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Many neuropsychiatric disorders are associated with both dopaminergic (DAergic) and developmental hypotheses. Since DAergic receptors are expressed in the developing brain, it is possible that alterations in dopamine (DA) signaling may impair brain development and consequent behavior. In our previous study, using a zebrafish model, we showed that an increase of DA during the 3 to 5 days postfertilization (dpf) developmental window (an important window for GABAergic neuronal differentiation) affects the motor behavior of 5 dpf larvae. In this study, we set out to determine whether these behavioral alterations were sustained in larvae at older stages (7 and 14 dpf). To test this hypothesis, we chronically treated zebrafish larvae from 3 to 5 dpf with DA. After washing the drug, we recorded and analyzed the first 5 and 30 min of the motor behavior of 5, 7, and 14 dpf subjects. We analyzed mobile episodes, distance traveled, time mobile, distance traveled per mobile episode, time in movement per mobile episode, and distance traveled per time mobile. We showed, once again, that an increase of DA during the 3 to 5 dpf developmental window reduces the number of movement episodes initiated by 5 dpf larvae. We also detected a decrease of other motor behavior parameters in 5 dpf DA-treated larvae. We observed that these alterations are sustained in the 7 dpf larvae. However, we did not see these general locomotor alterations in the 14 dpf larvae. Moreover, we detected a decrease of distance traveled and an increase of time of locomotion per episode in the first 5 min of behavioral analyses in 14 dpf DA-treated larvae. To test if the alterations in the first 5 min were due to anxiety-like behavior, we used a light/dark preference paradigm. We recorded 5dpf, 7dpf, and 14dpf larvae for 5 min and analyzed time of freezing, preference for light or dark, number of entries to the dark, percentage of time in the light. We observed that 5dpf larvae treated with DA showed more freezing, less passages to the dark, and more time spent in the light as compared to their control counterparts. But 7dpf and 14dpf larvae did not show these alterations. Taken overall, therefore, our results suggest that DA does play a role in the development of zebrafish motor behavior, and, furthermore, that some behaviors are more sensitive than others to the effects of DAergic imbalances during development.

Telomere length is considered to be a biomarker of biological aging and age-related disease. There are few studies that have evaluated the association between telomere length and diet, and none of them have evaluated the impact of a vegetarian diet on telomere length and its correlation with cardiovascular biomarkers in apparently healthy subjects. Therefore, our objectives were to evaluate leukocyte telomere length (LTL) in vegetarians and omnivorous subjects and its association with classical cardiovascular risk biomarkers. From the total of 745 participants initially recruited, 44 omnivorous and 44 vegetarian men apparently healthy were selected for this study and LTL was measured in 39 omnivorous and 41 vegetarians by Real-Time Quantitative PCR reaction. Although telomere length was not different between omnivorous and vegetarians, we found a strong negative correlation between LTL and IMT (intima-media thickness) in omnivorous, but not in vegetarian group. In addition, omnivorous who were classified with short telomere length had higher carotid IMT compared to vegetarians. Our data suggest that telomere length can be a marker of subclinical atherosclerosis in the omnivorous group.

BACKGROUND: Autoimmune hepatitis (AIH) is a rare chronic inflammatory liver disease associated with a loss of immunological tolerance to self-antigens. Susceptibility to AIH is partially determined by the presence of genes related to human leukocyte antigen (HLA), mainly allelic variants of DRB1. OBJECTIVE: The purpose of this study was to investigate the frequencies of the polymorphisms in HLA-DRB1 gene in children and adolescents with type 1 AIH and type 1 AIH overlap syndrome with autoimmune cholangitis (overlap syndrome, OS) in comparison to healthy sex and age-matched individuals (control group). METHODS: This is a cross-sectional study of 25 pediatric patients diagnosed with type 1 AIH and 18 with OS. Fifty-seven healthy individuals were included as controls. The polymorphisms of the HLA-DRB1 gene were evaluated by PCR and included HLA-DRB1*03, HLA-DRB1*04, HLA-DRB1*07, and HLA-DRB1*13. RESULTS: Our results showed that the presence of the allele HLA-DRB1*13 increased the chance of autoimmune cholangitis (OR=3.96, CI 1.07 to 14.61, P=0.04). The HLA-DRB1*04 and HLA- DRB1*07 have no association with the AIH and autoimmune cholangitis in a young sample. CONCLUSION: This work demonstrates an association of the main polymorphisms in the HLA-DRB1 gene to AIH with or without cholangitis in a Brazilian sample.

Natural disasters have a substantial psychosocial impact. A known biological marker of stress is telomere shortening. In this study, we tested the change in behavior symptoms and telomere length and its shortening in two-time points for about fifteen months, in populations that suffered extreme climate events, comprising flood or drought events. As expected, we observed telomere shortening in children and adolescents after a stressful situation which was directly associated with the worsening of externalizing symptoms and post-traumatic symptoms using a reliable change index. Beyond the psychosocial impact, natural events seem to affect the biology of individuals in development. These findings can help to understand vulnerabilities related to stress impact and to point target populations whose mitigation actions should be addressed in case of a disaster.

Severe Acute Respiratory Syndrome Coronavirus 2 infection causes coronavirus disease 2019. COVID-19 was an unknown infection that reached pandemic proportions in 2020 and has shown to bring long-term negative consequences. Here, we used a case-control design to investigate the performance of relatively young people recovered from COVID 19 in objective neuropsychological tests. We found significant differences between groups for all measures of the ROCFT with a large difference in the copy, a moderate difference in immediate recall, and a large difference in delayed recall. No significant differences were found for the measures from all the other five neuropsychological tests used.About one quarter of COVID 19 patients were below the 10th percentile according to normative data.

Neuromodulation of deep brain structures (deep brain stimulation) is the current surgical procedure for treatment of Parkinson's disease (PD). Less studied is the stimulation of cortical motor areas to treat PD symptoms, although also known to alleviate motor disturbances in PD. We were able to show that optogenetic activation of secondary (M2) motor cortex improves motor functions in dopamine-depleted male mice. The stimulated M2 cortex harbors glutamatergic pyramidal neurons that project to subcortical structures, critically involved in motor control, and makes synaptic contacts with dopaminergic neurons. Strikingly, optogenetic activation of M2 neurons or axons into the dorsomedial striatum increases striatal levels of dopamine and evokes locomotor activity. We found that dopamine neurotransmission sensitizes the locomotor behavior elicited by activation of M2 neurons. Furthermore, combination of intranigral infusion of glutamatergic antagonists and circuit specific optogenetic stimulation revealed that behavioral response depended on the activity of M2 neurons projecting to SNc. Interestingly, repeated M2 stimulation combined withl-DOPA treatment produced an unanticipated improvement in working memory performance, which was absent in control mice underl-DOPA treatment only. Therefore, the M2-basal ganglia circuit is critical for the assembly of the motor and cognitive function, and this study demonstrates a therapeutic mechanism for cortical stimulation in PD that involves recruitment of long-range glutamatergic projection neurons.SIGNIFICANCE STATEMENTSome patients with Parkinson's disease are offered treatment through surgery, which consists of delivering electrical current to regions deep within the brain. This study shows that stimulation of an area located on the brain surface, known as the secondary motor cortex, can also reverse movement disorders in mice. Authors have used a brain stimulation technique called optogenetics, which allowed targeting a specific type of surface neuron that communicates with the deep part of the brain involved in movement control. The study also shows that a combination of this stimulation with drug treatment might be useful to treat memory impairment, a kind of cognitive problem in Parkinson's disease.

Worldwide, floods and drought are the most frequent extreme climate-related disasters with a potential that might affect children and adolescent mental health. This study aimed to describe mental health impact on youth exposed to flood or drought (time 1), to provide a prospective follow up of symptoms (time 2), about 15 months apart, and to compare the child response with control groups based on ranges of socioeconomic status. Posttraumatic stress symptoms (PTSS) and general behavior problems were evaluated. Sociodemographic data from 275 children and adolescents (6 to 18 years old) were described and analyzed and they were gathered in four groups Control group with higher socioeconomic status, Control group with lower socioeconomic status, Flood group, and Drought group. At time point 1, children from all groups did not substantially differ in general behavioral problems, but PTSS scores significantly differentiate the groups. At time point 2, the Flood group presented a pattern of recovery about PTSS. For the Drought group, a persistence and stability pattern of PTSS was verified. Post-disaster longitudinal studies are essential to elucidate how psychological distress progress over time and to understand the relationship between mental health and exposure to trauma.

Epilepsy affects about 1 % of the world population. Mesial temporal lobe epilepsy (mTLE) presents with seizures initiated in hippocampus and is the most frequent form of epilepsy. About 30 % of individuals with mTLE do not respond to conventional medications maintaining seizures and consequently new lesions on a daily basis. Treatment-resistant epilepsy has a huge social and individual burden due to impaired quality of life and increased mortality rate. There are many reasons for telomere shortening in individuals with mTLE, such as a chronic mitochondrial oxidative stress and increased levels of pro-inflammatory mediators. In the past 10 years, there was a boom of studies establishing association between telomere length and chronic/complex disorders. Telomeres are essential for the maintenance of genomic integrity. Telomere length has been assumed as a biological marker for stress and cellular ageing. Here we hypothesized that individuals affected with treatment-resistant mTLE would course with a shorter telomere than controls. So, we measured leucocytes telomere length in a sample of 89 individuals, 48 treatment-resistant mTLE compared to 41 healthy controls. As expected, we observed a significant shorter telomere in the peripheral cell leukocytes of treatment-resitant mTLE group. Telomere length was not associated with sex, side of hippocampal sclerosis, family history, etiology of seizures, duration of disease or the Engel score. Our results points towards the need of further investigation to shed light on the relation of telomeres shortening and the outcomes and impacts of epilepsy.

Background Epilepsy is a disorder characterized by recurrent seizures that affects 1% of the population. However, the neurochemical alterations observed in epilepsy are not fully understood. There are different animal models of epilepsy, such as genetic or drug induced. In the present study, we utilize Wistar Audiogenic Rats (WAR), a murine strain that develops seizures in response to high intensity audio stimulation, in order to investigate abnormalities in glutamatergic and GABAergic systems. Methods Synaptosomes and glial plasmalemmal vesicles were prepared from hippocampus and cortex, respectively. Glutamate and GABA release and uptake were assayed by monitoring the fluorescence and using L-[3H]-radiolabeled compounds. Glutamate and calcium concentration in the synaptosomes were also measured. The expression of neuronal calcium sensor 1 (NCS-1) was determined by western blot. Results Glutamate and GABA release evoked by KCl was decreased in WAR compared to control Wistar rats. Calcium independent release was not considerably different in both groups. The total amount of glutamate of synaptosomes, as well as glutamate uptake by synaptosomes and GPV were also decreased in WAR in comparison with the controls. In addition, [Ca2+]i of hippocampal synaptosomes, as well as NCS-1 expression in the hippocampus, were increased in WAR in comparison with controls. Conclusion In conclusion, our results suggest that WAR have important alterations in the glutamatergic and GABAergic pathways, as well as an increased expression of NCS-1 in the hippocampus and inferior colliculus. These alterations may be linked to the spreading of hyperexcitability and recruitment of various brain regions.

The International League Against Epilepsy (ILAE) classification system for hippocampal sclerosis (HS) is based on location and extent of hippocampal neuron loss. Specific subgroups have a better surgical prognosis. Automated hippocampal subfields segmentation and volume measure could be obtained from high field MRI and used to pre-operatively classify the patients in ILAE subgroups to define best candidates for surgery. This prospective study included 86 MTLE patients, candidates to surgical treatment and ten healthy volunteers. Volumetric analysis of the hippocampal sublayers was performed through the Freesurfer software, using 3 Teslas volumetric T1 weighted MRI. We correlated the hippocampal subfields measures with the seizure control after one year from surgery. Volume loss in Cornu Amonis (CA) 1 and 4 were related to better surgical outcome after one year. Atrophy in CA 2 and CA 3 did not improve the prognosis. These results are in agreement with the ILAE classification of hippocampal subfields sclerosis.

Aim: The aim of this study is to evaluate the presence of a particular immunological profile in individuals long-term infected with HTLV-1, followed presenting different clinical courses. Materials & methods: Forty-eight individuals were evaluated for 19 cytokines analyzed in cerebrospinal fluid and plasma of patients with HTLV-1 presenting with and without neurological symptoms. Results: Proinflammatory cytokines and the chemokine ligand 11 (ITAC/CXCL11) were increased in individuals with HTLV-1 coursing with neurological symptoms. Conclusion: Different cytokines’ expression profile in the presence of neurological symptoms may help to understand and characterize the progression for severe clinical presentations.

Objective To compare the proinflammatory and anti-inflammatory cytokine expression profile of CD4 + and CD8 + T lymphocytes between drug resistant mesial Temporal Lobe Epilepsy (mTLE) patients and healthy subjects. Methods mTLE patients were enrolled at the Neurology Center of Santa Casa de Misericordia de Belo Horizonte (SCM-BH) and healthy volunteers were selected at Universidade Federal de Minas Gerais. Individuals from both groups accepted to participate in this study and signed an informed consent. Peripheral venous blood samples were collected using sodium heparin vacuum tubes on the day before the surgery and in the interictal period, isolated from whole blood using Ficoll/Hypaque followed by flow cytometry analysis. Data analysis was performed using FlowJo. Results Compared to healthy individuals, mTLE patients showed reduced frequency of CD8 + T lymphocytes expressing IFN-γ, TNF-α, IL-17 and IL-4. Moreover, mTLE patients presented increased frequency of CD4 + T lymphocytes expressing IL-6 when compared to healthy volunteers. Discussion Epilepsy is the third most common chronic brain disorder. Mesial temporal lobe epilepsy (mTLE) is a major and severe form of epilepsy and 30% of the mTLE patients do not respond to conventional medications. Our data suggest that mTLE patients have distinct immunological profiles that are related to disease pathophysiology.

Brain preconditioning is a protective mechanism, which can be activated by sub-lethal stimulation of the NMDA receptors (NMDAR) and be used to achieve neuroprotection against stroke and neurodegenerative diseases models. Inhibitors of glycine transporters type 1 modulate glutamatergic neurotransmission through NMDAR, suggesting an alternative therapeutic strategy of brain preconditioning. The aim of this work was to evaluate the effects of brain preconditioning induced by NFPS, a GlyT1 inhibitor, against NMDA-induced excitotoxicity in mice hippocampus, as well as to study its neurochemical mechanisms. C57BL/6 mice (male, 10-weeks-old) were preconditioned by intraperitoneal injection of NFPS at doses of 1.25, 2.5 or 5.0 mg/kg, 24 h before intrahippocampal injection of NMDA. Neuronal death was evaluated by fluoro jade C staining and neurochemical parameters were evaluated by gas chromatography-mass spectrometry, scintillation spectrometry and western blot. We observed that NFPS preconditioning reduced neuronal death in CA1 region of hippocampus submitted to NMDA-induced excitotoxicity. The amino acids (glycine and glutamate) uptake and content were increased in hippocampus of animals treated with NFPS 5.0 mg/kg, which were associated to an increased expression of type-2 glycine transporter (GlyT2) and glutamate transporters (EAAT1, EAAT2 and EAAT3). The expression of GlyT1 was reduced in animals treated with NFPS. Interestingly, the preconditioning reduced expression of GluN2B subunits of NMDAR, whereas did not change the expression of GluN1 or GluN2A in all tested doses. Our study suggests that NFPS preconditioning induces resistance against excitotoxicity, which is associated with neurochemical changes and reduction of GluN2B-containing NMDAR expression.

Aim The angiotensin type 2 (AT2) receptor takes part in the process of ureteric bud during kidney development. Therefore, the gene encoding AT2 receptor, the AGTR2 gene located in the X chromosome, is a potential candidate for genetic association with Congenital Anomalies of the Kidney and Urinary Tract (CAKUT). This study aimed to investigate whether AGTR2 gene polymorphisms are associated with CAKUT in general or even with common phenotypes of CAKUT in a Brazilian sample of paediatric patients. Methods We analyzed 290 paediatric patients with CAKUT and 262 healthy controls from the same geographic area. TaqMan single-nucleotide polymorphism (SNP) genotyping assays for AGTR2 gene at rs1403543, rs3736556, rs35474657, rs5193 and rs5194 were performed. The sample was in Hardy–Weinberg Equilibrium for all five SNPs. Results The presence of CAKUT in general was not significantly associated with the SNPs included in this study. However, when patients were segregated according to major phenotypes, the diagnosis of Ureteropelvic Junction Obstruction (UPJO) was significantly associated with AGTR2 gene polymorphisms at rs3736556 and at rs5194. On the other hand, the diagnoses of vesicoureteral reflux and of multicystic dysplastic kidney were not associated with AGTR2 gene polymorphisms. Conclusion Our results support that the AGTR2 gene may contribute to the pathogenesis of UPJO and the genetic origin of CAKUT could vary according to phenotype expression.

Sepsis is defined as the host's reaction to infection and it is characterized by a systemic inflammatory response with important clinical implications. Central nervous system dysfunction secondary to sepsis is associated with local generation of pro- and anti-inflammatory cytokines, impaired cerebral microcirculation, disturbance of neurotransmitters, apoptosis, and cognitive impairment. It is known that during the process of learning and memory formation several pathways are involved such as dopaminergic and cholinergic systems. Thus, the objective of this study is to evaluate the neuronal calcium sensor (NCS-1) and dopamine-cAMP regulated phosphoprotein of 32,000 kDa (DARPP-32) expression as well as brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) levels in prefrontal cortex and hippocampus of rats 12, 24, and 48 h after sepsis induction. To this aim, we used sham-operated Wistar rats or submitted to the cecal ligation and perforation procedure. After 12 and 24 h, there was an increase of NGF levels in hippocampus; and up to 48 h, a decrease of NCS-1 expression in prefrontal cortex, a decrease of BDNF levels in hippocampus and an increase of NGF levels in hippocampus. In conclusion, we believe that the low expression of NCS-1 in prefrontal cortex and low levels of BDNF in hippocampus may be associated with the pathophysiology of cognitive impairment during sepsis and a putative role of the dopaminergic system.

Brain ischemic tolerance is an endogenous protective mechanism activated by a preconditioning stimulus that is closely related to N -methyl- d -aspartate receptor (NMDAR). Glycine transporter type 1 (GlyT-1) inhibitors potentiate NMDAR and suggest an alternative strategy for brain preconditioning. The aim of this work was to evaluate the effects of brain preconditioning induced by sarcosine, a GlyT-1 inhibitor, against global cerebral ischemia and its relation to NMDAR. Sarcosine was administered over 7 days (300 or 500 mg/kg/day, ip) before the induction of a global cerebral ischemia model in Wistar rats (male, 8-week-old). It was observed that sarcosine preconditioning reduced cell death in rat hippocampi submitted to cerebral ischemia. Hippocampal levels of glycine were decreased in sarcosine-treated animals, which was associated with a reduction of [ 3 H] glycine uptake and a decrease in glycine transporter expression (GlyT-1 and GlyT-2). The expression of glycine receptors and the NR1 and NR2A subunits of NMDAR were not affected by sarcosine preconditioning. However, sarcosine preconditioning reduced the expression of the NR2B subunits of NMDAR. In conclusion, these data demonstrate that sarcosine preconditioning induces ischemic tolerance against global cerebral ischemia and this neuroprotective state is associated with changes in glycine transport and reduction of NR2B-containing NMDAR expression.

The Human T-cell leukemia virus type-I (HTLV-1) is the causal agent of HTLV-associated myelopathy/Tropical Spastic Paraparesis (HAM/TSP). HAM/TSP is the result of demyelination and cell death in the spinal cord and disruption of the blood-brain barrier (BBB), mediated by a virus-induced inflammatory response. In this study, we applied Positron Emission Tomography with 18F-fluordeoxyglucose (18F-FDG PET) to evaluate brain metabolism in a group of 47 patients infected with HTLV-1, and 18 healthy controls. Patients were divided into three groups according to their neurological symptoms. A machine learning (ML) based Gaussian Processes classification algorithm (GPC) was applied to classify between patient groups and controls and also to organize the three patient groups, based on gray and white matter brain metabolism. We found that GPC was able to differentiate the HAM/TSP group from controls with 85% accuracy (p = 0.003) and the asymptomatic seropositive patients from controls with 85.7% accuracy (p = 0.001). The weight map suggests diffuse cortical hypometabolism in both patient groups when compared to controls. We also found that the GPC could separate the asymptomatic HTLV-1 patients from the HAM/TSP patients, but with a lower accuracy (72.7%, p = 0.026). The weight map suggests a diffuse pattern of lower metabolism in the asymptomatic group when compared to the HAM/TSP group. These results are compatible with distinctive patterns of glucose uptake into the brain of HTLV-1 patients, including those without neurological symptoms, which differentiate them from controls. Furthermore, our results might unveil surprising aspects of the pathophysiology of HAM/TSP and related diseases, as well as new therapeutic strategies.

Objective Alzheimer's disease (AD) has a multifactorial etiology involving an interaction of genetic and environmental factors. The Apolipoprotein E e4 (ApoE e4) is the single most important genetic risk factor for sporadic AD. Our aim was to study the association between sociodemographic, clinical data and gene polymorphisms in patients with sporadic AD in a heterogeneous genomic Brazilian population with low educational levels. Methods We selected 169 sporadic AD patients and 97 controls older than 65 years and compared co-variables between them: age, years of education, vascular risk factors, genomic ancestry, and functional polymorphisms of ApoE, BDNF, COMT, and 5-HTTLPR. We also determined the genomic ancestry of all individuals. Results The average years of education was significantly smaller in the patient's group (p = 0.003), and they had a history of depression when compared with controls (p

Psychiatric disorders are among the most common human illnesses; still, the molecular and cellular mechanisms underlying their complex pathophysiology remain to be fully elucidated. Over the past 10 years, our group has been investigating the molecular abnormalities in major signaling pathways involved in psychiatric disorders. Recent evidences obtained by the Instituto Nacional de Ciência e Tecnologia de Medicina Molecular (National Institute of Science and Technology - Molecular Medicine, INCT-MM) and others using behavioral analysis of animal models provided valuable insights into the underlying molecular alterations responsible for many complex neuropsychiatric disorders, suggesting that "defects" in critical intracellular signaling pathways have an important role in regulating neurodevelopment, as well as in pathophysiology and treatment efficacy. Resources from the INCT have allowed us to start doing research in the field of molecular imaging. Molecular imaging is a research discipline that visualizes, characterizes, and quantifies the biologic processes taking place at cellular and molecular levels in humans and other living systems through the results of image within the reality of the physiological environment. In order to recognize targets, molecular imaging applies specific instruments (e.g., PET) that enable visualization and quantification in space and in real-time of signals from molecular imaging agents. The objective of molecular medicine is to individualize treatment and improve patient care. Thus, molecular imaging is an additional tool to achieve our ultimate goal. Os transtornos psiquiátricos estão entre as doenças humanas mais comuns. Os mecanismos celulares e moleculares subjacentes à sua complexa fisiopatologia ainda não estão totalmente esclarecidos. Nosso grupo está envolvido na investigação de anormalidades moleculares nas principais vias de sinalização das doenças psiquiátricas nos últimos 10 anos. Evidências recentemente obtidas pelo Instituto Nacional de Ciência e Tecnologia de Medicina Molecular (INCT-MM), utilizando análise comportamental de modelos animais, forneceram informações valiosas sobre as alterações moleculares subjacentes responsáveis por muitos distúrbios neuropsiquiátricos complexos, sugerindo que os "defeitos" nas vias de sinalização intracelular têm um papel importante na regulação do neurodesenvolvimento, bem como na fisiopatologia e eficácia do tratamento. Recursos do INCT nos permitiram iniciar pesquisas na área de imagem molecular. A imagem molecular é uma disciplina de investigação que visualiza, caracteriza e quantifica processos biológicos que ocorrem em níveis celular e molecular em seres humanos, e em outros sistemas vivos, através dos resultados de imagem dentro da realidade do ambiente fisiológico. A fim de reconhecer alvos, a imagem molecular aplica instrumentos específicos (PET, por exemplo) que permitem a visualização e quantificação em espaço e tempo real dos sinais dos agentes de imagem molecular, fornecendo medições de processos a nível molecular e celular. O objetivo da medicina molecular é individualizar o tratamento e melhorar a assistência ao paciente. Desse modo, a imagem molecular consiste em mais uma ferramenta para atingirmos nosso objetivo final.

It is well known that dopamine imbalances are associated with many psychiatric disorders and that the dopaminergic receptor D₂ is the main target of antipsychotics. Recently it was shown that levels of two proteins implicated in dopaminergic signaling, Neuronal calcium sensor-1 (NCS-1) and DARPP-32, are altered in the prefrontal cortex (PFC) of both schizophrenic and bipolar disorder patients. NCS-1, which inhibits D₂ internalization, is upregulated in the PFC of both patients. DARPP-32, which is a downstream effector of dopamine signaling, integrates the pathways of several neurotransmitters and is downregulated in the PFC of both patients. Here, we used PC12 cells stably overexpressing NCS-1 (PC12-NCS-1 cells) to address the function of this protein in DARPP-32 signaling pathway in vitro. PC12-NCS-1 cells displayed downregulation of the cAMP/PKA pathway, with decreased levels of cAMP and phosphorylation of CREB at Ser133. We also observed decreased levels of total and phosphorylated DARPP-32 at Thr34. However, these cells did not show alterations in the levels of D₂ and phosphorylation of DARPP-32 at Thr75. These results indicate that NCS-1 modulates PKA/cAMP signaling pathway. Identification of the cellular mechanisms linking NCS-1 and DARPP-32 may help in the understanding the signaling machinery with potential to be turned into targets for the treatment of schizophrenia and other debilitating psychiatric disorders.

Background HTLV-1 infection is endemic in Brazil. About 1 to 2% of the Brazilian population is estimated to be infected, but most infected HTLV-1 individuals do not know about their own infection, which favors the continuity of sexual and vertical virus transmission. In addition, HTLV-1 associated central nervous system diseases and their pathophysiologic mechanisms are not fully understood. This study aimed to evaluate the correlation of spinal cord metabolism, viral and inflammatory profiles with features of neurological presentation in HTLV-1 infected individuals. Methodology This is a cross-sectional study of a cohort including 48 HTLV-1 infected individuals clinically classified as asymptomatic-AG (N = 21), symptomatic-SG (N = 11) and HAM/TSP-HG (N = 16) and a nested case-control study with HTLV-1 infected individuals-HIG (N = 48) and HTLV-1 non infected controls-CG (N = 30) that had their spinal cord analysed by Positron Emission Tomography with 18F-Fluordeoxyglucose (18F-FDG PET/CT). HTLV-1 infected individuals had 18F-FDG PET/CT results analyzed with clinical and demographic data, proviral load, cytokines and chemokines in the blood and cerebrospinal fluid (CSF). Principal Findings 18F-FDG PET/CT showed hypometabolism in the thoracic spinal cord in HTLV-1 infected individuals. The method had an accuracy of 94.4% to identify HAM/TSP. A greater involvement of the thoracic spinal cord was observed, although hypometabolism was also observed in the cervical spinal cord segment in HTLV-1 infected individuals. Individuals with HAM/TSP showed a pro-inflammatory profile in comparison to asymptomatic and symptomatic groups, with a higher level of Interferon-inducible T-cell alpha chemoattractant (ITAC/CXCL11), IL-6, IL-12p70 in the plasma; and ITAC, IL-4, IL-5, IL-8 (CXCL8) and TNF-alpha in the CSF. Using regression, thoracic spinal cord SUV (standardized uptake value) and CSF ITAC level were identified as the HAM/TSP predictors in the multivariate model. Conclusions 18F-FDG PET/CT imaging showed spinal cord hypometabolism in most HTLV-1 infected individuals, even in the asymptomatic HTLV-1 group. Thoracic spinal cord hypometabolism and CSF-ITAC levels were identified predictors of HAM/TSP. Significance Our findings suggested that in most HTLV-1 infected individuals there was compromise of central nervous system (CNS) structures despite of the lack of clinical symptoms. To explain the found hypometabolism, the role of microcirculatory and metabolic factors in the pathogenesis of neurological diseases associated with HTLV-1 infection must be further investigated. It is paramount to evaluate the central nervous function and to compare the performance among HTLV-1 infected individuals considered asymptomatic to the uninfected controls.

Abnormal activities of critical antioxidant enzymes and other indices of lipid peroxidation in plasma and red blood cells were detected in patients with schizophrenia. Other results have shown that oxidative stress may be modulated by clozapine. Based on that and some studies already found different clinical relations between reactive oxygen species and negative and positive symptoms, we evaluated association between clinical response and the polymorphism in the human glutathione peroxidase (GPX1) (Pro200Leu, rs1050450) and manganese SOD (MNSOD) (Ala16Val, rs4880) gene in 216 clozapine-treated patients with schizophrenia. No association was found with these two functional polymorphisms and clozapine response and symptom change after 6 months. No correlations were found between positive/negative symptoms score and both polymorphisms. Our results present that GPX1 (Pro200Leu) and MNSOD (Ala16Val) polymorphisms seem do not play a central role in the clozapine response, although studies in larger and independent samples are necessary to confirm our findings. Copyright © 2009 John Wiley & Sons, Ltd.

It has been reported that C825T variant in the gene encoding the G-protein subunit beta3 (GNB3) is associated with antipsychotic-induced weight gain and obesity. We investigated the association of the GNB3 and antipsychotic-induced weight gain as well as body mass index (BMI) using meta-analytical techniques. Our analysis of 402 schizophrenia subjects showed a trend (p=0.072) only under a fixed-model. As it was observed heterogeneity among the studies (p=0.007), we re-analyzed using a random-effects framework and no significance was found (p=0.339). No evidence for bias publication was reported (p=0.868). Our analysis of 18,903 subjects showed a trend (p=0.053) associating CC and lower BMI under a fixed model. Although no significant association was found, the same pattern (CC and lower antipsychotic-induced weight gain) was observed. Our meta-analysis indicates that firmly establishing the role of pharmacogenetics in clinical psychiatry requires much larger sample sizes that have been reported.

Dopamine may alter the phosphorylation state of DARPP-32 that plays a central role in the dopaminergic neurons biology. Studies have shown that DARPP-32/protein phosphatase 1 cascade is a major target for psychostimulants drugs. Methylphenidate is a psychostimulant that acts blocking the dopamine transporter has been used as an effective treatment for Attention Deficit Hyperactivity Disorder. We investigated if methylphenidate could alter DARPP-32 expression in five brain regions (striatum, hippocampus, prefrontal cortex, cortex and cerebellum) in young and adult rats. Our results showed that methylphenidate treatment is able to alter DARPP-32 expression in rat brain. Acute methylphenidate treatment has reduced hippocampal DARPP-32 protein levels in old rats, while chronic methylphenidate treatment has decreased them in old rat hippocampus and young rat cerebellum. It was found an increased cortical expression after chronic methylphenidate administration in old rats. Our results provide the first experimental demonstration that methylphenidate induces changes in total DARPP-32 expression that are posology- and age-related in some rat brain areas, although further studies are needed to shed more light on the mechanisms behind these findings.

Although electroconvulsive therapy (ECT) has been used as a treatment for mental disorder since 1930s, little progress has been made in the mechanisms underlying its therapeutic or adverse effects. The aim of this work was to analyze the expression of DARPP-32 (a protein with a central role in dopaminergic signaling) in striatum, cortex, hippocampus and cerebellum of Wistar rats subjected to acute or chronic electroconvulsive stimulation (ECS). Rats were submitted to a single stimulation (acute) or to a series of eight stimulations, applied one every 48 h (chronic). Animals were killed for collection of tissue samples at time zero, 0.5, 3, 12, 24 and 48 h after stimulation in the acute model and at the same time intervals after the last stimulation in the chronic model. Our results indicated that acute ECS produces smaller changes in the expression of DARPP-32 but, interestingly, chronic ECS increased transient expression of DARPP-32 in several time frames, in striatum and hippocampus, after the last stimulation. Results on the expression of proteins involved in signaling pathways are relevant for neuropsychiatric disorders and treatment, in particular ECT, and can contribute to shed light on the mechanisms related to therapeutic and adverse effects.

Although electroconvulsive therapy (ECT) has been used as a treatment for mental disorder since 1930s, little progress has been made towards understanding the mechanisms underlying its therapeutic and adverse effects. The aim of this work was to analyze the expression of NCS-1 (neuronal calcium sensor 1, a protein that was found to be altered in post-mortem prefrontal cortex of schizophrenic patients) in striatum, cortex, hippocampus and cerebellum of Wistar rats after acute or chronic electroconvulsive stimulation (ECS). Rats were submitted to a single stimulation (acute) or to a series of eight stimulations, applied one every 48 h (chronic). Animals were killed for collection of tissue samples at time zero, 30 min, 3, 12, 24 and 48 h after stimulation in the acute model and at the same time intervals after the last stimulation in the chronic model. Our results indicated that chronic ECS increased the expression of NCS-1 only in cerebellum. Such results on the expression of proteins involved in signaling pathways that are relevant for neuropsychiatric disorders and treatment, in particular ECT, can contribute to shed light on the mechanisms related to therapeutic and adverse effects.

Changes in dopaminergic function can be regulated by receptor-receptor interaction, or interaction with other proteins with dopamine receptors, and/or elements of the downstream signaling cascades. The complexity of dopaminergic signaling is far from being completely elucidated. It could, however, hold the key to the comprehension of the pathophysiology of neurological and psychiatric disorders, as well as to the identification of putative new targets for, and development of, more efficacious and selective drugs. Here, we review some of the current evidence and new ideas that are being proposed as a result, as well as future perspectives that are now being recognized.

Telomere length (TL) is highly heritable, and a shorter telomere at birth may increase the risk of age-related problems. Telomere length (TL) is highly heritable, and a shorter telomere at birth may increase the risk of age-related problems. Additionally, a shorter TL may represent a biomarker of chronic stress and has been associated with psychiatric disorders. However, no study has explored whether there is an association between TL and the symptoms of one of the most common neurodevelopmental disorders in childhood: Attention Deficit/Hyperactive Disorder (ADHD). We evaluated 61 (range, 6-16 years) ADHD children and their parents between 2012 and 2014. Telomere length was measured with a quantitative polymerase chain reaction method with telomere signal normalized to the signal from a single copy gene (36B4) to generate a T/S ratio. Family data was processed through a GEE model to determine the effect of parental TL on children TL. Inattentive and hyperactive-impulsive symptoms were also evaluated in relation to TL. For the first time, we found general heritability to be the major mechanism explaining interindividual telomere length variation in ADHD (father-child: 95%CI=0.35/0.91, p0.05). The ADHD inattentive dimension was not significant associated with TL in this study (p>0.05). TL was shown to be a potential biomarker of the ADHD symptoms burden in families affected by this neurodevelopmental disorder. However, it is crucial that future studies investigating the rate of telomere attrition in relation to psychiatric problems to consider the strong determination of telomere length at birth by inheritance.

NALCN (sodium leak channel, non-selective) is located on chromosome 13q (suggested linkage region for schizophrenia). We analyzed 21 polymorphisms in 464 schizophrenia subjects, 220 controls subjects and 119 small nuclear families. We observed nominal association with rs9518320 and rs9518331, suggesting that NALCN is not related to schizophrenia risk.

Background Telomeres can be considered a marker of biological aging. Studies have suggested that telomere shortening may be associated with aging related diseases and also psychiatric disorders. Objectives Investigate whether bipolar disorder (BD) and its clinical specificities are associated with telomere shortening. Methods Eighty-five BD patients and 95 healthy controls were paired for age, sex and educational level. Volunteers were submitted to a psychiatric interview and clinical evaluation. Patients and controls were compared as a whole sample and within specific telomere range (short and long telomeres). Intrapatients group comparison involved type of BD and comorbidities. A Real Time Quantitative PCR was performed in order to verify leukocytes telomere length. Results Bipolar disorder patients presented shorter telomeres when compared to controls ( p 0.001). However, there was no significant difference in telomere length between different BD subtypes. When two groups of patients (long and short telomeres) were compared, only panic disorder showed an association with telomere categories ( χ 2 =6.91; p= 0.009; OR=4.27). Limitations It was not possible to collect information about time since diagnosis, which limited conclusions regarding BD chronicity and telomere length. Furthermore, medication interference upon telomere length was not controlled. Conclusions Results suggest that BD is associated with reduced telomere length. Also, panic comorbidity may represent an additive risk factor. Understanding aspects that contribute to determination of telomere size in bipolar patients allows us to understand what the impact on telomeres size is, which is a health vulnerability marker.

Background Antipsychotics are essential for the treatment of schizophrenia. However, due to side effects, both continuity of treatment and patients' general health can be jeopardized. Some of these drugs, especially clozapine, have a class of side effects attributed to their antimuscarinic properties, such as dysmotility, a condition in which muscles of the digestive system become impaired. Dysmotility may also alter the speed, strength or coordination of the digestive organs, causing distention, disturbing gastrointestinal transit, leading to symptoms such as bloating, nausea, vomiting, and even malnutrition. In this study, our aim was to develop an in vivo assay capable of identifying and studying the antimuscarinic effects of antipsychotics in a zebrafish model. Methods We performed video recordings of in vivo 5-day postfertilization (dpf) zebrafish larvae gastrointestinal tracts and analyzed the frequency of spontaneous and regular cycles of contractions of the gut. Key Results The assay was first validated with treatment with atropine. We showed that this antimuscarinic drug reduces peristaltic cycles. Subsequently, the larvae were treated with the antipsychotics haloperidol, risperidone, and clozapine. Neither haloperidol nor risperidone reduced gut motility, but clozapine significantly reduced the frequency of cycles of contractions (P

Sensing and regulating intracellular levels of calcium are essential for proper cellular function. In neurons, calcium sensing plays important roles in neuronal plasticity, neurotransmitter release, long-term synapse modification and ion channel activity. Neuronal calcium sensor-1 (NCS-1) is a member of the highly conserved neuronal calcium sensor family. Although NCS-1 has been associated with psychiatric conditions including autism, bipolar disorder and schizophrenia, it is unclear which role NCS-1 plays in behavior. To understand the involvement of NCS-1 in psychiatric conditions, we provided a comprehensive behavioral characterization of NCS-1 knockout (KO) mice. These mice grow and develop normally without apparent abnormalities in comparison to wild type littermates. However, open field showed that NCS-1 deficiency impairs novelty-induced exploratory activity in both KO and heterozygote (HT) mice. Moreover, NCS-1-deficiency also resulted in anxiety- and depressive-like behaviors as demonstrated by elevated plus maze, large open field, forced swim and tail suspension tasks. Furthermore, based on spontaneous object recognition test, non-aversive long-term memory was impaired in NCS-1 KO mice. In contrast, neither social behavior nor a kind of aversive memory was affected under NCS-1 deficiency. These data implicate NCS-1 in exploratory activity, memory and mood-related behaviors, suggesting that NCS-1 gene ablation may result in phenotypic abnormalities associated with neuropsychiatric disorders.

Sepsis is characterized by an intense inflammatory reaction with potential neurotoxic effects in the central nervous system and damage to memory and learning ability. We assessed the effects of acute low dose of MK-801 on the memory impairment, hippocampal BDNF levels and DARPP-32 expression ten days after sepsis. Under anesthesia, male Wistar rats underwent either cecal ligation and perforation (CLP) or sham. Then, the animals received either a single systemic injection of MK-801 (0.025 mg/kg) or saline solution. Ten days after CLP, the animals were submitted to the step-down inhibitory avoidance and object recognition tests. Also, the hippocampal BDNF protein levels and DARPP-32 expression were evaluated. MK-801 prevented cognitive impairment, but did not affect the hippocampal BDNF levels. DARPP-32 expression was significantly different only in the animals submitted to sepsis that received MK-801 treatment. Thus, we demonstrated that a single low dose of MK-801 prevented memory impairment without altering hippocampal DARPP-32 expression and BDNF levels.

Step-down inhibitory avoidance is usually acquired in one single trial, which makes it ideal for studying processes initiated by training, uncontaminated by prior or further trials, rehearsals, or retrievals. Neuronal calcium sensor 1 (NCS-1) is a dopamine receptor interacting protein that has been associated with associative learning and memory. We evaluated whether inhibitory avoidance can alter NCS-1 levels in rat brain. We focused our analysis on the striatum, entorhinal cortex, hippocampus and prefrontal cortex. Protein levels were measured using immunoblotting normalized by actin levels. Our results indicate that NCS-1 levels are not altered after step-down inhibitory avoidance in rat striatum, entorhinal cortex, hippocampus and prefrontal cortex. The link between protein interactions and the varied physiological roles of NCS-1 still remains to be fully established. Furthermore, other experiments are needed to shed more light on the role of NCS-1 and other mechanisms linked to signaling pathways related to inhibitory avoidance task.

Methylphenidate has been used as an effective treatment for attention deficit hyperactivity disorder (ADHD). Methylphenidate (MPH) blocks dopamine and norepinephrine transporters causing an increase in extracellular levels. The use of psychomotor stimulants continues to rise due to both the treatment of ADHD and illicit abuse. Methylphenidate sensitization mechanism has still poor knowledge. Neuronal calcium sensor 1 was identified as a dopaminergic receptor interacting protein. When expressed in mammalian cells, neuronal calcium sensor 1 attenuates dopamine-induced D2 receptor internalization by a mechanism that involves a reduction in D2 receptor phosphorylation. Neuronal calcium sensor 1 appears to play a pivotal role in regulating D2 receptor function, it will be important to determine if there are alterations in neuronal calcium sensor 1 in neuropathologies associated with deregulation in dopaminergic signaling. Then, we investigated if methylphenidate could alter neuronal calcium sensor 1 expression in five brain regions (striatum, hippocampus, prefrontal cortex, cortex and cerebellum) in young and adult rats. These regions were chosen because some are located in brain circuits related with attention deficit hyperactivity disorder. Our results showed changes in neuronal calcium sensor 1 expression in hippocampus, prefrontal cortex and cerebellum mainly in adult rats. The demonstration that methylphenidate induces changes in neuronal calcium sensor 1 levels in rat brain may help to understand sensitization mechanisms as well as methylphenidate therapeutic effects to improve attention deficit hyperactivity disorder symptoms.

Step-down inhibitory avoidance (IA) is usually acquired in one single trial, which makes it ideal for studying processes initiated by training, uncontaminated by prior or further trials, rehearsals, or retrievals. Biochemical events in the hippocampus related to long-term memory (LTM) formation have been extensively studied in rats using a one trial step-down IA task. DARPP-32 (dopamine and cAMP regulated phosphoprotein of Mr 32 kDa) is a cytosolic protein that is selectively enriched in medium spiny neurons in the neostriatum. It has been shown that activation of DARPP-32 and the resultant inhibition of PP-1 activity is critical for the expression of two opposing forms of brain synaptic plasticity, striatal LTD and LTP. Both forms of plasticity are also critically linked to the activation of DA receptors. It has been shown with studies in DARPP-32 KO mice an important role of this protein in mediating the effects of DA on long term changes in neuronal excitability and to our knowledge, no studies have examined the effect of IA task on DARPP-32 expression. In order to demonstrate changes in the protein expression profile we analyzed DARPP-32 levels in the striatum, prefrontal cortex (PFC), hippocampus and entorhinal cortex of Wistar rats after step-down IA learning. Our results showed that IA induced changes on DARPP-32 expression in striatum and hippocampus. DARPP-32 expression changes corroborate with changes in expression and phosphorylation of CREB, NMDA, AMPA after IA that has been reported. These changes suggest that DARPP-32 might play a central role in the IA, as previously described as an integrator of the dopaminergic signal.

Signaling pathways play important roles in the coordination and integration of a myriad cellular functions. Because of widespread interest in the dopaminergic pathways, the protein dopamine and cyclic adenosine 3',5'-monophosphate-regulated phosphoprotein with molecular weight of 32 kDa, known by the acronym DARPP-32, occupies a central role in the biology of dopaminoceptive neurons in the central and peripheral nervous system (PNS). Its involvement has been demonstrated in many neural phenomena, including physiologic and pathologic neuroplasticity to drug effects and cognition. However, DARPP-32 has also been identified in non-neuronal tissues and its level of expression has been associated with the malignant level of some types of cancer, via modulation of cell survival and differentiation. This review considers some of these apparently compartmentalized functions of DARPP-32 and its potential as a therapeutic target.

Chronic ingestion of caffeine causes dependence and sleep disturbance in children and adolescents. In rodents, the administration of caffeine may produce behavioral cross-sensitization to some psychostimulants, such as dopaminergic psychoactive drugs. Methylphenidate (MPH; Ritalin®) is a psychostimulant used in pediatric- and adult human populations to manage the symptoms associated with attention-deficit hyperactivity disorder (ADHD). Previous studies have suggested that dopamine- and cAMP-regulated phosphoproteins of 32kDa (DARPP-32) participate in the manifestation of behavioral activity following ingestion of caffeine or MPH. The aim of the present study was to evaluate whether long-term administration of low doses of caffeine in rodents during their adolescence induces cross-sensitization to MPH challenge in their adulthood and investigate the involvement of DARPP-32 in this model. Young rats (P25) consumed water or caffeine (0.3g/L; mean consumption was 7.5mg/day/kg) for 28 days. The caffeine consumption was then suspended for 14 days (washout period) when the animals received saline solution or MPH (1, 2, or 10mg/kg) (P67) intraperitoneally. The locomotor activity of these rats was assessed using the open-field test, following which the immunocontent of DARPP-32 was evaluated in samples of their prefrontal cortex, striatum, or hippocampus. Rats chronically exposed to caffeine in their adolescent period and to inactive doses of MPH (1mg/kg) in adulthood showed augmented locomotor activity. The behavioral effect observed was accompanied by increased levels of DARPP-32 in the striatum and prefrontal cortex compared to control groups (saline or caffeine). However, no alteration caused by these treatments was noted in the hippocampus. In conclusion, chronic caffeine exposure induces likely long-term cross-sensitization to MPH in a DARPP-32-dependent pathway.