RESUMO
Recent evidence has suggested that inflammatory and immune mechanisms may play a role in the pathophysiology of bipolar disorder (BD). Only a few studies have assessed the profile of chemokines, a family of chemotactic cytokines related to the recruitment of leukocytes, in BD. The objective of our study was to evaluate the plasma levels of chemokines in BD patients in different mood states in comparison with healthy controls. Seventy BD type I patients (35 in euthymia and 35 in mania), and 50 healthy controls matched by age, gender, and education level were enrolled in this study. All subjects were assessed by the Mini-International Neuropsychiatry Interview and the patients by the Young Mania Rating Scale and the Hamilton Depression Rating Scale. The plasma levels of CCL2, CCL3, CCL11, CCL24, CXCL8, and CXCL10 were measured by enzyme-linked immunosorbent assay. BD patients presented higher plasma levels of CCL11 (1.69-fold increase; p < 0.001), CCL24 (1.40-fold increase; p = 0.02), CXCL10 (1.45-fold increase; p < 0.001) and decreased plasma levels of CXCL8 (8.68-fold decrease p < 0.001). Logistic regression stressed the main effect of increased plasma levels of CXCL10 (OR = 1.009, 95 % CI = 1.000-1.018, p = 0.042) and CCL11 (OR = 1.002, 95 % CI = 1.001-1.003, p = 0.003) and decreased plasma levels of CXCL8 (OR = 0.995, 95 % CI = 0.990-0.999, p = 0.013) to BD. This study reinforces the view that BD is associated with an immune dysfunction.
Assuntos
Transtorno Bipolar/imunologia , Quimiocinas/imunologia , Inflamação/imunologia , Adulto , Afeto/fisiologia , Estudos de Casos e Controles , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Despite the old Kraepelinean concept that bipolar disorder (BD) does not evolve with cognitive decline, the presence of cognitive impairment, especially executive dysfunction has been recognized in BD patients. Brain-derived neurotrophic factor (BDNF) and pro-inflammatory molecules are important contributors to the pathophysiology of BD, and imbalance in peripheral levels of these molecules may be implicated in the cognitive decline observed in BD patients. We aimed to investigate the executive performance of BD type I euthymic patients and its relation with the plasma levels of BDNF, TNF-α and its related soluble receptors (sTNFR1 and sTNFR2). METHODS: We evaluated executive functioning through the Frontal Assessment Battery (FAB). Plasma levels of BDNF, TNF-α, sTNFR1 and sTNFR2 were measured using enzyme-linked immunosorbent assay (ELISA) in 25 euthymic type I BD patients and 25 age and gender matched healthy controls. RESULTS: BD patients had an impairment in executive functioning (p<0.006), particularly sensitivity of interference (p=0.02), inhibitory control (p=0.02), and increased BDNF plasma levels (p=0.001) in comparison with controls. Plasma levels of TNF-α were correlated with inhibitory control in BD patients (ρ=0.50, p=0.02) while motor programming was negatively correlated with sTNFR2 plasma levels (ρ=-0.47, p=0.02) in controls. Executive function correlated with age and MMSE, but not with BDNF, neither was influenced by psychiatric and clinical comorbidities nor medications in use. CONCLUSION: BDNF is altered in BD but do not correlate with executive functioning.
Assuntos
Transtorno Bipolar/sangue , Transtorno Bipolar/psicologia , Fator Neurotrófico Derivado do Encéfalo/sangue , Função Executiva , Fator de Necrose Tumoral alfa/sangue , Adulto , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptores Tipo I de Fatores de Necrose Tumoral/sangue , Receptores Tipo II do Fator de Necrose Tumoral/sangueRESUMO
OBJECTIVE: To review the new findings about stress, hypothalamic-pituitary-adrenal axis and depression trying to explain a possible endophenotype prone to depression. METHOD: Nonsystematic review of the literature based on the endophenotype hypothesis. RESULTS: Depression is linked to hypercortisolemia in many patients, but not all patients present these hypothalamic-pituitary-adrenal axis dysfunction. The dexamethasone suppression test is not the most accurate test to measure the hypothalamic-pituitary-adrenal axis function, and its use in the first studies published probably jeopardized the results. Hypercortisolemia frequently occurs in patients with severe depression, melancholic, either psychotic or nonpsychotic type; it is linked to the presence of a polymorphism in the promoter of the serotonin transporter gene, with a history of childhood abuse or neglect, or other significant stressful experiences like the loss of a parent during childhood and temperament leading to alterations in the response to stress. CONCLUSIONS: The alterations of the hypothalamic-pituitary-adrenal axis depend on many factors like severity and type of depression, genotype, history of exposure to stress, temperament, and probably resilience. All these factors together result in an endophenotype thought to be prone to depression.
Assuntos
Transtorno Depressivo Maior/genética , Glucocorticoides/metabolismo , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Estresse Psicológico/genética , Hormônio Adrenocorticotrópico/metabolismo , Hormônio Liberador da Corticotropina , Transtorno Depressivo Maior/fisiopatologia , Dexametasona , Predisposição Genética para Doença , Humanos , Fenótipo , Polimorfismo Genético , Estresse Psicológico/fisiopatologia , TemperamentoRESUMO
OBJETIVO: Revisar os achados recentes sobre a relação entre estresse, eixo hipotálamo-pituitária-adrenal e depressão, na tentativa de explicar um endofenótipo de vulnerabilidade para o desenvolvimento da depressão. MÉTODO: Revisão não sistemática da literatura baseada na hipótese de endofenótipo. RESULTADOS: A depressão está relacionada à hipercortisolemia em muitos pacientes; porém, nem todos os deprimidos apresentam esta alteração na função hipotálamo-pituitária-adrenal. Os primeiros estudos publicados observaram esta hiperativação do eixo hipotálamo-pituitária-adrenal por meio do teste de supressão da dexametasona. Estes resultados não foram largamente replicados em grande parte devido à falta de acurácia desse teste. A hipercortisolemia ocorre freqüentemente em pacientes com depressão grave, do tipo melancólico, psicóticos ou não. Está relacionada a um polimorfismo específico do gene do transportador da serotonina; a história de abuso ou negligência durante a infância ou perda parental precoce; e ao temperamento que resulta em alterações na resposta ao estresse. CONCLUSÕES: As alterações do eixo hipotálamo-pituitária-adrenal dependem de diversos fatores, como gravidade e tipo de depressão, genótipo, história de trauma na infância, temperamento e, provavelmente, resiliência. Todas essas variáveis se relacionam a um endofenótipo vulnerável ao desenvolvimento de depressão.
OBJECTIVE: To review the new findings about stress, hypothalamic-pituitary-adrenal axis and depression trying to explain a possible endophenotype prone to depression. METHOD: Nonsystematic review of the literature based on the endophenotype hypothesis. RESULTS: Depression is linked to hypercortisolemia in many patients, but not all patients present these hypothalamic-pituitary-adrenal axis dysfunction. The dexamethasone suppression test is not the most accurate test to measure the hypothalamic-pituitary-adrenal axis function, and its use in the first studies published probably jeopardized the results. Hypercortisolemia frequently occurs in patients with severe depression, melancholic, either psychotic or nonpsychotic type; it is linked to the presence of a polymorphism in the promoter of the serotonin transporter gene, with a history of childhood abuse or neglect, or other significant stressful experiences like the loss of a parent during childhood and temperament leading to alterations in the response to stress. CONCLUSIONS: The alterations of the hypothalamic-pituitary-adrenal axis depend on many factors like severity and type of depression, genotype, history of exposure to stress, temperament, and probably resilience. All these factors together result in an endophenotype thought to be prone to depression.
Assuntos
Humanos , Transtorno Depressivo Maior/genética , Glucocorticoides/metabolismo , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Estresse Psicológico/genética , Hormônio Adrenocorticotrópico/metabolismo , Hormônio Liberador da Corticotropina , Transtorno Depressivo Maior/fisiopatologia , Dexametasona , Predisposição Genética para Doença , Fenótipo , Polimorfismo Genético , Estresse Psicológico/fisiopatologia , TemperamentoRESUMO
Subjects at their first psychotic episode show an enlarged volume of the pituitary gland, but whether this is due to hypothalamicpituitaryadrenal (HPA) axis hyperactivity, or to stimulation of the prolactin-secreting cells by antipsychotic treatment, is unclear. We measured pituitary volume, using 1.5-mm, coronal, 1.5 T, high-resolution MRI images, in 78 patients at the first psychotic episode and 78age- and gender-matched healthy controls. In all, 18 patients were antipsychotic-free (12 of these were antipsychotic-naý¨ve), 26 werereceiving atypical antipsychotics, and 33 were receiving typical antipsychotics. As hypothesized, patients had a larger pituitary volume than controls (+22percent , p=0.001). When divided by antipsychotic treatment, and compared to controls, the pituitary volume was 15 percent larger in antipsychotic-free patients (p¼0.028), 17 percent larger in patients receiving atypicals (p¼0.01), and 30 percent larger in patients receiving typicals (p=0.001). Patients receiving typicals not only had the largest pituitary volume compared to controls but also showed a trend for a larger pituitary volume compared to the other patients grouped together (11 percent, p¼0.08). When divided by diagnosis, and compared to controls, the pituitary volume was 24 percent larger in patients with schizophrenia/schizophreniform disorder (n¼40, p=0.001), 19 percent larger in depressed patients (n¼13, p¼0.022), 16 percent larger in bipolar patients (n¼16, p¼0.037), and 12 percent larger in those with other psychoses (n¼9, p¼0.2). In conclusion, the first-episode of a psychotic disorder is associated with a larger pituitary independently of the presenceof antipsychotic treatment, and this could be due to activation of the HPA axis. Typical antipsychotics exert an additional enlarging effecton pituitary volume, likely to be related to activation of prolactin-secreting cells...
Assuntos
Humanos , Hipotálamo , Hipófise , Glândulas Suprarrenais , Esquizofrenia , Estresse Fisiológico , Transtornos do HumorRESUMO
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.
Assuntos
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.
Assuntos
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.