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Brain-derived neurotrophic factor (BDNF) is the most abundant brain neurotrophin and plays a critical role in neuronal growth, survival and plasticity, implicated in the pathophysiology of Bipolar Disorders (BD). The single-nucleotide polymorphism in the BDNF gene (BDNF rs6265) has been associated with decreased hippocampal BDNF secretion and volume in met carriers in different populations, although the val allele has been reported to be more frequent in BD patients. The anterior cingulate cortex (ACC) is a key center integrating cognitive and affective neuronal connections, where consistent alterations in brain metabolites such as Glx (Glutamate + Glutamine) and N-acetylaspartate (NAA) have been consistently reported in BD. However, little is known about the influence of BDNF rs6265 on neurochemical profile in the ACC of Healthy Controls (HC) and BD subjects. The aim of this study was to assess the influence of BDNF rs6265 on ACC neurometabolites (Glx, NAA and total creatine- Cr) in 124 euthymic BD type I patients and 76 HC, who were genotyped for BDNF rs6265 and underwent a 3-Tesla proton magnetic resonance imaging and spectroscopy scan (1 H-MRS) using a PRESS ACC single-voxel (8cm3) sequence. BDNF rs6265 polymorphism showed a significant two-way interaction (diagnosis × genotype) in relation to NAA/Cr and total Cr. While met carriers presented increased NAA/Cr in HC, BD-I subjects with the val allele revealed higher total Cr, denoting an enhanced ACC metabolism likely associated with increased glutamatergic metabolites observed in BD-I val carriers. However, these results were replicated only in men. Therefore, our results support evidences that the BDNF rs6265 polymorphism exerts a complex pleiotropic effect on ACC metabolites influenced by the diagnosis and sex.

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OBJECTIVE: To conduct a systematic review and meta-analysis of the effects of antidepressant drug therapy (with or without physical exercise) on peripheral inflammatory markers in patients with major depressive disorder (MDD). METHODS: MEDLINE, PyscINFO, Embase, and Google Scholar databases were searched until May 2020. Randomized trials that measured at least one inflammatory biomarker and included adult outpatients with MDD under antidepressant drug therapy (any drug) with or without physical exercise (any modality) were eligible. Results were summarized using the standardized mean difference (SMD) with 95% confidence intervals (95% CI) under a random-effects model. The Cochrane risk of bias tool (2010) was used to evaluate the risk of bias in the included trials. RESULTS: Sixty-three trials were identified, encompassing data from 3482 patients, and 20 investigated biomarkers. Trials had biases across multiple domains, rising concerns primarily to selection bias/performance bias/detection bias/attrition bias. SMDs between pre- and post-results indicated a significant reduction in the levels of IL-2 (SMD, - 0.25; 95% CI, - 0.41 to - 0.09, P = 0.002), IL-6 (SMD, - 0.19; 95% CI, - 0.35 to - 0.025, P = 0.024), IL-10 (SMD, - 0.32; 95% CI, - 0.57 to - 0.07, P = 0.011), and serum cortisol (SMD, - 0.35; 95% CI, - 0.58 to - 0.12, P = 0.002). Evidence supporting the influence of physical exercise combined with antidepressant drugs on peripheral inflammatory markers in MDD is sparse and heterogeneous. CONCLUSION: There is some evidence that antidepressant drug therapy is associated with an overall positive reduction in inflammatory markers, but the evidence is heterogeneous. Further research linking how inflammatory biomarkers modulate physiology related to antidepressant response is required. TRIAL REGISTRATION: CRD42020220735.

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BACKGROUND: Childhood abuse (CA) is a risk factor for a number of psychiatric disorders and has been associated with higher risk of developing bipolar disorders (BD). CA in BD has been associated with more severe clinical outcomes, but the neurobiological explanation for this is unknown. Few studies have explored in vivo measurement of brain metabolites using proton magnetic resonance spectroscopy (1H-MRS) in CA and no studies have investigated the association of CA severity with brain neurometabolites in BD. OBJECTIVE: To investigate whether CA severity is associated with changes in anterior cingulate cortex (ACC) neurometabolite profile in BD and HC subjects. METHODS: Fifty-nine BD I euthymic patients and fifty-nine HC subjects were assessed using the Childhood Trauma Questionnaire (CTQ) and underwent a 3-Tesla 1H-MRS scan. Severity of childhood abuse (physical, sexual and emotional) and its association with levels of brain metabolites was analyzed within each group. RESULTS: BD patients had higher total scores on the CTQ and higher severity rates of sexual and physical abuse compared to HC subjects. Greater severity of physical and sexual abuse was associated with increased ACC PCr level and lower Cr/PCr ratio in the BD group only. CONCLUSION: Sexual and physical abuse in BD patients, but not in HC subjects, appeared to be associated with creatine metabolism in the ACC, which can influence neuronal mitochondrial energy production. Further studies should investigate whether this is the mechanism underlying the association between CA and worse clinical outcomes in BD.

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Bipolar disorder (BD) is characterized by unstable mood states ranging from mania to depression. Although there is some evidence that mood instability may result from an imbalance between excitatory glutamatergic and inhibitory GABA-ergic neurotransmission, few proton magnetic resonance spectroscopy (1H-MRS) studies have measured these two neurometabolites simultaneously in BD. The enzyme glutamic acid decarboxylase (GAD1) catalyzes the decarboxylation of glutamate (Glu) to GABA, and its single nucleotide polymorphisms (SNPs) might influence Glu/GABA ratio. Thus, we investigated Glu/GABA ratio in the dorsal anterior cingulate cortex (dACC) of euthymic BD type I patients and healthy controls (HC), and assessed the influence of both mood stabilizers and GAD1 SNPs on this ratio. Eighty-eight subjects (50 euthymic BD type I patients and 38 HC) underwent 3T 1H-MRS in the dACC (2 × 2 × 4.5 cm3) using a two-dimensional JPRESS sequence and all subjects were genotyped for 4 SNPs in the GAD1 gene. BD patients had lower dACC Glu/GABA ratio compared to HC, where this was influenced by anticonvulsant and antipsychotic medications, but not lithium. The presence of GAD1 rs1978340 allele A was associated with higher Glu/GABA ratio in BD, while patients without this allele taking mood stabilizers had a lower Glu/GABA ratio. The lowering of dACC Glu/GABA could be one explanation for the mood stabilizing action of anticonvulsants and antipsychotics in BD type I euthymia. Therefore, this putative role of Glu/GABA ratio and the influence of GAD1 genotype interacting with mood stabilization medication should be confirmed by further studies involving larger samples and other mood states.ClincalTrials.gov registration: NCT01237158.

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BACKGROUND: Treatment of bipolar disorder (BD) usually requires drug combinations. Combinations of lithium plus valproic acid (Li/VPA) and lithium plus carbamazepine (Li/CBZ) are used in clinical practice but were not previously compared in a head-to-head trial. OBJECTIVE: The objective of this trial was to compare the efficacy and tolerability of Li/VPA versus Li/CBZ in treating type 1 BD in any phase of illness in young individuals. METHODS: LICAVAL was a randomized, unicenter, open-label, parallel-group trial that was conducted from January 2009 to December 2012 in a tertiary hospital in São Paulo, Brazil. Participants were between 18 and 35 years old and were followed up for 2 years. Our primary outcome was the number of participants achieving/maintaining response and remission during the acute and maintenance phases of BD treatment, respectively. Other outcomes assessed were symptom severity and adverse events throughout the study. In the analysis of the primary outcome, we compared groups by using a two-way repeated measures analysis of variance and estimated effect sizes by using Cohen's d. RESULTS: Of our 64 participants, 36 were allocated to Li/VPA and 28 to Li/CBZ. Our sample was composed predominantly of females (66.6%) and the average age was 27.8 years. A total of 27 (45.0%) participants had depression, 17 (28.3%) had mania/hypomania, and 16 (26.7%) had a mixed state. We found no between-group differences in CGI-BP (Clinical Global Impression Scale modified for use in bipolar disorder) scores (P = 0.326) or in any other outcome. Side effects differed significantly between groups only in the first week of treatment (P = 0.021), and there were more side effects in the Li/VPA group. Also, the Li/VPA group gained weight (+2.1 kg) whereas the Li/CBZ group presented slight weight loss (-0.2 kg). CONCLUSION: Our study suggests that Li/VPA and Li/CBZ have similar efficacy and tolerability in BD but that Li/CBZ might have metabolic advantages in the long term. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00976794 . Registered on September 9, 2009.

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Telomeres are DNA-protein complexes that cap linear DNA strands, protecting DNA from damage. Recently, shorten telomeres length has been reported in bipolar disorder (BD) and depression. The enzyme telomerase regulates telomeres׳ length, which has been associated with cellular viability; however it is not clear how telomerase may be involved in the pathophysiology and therapeutics of BD. In the present study, leukocyte telomerase activity was assessed in 28 medication-free BD depressed individuals (DSM-IV-TR criteria) at baseline and after 6 weeks of lithium therapy (n=21) also matching with 23 healthy controls. There was no difference between telomerase activity in subjects with BD depression (before or after lithium) and controls. Improvement of depressive symptoms was negatively associated with telomerase activity after 6 weeks of lithium therapy. This is the first study describing telomerase activity in BD research. Overall, telomerase activity seems not directly involved in the pathophysiology of short-term BD. Lithium׳s antidepressant effects may involve regulation at telomerase activity. Further studies with larger samples and long-term illness are also warranted.

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Background: Bipolar disorder (BD) patients have been reported to be associated higher creativity abilities, and recent data tend to support the hypothesis that dopaminergic system that could be associated with creativity. Catechol-O-methyltransferase (COMT) is one of the major enzymes involved in the metabolic degradation of dopamine. The COMT gene polymorphism (rs4680 or Val158Met) Met allele is reported to cause decreased activity of this enzyme in prefrontal cortex and improve performance in several cognitive domains. Objective: The objective of this study was to evaluate the influence of Val158Met on creativity in BD type I and healthy controls. Methods: Ninety-seven healthy volunteers and 120 BD type I were genotyped for COMT rs4680 and tested for creativity (Barrow Welsh Art Scale – BWAS) and intelligence Wechsler Abbreviated Scale of Intelligence (WASI). Results: COMT Met allele positively influenced creativity scores in healthy controls but not in BD subjects during mood episodes and euthymia. The presence of allele Met did not influence IQ scores. No influence of IQ total score on creativity was observed. Limitations control group presented higher IQ scores and euthymic group was under medication use. Discussion: Our research suggests positive effect of COMT rs4680 (allele Met) on creativity scores in healthy controls. One possible interpretation is that creativity is more likely to be associated with lesser degrees of bipolarity. The fact that the same results were not observed in BD may be associated to dysfunctions in the dopaminergic system that characterizes this disorder. Further studies with larger samples and other types of BD should explore the role of the dopaminergic system in creativity...

Contexto: O transtorno bipolar (TB) geralmente é associado a pessoas com maiores habilidades criativas, e dados recentes apontam que o sistema dopaminérgico pode estar relacionado à criatividade. A enzima catecol-O-metiltransferase (COMT) é um dos principais agentes envolvidos na degradação metabólica da dopamina. O gene da COMT apresenta um polimorfismo (rs4680 ou Val158Met) no qual o alelo Met se associa a uma diminuição da atividade enzimática da COMT, levando a um melhor desempenho em testes cognitivos. Objetivo O objetivo deste estudo foi avaliar a influência do polimorfismo funcional Val158Met na criatividade de pacientes com TB e em controles. Métodos Noventa e sete voluntários saudáveis e 120 pacientes com TB tipo I foram genotipados para COMT rs4680 e testados para criatividade (Barrow Welsh Art Scale – BWAS) e inteligência (Wechsler Abbreviated Scale of Intelligence – WASI). Resultados: O alelo Met da COMT associou-se a maiores pontuações na escala de criatividade na amostra de controles saudáveis, mas o mesmo não foi observado em pacientes com TB. A presença do alelo Met não influenciou a pontuação de QI em nenhum dos grupos. O grupo controle apresentava QI médio maior que o grupo TB; o grupo TB estava em uso de múltiplas medicações no momento das avaliações. Conclusão: Nossos resultados sugerem influência positiva do alelo Met do COMT rs4680 na criatividade de controles saudáveis. Isso sugere que a criatividade seja uma função possivelmente associada a menores graus de bipolaridade do que nos pacientes com TB tipo I. O fato de não termos observado influência do alelo Met nos resultados dos pacientes com TB pode ser justificado pelo fato de que justamente alterações nesse sistema sejam uma das características básicas do TB. É necessário maior número de estudos commaiores tamanhos amostrais para explorar mais detalhadamente o papel do sistema dopaminérgico na criatividade...

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Cognitive performance in healthy individuals is associated with gender differences in specific tests; a female advantage has been demonstrated in language tests, whereas a male advantage has been demonstrated in spatial relation examinations. The prefrontal cortex (PFC) mediates important cognitive domains and is influenced by dopamine (DA) activity. The single nucleotide polymorphism (SNP) rs4680 in the catechol­O­methyltransferase (COMT) gene results in an amino acid substitution from valine (Val) to methionine (Met). The Met allele has been demonstrated to decrease COMT enzyme activity and improve PFC cognitive function. COMT regulates DA activity in the PFC and exhibits gender effects. The aim of the present study was to investigate the gender­specific effects of the COMT genotype on cognition in healthy young adults. Seventy­six healthy subjects were genotyped for COMT rs4680 and submitted to an extensive range of neuropsychological tests assessing aspects of PFC function. The COMT Met allele influenced the performance of executive function. The results revealed gender effects of the COMT rs4680 Met allele on verbal fluency, with positive effects in males and negative effects in females. This suggested that DA activity affects cognitive function in different ways, according to gender.

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INTRODUCTION: Impairments in facial emotion recognition (FER) have been reported in bipolar disorder (BD) subjects during all mood states. This study aims to investigate the impact of limbic system morphology on FER scores in BD subjects and healthy controls. MATERIAL AND METHODS: Thirty-nine euthymic BD I (type I) subjects and 40 healthy controls were subjected to a battery of FER tests and examined with 3D structural imaging of the amygdala and hippocampus. RESULTS: The volume of these structures demonstrated a differential pattern of influence on FER scores in BD subjects and controls. In our control sample, larger left and right amygdala demonstrated to be associated to less recognition of sadness faces. In BD group, there was no impact of amygdala volume on FER but we observed a negative impact of the left hippocampus volume in the recognition of happiness while the right hippocampus volume positively impacted on the scores of happiness. CONCLUSION: Our results indicate that amygdala and hippocampus volumes have distinct effects on FER in BD subjects compared to controls. Knowledge of the neurobiological basis of the illness may help to provide further insights on the role of treatments and psychosocial interventions for BD. Further studies should explore how these effects of amygdala and hippocampus volumes on FER are associated with social networks and social network functioning.