure measured again using
applanation tonometry at 8 a.m. and 4 p.m. For all groups, including control-group, the
highest average values of intraocular pressure were observed on day 5 (five). The difference
between intra-ocular pressure mensurations of the 08 hours and of the 16 hours was
significant, independent of treatment and of the considered day. The use of both steroidal or
non-steroidal anti-inflammatory were not capable of causing ocular hypertension and some
factors can be incriminated, such as route of administration, dosage and duration of therapy
chosen, besides genetic inheritance and absence of glaucomatous disorder between the
selected dogs. / ? reconhecido o papel hipotensor ocular das prostaglandinas e mais recentemente, a
observa??o da express?o de COX-2 constitutiva em olhos saud?veis e aus?ncia desta
isoenzima em olhos glaucomatosos. Estas descobertas geram a hip?tese de que o uso de
antiinflamat?rios apresente como efeito colateral, a hipertens?o ocular pela inibi??o da
express?o da COX e diminui??o da produ??o de prostaglandinas. O aumento de press?o
intra-ocular, mesmo que transit?rio, ? um fator de risco para o desenvolvimento do glaucoma.
Para poss?vel observa??o da hipertens?o ocular com o uso de antiinflamat?rios, foram
selecionados 28 c?es da ra?a beagle pertencentes ao Canil do Laborat?rio de
Desenvolvimento de Produtos Parasiticidas do Departamento de Parasitologia Animal do
Instituto de Veterin?ria da Universidade Federal Rural do Rio de Janeiro. No dia 0 (zero)
todos os animais tiveram a press?o intra-ocular mensurada com o uso do ton?metro de
aplana??o ?s 08 horas e ?s 16 horas, para avalia??o da press?o intra-ocular antes do
tratamento; no dia seguinte dez c?es receberam meloxicam, junto ? por??o de ra??o ?mida, na
dosagem de 0,2 mg/Kg e 0,1mg/Kg nos restantes quatro dias, nove c?es receberam
prednisona, junto ? por??o de ra??o ?mida, na dosagem de 1,0 mg/Kg durante cinco dias e
nove c?es receberam somente a por??o de ra??o ?mida. No quinto dia do tratamento todos os
animais tiveram novamente a press?o intra-ocular mensurada com o uso do ton?metro de
aplana??o ?s 08 horas e ?s 16 horas. Em todos os grupos, incluindo o grupo-controle, as
maiores m?dias de press?o intra-ocular foram observadas no dia 5 (cinco). A diferen?a dos
valores de press?o intra-ocular observada entre as medi??es das 08 horas e das 16 horas foi
significativa, independente do tratamento e do dia considerado. O uso dos antiinflamat?rios
esteroidal e n?o-esteroidal n?o foi capaz de causar hipertens?o ocular e alguns fatores podem
ser incriminados, como via de administra??o, dosagem e dura??o do tratamento utiliz ados,
al?m da heran?a gen?tica e aus?ncia de doen?a glaucomatosa nos c?es selecionados.
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“CpdX”, a non-steroidal Selective Glucocorticoid Receptor Agonistic Modulator (SEGRAM) selectively triggers the beneficial anti-inflammatory activity of glucocorticoids, but not their long-term debilitating effects / Caractérisation de ligands non-stéroïdiens du récepteur des glucocorticoïdes dotés d’activités anti-inflammatoires bénéfiques, mais dépourvus des effets secondaires indésirables des glucocorticoïdes de synthèseZein, Naïmah 14 December 2018 (has links)
Lors de la liaison d’un glucocorticoïde (GC) naturel ou synthétique (par exemple, la Dexaméthasone) au récepteur des glucocorticoïdes (GR), les GCs régulent l’expression de gènes cibles soit par (i) transactivation par liaison ‘’directe’’ à un élément de liaison à l’ADN de type ‘’(+)GRE’’, (ii) transrépression ‘’directe’’ par liaison à un élément de type ‘’nGRE’’ ou (iii) transrépression ‘’indirecte’’ par interaction physique directe avec des facteurs de transcription pro-inflammatoires tels que AP-1 et NF-κB. Les effets anti-inflammatoires bénéfiques des GCs sont généralement attribués à la transrépression indirecte, alors que nombre de leurs effets secondaires pathologiques indésirables paraissent liés à la transactivation et/ou à la transrépression directe. Notre laboratoire a récemment découvert qu’un composé non-stéroïdien dénommé CpdX ainsi que ses dérivés deutérés, ne présentent ni la fonction de transactivation, ni celle de transrépression directe du GR, tout en stimulant son activité bénéfique de transrépression indirecte. Notre projet a consisté à caractériser un composé non-stéroïdien dit CpdX, ainsi que ses dérivés, quant à leurs activités thérapeutiques et à démontrer qu’elles sont semblables à celles des glucocorticoïdes anti-inflammatoires, couramment utilisés, tout en étant débarrassés de leurs effets pathologiques secondaires, tels que l’ostéoporose, l’atrophie cutanée et le syndrome métabolique. Pour atteindre nos objectifs, nous avons utilisés des modèles de souris présentant soit les affections cutanées (dermatites de contact ou atopique, psoriasis), l'asthme, l’arthrite rhumatismale, la colite ulcérative ou la conjonctivite allergique, associés à des études d’immunologie et de biologie moléculaire et cellulaire. Mon travail de thèse a démontré que CpdX, et certains de ses dérivés deutérés, présentent une activité anti-inflammatoire dans le traitement de ces modèles ‘’souris’’ (Partie I). Nous avons aussi montré que le traitement par CpdX et ses dérivés n’induit pas les effets secondaires pathologiques des glucocorticoïdes (Partie II), ouvrait ainsi la vue à une nouvelle ère dans le traitement à long-terme de maladies inflammatoires, sans provoquer les effets pathologiques indésirables des traitements actuels aux glucocorticoïdes. / Upon binding of natural or synthetic glucocorticoids (GCs) (e.g. Dexamethasone) to their glucocorticoid receptor (GR), GCs regulate the expression of target genes either by (i) direct transactivation through direct binding to “(+)GRE” DNA binding sites (DBS), (ii) direct transrepression through binding to “IR nGRE” DBSs or (iii) tethered indirect transrepression mediated through interaction with transactivators, such as NFkB, AP1, or STAT3 bound to their cognate DBSs. The beneficial anti-inflammatory effects of GCs have been generally ascribed to tethered transrepression, whereas many of their long-term undesirable side-effects could be due to transactivation and/or direct transrepression. Our laboratory recently reported that a non-steroidal compound, named CpdX, selectively lacks both direct transactivation and direct transrepression functions, while still exerting an indirect transrepression activity. The goal of our project was to characterize CpdX and some of its derivatives as effective anti-inflammatory drugs similar to glucocorticoids, but lacking their main deleterious side-effects, e.g. osteoporosis, skin atrophy and metabolic disorders. To this end, we have used experimental mouse model for skin disorders (atopic dermatitis, contact dermatitis, and psoriasis), asthma, rheumatoid arthritis, ulcerative colitis and allergic conjunctivitis, combined with immunology, molecular and cellular biology. My thesis studies have demonstrated that in mouse models, CpdX and its derivatives exhibit anti-inflammatory activities, which are similar to those of glucocorticoids (Part I). Importantly, we further show that CpdX and its derivatives do not exhibit the long-term debilitating side-effects of glucocorticoids (Part II). Thereby paving the way to a new era in the long-term therapy of major inflammatory diseases.
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The Round Window Membrane - Gateway to the Cochlea : A Morphological and Electrophysiological studyNordang, Leif January 2002 (has links)
<p>Topical treatment of several inner ear diseases through the round window membrane (RWM) might be feasible in the near future. Bacteria toxins, ototoxic drugs and noise trauma seem to harm the inner ear by a common pathway which involves, excessive outflow of the afferent neurotransmitter glutamate and formation of nitric oxide (NO), which can severely damage cells/nerve endings and lead to cell death.</p><p>In this study we used 98 Sprague-Dawley rats and seven human temporal bones. Various substances were instilled into the middle ear of the rat, such as Pseudomonas Aeruginosa Exotoxin (PaExoA), gentamicin, NO-inhibitor N-Omega-Nitro-L-Arginine Methyl Ester (L-NAME), and glucocorticoids. The effects of the substances were studied by morphological analysis of RWM and the endolymphatic sac (ES) by light and electron microscopic. Hearing level was measured in the rats by ABR technique. The human temporal bones were studied immunomorphologically to search for glutamate.</p><p>In the human inner ear, glutamate receptors and glutamine synthetase, were identified. In the rat, we found, following PaExoA exposure, reversible and permanent hearing loss and morphological changes in the RWM. The ES showed increased numbers of macrophages and thickening of the epithelia. When L-NAME was used as an otoprotector from gentamicin ototoxicity a therapeutic effect in the high frequency area was found. Hydrocortisone (but not dexamethasone) exposure of the RWM resulted in membrane thickening, and adjacent to the membrane, inflammatory cells.</p><p>The importance of the RWM as a portal for toxic substances and topical treatment of inner ear diseases was highlighted in this study. The difficulties of applying drugs in the round window niche were exposed. The results of this study add important knowledge concerning certain mechanisms of inner ear injury and help us to understand possibilities and problems of local treatment of inner ear diseases in patients.</p>
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Intra-articular Glucocorticoid Treatment : Efficacy and Side EffectsWeitoft, Tomas January 2005 (has links)
<p>Intra-articular glucocorticoid injection therapy is frequently used to relieve symptoms of arthritis, but there is considerable variation in injection routines among physicians. One issue of debate concerns the importance of synovial fluid aspiration during the injection procedure. In the present randomised controlled study of patients with rheumatoid arthritis (RA), a significantly reduced risk for arthritis relapse was observed when arthrocentesis was included in the intra-articular injection procedure of the knee. </p><p>Furthermore, there is no consensus about the post-injection regimes. Previous studies have shown beneficial effects of post-injection rest of the knee, but also injection routines for other joints often include such recommendations. The present randomised controlled trial showed that 48-hour rest in elastic orthosis after intra-articular injection in the wrist did not improve the outcome. Thus, the effect of post-injection rest varies between different joints. </p><p>The improved treatment result of post-injection rest of the knee is supposed to be caused by retarded steroid resorption from the joint. In order examine the metabolic effects in cartilage, bone and the hypothalamic-piuitary-adrenal (HPA)-axis, resting and mobile RA patients were studied after intra-articular knee injections. Serum levels of the injected glucocorticoid, triamcinolone hexacetonide (THA), were analysed, as well as cartilage oligomeric matrix protein (COMP) as a marker of cartilage turnover, osteocalcin for bone formation and deoxypyridinoline for bone resorption. The HPA-axis was assessed using serum levels of cortisol and adrenocorticotropine hormone. The result showed a short term and reversible suppression of the HPA-axis and bone formation, whereas bone resorption was unaffected. No differences between mobile and resting patients were observed. In both groups reduction of COMP levels were seen, but these were significantly more pronounced in resting patients, suggesting a cartilage-protective effect. The THA levels increased similarly in both groups, indicating that rest did not affect glucocorticoid resorption. </p><p>Consequently, another explanation for the beneficial effects of postinjection rest of knee synovitis should be considered. In the present material the incidence of infectious complications of intra-articular treatment was less than 1/12,000 injections. </p><p>The findings in this thesis can be applied in the clinical practice and should be considered when new guidelines for intra-articular glucocorticoid therapy are created.</p>
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The Round Window Membrane - Gateway to the Cochlea : A Morphological and Electrophysiological studyNordang, Leif January 2002 (has links)
Topical treatment of several inner ear diseases through the round window membrane (RWM) might be feasible in the near future. Bacteria toxins, ototoxic drugs and noise trauma seem to harm the inner ear by a common pathway which involves, excessive outflow of the afferent neurotransmitter glutamate and formation of nitric oxide (NO), which can severely damage cells/nerve endings and lead to cell death. In this study we used 98 Sprague-Dawley rats and seven human temporal bones. Various substances were instilled into the middle ear of the rat, such as Pseudomonas Aeruginosa Exotoxin (PaExoA), gentamicin, NO-inhibitor N-Omega-Nitro-L-Arginine Methyl Ester (L-NAME), and glucocorticoids. The effects of the substances were studied by morphological analysis of RWM and the endolymphatic sac (ES) by light and electron microscopic. Hearing level was measured in the rats by ABR technique. The human temporal bones were studied immunomorphologically to search for glutamate. In the human inner ear, glutamate receptors and glutamine synthetase, were identified. In the rat, we found, following PaExoA exposure, reversible and permanent hearing loss and morphological changes in the RWM. The ES showed increased numbers of macrophages and thickening of the epithelia. When L-NAME was used as an otoprotector from gentamicin ototoxicity a therapeutic effect in the high frequency area was found. Hydrocortisone (but not dexamethasone) exposure of the RWM resulted in membrane thickening, and adjacent to the membrane, inflammatory cells. The importance of the RWM as a portal for toxic substances and topical treatment of inner ear diseases was highlighted in this study. The difficulties of applying drugs in the round window niche were exposed. The results of this study add important knowledge concerning certain mechanisms of inner ear injury and help us to understand possibilities and problems of local treatment of inner ear diseases in patients.
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Intra-articular Glucocorticoid Treatment : Efficacy and Side EffectsWeitoft, Tomas January 2005 (has links)
Intra-articular glucocorticoid injection therapy is frequently used to relieve symptoms of arthritis, but there is considerable variation in injection routines among physicians. One issue of debate concerns the importance of synovial fluid aspiration during the injection procedure. In the present randomised controlled study of patients with rheumatoid arthritis (RA), a significantly reduced risk for arthritis relapse was observed when arthrocentesis was included in the intra-articular injection procedure of the knee. Furthermore, there is no consensus about the post-injection regimes. Previous studies have shown beneficial effects of post-injection rest of the knee, but also injection routines for other joints often include such recommendations. The present randomised controlled trial showed that 48-hour rest in elastic orthosis after intra-articular injection in the wrist did not improve the outcome. Thus, the effect of post-injection rest varies between different joints. The improved treatment result of post-injection rest of the knee is supposed to be caused by retarded steroid resorption from the joint. In order examine the metabolic effects in cartilage, bone and the hypothalamic-piuitary-adrenal (HPA)-axis, resting and mobile RA patients were studied after intra-articular knee injections. Serum levels of the injected glucocorticoid, triamcinolone hexacetonide (THA), were analysed, as well as cartilage oligomeric matrix protein (COMP) as a marker of cartilage turnover, osteocalcin for bone formation and deoxypyridinoline for bone resorption. The HPA-axis was assessed using serum levels of cortisol and adrenocorticotropine hormone. The result showed a short term and reversible suppression of the HPA-axis and bone formation, whereas bone resorption was unaffected. No differences between mobile and resting patients were observed. In both groups reduction of COMP levels were seen, but these were significantly more pronounced in resting patients, suggesting a cartilage-protective effect. The THA levels increased similarly in both groups, indicating that rest did not affect glucocorticoid resorption. Consequently, another explanation for the beneficial effects of postinjection rest of knee synovitis should be considered. In the present material the incidence of infectious complications of intra-articular treatment was less than 1/12,000 injections. The findings in this thesis can be applied in the clinical practice and should be considered when new guidelines for intra-articular glucocorticoid therapy are created.
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