RESUMO
Glucocorticoids exert antiinflammatory, antiproliferative and immunosupressive effects. Paradoxically they may also enhance inflammation particularly in the nervous system, as shown in Cushing´ syndrome and neurodegenerative disorders of humans and models of human diseases. ."The Wobbler mouse model of amyotrophic lateral sclerosis shows hypercorticoidism and neuroinflammation which subsided by treatment with the glucocorticoid receptor (GR) modulator Dazucorilant (CORT113176). This effect suggests that GR mediates the chronic glucocorticoid unwanted effects. We now tested this hypothesis using a chronic stress model resembling the condition of the Wobbler mouse Male NFR/NFR mice remained as controls or were subjected to a restraining / rotation stress protocol for 3 weeks, with a group of stressed mice receiving CORT113176 also for 3 weeks. We determined the mRNAS or reactive protein for the proinflamatory factors HMGB1, TLR4, NFkB, TNFα, markers of astrogliosis (GFAP, SOX9 and acquaporin 4), of microgliosis (Iba, CD11b, P2RY12 purinergic receptor) as well as serum IL1ß and corticosterone. We showed that chronic stress produced high levels of serum corticosterone and IL1ß, decreased body and spleen weight, produced microgliosis and astrogliosis and increased proinflammatory mediators. In stressed mice, modulation of the GR with CORT113176 reduced Iba + microgliosis, CD11b and P2RY12 mRNAs, immunoreactive HMGB1 + cells, GFAP + astrogliosis, SOX9 and acquaporin expression and TLR4 and NFkB mRNAs vs. stress-only mice. The effects of CORT113176 indicate that glucocorticoids are probably involved in neuroinflammation. Thus, modulation of the GR would become useful to dampen the inflammatory component of neurodegenerative disorders.
Assuntos
Proteína HMGB1 , Isoquinolinas , Doenças Neurodegenerativas , Pirazóis , Masculino , Camundongos , Humanos , Animais , Receptores de Glucocorticoides/metabolismo , Corticosterona , Proteína HMGB1/metabolismo , Doenças Neuroinflamatórias , Gliose/metabolismo , Receptor 4 Toll-Like/metabolismo , Glucocorticoides/farmacologia , Medula Espinal/metabolismo , Doenças Neurodegenerativas/metabolismoRESUMO
AIMS: It has been suggested that people with mental disorders have an elevated risk to acquire severe acute respiratory syndrome coronavirus 2 and to be disproportionally affected by coronavirus disease 19 (COVID-19) once infected. We aimed to analyse the COVID-19 infection rate, course and outcome, including mortality and long COVID, in people with anxiety, depressive, neurodevelopmental, schizophrenia spectrum and substance use disorders relative to control subjects without these disorders. METHODS: This study constitutes a preregistered systematic review and random-effects frequentist and Bayesian meta-analyses. Major databases were searched up until 27 June 2023. RESULTS: Eighty-one original articles were included reporting 304 cross-sectional and prospective effect size estimates (median n per effect-size = 114837) regarding associations of interest. Infection risk was not significantly increased for any mental disorder that we investigated relative to samples of people without these disorders. The course of COVID-19, however, is relatively severe, and long COVID and COVID-19-related hospitalization are more likely in all patient samples that we investigated. The odds of dying from COVID-19 were high in people with most types of mental disorders, except for those with anxiety and neurodevelopmental disorders relative to non-patient samples (pooled ORs range, 1.26-2.57). Bayesian analyses confirmed the findings from the frequentist approach and complemented them with estimates of the strength of evidence. CONCLUSIONS: Once infected, people with pre-existing mental disorders are at an elevated risk for a severe COVID-19 course and outcome, including long COVID and mortality, relative to people without pre-existing mental disorders, despite an infection risk not significantly increased.
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COVID-19 , Transtornos Mentais , Humanos , COVID-19/epidemiologia , Estudos Prospectivos , Síndrome de COVID-19 Pós-Aguda , Teorema de Bayes , Estudos Transversais , Transtornos Mentais/epidemiologiaRESUMO
In concert with neuropeptides and transmitters, the end products of the hypothalamus-pituitary-adrenal (HPA) axis, the glucocorticoid hormones cortisol and corticosterone (CORT), promote resilience: i.e., the ability to cope with threats, adversity, and trauma. To exert this protective action, CORT activates mineralocorticoid receptors (MR) and glucocorticoid receptors (GR) that operate in a complementary manner -as an on/off switch- to coordinate circadian events, stress-coping, and adaptation. The evolutionary older limbic MR facilitates contextual memory retrieval and supports an on-switch in the selection of stress-coping styles at a low cost. The rise in circulating CORT concentration after stress subsequently activates a GR-mediated off-switch underlying recovery of homeostasis by providing the energy for restraining the primary stress reactions and promoting cognitive control over emotional reactivity. GR activation facilitates contextual memory storage of the experience to enable future stress-coping. Such complementary MR-GR-mediated actions involve rapid non-genomic and slower gene-mediated mechanisms; they are time-dependent, conditional, and sexually dimorphic, and depend on genetic background and prior experience. If coping fails, GR activation impairs cognitive control and promotes emotional arousal which eventually may compromise resilience. Such breakdown of resilience involves a transition to a chronic stress construct, where information processing is crashed; it leads to an imbalanced MR-GR switch and hence increased vulnerability. Novel MR-GR modulators are becoming available that may reset a dysregulated stress response system to reinstate the cognitive flexibility required for resilience.
RESUMO
Social defeat activates midbrain cells, promoting sleep and reducing anxiety in mice.
Assuntos
Ansiedade , Mesencéfalo , Sono , Derrota Social , Estresse Psicológico , Animais , Ansiedade/fisiopatologia , Mesencéfalo/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Estresse Psicológico/fisiopatologiaRESUMO
The acquired immobility response during the "forced swim test (FST)" is not a rodent model of depression, but the test has some validity in predicting a compound's antidepressant potential. Nevertheless, 60% of the about 600 papers that were published annually the past 2 years label the rodent's immobility response as depression-like behaviour, but the relative contribution per country is changing. When the Editors-in-Chief of 5 journals publishing most FST papers were asked for their point of view on labelling immobility as depression-like behaviour and despair, they responded that they primarily rely on the reviewers regarding scientific merit of the submission. One Editor informs authors of the recent NIMH notice (https://grants.nih.gov/grants/guide/notice-files/NOT-MH-19-053.html) which encourages investigators to use animal models "for" addressing neurobiological questions rather than as model "of" specific mental disorders. The neurobiological questions raised by use of the FST fall in two categories. First, research on the role of endocrine and metabolic factors, with roots in the 1980s, and with focus on the bottom-up action of glucocorticoids on circuits processing salient information, executive control and memory consolidation. Second, recent findings using novel technological and computational advances that have allowed great progress in charting top-down control in the switch from active to passive coping with the inescapable stressor executed by neuronal ensembles of the medial prefrontal cortex via the peri-aquaductal grey. It is expected that combining neural top-down and endocrine bottom-up approaches will provide new insights in the role of stress-coping and adaptation in pathogenesis of mental disorders.
Assuntos
Depressão , Estresse Psicológico , Adaptação Psicológica , Animais , Comportamento Animal/fisiologia , Modelos Animais de Doenças , Humanos , Estresse Psicológico/metabolismo , NataçãoRESUMO
Mitochondrial dysfunction was highlighted as a crucial vulnerability factor for the development of depression. However, systemic studies assessing stress-induced changes in mitochondria-associated genes in brain regions relevant to depression symptomatology remain scarce. Here, we performed a genome-wide transcriptomic study to examine mitochondrial gene expression in the prefrontal cortex (PFC) and nucleus accumbens (NAc) of mice exposed to multimodal chronic restraint stress. We identified mitochondria-associated gene pathways as most prominently affected in the PFC and with lesser significance in the NAc. A more detailed mitochondrial gene expression analysis revealed that in particular mitochondrial DNA-encoded subunits of the oxidative phosphorylation complexes were altered in the PFC. The comparison of our data with a reanalyzed transcriptome data set of chronic variable stress mice and major depression disorder subjects showed that the changes in mitochondrial DNA-encoded genes are a feature generalizing to other chronic stress-protocols as well and might have translational relevance. Finally, we provide evidence for changes in mitochondrial outputs in the PFC following chronic stress that are indicative of mitochondrial dysfunction. Collectively, our work reinforces the idea that changes in mitochondrial gene expression are key players in the prefrontal adaptations observed in individuals with high behavioral susceptibility and resilience to chronic stress.
Assuntos
Suscetibilidade a Doenças/metabolismo , Mitocôndrias/metabolismo , Córtex Pré-Frontal/metabolismo , Estresse Psicológico/metabolismo , Animais , Perfilação da Expressão Gênica , Hormônio Liberador de Gonadotropina/análogos & derivados , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias/genética , Núcleo Accumbens/metabolismo , Núcleo Accumbens/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Resiliência Psicológica , Transcriptoma/fisiologiaRESUMO
Glucocorticoids are crucial for stress-coping, resilience, and adaptation. However, if the stress hormones become dysregulated, the vulnerability to stress-related diseases is enhanced. In this brief review, we discuss the role of glucocorticoids in the pathogenesis of neurodegenerative disorders in both human and animal models, and focus in particular on amyotrophic lateral sclerosis (ALS). For this purpose, we used the Wobbler animal model, which mimics much of the pathology of ALS including a dysfunctional hypothalamic-pituitary-adrenal axis. We discuss recent studies that demonstrated that the pathological cascade characteristic for motoneuron degeneration of ALS is mimicked in the genetically selected Wobbler mouse and can be attenuated by treatment with the selective glucocorticoid receptor antagonist (GRA) CORT113176. In long-term treatment (3 weeks) GRA attenuated progression of the behavioral, inflammatory, excitatory, and cell-death-signaling pathways while increasing the survival signal of serine-threonine kinase (pAkt). The action mechanism of the GRA may be either by interfering with GR deactivation or by restoring the balance between pro- and anti-inflammatory signaling pathways driven by the complementary mineralocorticoid receptor (MR)- and GR-mediated actions of corticosterone. Accordingly, GR antagonism may have clinical relevance for the treatment of neurodegenerative diseases.
Assuntos
Doenças Neurodegenerativas/tratamento farmacológico , Receptores de Glucocorticoides/metabolismo , Animais , Corticosterona/sangue , Corticosterona/química , Modelos Animais de Doenças , Humanos , Inflamação/sangue , Inflamação/complicações , Modelos Biológicos , Doenças Neurodegenerativas/sangue , Receptores de Glucocorticoides/antagonistas & inibidoresRESUMO
The ventral tegmental area dopamine (VTA-DA) mesolimbic circuit processes emotional, motivational, and social reward associations together with their more demanding cognitive aspects that involve the mesocortical circuitry. Coping with stress increases VTA-DA excitability, but when the stressor becomes chronic the VTA-DA circuit is less active, which may lead to degeneration and local microglial activation. This switch between activation and inhibition of VTA-DA neurons is modulated by e.g. corticotropin-releasing hormone (CRH), opioids, brain-derived neurotrophic factor (BDNF), and the adrenal glucocorticoids. These actions are coordinated with energy-demanding stress-coping styles to promote behavioral adaptation. The VTA circuits show sexual dimorphism that is programmed by sex hormones during perinatal life in a manner that can be affected by glucocorticoid exposure. We conclude that insight in the role of stress in VTA-DA plasticity and connectivity, during reward processing and stress-coping, will be helpful to better understand the mechanism of resilience to breakdown of adaptation.
Assuntos
Adaptação Psicológica , Neurônios Dopaminérgicos , Rede Nervosa , Plasticidade Neuronal , Córtex Pré-Frontal , Caracteres Sexuais , Estresse Psicológico , Área Tegmentar Ventral , Adaptação Psicológica/fisiologia , Animais , Neurônios Dopaminérgicos/metabolismo , Humanos , Rede Nervosa/metabolismo , Rede Nervosa/fisiopatologia , Plasticidade Neuronal/fisiologia , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiopatologia , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia , Área Tegmentar Ventral/metabolismo , Área Tegmentar Ventral/fisiopatologiaRESUMO
The Wobbler mouse spinal cord shows vacuolated motoneurons, glial reaction, inflammation and abnormal glutamatergic parameters. Wobblers also show deficits of motor performance. These conditions resemble amyotrophic lateral sclerosis (ALS). Wobbler mice also show high levels of corticosterone in blood, adrenals and brain plus adrenal hypertrophy, suggesting that chronically elevated glucocorticoids prime spinal cord neuroinflammation. Therefore, we analyzed if treatment of Wobbler mice with the glucocorticoid receptor (GR) antagonist CORT113176 mitigated the mentioned abnormalities. 30â¯mg/kg CORT113176 given daily for 3â¯weeks reduced motoneuron vacuolation, decreased astro and microgliosis, lowered the inflammatory mediators high mobility group box 1 protein (HMGB1), toll-like receptor 4, myeloid differentiation primary response 88 (MyD88), p50 subunit of nuclear factor kappa B (NFκB), tumor necrosis factor (TNF) receptor, and interleukin 18 (IL18) compared to untreated Wobblers. CORT113176 increased the survival signal pAKT (serine-threonine kinase) and decreased the death signal phosphorylated Junk-N-terminal kinase (pJNK), symptomatic of antiapoptosis. There was a moderate positive effect on glutamine synthase and astrocyte glutamate transporters, suggesting decreased glutamate excitotoxicity. In this pre-clinical study, Wobblers receiving CORT113176 showed enhanced resistance to fatigue in the rota rod test and lower forelimb atrophy at weeks 2-3. Therefore, long-term treatment with CORT113176 attenuated degeneration and inflammation, increased motor performance and decreased paw deformity. Antagonism of the GR may be of potential therapeutic value for neurodegenerative diseases.
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Isoquinolinas/administração & dosagem , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/patologia , Pirazóis/administração & dosagem , Receptores de Glucocorticoides/antagonistas & inibidores , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Encefalite/patologia , Feminino , Ácido Glutâmico/toxicidade , Masculino , Camundongos , Microglia/efeitos dos fármacos , Microglia/patologiaRESUMO
The forced swim test (FST) for rodents does not model despair or helplessness. It also is not a read-out for depression, anxiety, psychomotor retardation or autism, because these are anthropomorphic interpretations of the rodent's acquired immobility. Rather, the transition from swimming to immobility allows to examine the mechanistic underpinning of coping with inescapable stressors. However, in a recent detailed analysis of the FST application over the past 40 years, we noted a dramatic surge in the use of this test to phenotype animals as 'depressed'. As a follow up to that report, we now present an analysis of the use of the FST over the past three years. This literature analysis shows that the popularity of the FST is still increasing and that the majority of researchers qualifies the rodent's floating response as depressive-like behavior. However, over the past few years we also note a trend to interpret immobility rather as the expression of a coping strategy. In view of this result, we have sent a poll to the relevant authors to learn how consistent they are in naming FST behavior. Remarkably, we find a dramatic inverse correlation between their first qualification of acquired immobility as depressive-like behavior towards their current interpretation as coping strategy. In this contribution we have embedded our literature analysis and poll results in an update on the management of coping with inescapable stressors by processing in prefrontal cortical circuitry and glucocorticoid feedback.
Assuntos
Modelos Animais de Doenças , Estresse Fisiológico/fisiologia , Estresse Psicológico/metabolismo , Adaptação Psicológica , Animais , Ansiedade , Transtornos de Ansiedade , Comportamento Animal/fisiologia , Depressão , Transtorno Depressivo , Aprendizagem , Córtex Pré-Frontal , NataçãoRESUMO
Psychotic depression is characterized by elevated circulating cortisol, and high daily doses of the glucocorticoid/progesterone antagonist mifepristone for 1 week are required for significant improvement. Using a rodent model, we find that such high doses of mifepristone are needed because the antagonist is rapidly degraded and poorly penetrates the blood-brain barrier, but seems to facilitate the entry of cortisol. We also report that in male C57BL/6J mice, after a 7-day treatment with a high dose of mifepristone, basal blood corticosterone levels were similar to that of vehicle controls. This is surprising because after the first mifepristone challenge, corticosterone remained elevated for about 16 h, and then decreased towards vehicle control levels at 24 h. At that time, stress-induced corticosterone levels of the 1xMIF were sevenfold higher than the 7xMIF group, the latter response being twofold lower than controls. The 1xMIF mice showed behavioral hyperactivity during exploration of the circular hole board, while the 7xMIF mice rather engaged in serial search patterns. To explain this rapid reset of corticosterone secretion upon recurrent mifepristone administration, we suggest the following: (i) A rebound glucocorticoid feedback after cessation of mifepristone treatment. (ii) Glucocorticoid agonism in transrepression and recruitment of cell-specific coregulator cocktails. (iii) A more prominent role of brain MR function in control of stress circuit activity. An overview table of neuroendocrine MIF effects is provided. The data are of interest for understanding the mechanistic underpinning of stress system reset as treatment strategy for stress-related diseases.
Assuntos
Mifepristona/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Ritmo Circadiano/efeitos dos fármacos , Corticosterona/sangue , Corticosterona/metabolismo , Hormônio Liberador da Corticotropina/genética , Hormônio Liberador da Corticotropina/metabolismo , Humanos , Hidrocortisona/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Mifepristona/administração & dosagem , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Glucocorticoides/antagonistas & inibidores , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/genética , Receptores de Mineralocorticoides/metabolismoRESUMO
Wobbler mice are experimental models for amyotrophic lateral sclerosis. As such they show motoneuron degeneration, motor deficits, and astrogliosis and microgliosis of the spinal cord. Additionally, Wobbler mice show increased plasma, spinal cord and brain corticosterone levels and focal adrenocortical hyperplasia, suggesting a pathogenic role for glucocorticoids in this disorder. Considering this endocrine background, we examined whether the glucocorticoid receptor (GR) modulator CORT 113176 prevents spinal cord neuropathology of Wobblers. CORT 113176 shows high affinity for the GR, with low or null affinity for other steroid receptors. We employed five-month-old genotyped Wobbler mice that received s.c. vehicle or 30â¯mg/kg/day for 4â¯days of CORT 113176 dissolved in sesame oil. The mice were used on the 4th day, 2â¯h after the last dose of CORT 113176. Vehicle-treated Wobbler mice presented vacuolated motoneurons, increased glial fibrillary acidic protein (GFAP)+ astrocytes and decreased glutamine synthase (GS)+ cells. There was strong neuroinflammation, shown by increased staining for IBA1+ microglia and CD11b mRNA, enhanced expression of tumor necrosis factor-α, its cognate receptor TNFR1, toll-like receptor 4, the inducible nitric oxide synthase, NFkB and the high-mobility group box 1 protein (HMGB1). Treatment of Wobbler mice with CORT 113176 reversed the abnormalities of motoneurons and down-regulated proinflammatory mediators and glial reactivity. Expression of glutamate transporters GLT1 and GLAST mRNAs and GLT1 protein was significantly enhanced over untreated Wobblers. In summary, antagonism of GR with CORT 113176 prevented neuropathology and showed anti-inflammatory and anti-glutamatergic effects in the spinal cord of Wobbler mice.
Assuntos
Esclerose Lateral Amiotrófica/patologia , Inflamação/tratamento farmacológico , Isoquinolinas/uso terapêutico , Degeneração Neural/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Pirazóis/uso terapêutico , Receptores de Glucocorticoides/antagonistas & inibidores , Medula Espinal/efeitos dos fármacos , Esclerose Lateral Amiotrófica/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Astrócitos/patologia , Modelos Animais de Doenças , Proteína Glial Fibrilar Ácida/metabolismo , Inflamação/metabolismo , Inflamação/patologia , Isoquinolinas/farmacologia , Camundongos , Camundongos Mutantes Neurológicos , Degeneração Neural/metabolismo , Degeneração Neural/patologia , Fármacos Neuroprotetores/farmacologia , Pirazóis/farmacologia , Medula Espinal/metabolismo , Medula Espinal/patologia , Resultado do TratamentoRESUMO
OBJECTIVE: Menstrual cycle phase and oral contraceptives (OC) use influence mood and cognition and these effects may be moderated by the mineralocorticoid receptor (MR) genotype. The effect of menstrual cycle phase on mood may be increased if participants know that this is the focus of study. We assessed aspects associated with reproductive depression such as mood, interpersonal sensitivity, affect lability and depressive cognitions in MR-genotyped OC-users and naturally cycling (NC) women in a carefully masked design. METHODS: A homogenous sample of healthy, PMS-free, pre-menopausal MR-genotyped women (n=92) completed online questionnaires eight times during two consecutive cycles. RESULTS: The masking of the research question was successful. OC-users did not differ significantly from NC women in positive and negative affect at the time of assessment, personality characteristics (e.g. neuroticism) or mental and physical health. Both groups reported more shifts in anger in the first cycle week (p<0.001; ηp2=0.08). Compared to NC women, OC-users reported fewer mood-shifts between depression and elation in the mid-luteal phase of the menstrual cycle (p=0.002; ηp2=0.10) and had fewer ruminating thoughts at all phases (p=0.003; ηp2=0.11). Effects of MR-genotype were not significant after correction for multiple comparisons. CONCLUSION: OC users scored more favorably on measures associated with reproductive depression. OC users also showed a decreased affect variability possibly indicating an emotional blunting effect, which is in line with previous reports on affect-stabilizing effects of OC. Limitations were loss of cases due to irregularities in the menstrual cycle length and possible confounding by the 'survivor effect', since almost all OC-users took OC for more than a year.
Assuntos
Afeto/efeitos dos fármacos , Anticoncepcionais Orais/uso terapêutico , Ciclo Menstrual/psicologia , Adulto , Anticoncepcionais Orais/farmacologia , Feminino , Voluntários Saudáveis , Humanos , Estudos Longitudinais , Estudos Prospectivos , Adulto JovemRESUMO
In 1968, Bruce McEwen discovered that 3H-corticosterone administered to adrenalectomised rats is retained in neurons of hippocampus rather than those of hypothalamus. This discovery signalled the expansion of endocrinology into the science of higher brain regions. With this in mind, our contribution highlights the saga of the brain mineralocorticoid receptor (MR) in three episodes. First, the precloning era dominated by the conundrum of two types of corticosterone-binding receptors in the brain, which led to the identification of the high-affinity corticosterone receptor as the 'promiscuous' MR cloned in 1987 by Jeff Arriza and Ron Evans in addition to the classical glucocorticoid receptor (GR). Then, the post-cloning period aimed to disentangle the function of the brain MR from that of the closely related GR on different levels of biological complexity. Finally, the synthesis section that highlights the two faces of brain MR: Salt and Stress. 'Salt' refers to the regulation of salt appetite, and reciprocal arousal, motivation and reward, by a network of aldosterone-selective MR-expressing neurons projecting from nucleus tractus solitarii (NTS) and circumventricular organs. 'Stress' is about the limbic-forebrain nuclear and membrane MRs, which act as a switch in the selection of the best response to cope with a stressor. For this purpose, activation of the limbic MR promotes selective attention, memory retrieval and the appraisal process, while driving emotional expressions of fear and aggression. Subsequently, rising glucocorticoid concentrations activate GRs in limbic-forebrain circuitry underlying executive functions and memory storage, which contribute in balance with MR-mediated actions to homeostasis, excitability and behavioural adaptation.
Assuntos
Encéfalo/metabolismo , Receptores de Mineralocorticoides/metabolismo , Animais , Clonagem Molecular , Regulação da Expressão Gênica/fisiologia , Rede Nervosa/fisiologia , Neuroendocrinologia , Receptores de Mineralocorticoides/genéticaRESUMO
In the limbic brain, mineralocorticoid receptors (MRs) and glucocorticoid receptors (GRs) both function as receptors for the naturally occurring glucocorticoids (corticosterone/cortisol) but mediate distinct effects on cellular physiology via transcriptional mechanisms. The transcriptional basis for specificity of these MR- vs GR-mediated effects is unknown. To address this conundrum, we have identified the extent of MR/GR DNA-binding selectivity in the rat hippocampus using chromatin immunoprecipitation followed by sequencing. We found 918 and 1450 nonoverlapping binding sites for MR and GR, respectively. Furthermore, 475 loci were co-occupied by MR and GR. De novo motif analysis resulted in a similar binding motif for both receptors at 100% of the target loci, which matched the known glucocorticoid response element (GRE). In addition, the Atoh/NeuroD consensus sequence was found in co-occurrence with all MR-specific binding sites but was absent for GR-specific or MR-GR overlapping sites. Basic helix-loop-helix family members Neurod1, Neurod2, and Neurod6 showed hippocampal expression and were hypothesized to bind the Atoh motif. Neurod2 was detected at rat hippocampal MR binding sites but not at GR-exclusive sites. All three NeuroD transcription factors acted as DNA-binding-dependent coactivators for both MR and GR in reporter assays in heterologous HEK293 cells, likely via indirect interactions with the receptors. In conclusion, a NeuroD family member binding to an additional motif near the GRE seems to drive specificity for MR over GR binding at hippocampal binding sites.
Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Encéfalo/metabolismo , Neuropeptídeos/fisiologia , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , Elementos de Resposta/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sítios de Ligação , DNA/metabolismo , Feminino , Células HEK293 , Humanos , Masculino , Neuropeptídeos/metabolismo , Ligação Proteica , Ratos , Ratos Sprague-DawleyRESUMO
Some serious medical conditions require life-saving treatment with high doses of synthetic glucocorticoids such as dexamethasone. A substantial number of patients subjected to this treatment develops psychosis, mood disturbances, or sleep problems. A recent clinical trial demonstrated that dexamethasone therapy for young patients with acute lymphoblastic leukemia caused severe adverse psychological effects and sleep disturbances in about 30% of these patients. These side effects were ameliorated by coadministration of a low dose of the naturally occurring glucocorticoid hormone cortisol. This paradoxical finding was predicted by the idea that the synthetic glucocorticoid targets the glucocorticoid receptor, causing suppression of cortisol secretion and, thus, depletion of the brain mineralocorticoid receptor (MR) of its endogenous ligand. The refill of the unoccupied brain MR with physiological amounts of cortisol ameliorates the dexamethasone-induced psychological side effects. In the present report, we discuss the mechanistic underpinning of the MR refill concept in glucocorticoid therapy.
Assuntos
Dexametasona/efeitos adversos , Glucocorticoides/efeitos adversos , Hidrocortisona/administração & dosagem , Transtornos Mentais/prevenção & controle , Receptores de Mineralocorticoides/agonistas , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Retroalimentação Fisiológica , Glucocorticoides/administração & dosagem , Humanos , Transtornos Mentais/induzido quimicamente , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismoRESUMO
BACKGROUND: Carriers of MR-haplotype 1 and 3 (GA/CG; rs5522 and rs2070951) are more sensitive to the influence of oral contraceptives (OC) and menstrual cycle phase on emotional information processing than MR-haplotype 2 (CA) carriers. We investigated whether this effect is associated with estradiol (E2) and/or progesterone (P4) levels. METHOD: Healthy MR-genotyped premenopausal women were tested twice in a counterbalanced design. Naturally cycling (NC) women were tested in the early-follicular and mid-luteal phase and OC-users during OC-intake and in the pill-free week. At both sessions E2 and P4 were assessed in saliva. Tests included implicit and explicit positive and negative affect, attentional blink accuracy, emotional memory, emotion recognition, and risky decision-making (gambling). RESULTS: MR-haplotype 2 homozygotes had higher implicit happiness scores than MR-haplotype 2 heterozygotes (p=0.031) and MR-haplotype 1/3 carriers (p<0.001). MR-haplotype 2 homozygotes also had longer reaction times to happy faces in an emotion recognition test than MR-haplotype 1/3 (p=0.001). Practice effects were observed for most measures. The pattern of correlations between information processing and P4 or E2 differed between sessions, as well as the moderating effects of the MR genotype. In the first session the MR-genotype moderated the influence of P4 on implicit anxiety (sr=-0.30; p=0.005): higher P4 was associated with reduction in implicit anxiety, but only in MR-haplotype 2 homozygotes (sr=-0.61; p=0.012). In the second session the MR-genotype moderated the influence of E2 on the recognition of facial expressions of happiness (sr=-0.21; p=0.035): only in MR-haplotype 1/3 higher E2 was correlated with happiness recognition (sr=0.29; p=0.005). In the second session higher E2 and P4 were negatively correlated with accuracy in lag2 trials of the attentional blink task (p<0.001). Thus NC women, compared to OC-users, performed worse on lag 2 trials (p=0.041). CONCLUSION: The higher implicit happiness scores of MR-haplotype 2 homozygotes are in line with previous reports. Performance in the attentional blink task may be influenced by OC-use. The MR-genotype moderates the influence of E2 and P4 on emotional information processing. This moderating effect may depend on the novelty of the situation.
Assuntos
Intermitência na Atenção Visual/fisiologia , Emoções/fisiologia , Estradiol/metabolismo , Expressão Facial , Reconhecimento Facial/fisiologia , Ciclo Menstrual/metabolismo , Progesterona/metabolismo , Receptores de Mineralocorticoides/genética , Adolescente , Adulto , Intermitência na Atenção Visual/genética , Anticoncepcionais Orais , Feminino , Haplótipos , Humanos , Saliva/química , Adulto JovemRESUMO
Adrenal glucocorticoids are major modulators of multiple functions, including energy metabolism, stress responses, immunity, and cognition. The endogenous secretion of glucocorticoids is normally characterized by a prominent and robust circadian (around 24 hours) oscillation, with a daily peak around the time of the habitual sleep-wake transition and minimal levels in the evening and early part of the night. It has long been recognized that this 24-hour rhythm partly reflects the activity of a master circadian pacemaker located in the suprachiasmatic nucleus of the hypothalamus. In the past decade, secondary circadian clocks based on the same molecular machinery as the central master pacemaker were found in other brain areas as well as in most peripheral tissues, including the adrenal glands. Evidence is rapidly accumulating to indicate that misalignment between central and peripheral clocks has a host of adverse effects. The robust rhythm in circulating glucocorticoid levels has been recognized as a major internal synchronizer of the circadian system. The present review examines the scientific foundation of these novel advances and their implications for health and disease prevention and treatment.
Assuntos
Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Glucocorticoides/fisiologia , Animais , Glucocorticoides/metabolismo , HumanosRESUMO
RATIONALE: The processing of emotional information is affected by menstrual cycle phase and by the use of oral contraceptives (OCs). The stress hormone cortisol is known to affect emotional information processing via the limbic mineralocorticoid receptor (MR). OBJECTIVES: We investigated in an exploratory study whether the MR-genotype moderates the effect of both OC-use and menstrual cycle phase on emotional cognition. METHODS: Healthy premenopausal volunteers (n=93) of West-European descent completed a battery of emotional cognition tests. Forty-nine participants were OC users and 44 naturally cycling, 21 of whom were tested in the early follicular (EF) and 23 in the mid-luteal (ML) phase of the menstrual cycle. RESULTS: In MR-haplotype 1/3 carriers, ML women gambled more than EF women when their risk to lose was relatively small. In MR-haplotype 2, ML women gambled more than EF women, regardless of their odds of winning. OC-users with MR-haplotype 1/3 recognised fewer facial expressions than ML women with MR-haplotype 1/3. CONCLUSION: MR-haplotype 1/3 carriers may be more sensitive to the influence of their female hormonal status. MR-haplotype 2 carriers showed more risky decision-making. As this may reflect optimistic expectations, this finding may support previous observations in female carriers of MR-haplotype 2 in a naturalistic cohort study.
Assuntos
Anticoncepcionais Orais/administração & dosagem , Emoções/efeitos dos fármacos , Fase Folicular/efeitos dos fármacos , Haplótipos/genética , Fase Luteal/efeitos dos fármacos , Receptores de Mineralocorticoides/metabolismo , Adulto , Estudos Transversais , Tomada de Decisões/efeitos dos fármacos , Expressão Facial , Feminino , Fase Folicular/metabolismo , Humanos , Fase Luteal/metabolismo , Adulto JovemRESUMO
The forced swim test is based on the progressive immobility a rodent displays when immersed in a beaker filled with water from where no escape is possible. While the test was originally designed to identify the antidepressant potential of drugs, over the past decade a rapidly growing number of publications (more than 2000) portray this immobility response anthropomorphically as a measure for depression and despair. This is incorrect. The response to the forced swim stressor should be considered for what it shows: a switch from active to passive behavior in the face of an acute stressor, aligned to cognitive functions underlying behavioral adaptation and survival.