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2.
MethodsX ; 7: 101117, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33194564

RESUMO

Anatomically, connections form the fundamental brain network, functionally the different types of oscillatory electric activities are creating a temporarily connected fraction of the anatomical connectome generating an output to the motor system. Schizophrenia can be considered as a connectome disease, in which the sensory input generates a schizophrenia specific temporary connectome and the signal processing becomes diseased showing hallucinations and adverse behavioral reactions. In this work, flexible, 32-channel polymer microelectrode arrays fabricated by the authors are used to map the functional coherence on large cortical areas during physiological activities in a schizophrenia model in rats.-Fabrication of a flexible microECoG array is shown.-Protocol to use a flexible microECoG is demonstrated to characterize connectome diseases in rats.-Customized method to analyze the functional coherence between different cortical areas during visually evoked potential is detailed.-R-based implementation of the analysis method is presented.

3.
J Affect Disord ; 274: 515-521, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32663984

RESUMO

BACKGROUND: Personality traits are risk and protective factors in affective disorders. However, few studies have investigated the role of narrow personality facets, with existing research yielding contradictory results. Previous research has mostly focused on simple correlations. Several studies have performed separate multiple regressions within each trait, and have used non-standard measures of personality, making it difficult to determine how individual facets make unique contributions. METHOD: This study performed secondary analysis of the NewMood data set (collected 2004-2009), comprising 264 participants from Greater Manchester. Participants provided self-reports of all NEO-PI-R personality facets, and semi-structured questionnaires of clinical depression and anxiety. All personality facets were entered into multiple regressions to explain variance in depression and anxiety. RESULTS: Variance in both anxiety and depression were explained by a small number of personality facets, namely facet depression (referring to demotivation), facets positive emotion and assertiveness in extroversion, and facet competence in conscientiousness. LIMITATIONS: This study relies on cross-sectional data and cannot determine causation. This study uses a mostly female sample, and the results were not stratified by sex due to the small sample. CONCLUSION: Previous studies suggest that broad trait neuroticism positively associates with affective disorders; this study adds that the effect of neuroticism is limited to facet depression (related to demotivation). Contrary to previous studies, no facet of agreeableness or openness explained variance in affective disorders, and facet assertiveness positively associated with affective disorder scores. These findings may help to improve treatment matching and explain the mechanisms through which affective disorders develop.


Assuntos
Depressão , Personalidade , Ansiedade , Estudos Transversais , Feminino , Humanos , Neuroticismo , Inventário de Personalidade
4.
Biol Futur ; 71(4): 427-434, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34554464

RESUMO

4-aminopyridine (4-AP) is a widely used drug that induces seizure activity in rodents, especially in rats, although there is no consensus in the literature on the dose to be used in mice. The aim of the present study was to investigate the effect of the intraperitoneal administration of 4-AP in two doses (4 and 10 mg/kg) in vivo. EEG, movement, and video recordings were made simultaneously in male B6 mice to specify the details of the seizures and to determine whether there is a suitable non-lethal dose for seizure induction and for further molecular studies. Seizure behavior in mice differs from that seen in rats, with no characteristic stages of epileptic seizures, but with spiking and seizure activity. Seizure activity, although produced at both doses without being lethal, induced different changes of the EEG pattern. Smaller dose induced a lower amplitude seizure activity, decreased spiking activity and later onset of seizures, while higher dose induced a much more intense brain seizure activity and severe trembling. It is concluded that the intraperitoneal administration of 4-AP at a dose of 10 mg/kg induces explicit seizure activity in mice which is repeatable and can be suitable for further molecular research.


Assuntos
4-Aminopiridina/efeitos adversos , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Epilepsia/etiologia , Animais , Modelos Animais de Doenças , Camundongos , Bloqueadores dos Canais de Potássio/efeitos adversos
5.
Mol Psychiatry ; 23(1): 133-142, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28373689

RESUMO

The hypothesis that the S allele of the 5-HTTLPR serotonin transporter promoter region is associated with increased risk of depression, but only in individuals exposed to stressful situations, has generated much interest, research and controversy since first proposed in 2003. Multiple meta-analyses combining results from heterogeneous analyses have not settled the issue. To determine the magnitude of the interaction and the conditions under which it might be observed, we performed new analyses on 31 data sets containing 38 802 European ancestry subjects genotyped for 5-HTTLPR and assessed for depression and childhood maltreatment or other stressful life events, and meta-analysed the results. Analyses targeted two stressors (narrow, broad) and two depression outcomes (current, lifetime). All groups that published on this topic prior to the initiation of our study and met the assessment and sample size criteria were invited to participate. Additional groups, identified by consortium members or self-identified in response to our protocol (published prior to the start of analysis) with qualifying unpublished data, were also invited to participate. A uniform data analysis script implementing the protocol was executed by each of the consortium members. Our findings do not support the interaction hypothesis. We found no subgroups or variable definitions for which an interaction between stress and 5-HTTLPR genotype was statistically significant. In contrast, our findings for the main effects of life stressors (strong risk factor) and 5-HTTLPR genotype (no impact on risk) are strikingly consistent across our contributing studies, the original study reporting the interaction and subsequent meta-analyses. Our conclusion is that if an interaction exists in which the S allele of 5-HTTLPR increases risk of depression only in stressed individuals, then it is not broadly generalisable, but must be of modest effect size and only observable in limited situations.


Assuntos
Depressão/genética , Depressão/psicologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Estresse Psicológico/complicações , Comportamento Cooperativo , Interação Gene-Ambiente , Predisposição Genética para Doença , Genótipo , Humanos , Acontecimentos que Mudam a Vida , Estresse Psicológico/genética
6.
Genes Brain Behav ; 16(3): 384-393, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27762084

RESUMO

One of the main effects of the endocannabinoid system in the brain is stress adaptation with presynaptic endocannabinoid receptor 1 (CB1 receptors) playing a major role. In the present study, we investigated whether the effect of the CB1 receptor coding CNR1 gene on migraine and its symptoms is conditional on life stress. In a cross-sectional European population (n = 2426), recruited from Manchester and Budapest, we used the ID-Migraine questionnaire for migraine screening, the Life Threatening Experiences questionnaire to measure recent negative life events (RLE), and covered the CNR1 gene with 11 SNPs. The main genetic effects and the CNR1 × RLE interaction with age and sex as covariates were tested. None of the SNPs showed main genetic effects on possible migraine or its symptoms, but 5 SNPs showed nominally significant interaction with RLE on headache with nausea using logistic regression models. The effect of rs806366 remained significant after correction for multiple testing and replicated in the subpopulations. This effect was independent from depression- and anxiety-related phenotypes. In addition, a Bayesian systems-based analysis demonstrated that in the development of headache with nausea all SNPs were more relevant with higher a posteriori probability in those who experienced recent life stress. In summary, the CNR1 gene in interaction with life stress increased the risk of headache with nausea suggesting a specific pathological mechanism to develop migraine, and indicating that a subgroup of migraine patients, who suffer from life stress triggered migraine with frequent nausea, may benefit from therapies that increase the endocannabinoid tone.


Assuntos
Cefaleia/genética , Náusea/genética , Receptor CB1 de Canabinoide/genética , Estresse Psicológico/genética , Estresse Psicológico/psicologia , Adulto , Estudos Transversais , Endocanabinoides/genética , Endocanabinoides/metabolismo , Feminino , Predisposição Genética para Doença , Variação Genética , Cefaleia/psicologia , Humanos , Masculino , Transtornos de Enxaqueca/genética , Transtornos de Enxaqueca/metabolismo , Transtornos de Enxaqueca/psicologia , Náusea/psicologia , Polimorfismo de Nucleotídeo Único , Receptor CB1 de Canabinoide/metabolismo , Estresse Psicológico/metabolismo , Inquéritos e Questionários , População Branca/genética
7.
Transl Psychiatry ; 6(11): e945, 2016 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-27824360

RESUMO

Current understanding and treatment of depression is limited to the monoaminergic theory with little knowledge of the involvement of other cellular processes. Genome-wide association studies, however, implicate several novel single-nucleotide polymorphisms with weak but replicable effects and unclarified mechanisms. We investigated the effect of rs1106634 of the ATPV1B2 gene encoding the vacuolar H+ATPase on lifetime and current depression and the possible mediating role of neuroticism by logistic and linear regression in a white European general sample of 2226 subjects. Association of rs1106634 with performance on frontal (Stockings of Cambridge (SOC)) and hippocampal-dependent (paired associates learning (PAL)) cognitive tasks was investigated in multivariate general linear models in a smaller subsample. The ATP6V1B2 rs1106634 A allele had a significant effect on lifetime but not on current depression. The effect of the A allele on lifetime depression was not mediated by neuroticism. The A allele influenced performance on the PAL but not on the SOC test. We conclude that the effects of variation in the vacuolar ATPase may point to a new molecular mechanism that influences the long-term development of depression. This mechanism may involve dysfunction specifically in hippocampal circuitry and cognitive impairment that characterizes recurrent and chronic depression.


Assuntos
Alelos , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/fisiopatologia , Genética , Hipocampo/fisiopatologia , Transtornos Neurocognitivos/genética , Transtornos Neurocognitivos/fisiopatologia , Medição de Risco , Adulto , Estudos de Coortes , Feminino , Lobo Frontal/fisiopatologia , Humanos , Masculino , Rede Nervosa/fisiopatologia , Testes Neuropsicológicos/estatística & dados numéricos , Neuroticismo/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Psicometria , ATPases Vacuolares Próton-Translocadoras
8.
Transl Psychiatry ; 6: e798, 2016 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-27138797

RESUMO

Several studies indicate that 5-HTTLPR mediates the effect of childhood adversity in the development of depression, while results are contradictory for recent negative life events. For childhood adversity the interaction with genotype is strongest for sexual abuse, but not for other types of childhood maltreatment; however, possible interactions with specific recent life events have not been investigated separately. The aim of our study was to investigate the effect of four distinct types of recent life events in the development of depressive symptoms in a large community sample. Interaction between different types of recent life events measured by the List of Threatening Experiences and the 5-HTTLPR genotype on current depression measured by the depression subscale and additional items of the Brief Symptom Inventory was investigated in 2588 subjects in Manchester and Budapest. Only a nominal interaction was found between life events overall and 5-HTTLPR on depression, which failed to survive correction for multiple testing. However, subcategorising life events into four categories showed a robust interaction between financial difficulties and the 5-HTTLPR genotype, and a weaker interaction in the case of illness/injury. No interaction effect for the other two life event categories was present. We investigated a general non-representative sample in a cross-sectional approach. Depressive symptoms and life event evaluations were self-reported. The 5-HTTLPR polymorphism showed a differential interaction pattern with different types of recent life events, with the strongest interaction effects of financial difficulties on depressive symptoms. This specificity of interaction with only particular types of life events may help to explain previous contradictory findings.


Assuntos
Transtorno Depressivo/genética , Transtorno Depressivo/psicologia , Acontecimentos que Mudam a Vida , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Fatores Socioeconômicos , Estresse Psicológico/psicologia , Adolescente , Transtorno Depressivo/etiologia , Feminino , Humanos , Hungria , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético/genética , Fatores de Risco , Estresse Psicológico/complicações , Estresse Psicológico/genética , Reino Unido , Adulto Jovem
9.
J Neural Eng ; 13(2): 026025, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26924827

RESUMO

OBJECTIVE: Exploring neural activity behind synchronization and time locking in brain circuits is one of the most important tasks in neuroscience. Our goal was to design and characterize a microelectrode array (MEA) system specifically for obtaining in vivo extracellular recordings from three deep-brain areas of freely moving rats, simultaneously. The target areas, the deep mesencephalic reticular-, pedunculopontine tegmental-and pontine reticular nuclei are related to the regulation of sleep-wake cycles. APPROACH: The three targeted nuclei are collinear, therefore a single-shank MEA was designed in order to contact them. The silicon-based device was equipped with 3 × 4 recording sites, located according to the geometry of the brain regions. Furthermore, a microdrive was developed to allow fine actuation and post-implantation relocation of the probe. The probe was attached to a rigid printed circuit board, which was fastened to the microdrive. A flexible cable was designed in order to provide not only electronic connection between the probe and the amplifier system, but sufficient freedom for the movements of the probe as well. MAIN RESULTS: The microdrive was stable enough to allow precise electrode targeting into the tissue via a single track. The microelectrodes on the probe were suitable for recording neural activity from the three targeted brainstem areas. SIGNIFICANCE: The system offers a robust solution to provide long-term interface between an array of precisely defined microelectrodes and deep-brain areas of a behaving rodent. The microdrive allowed us to fine-tune the probe location and easily scan through the regions of interest.


Assuntos
Tronco Encefálico/fisiologia , Espectroscopia Dielétrica/métodos , Locomoção/fisiologia , Microeletrodos , Monitorização Ambulatorial/métodos , Silício , Animais , Movimento/fisiologia , Ratos , Ratos Sprague-Dawley , Silício/química
10.
Transl Psychiatry ; 6: e745, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26926881

RESUMO

Alterations in the folate pathway have been related to both major depression and cognitive inflexibility; however, they have not been investigated in the genetic background of ruminative response style, which is a form of perseverative cognition and a risk factor for depression. In the present study, we explored the association of rumination (measured by the Ruminative Responses Scale) with polymorphisms of two distinct folate pathway genes, MTHFR rs1801133 (C677T) and MTHFD1L rs11754661, in a combined European white sample from Budapest, Hungary (n=895) and Manchester, United Kingdom (n=1309). Post hoc analysis investigated whether the association could be replicated in each of the two samples, and the relationship between folate pathway genes, rumination, lifetime depression and Brief Symptom Inventory depression score. Despite its functional effect on folate metabolism, the MTHFR rs1801133 showed no effect on rumination. However, the A allele of MTHFD1L rs11754661 was significantly associated with greater rumination, and this effect was replicated in both the Budapest and Manchester samples. In addition, rumination completely mediated the effects of MTHFD1L rs11754661 on depression phenotypes. These findings suggest that the MTHFD1L gene, and thus the C1-THF synthase enzyme of the folate pathway localized in mitochondria, has an important effect on the pathophysiology of depression through rumination, and maybe via this cognitive intermediate phenotype on other mental and physical disorders. Further research should unravel whether the reversible metabolic effect of MTHFD1L is responsible for increased rumination or other long-term effects on brain development.


Assuntos
Aminoidrolases/genética , Transtornos Cognitivos/complicações , Transtornos Cognitivos/genética , Transtorno Depressivo/complicações , Transtorno Depressivo/genética , Formiato-Tetra-Hidrofolato Ligase/genética , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Complexos Multienzimáticos/genética , Adulto , Feminino , Ácido Fólico , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco
11.
Neuroscience ; 300: 593-608, 2015 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-26037802

RESUMO

Adenosine (Ado) and non-adenosine (non-Ado) nucleosides such as inosine (Ino), guanosine (Guo) and uridine (Urd) may have regionally different roles in the regulation of physiological and pathophysiological processes in the central nervous system (CNS) such as epilepsy. It was demonstrated previously that Ino and Guo decreased quinolinic acid (QA)-induced seizures and Urd reduced penicillin-, bicuculline- and pentylenetetrazole (PTZ)-induced seizures. It has also been demonstrated that Ino and Urd may exert their effects through GABAergic system by altering the function of GABA(A) type of gamma-aminobutyric acid receptors (GABAA receptors) whereas Guo decreases glutamate-induced excitability through glutamatergic system, which systems (GABAergic and glutamatergic) are involved in pathomechanisms of absence epilepsy. Thus, we hypothesized that Ino and Guo, similarly to the previously described effect of Urd, might also decrease absence epileptic activity. We investigated in the present study whether intraperitoneal (i.p.) application of Ino (500 and 1000mg/kg), Guo (20 and 50mg/kg), Urd (500 and 1000mg/kg), GABA(A) receptor agonist muscimol (1 and 3mg/kg), GABA(A) receptor antagonist bicuculline (2 and 4mg/kg), non-selective Ado receptor antagonist theophylline (5 and 10mg/kg) and non-competitive N-methyl-d-aspartate (NMDA) receptor antagonist (+)-5-methyl-10,11-dihydro-5H-dibenzo (a,d) cyclohepten-5,10-imine maleate (MK-801, 0.0625 and 0.1250mg/kg) alone and in combination have modulatory effects on absence epileptic activity in Wistar Albino Glaxo Rijswijk (WAG/Rij) rats. We found that Guo decreased the number of spike-wave discharges (SWDs) whereas Ino increased it dose-dependently. We strengthened that Urd can decrease absence epileptic activity. Our results suggest that Guo, Urd and their analogs could be potentially effective drugs for treatment of human absence epilepsy.


Assuntos
Anticonvulsivantes/farmacologia , Encéfalo/efeitos dos fármacos , Epilepsia Tipo Ausência/tratamento farmacológico , Guanosina/farmacologia , Inosina/farmacologia , Uridina/farmacologia , Animais , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Eletrocorticografia , Epilepsia Tipo Ausência/fisiopatologia , Masculino , Ratos Wistar , Receptores de GABA-A/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores Purinérgicos P1/metabolismo
12.
Psychol Med ; 45(6): 1301-13, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25300570

RESUMO

BACKGROUND: Prosocial emotions related to self-blame are important in guiding human altruistic decisions. These emotions are elevated in major depressive disorder (MDD), such that MDD has been associated with guilt-driven pathological hyper-altruism. However, the impact of such emotional impairments in MDD on different types of social decision-making is unknown. METHOD: In order to address this issue, we investigated different kinds of altruistic behaviour (interpersonal cooperation and fund allocation, altruistic punishment and charitable donation) in 33 healthy subjects, 35 patients in full remission (unmedicated) and 24 currently depressed patients (11 on medication) using behavioural-economical paradigms. RESULTS: We show a significant main effect of clinical status on altruistic decisions (p = 0.04) and a significant interaction between clinical status and type of altruistic decisions (p = 0.03). More specifically, symptomatic patients defected significantly more in the Prisoner's Dilemma game (p < 0.05) and made significantly lower charitable donations, whether or not these incurred a personal cost (p < 0.05 and p < 0.01, respectively). Currently depressed patients also reported significantly higher guilt elicited by receiving unfair financial offers in the Ultimatum Game (p < 0.05). CONCLUSIONS: Currently depressed individuals were less altruistic in both a charitable donation and an interpersonal cooperation task. Taken together, our results challenge the guilt-driven pathological hyper-altruism hypothesis in depression. There were also differences in both current and remitted patients in the relationship between altruistic behaviour and pathological self-blaming, suggesting an important role for these emotions in moral and social decision-making abnormalities in depression.


Assuntos
Altruísmo , Comportamento Cooperativo , Tomada de Decisões/fisiologia , Transtorno Depressivo Maior/fisiopatologia , Culpa , Princípios Morais , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Curr Med Chem ; 21(6): 788-821, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24251559

RESUMO

Despite newly developed antiepileptic drugs to suppress epileptic symptoms, approximately one third of patients remain drug refractory. Consequently, there is an urgent need to develop more effective therapeutic approaches to treat epilepsy. A great deal of evidence suggests that endogenous nucleosides, such as adenosine (Ado), guanosine (Guo), inosine (Ino) and uridine (Urd), participate in the regulation of pathomechanisms of epilepsy. Adenosine and its analogues, together with non-adenosine (non-Ado) nucleosides (e.g., Guo, Ino and Urd), have shown antiseizure activity. Adenosine kinase (ADK) inhibitors, Ado uptake inhibitors and Ado-releasing implants also have beneficial effects on epileptic seizures. These results suggest that nucleosides and their analogues, in addition to other modulators of the nucleoside system, could provide a new opportunity for the treatment of different types of epilepsies. Therefore, the aim of this review article is to summarize our present knowledge about the nucleoside system as a promising target in the treatment of epilepsy.


Assuntos
Anticonvulsivantes/farmacologia , Epilepsia/tratamento farmacológico , Nucleosídeos/metabolismo , Animais , Anticonvulsivantes/uso terapêutico , Humanos , Terapia de Alvo Molecular
14.
Curr Med Chem ; 21(6): 764-87, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24251562

RESUMO

Neuropeptides are signaling molecules participating in the modulation of synaptic transmission. Neuropeptides are stored in dense core synaptic vesicles, the release of which requires profound excitation. Only in the extracellular space, neuropeptides act on G-protein coupled receptors to exert a relatively slow action both pre- and postsynaptically. Consequently, neuropeptide modulators are ideal candidates to influence epileptic tissue overexcited during seizures. Indeed, a number of neuropeptides have receptors implicated in epilepsy and many of them are considered to participate in endogenous neuroprotective actions. Neuropeptide receptors, present in the hippocampus, the most frequent focus of seizures in temporal lobe epilepsy, received the largest attention as potential anti-epileptic targets. Receptors of hippocampal neuropeptides, somatostatin, neuropeptide Y, galanin, dynorphin, enkephalin, substance P, cholecystokinin, vasoactive intestinal polypeptide, and receptors of some neuropeptides, which are also hormones such as ghrelin, angiotensins, corticotropin- releasing hormone, adrenocorticotropin, thyrotropin-releasing hormone, oxytocin and vasopressin involved in epilepsy are discussed in the review article. Activation and inhibition of receptors by oral application of peptides as drugs is typically not efficient because of low bioavailability: rapid degradation and insufficient penetration of peptides through the blood-brain barrier. Recent progress in the development of non-peptide agonists and antagonists of neuropeptide receptors as well as gene therapeutic approaches leading to the local production of agonists and antagonists within the central nervous system will also be discussed.


Assuntos
Epilepsia/metabolismo , Epilepsia/terapia , Receptores de Neuropeptídeos/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Humanos , Terapia de Alvo Molecular , Neuropeptídeos/metabolismo
15.
Psychol Med ; 44(9): 1825-34, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24176142

RESUMO

BACKGROUND: Major depressive disorder (MDD) is associated with abnormalities in financial reward processing. Previous research suggests that patients with MDD show reduced sensitivity to frequency of financial rewards. However, there is a lack of conclusive evidence from studies investigating the evaluation of financial rewards over time, an important aspect of reward processing that influences the way people plan long-term investments. Beck's cognitive model posits that patients with MDD hold a negative view of the future that may influence the amount of resources patients are willing to invest into their future selves. METHOD: We administered a delay discounting task to 82 participants: 29 healthy controls, 29 unmedicated participants with fully remitted MDD (rMDD) and 24 participants with current MDD (11 on medication). RESULTS: Patients with current MDD, relative to remitted patients and healthy subjects, discounted large-sized future rewards at a significantly higher rate and were insensitive to changes in reward size from medium to large. There was a main effect of clinical group on discounting rates for large-sized rewards, and discounting rates for large-sized rewards correlated with severity of depressive symptoms, particularly hopelessness. CONCLUSIONS: Higher discounting of delayed rewards in MDD seems to be state dependent and may be a reflection of depressive symptoms, specifically hopelessness. Discounting distant rewards at a higher rate means that patients are more likely to choose immediate financial options. Such impairments related to long-term investment planning may be important for understanding value-based decision making in MDD, and contribute to ongoing functional impairment.


Assuntos
Desvalorização pelo Atraso/fisiologia , Transtorno Depressivo Maior/fisiopatologia , Recompensa , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Mol Psychiatry ; 18(12): 1265-72, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23128153

RESUMO

Reduced hippocampal volume has been reported in depression and may be involved in the aetiology of depressive symptoms and vulnerability to depressive relapse. Neuroplasticity following antidepressant drug treatment in the hippocampus has been demonstrated in animal models but adaptive changes after such treatment have not been shown in humans. In this study, we determined whether grey matter loss in the hippocampus in depression (1) is present in medication-free depressed (2) changes in response to antidepressant treatment and (3) is present as a stable trait in medication-free remitted patients. Sixty-four medication-free unipolar depressed patients: 39 currently depressed and 25 in remission, and 66 healthy controls (HC) underwent structural magnetic resonance imaging in a cross-sectional and longitudinal design. Thirty-two currently depressed participants were then treated with the antidepressant citalopram for 8 weeks. Adherence to treatment was evaluated by measuring plasma citalopram concentration. We measured regional variation in grey matter concentration by using voxel-based morphometry-Diffeomorphic Anatomical Registration Through Exponentiated Lie algebra. Patients with current depression had bilaterally reduced grey matter in the hippocampus compared with HC and untreated patients in stable remission with the latter groups not differing. An increase in grey matter was observed in the hippocampus following treatment with citalopram in currently depressed patients. Grey matter reduction in the hippocampus appears specific to the depressed state and is a potential biomarker for a depressive episode.


Assuntos
Depressão/patologia , Hipocampo/patologia , Adulto , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Estudos de Casos e Controles , Citalopram/farmacologia , Citalopram/uso terapêutico , Estudos Transversais , Depressão/tratamento farmacológico , Depressão/psicologia , Feminino , Hipocampo/efeitos dos fármacos , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico
17.
Psychol Med ; 41(9): 1845-55, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21306660

RESUMO

BACKGROUND: Both past depressive episodes and the personality trait of depressive rumination are strong risk factors for future depression. Depression is associated with abnormal emotional processing, which may be a neurobiological marker for vulnerability to depression. A consistent picture has yet to emerge as to how a history of depression and the tendency to ruminate influence emotional processing. The aim of this study was to investigate the relationship between rumination, past depression and neural responses when processing face emotions. METHOD: The Ruminative Responses Scale (RRS) was completed by 30 remitted depressives and 37 controls who underwent functional magnetic resonance imaging (fMRI) scanning while viewing happy, sad, fearful and neutral faces. RESULTS: The remitted depressives showed overall reductions in neural responses to negative emotions relative to the controls. However, in the remitted depressives, but not the controls, RRS scores were correlated with increased neural responses to negative emotions and decreased responses to happiness in limbic regions. CONCLUSIONS: Automatic emotion processing biases and rumination seem to be correlated to aspects of vulnerability to depression. However, remission from depression may be maintained by a general suppression of limbic responsiveness to negative emotion.


Assuntos
Transtorno Depressivo/psicologia , Emoções , Expressão Facial , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Processos Mentais , Vias Neurais/fisiopatologia , Fatores de Risco
18.
Eur Neuropsychopharmacol ; 21(1): 3-10, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21030216

RESUMO

This study aimed to identify whether genetic manipulation of four systems implicated in the pathogenesis of depression converge on shared molecular processes underpinning depression-like behaviour in mice. Altered 5HT function was modelled using the 5-HT transporter knock out mouse, impaired glucocorticoid receptor (GR) function using an antisense-induced knock down mouse, disrupted glutamate function using a heterozygous KO of the vesicular glutamate transporter 1 gene, and impaired cannabinoid signalling using the cannabinoid 1 receptor KO mouse. All 4 four genetically modified mice were previously shown to show exaggerated helpless behaviour compared to wild-type controls and variable degrees of anxiety and anhedonic behaviour. mRNA was extracted from frontal cortex and hybridised to Illumina microarrays. Combined contrast analysis was used to identify genes showing different patterns of up- and down-regulation across the 4 models. 1823 genes were differentially regulated. They were over-represented in gene ontology categories of metabolism, protein handling and synapse. In each model compared to wild-type mice of the same genetic background, a number of genes showed increased expression changes of >10%, other genes showed decreases in each model. Most of the genes showed mixed effects. Several previous array findings were replicated. The results point to cellular stress and changes in post-synaptic remodelling as final common mechanisms of depression and resilience.


Assuntos
Depressão/genética , Transtorno Depressivo/genética , Lobo Frontal/metabolismo , Regulação da Expressão Gênica , Animais , Ansiedade/genética , Depressão/metabolismo , Transtorno Depressivo/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transtornos do Humor/genética , Prazer/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Proteína Vesicular 1 de Transporte de Glutamato/genética , Proteína Vesicular 1 de Transporte de Glutamato/metabolismo
19.
Br J Pharmacol ; 160(1): 20-35, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20331608

RESUMO

Although nitrate therapy, used in the treatment of cardiovascular disorders, is frequently associated with side-effects, mainly headaches, the summaries of product characteristics of nitrate-containing medicines do not report detailed description of headaches and even do not highlight the possibility of nitrate-induced migraine. Two different types of nitrate-induced headaches have been described: (i) immediate headaches that develop within the first hour of the application, are mild or medium severity without characteristic symptoms for migraine, and ease spontaneously; and (ii) delayed, moderate or severe migraine-type headaches (occurring mainly in subjects with personal or family history of migraine), that develop 3-6 h after the intake of nitrates, with debilitating, long-lasting symptoms including nausea, vomiting, photo- and/or phono-phobia. These two types of headaches are remarkably different, not only in their timing and symptoms, but also in the persons who are at risk. Recent studies provide evidence that the two headache types are caused by different mechanisms: immediate headaches are connected to vasodilation caused by nitric oxide (NO) release, while migraines are triggered by other actions such as the release of calcitonin gene-related peptide or glutamate, or changes in ion channel function mediated by cyclic guanosine monophosphate or S-nitrosylation. Migraines usually need anti-attack medication, such as triptans, but these drugs are contraindicated in most medical conditions that are treated using nitrates. In conclusion, these data recommend the correction of summaries of nitrate product characteristics, and also suggest a need to develop new types of anti-migraine drugs, effective in migraine attacks, that could be used in patients with risk for angina pectoris.


Assuntos
Transtornos da Cefaleia/induzido quimicamente , Transtornos de Enxaqueca/induzido quimicamente , Doadores de Óxido Nítrico/efeitos adversos , Vasodilatação/efeitos dos fármacos , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Ciclo-Oxigenase 2/metabolismo , Tolerância a Medicamentos , Predisposição Genética para Doença , Transtornos da Cefaleia/tratamento farmacológico , Transtornos da Cefaleia/fisiopatologia , Humanos , Canais Iônicos/metabolismo , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/fisiopatologia , Prostaglandinas/metabolismo , Fatores de Risco , Serotonina/metabolismo , Fatores de Tempo
20.
Prog Neuropsychopharmacol Biol Psychiatry ; 32(8): 1782-8, 2008 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-18721843

RESUMO

OBJECTIVE: The cyclic nature of female reproductive function is a natural part of life accompanied by changes in several physical and psychological phenomena. The aim of our study was to investigate the fluctuation of psychological symptoms throughout the female reproductive cycle in healthy, non-PMDD (premenstrual dysphoric disorder) women. METHOD: 63 psychiatrically healthy, non-PMDD women with normal regular menstrual cycles and not using hormonal contraceptive methods participated in the study. Participants completed the PRISM (Prospective Record of the Impact and Severity of Menstrual Symptoms) calendar every night for three cycles and in addition they completed several other psychometric measures (Symptom Distress Checklist-SCL-51, State Trait Anxiety Inventory-STAI, Zung Self-rating Depression Scale-ZSDS, Eating Attitude Test-EAT, Mind and Body Cathexis Scale) at three predefined days of the first cycle. Based on an at least 66% increase in physical symptoms from the late follicular to the late luteal phase on the PRISM, subjects were assigned to luteal phase physical symptoms (LPPS) and no luteal phase physical symptoms (nonLPPS) groups. The association of psychometric scores with timing within the cycle and with physical symptoms was analysed. RESULTS: Significant changes in psychometric scores over time were observed for STAI state anxiety, SCL anxiety, SCL somatization, SCL depression, SCL obsessive-compulsive, SCL interpersonal sensitivity, SCL total, and ZSDS. A significant timexLPPS grouping interaction emerged in case of the SCL somatization subscale and the ZSDS. LPPS grouping was associated with only the interpersonal sensitivity subscale of the SCL51. CONCLUSION: Our results indicate that there is a significant increase in psychological symptoms related to neuroticism and depression from the late follicular to the late luteal phase in a healthy, non-PMDD female population. Although our results may not have direct clinical significance, since the statistically significant increases in psychometric scores are still small, it is an important finding that there is a consistent pattern observable in the fluctuation of psychological symptoms accompanying the female reproductive cycle.


Assuntos
Afeto/fisiologia , Ciclo Menstrual/fisiologia , Ciclo Menstrual/psicologia , Síndrome Pré-Menstrual/diagnóstico , Adolescente , Adulto , Análise de Variância , Feminino , Humanos , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Psicometria , Fatores de Tempo , Adulto Jovem
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