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1.
J Psychopharmacol ; 37(6): 577-589, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37165642

RESUMO

BACKGROUND: Up to 40% of patients suffering from anxiety disorders do not benefit from currently available pharmacological treatments. Overactivity of the orexin-1 receptor (OX1R) has been implicated in anxiety- and panic-related states. AIM & METHODS: We investigated the pharmacokinetics and characterized the pharmacodynamic (PD) profile of the OX1R antagonist JNJ-61393215 using a battery of central nervous system assessments investigating relevant functional domains such as alertness, attention, (visuo)motor coordination, balance, subjective effects and resting-state electroencephalography in a single ascending dose placebo-controlled study in doses from 1 to 90 mg inclusive, assessing PD up to 10 h after dosing, safety and pharmacokinetic in 48 healthy male subjects. RESULTS: Average time to maximal plasma concentration (Tmax) ranged between 1.0 and 2.25 h; average half-life ranged from 13.6 to 24.6 h and average maximum plasma concentration ranged from 1.4 to 136.8 ng/mL in the 1 and 90 mg groups, respectively. JNJ-61393215 did not demonstrate any statistically significant or clinically meaningful effects on any PD endpoint at any dose investigated at Tmax nor over the total period up to 10 h post-dose and was well tolerated. The reported somnolence rate was 16.7% (which was attributable to the cohorts receiving 6 mg and higher doses) compared to 12.5% in placebo. CONCLUSION: This observation is in line with our knowledge about the OX1R in preclinical studies, where only inconsistent and non-dose-dependent changes in electroencephalography or other behavioural measures were observed under non-challenged conditions, potentially exemplifying the need for a challenged subject.


Assuntos
Antagonistas dos Receptores de Orexina , Humanos , Masculino , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , Meia-Vida , Voluntários Saudáveis , Antagonistas dos Receptores de Orexina/efeitos adversos , Antagonistas dos Receptores de Orexina/farmacocinética , Orexinas
2.
Transl Psychiatry ; 7(5): e1115, 2017 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-28463241

RESUMO

A subgroup of individuals with mood and psychotic disorders shows evidence of inflammation that leads to activation of the kynurenine pathway and the increased production of neuroactive kynurenine metabolites. Depression is hypothesized to be causally associated with an imbalance in the kynurenine pathway, with an increased metabolism down the 3-hydroxykynurenine (3HK) branch of the pathway leading to increased levels of the neurotoxic metabolite, quinolinic acid (QA), which is a putative N-methyl-d-aspartate (NMDA) receptor agonist. In contrast, schizophrenia and psychosis are hypothesized to arise from increased metabolism of the NMDA receptor antagonist, kynurenic acid (KynA), leading to hypofunction of GABAergic interneurons, the disinhibition of pyramidal neurons and striatal hyperdopaminergia. Here we present results that challenge the model of excess KynA production in affective psychosis. After rigorous control of potential confounders and multiple testing we find significant reductions in serum KynA and/or KynA/QA in acutely ill inpatients with major depressive disorder (N=35), bipolar disorder (N=53) and schizoaffective disorder (N=40) versus healthy controls (N=92). No significant difference was found between acutely ill inpatients with schizophrenia (n=21) and healthy controls. Further, a post hoc comparison of patients divided into the categories of non-psychotic affective disorder, affective psychosis and psychotic disorder (non-affective) showed that the greatest decrease in KynA was in the affective psychosis group relative to the other diagnostic groups. Our results are consistent with reports of elevations in proinflammatory cytokines in psychosis, and preclinical work showing that inflammation upregulates the enzyme, kynurenine mono-oxygenase (KMO), which converts kynurenine into 3-hydroxykynurenine and quinolinic acid.


Assuntos
Transtornos Psicóticos Afetivos/metabolismo , Ácido Cinurênico/sangue , Quinurenina 3-Mono-Oxigenase/metabolismo , Adulto , Transtornos Psicóticos Afetivos/sangue , Transtornos Psicóticos Afetivos/fisiopatologia , Transtorno Bipolar/metabolismo , Corpo Estriado/metabolismo , Citocinas/metabolismo , Depressão/metabolismo , Transtorno Depressivo Maior/metabolismo , Feminino , Neurônios GABAérgicos/metabolismo , Humanos , Inflamação/enzimologia , Ácido Cinurênico/metabolismo , Cinurenina/análogos & derivados , Cinurenina/metabolismo , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/metabolismo , Ácido Quinolínico/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Esquizofrenia/metabolismo
3.
Psychol Med ; 47(15): 2640-2652, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28446254

RESUMO

BACKGROUND: Females are more likely than males to develop major depressive disorder (MDD). The current study used fMRI to compare the neural correlates of autobiographical memory (AM) recall between males and females diagnosed with MDD. AM overgenerality is a persistent cognitive deficit in MDD, the magnitude of which is correlated with depressive severity only in females. Delineating the neurobiological correlates of this deficit may elucidate the nature of sex-differences in the diathesis for developing MDD. METHODS: Participants included unmedicated males and females diagnosed with MDD (n = 20/group), and an age and sex matched healthy control group. AM recall in response to positive, negative, and neutral cue words was compared with a semantic memory task. RESULTS: The behavioral properties of AMs did not differ between MDD males and females. In contrast, main effects of sex on cerebral hemodynamic activity were observed in left dorsolateral prefrontal cortex and parahippocampal gyrus during recall of positive specific memories, and middle prefrontal cortex (mPFC), and precuneus during recall of negative specific memories. Moreover, main effects of diagnosis on regional hemodynamic activity were observed in left ventrolateral prefrontal cortex and mPFC during positive specific memory recall, and dorsal anterior cingulate cortex during negative specific memory recall. Sex × diagnosis interactions were evident in the dorsomedial prefrontal cortex, caudate, and precuneus during positive memory recall, and in the posterior cingulate cortex, insula, precuneus and thalamus during negative specific memory recall. CONCLUSIONS: The differential hemodynamic changes conceivably may reflect sex-specific cognitive strategies during recall of AMs irrespective of the phenomenological properties of those memories.


Assuntos
Mapeamento Encefálico/métodos , Núcleo Caudado/fisiopatologia , Córtex Cerebral/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Memória Episódica , Rememoração Mental/fisiologia , Acoplamento Neurovascular/fisiologia , Caracteres Sexuais , Tálamo/fisiopatologia , Adulto , Núcleo Caudado/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Transtorno Depressivo Maior/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tálamo/diagnóstico por imagem , Adulto Jovem
4.
Transl Psychiatry ; 7(2): e1025, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28170001

RESUMO

Post-traumatic stress disorder (PTSD) is psychiatric disease, which can occur following exposure to traumatic events. PTSD may be acute or chronic, and can have a waxing and waning course of symptoms. It has been hypothesized that proinflammatory cytokines and chemokines in the cerebrospinal fluid (CSF) or plasma might be mediators of the psychophysiological mechanisms relating a history of trauma exposure to changes in behavior and mental health disorders, and medical morbidity. Here we test the cytokine/chemokine hypothesis for PTSD by examining levels of 17 classical cytokines and chemokines in CSF, sampled at 0900 hours, and in plasma sampled hourly for 24 h. The PTSD and healthy control patients are from the NIMH Chronic PTSD and healthy control cohort, initially described by Bonne et al. (2011), in which the PTSD patients have relatively low comorbidity for major depressive disorder (MDD), drug or alcohol use. We find that in plasma, but not CSF, the bivariate MCP4 (CCL13)/ MCP1(CCL2) ratio is ca. twofold elevated in PTSD patients compared with healthy controls. The MCP-4/MCP-1 ratio is invariant over circadian time, and is independent of gender, body mass index or the age at which the trauma was suffered. By contrast, MIP-1ß is a candidate biomarker for PTSD only in females, whereas TARC is a candidate biomarker for PTSD only in males. It remains to be discovered whether these disease-specific differences in circadian expression for these specific immune signaling molecules are biomarkers, surrogates, or drivers for PTSD, or whether any of these analytes could contribute to therapy.


Assuntos
Quimiocina CCL2/metabolismo , Proteínas Quimioatraentes de Monócitos/metabolismo , Transtornos de Estresse Pós-Traumáticos/metabolismo , Adulto , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Quimiocina CCL17/metabolismo , Quimiocina CCL4/metabolismo , Doença Crônica , Ritmo Circadiano , Citocinas/metabolismo , Feminino , Humanos , Masculino , Fatores Sexuais
5.
Transl Psychiatry ; 6(9): e889, 2016 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-27622933

RESUMO

Genetic predisposition may contribute to the differences in drug-specific, class-specific or antidepressant-wide treatment resistance. Clinical studies with the genetic data are often limited in sample sizes. Drug response obtained from self-reports may offer an alternative approach to conduct a study with much larger sample size. Using the phenotype data collected from 23andMe 'Antidepressant Efficacy and Side Effects' survey and genotype data from 23andMe's research participants, we conducted genome-wide association study (GWAS) on subjects of European ancestry using four groups of phenotypes (a) non-treatment-resistant depression (n=7795) vs treatment-resistant depression (TRD, n=1311), (b) selective serotonin reuptake inhibitors (SSRI) responders (n=6348) vs non-responders (n=3340), (c) citalopram/escitalopram responders (n=2963) vs non-responders (n=2005), and (d) norepinephrine-dopamine reuptake inhibitor (NDRI, bupropion) responders (n=2675) vs non-responders (n=1861). Each of these subgroups was also compared with controls (n ~ 190 000). The most significant association was from bupropion responders vs non-responders analysis. Variant rs1908557 (P=2.6 × 10(-8), OR=1.35) passed the conventional genome-wide significance threshold (P=5 × 10(-8)) and was located within the intron of human spliced expressed sequence tags in chromosome 4. Gene sets associated with long-term depression, circadian rhythm and vascular endothelial growth factor (VEGF) pathway were enriched in the bupropion analysis. No single-nucleotide polymorphism passed genome-wide significance threshold in other analyses. The heritability estimates for each response group compared with controls were between 0.15 and 0.25, consistent with the known heritability for major depressive disorder.


Assuntos
Antidepressivos/uso terapêutico , Bupropiona/uso terapêutico , Citalopram/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Resistência a Medicamentos/genética , Adulto , Cromossomos Humanos Par 4/genética , Ritmo Circadiano/genética , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/genética , Transtorno Depressivo Maior/genética , Transtorno Depressivo Resistente a Tratamento/genética , Inibidores da Captação de Dopamina/uso terapêutico , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Plasticidade Neuronal/genética , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Transdução de Sinais , Inquéritos e Questionários , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular
6.
Transl Psychiatry ; 6(9): e894, 2016 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-27648916

RESUMO

Ketamine, at sub-anesthetic doses, is reported to rapidly decrease depression symptoms in patients with treatment-resistant major depressive disorder (MDD). Many patients do not respond to currently available antidepressants, (for example, serotonin reuptake inhibitors), making ketamine and its enantiomer, esketamine, potentially attractive options for treatment-resistant MDD. Although mechanisms by which ketamine/esketamine may produce antidepressant effects have been hypothesized on the basis of preclinical data, the neurobiological correlates of the rapid therapeutic response observed in patients receiving treatment have not been established. Here we use a pharmacometabolomics approach to map global metabolic effects of these compounds in treatment-refractory MDD patients upon 2 h from infusion with ketamine (n=33) or its S-enantiomer, esketamine (n=20). The effects of esketamine on metabolism were retested in the same subjects following a second exposure administered 4 days later. Two complementary metabolomics platforms were used to provide broad biochemical coverage. In addition, we investigated whether changes in particular metabolites correlated with treatment outcome. Both drugs altered metabolites related to tryptophan metabolism (for example, indole-3-acetate and methionine) and/or the urea cycle (for example, citrulline, arginine and ornithine) at 2 h post infusion (q<0.25). In addition, we observed changes in glutamate and circulating phospholipids that were significantly associated with decreases in depression severity. These data provide new insights into the mechanism underlying the rapid antidepressant effects of ketamine and esketamine, and constitute some of the first detailed metabolomics mapping for these promising therapies.


Assuntos
Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Ketamina/uso terapêutico , Metabolômica , Adulto , Arginina/metabolismo , Citrulina/metabolismo , Transtorno Depressivo Maior/metabolismo , Transtorno Depressivo Resistente a Tratamento/metabolismo , Feminino , Ácido Glutâmico/metabolismo , Humanos , Ácidos Indolacéticos/metabolismo , Infusões Intravenosas , Masculino , Metionina/metabolismo , Pessoa de Meia-Idade , Ornitina/metabolismo , Fenótipo , Fosfolipídeos/metabolismo , Triptofano/metabolismo , Ureia/metabolismo
7.
Transl Psychiatry ; 5: e591, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-26125154

RESUMO

Individuals with high-trait anxiety frequently report decreased perceived control. However, it is unclear how these processes are instantiated at a neural level. Prior research suggests that individuals prone to anxiety may have exaggerated activity in the anterior insula and altered activity in the cingulate cortex during anticipation of aversive events. Thus, we hypothesized that anxiety proneness influences anterior insula activation during anticipation of unpredictable threat through decreased perceived control. Forty physically healthy adults underwent neuroimaging while they explored computer-simulated contexts associated either with or without the threat of an unpredictable shock. Skin conductance, anxiety ratings and blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging were used to assess responses to threat versus no threat. Perceived control was measured using the Anxiety Control Questionnaire-Revised. Mediation analysis examined how anxiety proneness influenced BOLD activity. Anticipation of unpredictable threat resulted in increased skin conductance responses, anxiety ratings and enhanced activation in bilateral insula, anterior midcingulate cortex (aMCC) and bed nucleus of the stria terminalis. Individuals with greater anxiety proneness and less perceived control showed greater activity in dorsal anterior insula (dAI). Perceived control mediated the relationship between anxiety proneness and dAI activity. Increased dAI activity was associated with increased activity in aMCC, which correlated with increased exploratory behavior. Results provide evidence that exaggerated insula activation during the threat of unpredictable shock is directly related to low perceived control in anxiety-prone individuals. Perceived control thus may constitute an important treatment target to modulate insula activity during anxious anticipation in anxiety-disordered individuals.


Assuntos
Ansiedade/fisiopatologia , Córtex Cerebral/fisiopatologia , Adulto , Ansiedade/psicologia , Estimulação Elétrica , Feminino , Neuroimagem Funcional , Resposta Galvânica da Pele , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Percepção , Personalidade , Adulto Jovem
8.
Transl Psychiatry ; 5: e532, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25781231

RESUMO

Despite immense efforts into development of new antidepressant drugs, the increases of serotoninergic and catecholaminergic neurotransmission have remained the two major pharmacodynamic principles of current drug treatments for depression. Consequently, psychopathological or biological markers that predict response to drugs that selectively increase serotonin and/or catecholamine neurotransmission hold the potential to optimize the prescriber's selection among currently available treatment options. The aim of this study was to elucidate the differential symptomatology and neurophysiology in response to reductions in serotonergic versus catecholaminergic neurotransmission in subjects at high risk of depression recurrence. Using identical neuroimaging procedures with [(18)F] fluorodeoxyglucose positron emission tomography after tryptophan depletion (TD) and catecholamine depletion (CD), subjects with remitted depression were compared with healthy controls in a double-blind, randomized, crossover design. Although TD induced significantly more depressed mood, sadness and hopelessness than CD, CD induced more inactivity, concentration difficulties, lassitude and somatic anxiety than TD. CD specifically increased glucose metabolism in the bilateral ventral striatum and decreased glucose metabolism in the bilateral orbitofrontal cortex, whereas TD specifically increased metabolism in the right prefrontal cortex and the posterior cingulate cortex. Although we found direct associations between changes in brain metabolism and induced depressive symptoms following CD, the relationship between neural activity and symptoms was less clear after TD. In conclusion, this study showed that serotonin and catecholamines have common and differential roles in the pathophysiology of depression.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Catecolaminas/deficiência , Transtorno Depressivo/metabolismo , Transtorno Depressivo/psicologia , Serotonina/deficiência , Adolescente , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Fluordesoxiglucose F18 , Glucose/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Índice de Gravidade de Doença , Adulto Jovem
9.
Psychol Med ; 44(14): 2951-63, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25065602

RESUMO

BACKGROUND: Individuals with major depressive disorder (MDD) tested in either the depressed (dMDD) or remitted phase (rMDD) recall fewer specific and more categorical autobiographical memories (AMs) compared to healthy controls (HCs). The current study aimed to replicate findings of AM overgenerality in dMDD or rMDD, and to elucidate differences in neurophysiological correlates of AM recall between these MDD samples and HCs. METHOD: Unmedicated participants who met criteria for the dMDD, rMDD or HC groups (n = 16/group) underwent functional magnetic resonance imaging (fMRI) while recalling AMs in response to emotionally valenced cue words. Control tasks involved generating examples from an assigned semantic category and counting the number of risers in a letter string. RESULTS: The results showed fewer specific and more categorical AMs in both MDD samples versus HCs; dMDDs and rMDDs performed similarly on these measures. The neuroimaging results showed differences between groups in the dorsomedial prefrontal cortex (DMPFC), lateral orbitofrontal cortex (OFC), anterior insula, inferior temporal gyrus and parahippocampus/hippocampus during specific AM recall versus example generation. During specific AM recall cued by positively valenced words, group differences were evident in the DMPFC, middle temporal gyrus, parahippocampus/hippocampus and occipital gyrus, whereas differences during specific AM recall cued by negatively valenced words were evident in the DMPFC, superior temporal gyrus and hippocampus. CONCLUSIONS: AM deficits exist in rMDDs, suggesting that these impairments constitute trait-like abnormalities in MDD. We also found distinct patterns of hemodynamic activity for each group as they recalled specific AMs, raising the possibility that each group used a partly unique strategy for self-referential focus during successful retrieval of specific memories.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Memória Episódica , Rememoração Mental/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
11.
Mol Psychiatry ; 18(5): 528-39, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23546169

RESUMO

In response to queries about whether brain imaging technology has reached the point where it is useful for making a clinical diagnosis and for helping to guide treatment selection, the American Psychiatric Association (APA) has recently written a position paper on the Clinical Application of Brain Imaging in Psychiatry. The following perspective piece is based on our contribution to this APA position paper, which specifically emphasized the application of neuroimaging in mood disorders. We present an introductory overview of the challenges faced by researchers in developing valid and reliable biomarkers for psychiatric disorders, followed by a synopsis of the extant neuroimaging findings in mood disorders, and an evidence-based review of the current research on brain imaging biomarkers in adult mood disorders. Although there are a number of promising results, by the standards proposed below, we argue that there are currently no brain imaging biomarkers that are clinically useful for establishing diagnosis or predicting treatment outcome in mood disorders.


Assuntos
Encéfalo/patologia , Transtornos do Humor/diagnóstico , Neuroimagem , Biomarcadores/metabolismo , Encéfalo/diagnóstico por imagem , Medicina Baseada em Evidências , Humanos , Neuroimagem/métodos , Neuroimagem/normas , Cintilografia , Reprodutibilidade dos Testes , Estados Unidos , United States Food and Drug Administration
12.
Transl Psychiatry ; 2: e154, 2012 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-22892719

RESUMO

Most pathway and gene-set enrichment methods prioritize genes by their main effect and do not account for variation due to interactions in the pathway. A portion of the presumed missing heritability in genome-wide association studies (GWAS) may be accounted for through gene-gene interactions and additive genetic variability. In this study, we prioritize genes for pathway enrichment in GWAS of bipolar disorder (BD) by aggregating gene-gene interaction information with main effect associations through a machine learning (evaporative cooling) feature selection and epistasis network centrality analysis. We validate this approach in a two-stage (discovery/replication) pathway analysis of GWAS of BD. The discovery cohort comes from the Wellcome Trust Case Control Consortium (WTCCC) GWAS of BD, and the replication cohort comes from the National Institute of Mental Health (NIMH) GWAS of BD in European Ancestry individuals. Epistasis network centrality yields replicated enrichment of Cadherin signaling pathway, whose genes have been hypothesized to have an important role in BD pathophysiology but have not demonstrated enrichment in previous analysis. Other enriched pathways include Wnt signaling, circadian rhythm pathway, axon guidance and neuroactive ligand-receptor interaction. In addition to pathway enrichment, the collective network approach elevates the importance of ANK3, DGKH and ODZ4 for BD susceptibility in the WTCCC GWAS, despite their weak single-locus effect in the data. These results provide evidence that numerous small interactions among common alleles may contribute to the diathesis for BD and demonstrate the importance of including information from the network of gene-gene interactions as well as main effects when prioritizing genes for pathway analysis.


Assuntos
Transtorno Bipolar/genética , Caderinas/genética , Epistasia Genética , Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla/métodos , Algoritmos , Inteligência Artificial , Estudos de Coortes , Predisposição Genética para Doença , Variação Genética , Humanos , Modelos Lineares , Polimorfismo de Nucleotídeo Único
13.
Psychol Med ; 42(2): 345-57, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21798113

RESUMO

BACKGROUND: Major depressive disorder (MDD) is associated with deficits in recalling specific autobiographical memories (AMs). Extensive research has examined the functional anatomical correlates of AM in healthy humans, but no studies have examined the neurophysiological underpinnings of AM deficits in MDD. The goal of the present study was to examine the differences in the hemodynamic response between patients with MDD and controls while they engage in AM recall. METHOD: Participants (12 unmedicated MDD patients; 14 controls) underwent functional magnetic resonance imaging (fMRI) scanning while recalling AMs in response to positive, negative and neutral cue words. The hemodynamic response during memory recall versus performing subtraction problems was compared between MDD patients and controls. Additionally, a parametric linear analysis examined which regions correlated with increasing arousal ratings. RESULTS: Behavioral results showed that relative to controls, the patients with MDD had fewer specific (p=0.013), positive (p=0.030), highly arousing (p=0.036) and recent (p=0.020) AMs, and more categorical (p<0.001) AMs. The blood oxygen level-dependent (BOLD) response in the parahippocampus and hippocampus was higher for memory recall versus subtraction in controls and lower in those with MDD. Activity in the anterior insula was lower for specific AM recall versus subtraction, with the magnitude of the decrement greater in MDD patients. Activity in the anterior cingulate cortex was positively correlated with arousal ratings in controls but not in patients with MDD. CONCLUSIONS: We replicated previous findings of fewer specific and more categorical AMs in patients with MDD versus controls. We found differential activity in medial temporal and prefrontal lobe structures involved in AM retrieval between MDD patients and controls as they engaged in AM recall. These neurophysiological deficits may underlie AM recall impairments seen in MDD.


Assuntos
Córtex Cerebral/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Neuroimagem Funcional/métodos , Memória Episódica , Rememoração Mental/fisiologia , Adulto , Feminino , Neuroimagem Funcional/instrumentação , Hipocampo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Giro Para-Hipocampal/fisiopatologia
15.
Mol Psychiatry ; 16(4): 407-18, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20351719

RESUMO

Genetic variation in the cholinergic muscarinic-2 (M(2)) receptor gene (CHRM2) has been associated with the risk for developing depression. We previously reported that M(2)-receptor distribution volume (V(T)) was reduced in depressed subjects with bipolar disorder (BD) relative to depressed subjects with major depressive disorder (MDD) and healthy controls (HCs). In this study, we investigated the effects of six single-nucleotide polymorphisms (SNPs) for CHRM2 on M(2)-receptor binding to test the hypotheses that genetic variation in CHRM2 influences M(2)-receptor binding and that a CHRM2 polymorphism underlies the deficits in M(2)-receptor V(T) observed in BD. The M(2)-receptor V(T) was measured using positron emission tomography and [(18)F]FP-TZTP in unmedicated, depressed subjects with BD (n=16) or MDD (n=24) and HCs (n=25), and the effect of genotype on V(T) was assessed. In the controls, one SNP (with identifier rs324650, in which the ancestral allele adenine (A) is replaced with one or two copies of thymine (T), showed a significant allelic effect on V(T) in the pregenual and subgenual anterior cingulate cortices in the direction AA

Assuntos
Transtorno Bipolar/genética , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Receptor Muscarínico M2/genética , Receptor Muscarínico M2/metabolismo , Adolescente , Adulto , Transtorno Bipolar/complicações , Transtorno Bipolar/diagnóstico por imagem , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Feminino , Radioisótopos de Flúor , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons/métodos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/genética , Escalas de Graduação Psiquiátrica , Estatísticas não Paramétricas , Adulto Jovem
16.
Neuroscience ; 164(1): 300-30, 2009 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-19358877

RESUMO

Imaging techniques are a potentially powerful method of identifying phenotypes that are associated with, or are indicative of, a vulnerability to developing major depressive disorder (MDD). Here we identify seven promising MDD-associated traits identified by magnetic resonance imaging (MRI) or positron emission tomography (PET). We evaluate whether these traits are state-independent, heritable endophenotypes, or state-dependent phenotypes that may be useful markers of treatment efficacy. In MDD, increased activity of the amygdala in response to negative stimuli appears to be a mood-congruent phenomenon, and is likely moderated by the 5-HT transporter gene (SLC6A4) promoter polymorphism (5-HTTLPR). Hippocampal volume loss is characteristic of elderly or chronically-ill samples and may be impacted by the val66met brain-derived neurotrophic factor (BDNF) gene variant and the 5-HTTLPR SLC6A4 polymorphism. White matter pathology is salient in elderly MDD cohorts but is associated with cerebrovascular disease, and is unlikely to be a useful marker of a latent MDD diathesis. Increased blood flow or metabolism of the subgenual anterior cingulate cortex (sgACC), together with gray matter volume loss in this region, is a well-replicated finding in MDD. An attenuation of the usual pattern of fronto-limbic connectivity, particularly a decreased temporal correlation in amygdala-anterior cingulate cortex (ACC) activity, is another MDD-associated trait. Concerning neuroreceptor PET imaging, decreased 5-HT(1A) binding potential in the raphe, medial temporal lobe, and medial prefrontal cortex (mPFC) has been strongly associated with MDD, and may be impacted by a functional single nucleotide polymorphism in the promoter region of the 5-HT(1A) gene (HTR1A: -1019 C/G; rs6295). Potentially indicative of inter-study variation in MDD etiology or mood state, both increased and decreased binding potential of the 5-HT transporter has been reported. Challenges facing the field include the problem of phenotypic and etiological heterogeneity, technological limitations, the confounding effects of medication, and non-disease related inter-individual variation in brain morphology and function. Further advances are likely as epigenetic, copy-number variant, gene-gene interaction, and genome-wide association (GWA) approaches are brought to bear on imaging data.


Assuntos
Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/fisiopatologia , Fenótipo , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/fisiopatologia , Mapeamento Encefálico , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/patologia , Humanos , Modelos Genéticos , Cintilografia
17.
Mol Psychiatry ; 13(9): 829, 833-57, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18574483

RESUMO

The ability to regulate emotions is an important part of adaptive functioning in society. Advances in cognitive and affective neuroscience and biological psychiatry have facilitated examination of neural systems that may be important for emotion regulation. In this critical review we first develop a neural model of emotion regulation that includes neural systems implicated in different voluntary and automatic emotion regulatory subprocesses. We then use this model as a theoretical framework to examine functional neural abnormalities in these neural systems that may predispose to the development of a major psychiatric disorder characterized by severe emotion dysregulation, bipolar disorder.


Assuntos
Transtorno Bipolar/fisiopatologia , Emoções/fisiologia , Modelos Neurológicos , Neurônios/fisiologia , Animais , Atenção/fisiologia , Mapeamento Encefálico , Cognição/fisiologia , Humanos , Inibição Psicológica , Vias Neurais/fisiologia , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/fisiologia
18.
Psychopharmacology (Berl) ; 196(1): 29-38, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17940752

RESUMO

RATIONALE: The serotonin (5-HT) system is considered important for decision-making. However, its role in reward- and punishment-based processing has not yet been clearly determined. OBJECTIVES: The present study examines the effect of 5-HTTLPR genotype and tryptophan depletion on reward- and punishment-related processing, using a task that considers decision-making in situations of subtlety of choice. Thus, it considers that response choice often occurs in situations where both options are desirable (e.g., choosing between mousse au chocolat or crème caramel cheesecake from a menu) or undesirable. It also considers that response choice is easier when the reinforcements associated with the options are far apart, rather than close, in value. MATERIALS AND METHODS: Healthy volunteers underwent acute tryptophan depletion (ATD) or control procedures and genotyping of the 5-HTTLPR for long and short allele variants. We then examined the effects and interactions of ATD and the serotonin promoter polymorphism genotype on two aspects of decision-making: (a) decision form, choosing between two objects to gain the greater reward or lesser punishment and (b) between-object reinforcement distance, the difference in reinforcements associated with two options. RESULTS: ATD and LL homozygosity had comparable interactions with decision form and between-object reinforcement distance. Specifically, both modulated the effect of between-object reinforcement distance when deciding between objects both associated with punishment. Moreover, ATD and genotype interacted with ATD disproportionately affecting the performance of the LL homozygous group. CONCLUSIONS: These results suggest that serotonin is particularly associated with punishment, rather than reward-related processing, and that individual sensitivity to punishment-related information and tryptophan depletion varies with genotype.


Assuntos
Comportamento de Escolha/fisiologia , Genótipo , Polimorfismo Genético/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Triptofano/fisiologia , Adulto , Alelos , Aminoácidos/administração & dosagem , Cápsulas , Tomada de Decisões/fisiologia , Método Duplo-Cego , Feminino , Jogo de Azar/psicologia , Triagem de Portadores Genéticos , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Reconhecimento Visual de Modelos , Regiões Promotoras Genéticas/genética , Punição , Reforço Psicológico , Triptofano/administração & dosagem
19.
Neuroimage ; 35(1): 430-40, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17239620

RESUMO

In this study, we examined the impact of goal-directed processing on the response to emotional pictures and the impact of emotional pictures on goal-directed processing. Subjects (N=22) viewed neutral or emotional pictures in the presence or absence of a demanding cognitive task. Goal-directed processing disrupted the BOLD response to emotional pictures. In particular, the BOLD response within bilateral amygdala and inferior frontal gyrus decreased during concurrent task performance. Moreover, the presence of both positive and negative distractors disrupted task performance, with reaction times increasing for emotional relative to neutral distractors. Moreover, in line with the suggestion of the importance of lateral frontal regions in emotional regulation [Ochsner, K. N., Ray, R. D., Cooper, J. C., Robertson, E. R., Chopra, S., Gabrieli, J. D., et al. (2004). For better or for worse: neural systems supporting the cognitive down-and up-regulation of negative emotion. NeuroImage, 23(2), 483-499], connectivity analysis revealed positive connectivity between lateral superior frontal cortex and regions of middle frontal cortex previously implicated in emotional suppression [Beauregard, M., Levesque, J., and Bourgouin, P. (2001). Neural correlates of conscious self-regulation of emotion. J. Neurosci., 21 (18), RC165.; Levesque, J., Eugene, F., Joanette, Y., Paquette, V., Mensour, B., Beaudoin, G., et al. (2003). Neural circuitry underlying voluntary suppression of sadness. Biol. Psychiatry, 53 (6), 502-510.; Ohira, H., Nomura, M., Ichikawa, N., Isowa, T., Iidaka, T., Sato, A., et al. (2006). Association of neural and physiological responses during voluntary emotion suppression. NeuroImage, 29 (3), 721-733] and negative connectivity with bilateral amygdala. These data suggest that processes involved in emotional regulation are recruited during task performance in the context of emotional distractors.


Assuntos
Cognição/fisiologia , Emoções/fisiologia , Adulto , Tonsila do Cerebelo/fisiologia , Atenção/fisiologia , Sinais (Psicologia) , Feminino , Fixação Ocular , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Oxigênio/sangue , Estimulação Luminosa , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia
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