Márcio Gerhardt Soeiro-de-Souza

Neuropsychological testing of cognitive impairment in euthymic bipolar disorder: an individual patient data meta-analysis.

An association between bipolar disorder and cognitive impairment has repeatedly been described, even for euthymic patients. Findings are inconsistent both across primary studies and previous meta‐analyses. This study reanalysed 31 primary data sets as a single large sample (N = 2876) to provide a more definitive view.

Pharmacological approaches in bipolar disorders and the impact on cognition: a critical overview

Dias VV, Balanzá‐Martinez V, Soeiro‐de‐Souza MG, Moreno RA, Figueira ML, Machado‐Vieira R, Vieta E. Pharmacological approaches in bipolar disorders and the impact on cognition: a critical overview.

Translating neurotrophic and cellular plasticity: from pathophysiology to improved therapeutics for bipolar disorder.

Soeiro‐de‐Souza MG, Dias VV, Figueira ML, Forlenza OV, Gattaz WF, Zarate Jr CA, Machado‐Vieira R. Translating neurotrophic and cellular plasticity: from pathophysiology to improved therapeutics for bipolar disorder.

Multiple levels of impaired neural plasticity and cellular resilience in bipolar disorder: Developing treatments using an integrated translational approach

Abstract Objectives. This paper reviews the neurobiology of bipolar disorder (BD), particularly findings associated with impaired cellular resilience and plasticity. Methods. PubMed/Medline articles and book chapters published over the last 20 years were identified using the following keyword combinations: BD, calcium, cytokines, endoplasmic reticulum (ER), genetics, glucocorticoids, glutamate, imaging, ketamine, lithium, mania, mitochondria, neuroplasticity, neuroprotection, neurotrophic, oxidative stress, plasticity, resilience, and valproate. Results. BD is associated with impaired cellular resilience and synaptic dysfunction at multiple levels, associated with impaired cellular resilience and plasticity. These findings were partially prevented or even reversed with the use of mood stabilizers, but longitudinal studies associated with clinical outcome remain scarce. Conclusions. Evidence consistently suggests that BD involves impaired neural plasticity and cellular resilience at multiple levels. This includes the genetic and intra- and intercellular signalling levels, their impact on brain structure and function, as well as the final translation into behaviour/cognitive changes. Future studies are expected to adopt integrated translational approaches using a variety of methods (e.g., microarray approaches, neuroimaging, genetics, electrophysiology, and the new generation of –omics techniques). These studies will likely focus on more precise diagnoses and a personalized medicine paradigm in order to develop better treatments for those who need them most.

Number of manic episodes is associated with elevated DNA oxidation in bipolar I disorder.

Bipolar disorder (BD) is a major public health problem characterized by progressive functional impairment. A number of clinical variables have been associated with progression of the disease, most notably number of affective episodes and presence of psychotic symptoms, both of which correlate with greater cognitive impairment, lower response rates for lithium, and possibly lower levels of neurotrophic factors. Oxidative damage to cytosine and guanosine (8-OHdG) has been described as a modulator of DNA methylation, but the extent of DNA oxidative damage involvement in BD remains unclear. The aim of this study was to evaluate the extent of DNA oxidative damage to 8-OHdG and 5-methylcytosine (5-HMec), as well as global methylation (5-Mec), in BD patients and healthy controls. Potential association with clinical variables was also investigated. DNA levels of 8-OHdG, 5-HMec and 5-Mec were measured in 50 BD type I patients and 50 healthy controls. DNA 8-OHdG levels were higher in BD patients compared to healthy controls and found to be positively influenced by number of previous manic episodes. BD subjects had lower levels of 5-HMec compared to controls, whereas this measure was not influenced by the clinical features of BD. Number of manic episodes was correlated with higher levels of 8-OHdG, but not of 5-Mec or 5-HMec. Lower demethylation activity (5-HMec) but no difference in global 5-Mec levels was observed in BD. This finding suggests that oxidative damage to 8-OHdG might be a potential marker of disease progression, although further prospective cross-sectional studies to confirm neuroprogression in BD are warranted.

Bcl-2 rs956572 Polymorphism is Associated with Increased Anterior Cingulate Cortical Glutamate in Euthymic Bipolar I Disorder

B-cell lymphoma 2 (Bcl-2) is an important regulator of cellular plasticity and resilience. In bipolar disorder (BD), studies have shown a key role for a Bcl-2 gene single-nucleotide polymorphism (SNP) rs956572 in the regulation of intracellular calcium (Ca2+) dynamics, Bcl-2 expression/levels, and vulnerability to cellular apoptosis. At the same time, Bcl-2 decreases glutamate (Glu) toxicity in neural cells. Abnormalities in Glu function have been implicated in BD. In magnetic resonance spectroscopy (MRS) studies, anterior cingulated cortex (ACC) Glu levels have been reported to be increased in bipolar depression and mania, but no study specifically evaluated ACC Glu levels in BD-euthymia. Here, we compared ACC Glu levels in BD-euthymia compared with healthy subjects using 1H-MRS and also evaluated the selective role of the rs956572 Bcl-2 SNP in modulating ACC Glu and Glx (sum of Glu and glutamine) in euthymic-BD. Forty euthymic subjects with BD type I and forty healthy controls aged 18–40 were evaluated. All participants were genotyped for Bcl-2 rs956572 and underwent a 3-Tesla brain magnetic resonance imaging examination including the acquisition of an in vivo PRESS single voxel (2 cm3) 1H-MRS sequence to obtain metabolite levels from the ACC. Euthymic-BD subjects had higher Glu/Cre (creatine) and Glx/Cre compared with healthy controls. The Bcl-2 SNP AA genotype was associated with elevated ACC Glu/Cre and Glx/Cre ratio in the BD group but not in controls. The present study reports for the first time an increase in ACC Glu/Cre and Glx/Cre ratios in BD-euthymia. Also, Bcl-2 AA genotype, previously associated with lower Bcl-2 expression and increase intracellular Ca2+, showed to be associated with increased ACC Glu and Glx levels in euthymic-BD subjects. The present findings reinforce a key role for glutamatergic system dysfunction in the pathophysiology of BD, potentially involving modulatory effects by Bcl-2 in the ACC.

Association of the COMT Met158 allele with trait impulsivity in healthy young adults

Dopamine (DA) is considered to be an important neurotransmitter in the control of impulsive behavior, however, its underlying mechanisms have not been fully elucidated. Catechol-O-methyltransferase (COMT) is a key enzyme in the catabolism of DA within the prefrontal cortex (PFC) and has been suggested to play a role in the mediation of impulsive behavior. The COMT single nucleotide polymorphism (SNP) rs4680 (Val158Met) Met allele has been shown to decrease COMT enzyme activity and is associated with improved PFC cognitive function (intelligence and executive functions). Studies have associated the rs4680 genotype with impulsivity as a symptom in attention deficit hyperactivity disorder and substance abuse. However, only a few studies have assessed the effects of rs4680 on impulsiveness in healthy subjects, the results of which remain controversial. The Barratt Impulsiveness Scale (BIS-11) was applied to 82 healthy volunteers (including 42 females) who were genotyped for COMT rs4680. Subjects carrying the Met/Met genotype scored higher for the BIS-11 second-order factor Non-planning than carriers of the Val/Val genotype. No interaction between gender genotype was detected. Age, gender and education had no effect on the results. The COMT rs4680 Met/Met genotype was associated with higher impulsivity on the BIS-11 second-order factor Non-planning. These results suggest that COMT enzyme activity may be important in the regulation of impulsiveness among young adults. Further studies involving larger samples should be conducted to confirm the results of the present study.

The impact of a history of psychotic symptoms on cognitive function in euthymic bipolar patients: a comparison with schizophrenic patients and healthy controls

BACKGROUND About two-thirds of patients with bipolar disorder (BD) have a lifetime history of at least one psychotic symptom. OBJECTIVE To compare the neurocognitive performance of four groups: BD patients with and without a history of psychotic symptoms (BD HPS+ and BD HPS-, respectively); patients with schizophrenia (SZ); and healthy control (HC) subjects. METHOD In this cross-sectional study, 35 stabilized patients with SZ, 79 euthymic (44 HPS+ and 35 HPS-) patients with BD, and 50 HC were administered a comprehensive battery of neuropsychological tests. RESULTS There was worse neurocognitive functioning in both BD and SZ patients compared to HC. Overall, data from both groups of BD patients did not differ on sociodemographic, clinical, or neurocognitive variables. However, BD HPS+ patients had significantly more negative symptoms, as measured by the Positive and Negative Syndrome Scale (PANSS), and showed a trend toward worse performance on executive functions compared to BD HPS- patients. Moreover, both BD groups had better performance on all neurocognitive tests compared to SZ group. CONCLUSIONS Neurocognitive dysfunction may be more marked in SZ than in BD, yet qualitatively similar. A history of past psychotic symptoms in BD was not associated with more severe cognitive impairment during euthymia. Therefore, BD with psychotic symptoms does not appear to be a distinct neurocognitive phenotype.

Major depressive disorder in breast cancer: A critical systematic review of pharmacological and psychotherapeutic clinical trials

BACKGROUND While women with breast cancer often face varying levels of psychological distress, there is a subgroup whose symptomatology reaches a threshold for diagnosis of major depressive disorder (MDD). Major depressive disorder is known to influence patient outcomes, such as health-related quality of life and treatment adherence. There are no systematic reviews that evaluate pharmacological and psychotherapeutic treatment trials for MDD among individuals with breast cancer. METHODS Two authors independently searched MEDLINE, EMBASE, Cochrane and Clinical Trials.gov databases through February 20, 2013 without language restrictions. Core journals, reference lists and citation tracking were also searched. Articles on breast cancer patients were included if they (1) included participants with a diagnosis of MDD; (2) investigated pharmacological or psychotherapeutic treatments for MDD compared to placebo or usual care in a randomized controlled trial (RCT). RESULTS Two RCTs on antidepressant treatment met inclusion criteria. However, no RCTs investigating the effects of psychological treatments for MDD in breast cancer were identified. Notwithstanding the paucity of data investigating the effects of psychological treatments for MDD in breast cancer, numerous psychotherapeutic strategies targeting depressive symptoms were identified. Mianserin had significant antidepressant effects when compared to placebo in a 6-week, parallel-group, RCT of Stage I-II breast cancer in women with MDD. Desipramine and paroxetine were reported to be no more efficacious than placebo in a 6-week, RCT of Stage I-IV breast cancer in women with MDD. CONCLUSIONS The evidence reviewed herein underscores the paucity of data available to guide clinicians in treatment decisions for MDD in individuals with breast cancer. Therefore, the treatment of MDD in breast cancer is primarily based on clinical experience. Some antidepressants (for example, paroxetine) should be avoided in women concurrently taking tamoxifen due to relevant interactions involving the cytochrome CYP2D6.

The CACNA1C risk allele selectively impacts on executive function in bipolar type I disorder

Calcium channels are important for converting electrical activity into biochemical events. A single nucleotide polymorphism (SNP) (rs1006737) in the CACNA1C gene has been strongly associated with increased risk for Bipolar disorder (BD) in genome‐wide association studies. Recently, this same SNP has been reported to influence executive function in schizophrenia and controls, but it remains unclear whether this SNP affects behaviour, especially cognition in subjects with BD.