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Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis represents one of the most consistent pathophysiological findings in depressive disorders. Cortisol signaling is affected by proteins that mediate its cellular responses or alters its availability to mineralocorticoid and glucocorticoid receptors. In our study, we evaluated candidate genes that may influence the risk for depression and suicide due to its involvement in cortisol signaling. The aim of the study was to assess whether the genotypes of these genes are associated with the risk for depression, severity of depressive symptoms, suicidal ideation, and suicide attempts. And whether there is interaction between genes and early-life stress. In this study, 100 healthy controls and 140 individuals with depression were included. The subjects were clinically assessed using the 21-item GRID-Hamilton questionnaires (GRID-HAMD-21), Beck Scale for Suicidal Ideation (BSI), and the Childhood Trauma Questionnaire (CTQ). A robust multifactorial dimensionality reduction analysis was used to characterize the interactions between the genes HSD11B1, NR3C1, NR3C2, and MDR1 and early-life stress. It was found a significant association of the heterozygous genotype of the MDR1 gene rs1128503 polymorphism with reduced risk of at least one suicide attempt (OR: 0.08, p = 0.003*) and a reduction in the number of suicide attempts (ß = -0.79, p = 0.006*). Furthermore, it was found that the MDR1 rs1228503 and NR3C2 rs2070951 genes interact with early-life stress resulting in a strong association with depression (p = 0.001). Our findings suggest that polymorphisms in the MDR1 and NR3C2 genes and their interaction with childhood trauma may be important biomarkers for depression and suicidal behaviors.
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Epistasia Genética , Hidrocortisona , Receptores de Glucocorticoides , Receptores de Mineralocorticoides , Ideação Suicida , Tentativa de Suicídio , Humanos , Feminino , Masculino , Adulto , Receptores de Glucocorticoides/genética , Hidrocortisona/metabolismo , Receptores de Mineralocorticoides/genética , Experiências Adversas da Infância , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Depressão/genética , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Adulto Jovem , Estresse Psicológico/genética , Predisposição Genética para DoençaRESUMO
BACKGROUND: Sexual assault is implicated in several adverse psychological and physical health outcomes, including posttraumatic stress disorder (PTSD) and depression. Neurobiological research has shown variations related to the hypothalamic-pituitary-adrenal (HPA) axis, immune alterations, metabolic function, and brain circuitry. Although these mechanisms have been extensively studied, the results have demonstrated different outcomes in PTSD. METHODS: We compared the plasma adrenocorticotropin (ACTH) and salivary cortisol levels of fifty-eight women with PTSD developed after sexual assault to those of forty-four female controls with no history of trauma. We also evaluated the psychiatric diagnosis and symptom severity of PTSD and depression. The participants' clinical conditions were associated with their hormonal levels to assess whether symptom severity was related to hormonal imbalance. RESULTS: A large percentage of sexually assaulted women had PTSD and comorbid depression. The ACTH levels were higher in the PTSD group than the control group and increased as PTSD severity increased, considering depressive symptoms, measured by the Beck Depression Inventory (BDI) (p < 0.0001), as well as PTSD symptoms, measured by subscale D of the Clinician-Administered PTSD Scale (CAPS-5) (p = 0.045) and the CAPS-5 total scale (p = 0.026). Cortisol levels measured at 10 pm were higher for the PTSD group than the control group (p = 0.045, p = 0.037, respectively), and the cortisol awakening response showed elevated cortisol levels for the PTSD group. CONCLUSIONS: These results show a correlation between symptom severity and HPA axis imbalance in patients with PTSD. Elevated ACTH and an elevated cortisol response in patients with comorbid depressive symptoms were the opposite of the expected response for patients with PTSD only. This association leads to the hypothesis that the neurobiological alterations of PTSD are related to the type of symptoms presented and their severity. These manifestations likely influence the disease course, prognosis and response to treatment. These outcomes highlight the need to discuss particular neurobiological alterations in patients with PTSD developed after sexual assault, mainly those with severe depressive symptoms.
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Sistema Hipotálamo-Hipofisário , Transtornos de Estresse Pós-Traumáticos , Depressão/complicações , Feminino , Humanos , Hidrocortisona , Sistema Hipófise-Suprarrenal , Transtornos de Estresse Pós-Traumáticos/complicaçõesRESUMO
Ayahuasca is a South American psychoactive plant brew used as traditional medicine in spiritual and in cultural rituals. This is a review of the current understanding about the pharmacological mechanisms that may be interacting in ayahuasca. Searches were performed using PubMed, PsycINFO, and Web of Science databases and 16 papers were selected. As hypothesized, the primary narrative in existing research revolved around prevention of deamination of N,N-dimethyltryptamine (N,N-DMT, also referred to as DMT) by monoamine oxidase inhibitors (MAOIs) in ayahuasca. Two of the constituents, DMT and harmine, have been studied more than the secondary harmala alkaloids. At present, it is unclear whether the pharmacological interactions in ayahuasca act synergistically or additively to produce psychoactive drug effects. The included studies suggest that our current understanding of the preparation's synergistic mechanisms is limited and that more complex processes may be involved; there is not yet enough data to determine any potential synergistic interaction between the known compounds in ayahuasca. Our pharmacological understanding of its compounds must be increased to avoid the potential risks of ayahuasca use.
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Humanos , Banisteriopsis , Psicotrópicos/farmacologia , Extratos Vegetais/farmacologia , N,N-Dimetiltriptamina/farmacologia , Harmina/farmacologiaRESUMO
Ayahuasca is a South American psychoactive plant brew used as traditional medicine in spiritual and in cultural rituals. This is a review of the current understanding about the pharmacological mechanisms that may be interacting in ayahuasca. Searches were performed using PubMed, PsycINFO, and Web of Science databases and 16 papers were selected. As hypothesized, the primary narrative in existing research revolved around prevention of deamination of N,N-dimethyltryptamine (N,N-DMT, also referred to as DMT) by monoamine oxidase inhibitors (MAOIs) in ayahuasca. Two of the constituents, DMT and harmine, have been studied more than the secondary harmala alkaloids. At present, it is unclear whether the pharmacological interactions in ayahuasca act synergistically or additively to produce psychoactive drug effects. The included studies suggest that our current understanding of the preparation's synergistic mechanisms is limited and that more complex processes may be involved; there is not yet enough data to determine any potential synergistic interaction between the known compounds in ayahuasca. Our pharmacological understanding of its compounds must be increased to avoid the potential risks of ayahuasca use.
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Banisteriopsis , Harmina/farmacologia , Humanos , N,N-Dimetiltriptamina/farmacologia , Extratos Vegetais/farmacologia , Psicotrópicos/farmacologiaRESUMO
The hypothalamic-pituitary-adrenal axis has been implicated in the pathophysiology of depressive disorders. HSD11B1 encodes 11ß-hydroxysteroid dehydrogenase type1 enzyme, responsible for converting cortisone to cortisol. Genetic polymorphisms in HSD11B1 may impact in depression outcome and risk of suicide. This study aimed to assess whether HSD11B1 genotypes and haplotypes are associated with depression risk, severity of symptoms and suicidal attempts, considering early-life stress as an environmental factor. Here, 142 depressive patients and 103 healthy controls were included. Patients were enrolled from the Affective Disorders ambulatory and day hospital units, both within the University General Hospital of Ribeirao Preto. All subjects were clinically assessed applying the Mini-PLUS International Neuropsychiatric Interview, followed by the 21-item GRID-Hamilton Depression Scale, Childhood Trauma Questionnaire and Beck Scale for Suicidal Ideation (BSI). All subjects underwent antecubital vein puncture to obtain blood for DNA extraction. Genotyping of rs11119328 and rs11811440 were performed using allele-specific oligonucleotide polymerase chain reaction. We found a significant association of rs11119328 variant genotypes with increased risk for at least one suicide attempt (OR: 7.10, pâ¯=â¯0.049) and an association of variant genotypes of rs11811440 with euthymic mood under optimized pharmacological treatment (OR: 0.05, Pâ¯=â¯0.014). These tests included correction for confounding factors. The association of genetic markers with depression risk, GRID-HAM-D21 and BSI scores and the number of suicidal attempts were nonsignificant. Haplotypes combining both markers were not associated with the studied phenotypes. We conclude that HSD11B1 polymorphisms may be relevant biomarkers for detecting subjects genetically vulnerable to poorer antidepressant response and higher risk of suicide attempts.
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11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , Antidepressivos/uso terapêutico , Transtorno Depressivo/tratamento farmacológico , Tentativa de Suicídio , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/metabolismo , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Resultado do Tratamento , Adulto JovemRESUMO
INTRODUCTION: Borderline Personality Disorder (BPD) and Bipolar Affective Disorder (BD) have clinical characteristics in common which often make their differential diagnosis difficult. The history of early life stress (ELS) may be a differentiating factor between BPD and BD, as well as its association with clinical manifestations and specific neuroendocrine responses in each of these diagnoses. OBJECTIVE: Assessing and comparing patients with BD and BPD for factors related to symptomatology, etiopathogenesis and neuroendocrine markers. METHODOLOGY: The study sample consisted of 51 women, divided into 3 groups: patients with a clinical diagnosis of BPD (nâ¯=â¯20) and BD (nâ¯=â¯16) and healthy controls (HC, nâ¯=â¯15). Standardized instruments were used for the clinical evaluation, while the history of ELS was quantified with the Childhood Trauma Questionnaire (CTQ), and classified according to the subtypes: emotional abuse, physical abuse, sexual abuse, emotional neglect and physical neglect. The functioning of the hypothalamic-pituitary-adrenal (HPA) axis was evaluated by measuring a single plasma cortisol sample. RESULTS: Patients with BPD presented with more severe psychiatric symptoms of: anxiety, impulsivity, depression, hopelessness and suicidal ideation than those with BD. The history of ELS was identified as significantly more prevalent and more severe in patients (BPD and BP) than in HC. Emotional abuse, emotional neglect and physical neglect also showed differences and were higher in BPD than BD patients. BPD patients had greater severity of ELS overall and in the subtypes of emotional abuse, emotional neglect and physical neglect than BD patients. The presence of ELS in patients with BPD and BP showed significant difference with lower cortisol levels when compared to HC. The endocrine evaluation showed no significant differences between the diagnoses of BPD and BD. Cortisol measured in patients with BPD was significantly lower compared to HC in the presence of emotional neglect and physical neglect. A significant negative correlation between the severity of hopelessness vs cortisol; and physical neglect vs cortisol were found in BPD with ELS. The single cortisol sample showed a significant and opposite correlations in the sexual abuse diagnosis-related groups, being a negative correlation in BD and positive in BPD. DISCUSSION: Considering the need for a multi-factorial analysis, the differential diagnosis between BPD and BD can be facilitated by the study of psychiatric symptoms, which are more severe in the BPD patients with a history of early life stress. The function of the HPA axis assessed by this cortisol measure suggests differences between BPD and BP with ELS history. CONCLUSION: The integrated analysis of psychopathology, ELS and neuroendocrine function may provide useful indicators to differentiate BPD and BD diagnoses. These preliminary data need to be replicated in a more significant sample with improved and multiple assessments of HPA axis activity.
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Transtorno Bipolar/sangue , Transtorno Bipolar/psicologia , Transtorno da Personalidade Borderline/sangue , Transtorno da Personalidade Borderline/psicologia , Hidrocortisona/sangue , Estresse Psicológico/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Psicometria , Adulto JovemRESUMO
Background: Childhood sexual abuse (CSA) is a prevalent subtype of early life stress associated with changes in immunological and neuroendocrine systems leading to inflammatory responses of the organism and increasing several inflammatory and immune markers. We aimed to conduct a systematic review concerning the association between CSA and indicators of immune activity. Methods: We conducted a search for articles in PubMed, Scopus, PsycINFO, and Web of Science, using the key words: ("Child sexual abuse" OR "childhood maltreatment" OR "sexual violence" OR "posttraumatic stress disorder" OR "rape") AND ("cytokines" OR "inflammatory markers" OR "interleukin" OR "tumor necrosis factor" OR "C-reactive protein"). PRISMA guidelines were used in order to improve the quality of this research, and MeSH terms were used in PubMed. Results: A total of 3,583 studies were found and, after application of the exclusion criteria, 17 studies were included in this review. Most studies reported an increase of inflammatory activity associated with the presence of early abuse. IL-6, TNF- α, and C-reactive protein were the most frequently analyzed markers and some studies showed higher levels in individuals that suffered CSA compared with controls, although the results were heterogeneous, as was the assessment of CSA, repeated trauma, and time of occurrence. It was not possible to perform a meta-analysis because the results were diversified. Conclusion: CSA is associated with changes in inflammatory markers levels. Improving the assessment of subtypes of trauma is important to further understand the complex correlations of CSA and its biological consequences such as psychiatric and physical illness in later life.
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BACKGROUND: Dysregulation of HPA axis has been widely described in subjects with bipolar disorder (BD), including changes in cortisol levels during mood episodes and euthymia. However, most of the studies were done with medicated BD patients with variable length of illness, which was shown to interfere on peripheral cortisol levels. Therefore, the present study aims to evaluate plasma cortisol levels in drug-naïve BD subjects during the first manic episode, as well as investigate the relationship between plasma cortisol levels and manic symptomatology. METHODS: Twenty-six drug-naïve patients were enrolled meeting criteria for a first manic episode in bipolar I disorder. Severity of mania was assessed using the Young Mania Rating Scale (YMRS). The control group included 27 healthy subjects matched by age and gender. Cortisol was quantified using a direct radioimmunoassay. RESULTS: Plasma cortisol levels were decreased during first manic episode compared to healthy controls. Higher cortisol levels were positively associated with the presence of irritability (dysphoria), while elated mania showed lower cortisol levels compared to controls. LIMITATION: Data including larger samples are lacking. CONCLUSION: Higher cortisol in dysphoric mania compared to predominantly elated/euphoric mania may indicate a clinical and neurobiological polymorphic phenomenon, potentially involving a higher biological sensitivity to stress in the presence of irritable mood. The present findings highlight the importance to add a dimensional approach to the traditional categorical diagnosis for future neurobiological studies in BD.
Assuntos
Transtorno Bipolar/sangue , Hidrocortisona/sangue , Adulto , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/psicologia , Euforia , Humanos , Humor Irritável , Adulto JovemRESUMO
OBJECTIVE: The mechanisms involved in the dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, especially in the functioning of glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) in depressed patients, are not well elucidated. The objective of this study was to conduct a systematic review of articles that assess the HPA axis activity from GR and MR in depressed patients and healthy controls with or without early life stress. METHODS: We conducted a systematic review of articles in PubMed, SCOPUS and SciELO published between 2000 and 2011, using the following search terms: child abuse, depression, HPA axis, dexamethasone, prednisolone, fludrocortisone and spironolactone. Thirty-four papers were selected for this review. RESULTS: Most studies identified in this review used the dexamethasone/corticotropin-releasing hormone test and dexamethasone suppression test. In these studies, hypercortisolaemia was associated with depression. We identified three studies with the Prednisolone suppression test, only one study with the use of fludrocortisone and one with spironolactone. This review found nine studies that evaluated the HPA axis in individuals with early life stress. CONCLUSIONS: The majority of the studies assessed in this review show that early life stress leads to permanent changes in the HPA axis and may lead to development of depression in adults. The most consistent findings in the literature show increased activity of the HPA axis in depression associated with hypercortisolaemia and reduced inhibitory feedback. These findings suggest that this dysregulation of the HPA axis is partially attributable to an imbalance between GR and MR. Evidences have consistently showed that GR function is impaired in major depression, but few studies have assessed the activity of MR in depression and early life stress.
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OBJECTIVE: Melancholic depression is a lifetime diagnosis, typically with recurrent episodes. Melancholia, a syndrome with a long history and distinctive psychopathological features, is differentiated from major depression by the DSM-IV specifiers and partly described in the International Classification of Diseases - 10th edition. Within the present classification, it is frequently seen in severely ill patients with major depression and bipolar disorder. Nevertheless, it has a distinctive psychopathology and biological homogeneity in clinical experience and laboratory test markers, and it is differentially responsive to specific treatment interventions according to international studies. The objective of this study is to review the literature published by Latin American authors about Melancholia. METHOD: We conducted a systematic search to identify scientific literature published by Latin American authors gathering information relevant to the revision of the classification of mental and behavioral disorders in patients with melancholic depression of the International Classification of Diseases - 10th edition. The review was specifically focused on literature from Brazil and Latin America in order to examine the specific Latin American contribution for the study of melancholia as a distinct entity. RESULTS AND CONCLUSION: Melancholia can be identified as a separate mood disorder with unique psychopathology and psychoneuroendocrinology, worthy of separate attention in the classification systems. We therefore suggest that melancholia be positioned as a distinct, identifiable mood disorder that requires specific treatment.
Assuntos
Transtorno Depressivo/diagnóstico , Classificação Internacional de Doenças , Transtorno Depressivo/classificação , Diagnóstico Diferencial , Manual Diagnóstico e Estatístico de Transtornos Mentais , Humanos , América LatinaRESUMO
PURPOSE: To compare the hippocampal volumes in patients with bipolar disorder (BD) and healthy controls, obtained by applying different segmentation methods (manual, Freesurfer [FS], and FSL). MATERIALS AND METHODS: The study included 27 patients with BD and 40 healthy controls. T1-weighted images in the sagittal plane were acquired on a 3 Tesla (T) MR scanner. Hippocampal volumetry was performed using one manual and two automated methods (FS and FSL). One-way repeated analysis of variance was applied to test the differences in hippocampal volumes using the three segmentation methods. To evaluate the agreement among the three tested volumetric segmentation methods the intraclass correlation coefficients (ICCs) were calculated. RESULTS: Hippocampal volumes obtained from all methods were significantly different (P < 0.05) in BD patients after intracranial volume correction, indicating a reduction in volume, unless from the manual method of the left hippocampal volume. The ICCs of the hippocampal volume between the manual method and FS were 0.846 (right) and 0.859 (left), and between the manual method and FSL were 0.746 (right) and 0.654 (left). CONCLUSION: Both manual and automatic segmentation methods detected reductions in the hippocampal volumes in BD patients. Automated segmentation methods are a robust and reproducible option for assessing hippocampal volume.
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Transtorno Bipolar/patologia , Hipocampo/patologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Automação , Mapeamento Encefálico/métodos , Diagnóstico por Imagem/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Reprodutibilidade dos TestesRESUMO
OBJETIVO: A depressão melancólica é um diagnóstico psiquiátrico de história de vida, geralmente com episódios recorrentes. Melancolia é uma síndrome com longa duração e características específicas de psicopatologia, insuficientemente diferenciada de depressão maior por um especificador no DSM-IV e parcialmente descrito nos critérios da Classificação Internacional de Doenças-10ª Edição. Dentro da classificação atual, é frequentemente vista em pacientes gravemente doentes com depressão e transtorno bipolar. No entanto, a melancolia possui uma homogeneidade psicopatológica e biológica distinta na experiência clínica e nos marcadores de testes laboratoriais, e é diferencialmente sensível às intervenções terapêuticas específicas. O objetivo deste estudo é revisar a literatura de artigos publicados por autores latino-americanos sobre a melancolia. MÉTODO: Realizou-se busca de artigos latino-americanos de informações relevantes para a revisão da Classificação Internacional de Doenças-10ª Edição de transtornos mentais e comportamentais em pacientes com depressão melancólica. Foi avaliada a qualidade do design de todos os estudos e realizada uma revisão abrangente sobre o assunto, com o objetivo de considerar a contribuição latino-americana para inclusão da melancolia como uma entidade distinta na futura Classificação Internacional de Doenças-11ª Edição. RESULTADOS E CONCLUSÃO: Os estudos latino-americanos fundamentam o diagnóstico da melancolia com uma psicopatologia e psiconeuroendocrinologia própria que fundamentam ser reconhecida como um transtorno de humor identificável e merecedor de uma atenção específica nos sistemas de classificação, como um transtorno de humor distinto, identificável e especificamente tratável.
OBJECTIVE: Melancholic depression is a lifetime diagnosis, typically with recurrent episodes. Melancholia, a syndrome with a long history and distinctive psychopathological features, is differentiated from major depression by the DSM-IV specifiers and partly described in the International Classification of Diseases - 10th edition. Within the present classification, it is frequently seen in severely ill patients with major depression and bipolar disorder. Nevertheless, it has a distinctive psychopathology and biological homogeneity in clinical experience and laboratory test markers, and it is differentially responsive to specific treatment interventions according to international studies. The objective of this study is to review the literature published by Latin American authors about Melancholia. METHOD: We conducted a systematic search to identify scientific literature published by Latin American authors gathering information relevant to the revision of the classification of mental and behavioral disorders in patients with melancholic depression of the International Classification of Diseases - 10th edition. The review was specifically focused on literature from Brazil and Latin America in order to examine the specific Latin American contribution for the study of melancholia as a distinct entity. RESULTS AND CONCLUSION: Melancholia can be identified as a separate mood disorder with unique psychopathology and psychoneuroendocrinology, worthy of separate attention in the classification systems. We therefore suggest that melancholia be positioned as a distinct, identifiable mood disorder that requires specific treatment.
Assuntos
Humanos , Transtorno Depressivo/diagnóstico , Classificação Internacional de Doenças , Transtorno Depressivo/classificação , Diagnóstico Diferencial , Manual Diagnóstico e Estatístico de Transtornos Mentais , América LatinaRESUMO
Nowadays, new schizophrenia treatments are more ambitious than ever, aiming not only to improve psychotic symptoms, but also quality of life and social reinsertion. Our objective is to briefly but critically review the diagnosis of schizophrenia, the atypical antipsychotics sertindole's pharmacology, safety and status, and mainly evaluate the effects of sertindole compared with other second generation antipsychotics for people with schizophrenia and schizophrenia-like psychosis. In vitro studies showed that sertindole exerts a potent antagonism at serotonin 5-HT2A, 5-HT2C, dopamine D2, and αl adrenergic receptors. Sertindole offers an alternative treatment option for refractory patients given its good EPS profile, favorable metabolic profile, and comparable efficacy to risperidone. Due to cardiovascular safety concerns, sertindole is available as a second-line choice for patients intolerant to other antipsychotic agents. Further clinical studies, mainly comparisons with other second-generation antipsychotic agents, are needed to define the role of sertindole in the treatment of schizophrenia.
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OBJETIVO: As mudanças no eixo hipotálamo-pituitária-adrenal (HPA) são características da depressão. Devido aos efeitos dos glicocorticóides serem mediados por receptores intracelulares, como os receptores de glicocorticóides (RGs), inúmeros estudos examinaram o número e/ou função dos RGs em pacientes com depressão. MÉTODOS: Os autores fazem uma revisão das evidências científicas dos estudos que têm consistentemente demonstrado que a função dos RGs está prejudicada na depressão maior, em conseqüência da redução da resposta do eixo HPA ao feedback negativo mediado pelos RGs e a um aumento na produção e secreção de HLC em várias regiões cerebrais, sugerindo que esses mecanismos estão envolvidos na etiologia da depressão e no tratamento antidepressivo. RESULTADOS: Esta revisão faz um resumo da literatura atual sobre RG na depressão e sobre o impacto dos antidepressivos nos RGs em estudos clínicos e pré-clínicos, e dá suporte ao conceito de que a sinalização deficiente dos RGs é parte fundamental na fisiopatogenia da depressão, na ausência de evidências claras de redução na expressão dos RGs. Embora os efeitos dos antidepressivos nos hormônios glicocorticóides e seus receptores sejam relevantes para a ação terapêutica dessas drogas, os mecanismos moleculares subjacentes a esses efeitos ainda não estão esclarecidos. Estudos indicam que os antidepressivos têm efeitos diretos nos RGs, levando a uma melhora da função e a um aumento da expressão dos RGs. Nós propomos que, em humanos, os antidepressivos podem inibir os transportadores de esteróides localizados na barreira hemato-liquórica e nos neurônios, como o complexo de resistência a múltiplas drogas glicoproteína-p ("multidrug resistance p-glycoprotein"), e podem aumentar o acesso do cortisol ao cérebro e o feedback negativo mediado por glicocorticoides no eixo HPA. CONCLUSÃO: O aumento da ação do cortisol no cérebro pode ser uma abordagem eficaz para maximizar os efeitos terapêuticos dos antidepressivos. Hipóteses referentes aos mecanismos destes receptores envolvem compostos não esteróides que regulam a função dos RGs via segundos mensageiros. A pesquisa nesta área trará novos entendimentos à fisiopatologia e ao tratamento dos transtornos afetivos, em especial na depressão.
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Humanos , Depressão/fisiopatologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Receptores de Glucocorticoides/fisiologia , Antidepressivos/farmacologia , Química Encefálica/efeitos dos fármacos , Química Encefálica/fisiologia , Depressão/metabolismo , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo , Receptores de Glucocorticoides/efeitos dos fármacosRESUMO
OBJECTIVES: Changes in the hypothalamic-pituitary-adrenocortical (HPA) system are characteristic of depression. Because the effects of glucocorticoids are mediated by intracellular receptors including, most notably, the glucocorticoid receptor (GR), several studies have examined the number and/or function of GRs in depressed patients. METHODS: Review scientific evidences have consistently demonstrated that GR function is impaired in major depression, resulting in reduced GR-mediated negative feedback on the HPA axis and increased production and secretion of CRF in various brain regions postulated to be involved in the causality of depression. RESULTS: This article summarizes the literature on GR in depression and on the impact of antidepressants on the GR in clinical and preclinical studies, and supports the concept that impaired GR signalling is a key mechanism in the pathogenesis of depression, in the absence of clear evidence of decreased GR expression. The data also indicate that antidepressants have direct effects on the GR, leading to enhanced GR function and increased GR expression. Although the effects of antidepressants on glucocorticoid hormones and their receptors are relevant for the therapeutic action of these drugs, the molecular mechanisms underlying these effects are unclear. We propose that antidepressants in humans could inhibit steroid transporters localised on the blood-brain barrier and in neurones, like the multidrug resistance p-glycoprotein, and thus increase the access of cortisol to the brain and the glucocorticoid-mediated negative feedback on the HPA axis. CONCLUSION: Enhanced cortisol action in the brain might prove to be a successful approach to maximise therapeutic antidepressant effects. Hypotheses regarding the mechanism of these receptor changes involve non-steroid compounds that regulate GR function via second messenger pathways. Research in this field will lead to new insights into the pathophysiology and treatment of affective disorders.
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Depressão/fisiopatologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Receptores de Glucocorticoides/fisiologia , Antidepressivos/farmacologia , Química Encefálica/efeitos dos fármacos , Química Encefálica/fisiologia , Depressão/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo , Receptores de Glucocorticoides/efeitos dos fármacosRESUMO
Changes in the hypothalamic-pituitary-adrenocortical (HPA) system are characteristic of depression, and in the majority of these patients these result in HPA axis hyperactivity. This is further supported by the reduced sensitivity to the inhibitory effects of the glucocorticoid, dexamethasone (DEX), on the production of adrenocorticotropic hormone (ACTH) and cortisol, during the DEX suppression test and the DEX-corticotropin-releasing hormone (DEX/CRH) test. Because the effects of glucocorticoids are mediated by intracellular receptors including, most notably, the glucocorticoid receptor (GR), several studies have examined the number and/or function of GRs in depressed patients. These studies have consistently demonstrated that GR function is impaired in major depression, resulting in reduced GR-mediated negative feedback on the HPA axis and increased production and secretion of CRH in various brain regions postulated to be involved in the causality of depression. This article summarizes the literature on GR in depression and on the impact of antidepressants on the GR in clinical and preclinical studies, and supports the concept that impaired GR signaling is a key mechanism in the pathogenesis of depression, in the absence of clear evidence of decreased GR expression. The data also indicate that antidepressants have direct effects on the GR, leading to enhanced GR function and increased GR expression. Hypotheses regarding the mechanism of these receptor changes involve non-steroid compounds that regulate GR function via second messenger pathways, such as cytokines and neurotransmitters. Moreover, we present recent evidence suggesting that membrane steroid transporters such as the multidrug resistance (MDR) p-glycoprotein, which regulate access of glucocorticoids to the brain, could be a fundamental target of antidepressant treatment. Research in this field will lead to new insights into the pathophysiology and treatment of affective disorders.
RESUMO
La frecuencia de alteraciones en el humor y comportamiento fue estudiada usando una versión traducida del Cuestionario de Evaluación del Patrón Estacional enviado por correo a una muestra poblacional(N=3800) de la ciudad de San Pablo(23 grados 39 minutos S). Entre los encuestados(N=750; 20,4 por ciento de la muestra inicial), sólo el 1,2 por ciento no presentó cambios en el humor y comportamiento. La media de los puntajes globales de estacionalidad(variación 0-24) fue de 9+- 4,2. Un "patrón estacional de invierno" y de "verano" fue identificado en el 12,9 por ciento y 5,6 por ciento de los participantes, respectivamente. Aquéllos que mencionaron cambios más graves fueron citados para una entrevista psiquiátrica. 16 de los 29 entrevistados cumplieron los criterios para Trastorno Afectivo Estacional(TAE, DSM-III-R). Los cambios estacionales en el humor y comportamiento descritos fueron semejantes a los mencionados en estudios del hemisferio norte, a pesar de la menor variación del fotoperíodo y de las condiciones climáticas agradables
Assuntos
Transtornos do HumorRESUMO
La frecuencia de alteraciones en el humor y comportamiento fue estudiada usando una versión traducida del Cuestionario de Evaluación del Patrón Estacional enviado por correo a una muestra poblacional(N=3800) de la ciudad de San Pablo(23 grados 39 minutos S). Entre los encuestados(N=750; 20,4 por ciento de la muestra inicial), sólo el 1,2 por ciento no presentó cambios en el humor y comportamiento. La media de los puntajes globales de estacionalidad(variación 0-24) fue de 9+- 4,2. Un "patrón estacional de invierno" y de "verano" fue identificado en el 12,9 por ciento y 5,6 por ciento de los participantes, respectivamente. Aquéllos que mencionaron cambios más graves fueron citados para una entrevista psiquiátrica. 16 de los 29 entrevistados cumplieron los criterios para Trastorno Afectivo Estacional(TAE, DSM-III-R). Los cambios estacionales en el humor y comportamiento descritos fueron semejantes a los mencionados en estudios del hemisferio norte, a pesar de la menor variación del fotoperíodo y de las condiciones climáticas agradables