SNSandra Odebrecht Vargas Nunes

Sandra Odebrecht Vargas Nunes

*This is an algorithmically generated author record based on publicly available information.

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Sandra Odebrecht Vargas Nunes has a total of 81 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Increased nitro-oxidative toxicity in association with metabolic syndrome, atherogenicity and insulin resistance in patients with affective disorders

    by Nayara Rampazzo Morelli, Michael Maes, Kamila Landucci Bonifacio, Heber Odebrecht Vargas, Sandra Odebrecht Vargas Nunes, Décio Sabbatini Barbosa


  • Towards a new model and classification of mood disorders based on risk resilience, neuro-affective toxicity, staging, and phenome features using the nomothetic network psychiatry approach

    by Michael Maes, Juliana Brum Moraes, Kamila Landucci Bonifacio, Decio Sabbatini Barbosa, Heber Odebrecht Vargas, Ana Paula Michelin, Sandra Odebrecht Vargas Nunes

    Current diagnoses of mood disorders are not cross validated. The aim of the current paper is to explain how machine learning techniques can be used to a) construct a model which ensembles risk/resilience (R/R), adverse outcome pathways (AOPs), staging, and the phenome of mood disorders, and b) disclose new classes based on these feature sets. This study was conducted using data of 67 healthy controls and 105 mood disordered patients. The R/R ratio, assessed as a combination of the paraoxonase 1 (PON1) gene, PON1 enzymatic activity, and early life time trauma (ELT), predicted the high-density lipoprotein cholesterol – paraoxonase 1 complex (HDL-PON1), reactive oxygen and nitrogen species (RONS), nitro-oxidative stress toxicity (NOSTOX), staging (number of depression and hypomanic episodes and suicidal attempts), and phenome (the Hamilton Depression and Anxiety scores and the Clinical Global Impression; current suicidal ideation; quality of life and disability measurements) scores. Partial Least Squares pathway analysis showed that 44.2% of the variance in the phenome was explained by ELT, RONS/NOSTOX, and staging scores. Cluster analysis conducted on all those feature sets discovered two distinct patient clusters, namely 69.5% of the patients were allocated to a class with high R/R, RONS/NOSTOX, staging, and phenome scores, and 30.5% to a class with increased staging and phenome scores. This classification cut across the bipolar (BP1/BP2) and major depression disorder classification and was more distinctive than the latter classifications. We constructed a nomothetic network model which reunited all features of mood disorders into a mechanistically transdiagnostic model.


  • Increased nitro-oxidative stress toxicity as a major determinant of increased blood pressure in mood disorders

    by Kamila Landucci Bonifácio, Décio Sabbatini Barbosa, Estefânia Gastaldello Moreira, Carine Farias Coneglian, Heber Odebrecht Vargas, Sandra Odebrecht Vargas Nunes, Juliana Brum Moraes, Michael Maes


  • Open Access

    Increased Nitro-Oxidative Stress Toxicity as a Major Determinant of Increased Blood Pressure in Mood Disorders

    by Kamila Landucci Bonifacio, Décio Sabbatini Barbosa, Estefânia Gastaldello Moreira, Carine Farias Coneglian, Heber Odebrecht Vargas, Sandra Odebrecht Vargas Nunes, Juliana Brum Moraes, Michael Maes

    Background: Hypertension, atherogenicity and insulin resistance are major risk factors of cardiovascular disorder (CVD), which shows a strong comorbidity with major depression (MDD) and bipolar disorder (BD). Activated oxidative and nitrosative stress (O&NS), inflammatory pathways, and increased atherogenicity are shared pathways underpinning CVD and mood disorders. Methods: The current study examined the effects of lipid hydroperoxides (LOOH), superoxide dismutase (SOD), nitric oxide metabolites (NOx), advanced oxidation protein products (AOPP), and malondialdehyde (MDA) on systolic (SBP) and diastolic (DBP) blood pressure in 96 mood disordered patients and 60 healthy controls. Results: A large part of the variance in SBP (31.6%) was explained by the regression on a z unit-weighted composite score (based on LOOH, AOPP, SOD, NOx) reflecting nitro-oxidative stress toxicity (NOSTOX), coupled with highly sensitive C-reactive protein, body weight and use of antihypertensives. Increased DBP was best predicted (23.8%) by body mass index and NOSTOX. The most important O&NS biomarkers predicting an increased SBP were in descending order of significance: LOOH, AOPP and SOD. Higher levels of the atherogenic index of plasma, HOMA2 insulin resistance index and basal thyroid-stimulating hormone also contributed to increased SBP independently from NOSTOX. Although there were no significant changes in SBP/DBP in mood disorders, the associations between NOSTOX and blood pressure were significant in patients with mood disorders but not in healthy controls. Conclusions: Activated O&NS pathways including increased lipid peroxidation and protein oxidation, which indicates hypochlorous stress, are the most important predictors of an increased BP, especially in patients with mood disorders.


  • Open Access

    Development of a Novel Staging Model for Affective Disorders Using Partial Least Squares Bootstrapping: Effects of Lipid-Associated Antioxidant Defenses and Neuro-Oxidative Stress

    by Michael Maes, Juliana Brum Moraes, Ana Congio, Kamila Landucci Bonifacio, Decio Sabbatini Barbosa, Heber Odebrecht Vargas, Ana Paula Michelin, Andre F. Carvalho, Sandra Odebrecht Vargas Nunes

    Although, staging models gained momentum to stage define affective disorders, no attempts were made to construct mathematical staging models using clinical and biomarker data in patients with major depression and bipolar disorder.The aims of this study were to use clinical and biomarker data to construct statistically-derived staging models, which are associated with early lifetime traumata (ELTs), affective phenomenology and biomarkers.In the current study, 172 subjects participated, 105 with affective disorders (both bipolar and unipolar) and 67 controls. Staging scores were computed by extracting latent vectors (LVs) from clinical data including ELTs, recurring flare ups and suicidal behaviors, outcome data such as disabilities and health-related quality of life (HR-QoL), and paraoxonase (PON)1 actvities and nitro-oxidative stress biomarkers.Recurrence of episodes and suicidal behaviors could reliably be combined into a LV with adequate composite reliability (the “recurrence LV”), which was associated with female sex, the combined effects of multiple ELTs, disabilities, HR-QoL and impairments in cognitive tests. All those factors could be combined into a reliable “ELT-staging LV” which was significantly associated with nitro-oxidative stress biomarkers. A reliable LV could be extracted from serum PON1 activities, recurrent flare ups, disabilities and HR-QoL.Our ELT-staging index scores the severity of a relevant affective dimension, shared by both major depression and bipolar disorder, namely the trajectory from ELTs, a relapsing course and suicidal behaviors to progressive disabilities. Patients were classified into three stages, namely an early stage; a relapse-regression stage; and a suicidal-regression stage. Lowered lipid-associated antioxidant defenses may be a drug target to prevent the transition from the early to the later regression stages.


  • Open Access

    Activation of the Immune-Inflammatory Response System and the Compensatory Immune-Regulatory Reflex System in Antipsychotic Naive First Episode Psychosis

    by Mariane Nunes Noto, Michael Maes, Sandra Odebrecht Vargas Nunes, Vanessa Kiyomi Ota, Ana C. Rossaneis, Waldiceu A. Verri Jr., Quirino Cordeiro, Sintia Iole Belangero, Ary Gadelha, Rodrigo Affonseca Bressan, et al.

    Background: First episode psychosis (FEP), schizophrenia and affective disorders are accompanied by activation of the immune inflammatory response system (IRS). The compensatory immune-regulatory reflex system (CIRS) is a regulatory immune response that is induced by the IRS but exerts negative feedback through, for example, increased levels of anti-inflammatory cytokines such as IL-4, IL-13 and IL-10. Different phenotypes of schizophrenia may exhibit distinct IRS and CIRS immune profiles.Aims: This study aims to examine the IRS and CIRS components, including macrophagic M1, T-helper (Th)-1, Th-2, Th-17 and T-regulatory (Treg) phenotypes, in antipsychotic-naïve FEP patients before and after risperidone treatment.Methods: We included 31 antipsychotic-naïve FEP patients who had measurements of IRS and CIRS biomarkers before and after treatment with risperidone for 10 weeks, and 22 healthy controls.Results: Antipsychotic-naive FEP patients showed interrelated increments in M1, Th-1, Th-2, Th-17 and Treg phenotypes and a relatively greater IRS response (especially granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-6 and IL-12) as compared with the CIRS response (IL-4, IL-13, IL-5 and IL-10). Inflammatory markers, especially IL-6 and IL-8, were significantly correlated with negative, psychotic, affective and excitation symptom dimensions. Treatment with risperidone significantly suppressed the IRS and CIRS. Baseline levels of CIRS biomarkers, especially higher soluble tumor necrosis factor receptor-1 and IL-10 predicted clinical improvement during treatment.Discussion: Our findings indicate that FEP is characterized by robust IRS (M1 + Th-1 + Th-17) and CIRS responses, suggesting that monocytes, macrophages, Th-1, Th-2, Th-17 and Treg cells are activated. The findings indicate that a) FEP patients are prone to the detrimental effects of M1, Th-1, Th-17 and Th-2 cells, which may contribute to long-lasting abnormalities in brain circuitry; and b) in FEP, the CIRS may contribute to recovery from the acute phase of illness. Enhancing the CIRS is a new drug target to treat FEP.


  • Open Access

    Early Life Trauma Predicts Affective Phenomenology and the Effects are Partly Mediated by Staging Coupled with Lowered Lipid-Associated Antioxidant Defences

    by Michael Maes, Ana Congio, Juliana Brum Moraes, Kamila Landucci Bonifacio, Decio Sabbatini Barbosa, Heber Odebrecht Vargas, Gerwyn Morris, Basant K. Puri, Ana Paula Michelin, Sandra Odebrecht Vargas Nunes

    Background: Early life trauma (ELT) may drive mood disorder phenomenology, neuro-oxidative and neuro-immune pathways and impairments in semantic memory. Nevertheless, there are no data regarding the impact of ELT on affective phenomenology and whether these pathways are mediated by staging or lowered lipid-associated antioxidant defences. Methods: This study examined healthy controls (n=54) and patients with affective disorders including major depression, bipolar disorder and anxiety disorders (n=118). ELT was assessed using the Child Trauma Questionnaire. In addition, we measured affective phenomenology and assayed advanced oxidation protein products; malondialdehyde, paraoxonase 1 (CMPAase) activity, high-sensitivity C-reactive protein (hsCRP), and high-density lipoprotein (HDL) cholesterol. Results: ELT was associated with increased risk for mood and comorbid anxiety disorders and a more severe phenomenology, including staging characteristics (number of mood episodes), severity of depression and anxiety, suicide attempts, suicidal ideation, type of treatments received, disabilities, body mass index, smoking behaviour and hsCRP, as well as lowered health-related quality of life, socio-economic status, antioxidant defences and semantic memory. The number of mood episodes and CMPAase/HDL-cholesterol levels could be reliably combined into a new vulnerability staging-biomarker index, which mediates in part the effects of ELT on affective phenomenology, while lowered antioxidant defences are associated with increased oxidative stress. Moreover, the effects of female sex on mood disorders and affective phenomenology are mediated by ELT. Discussion: The cumulative effects of different types of ELT drive many aspects of affective phenomenology either directly or indirectly through effects of staging and/or lipid–associated antioxidant defences. The results show that children, especially girls, with ELT are at great risk to develop mood disorders and more severe phenotypes of affective disorders.


  • In major affective disorders, early life trauma predict increased nitro-oxidative stress, lipid peroxidation and protein oxidation and recurrence of major affective disorders, suicidal behaviors and a lowered quality of life

    by Juliana Brum Moraes, Michael Maes, Chutima Roomruangwong, Kamila Landucci Bonifacio, Decio Sabbatini Barbosa, Heber Odebrecht Vargas, George Anderson, Marta Kubera, Andre F. Carvalho, Sandra Odebrecht Vargas Nunes

    Early life trauma (ELT) may increase the risk towards bipolar disorder (BD) and major depression (MDD), disorders associated with activated neuro-oxidative and neuro-nitrosative stress (O&NS) pathways. It has remained elusive whether ELTs are associated with O&NS and which ELTs are associated with distinct affective disorder phenotypes. This case-control study examined patients with BD (n = 68) and MDD (n = 37) and healthy controls (n = 66). The Child Trauma Questionnaire (CTQ) was used to assess specific ELT. We measured malondialdehyde (MDA), lipid hydroperoxides (LOOH), superoxide dismutase (SOD), catalase, advanced oxidation protein products (AOPP); NO metabolites (NOx), paraoxonase 1 activity, zinc, albumin, high density lipoprotein cholesterol and -SH groups and computed z-unit weighted composite scores. Physical neglect significantly predicts higher z-unit weighted composite scores of LOOH+SOD, LOOH+SOD+NOx, LOOH+SOD+NOx + MDA and LOOH+SOD+NOx + AOPP. Sexual abuse was associated with a significantly lower composite score of zinc+albumin+SH. Emotional abuse was associated with severity of depression and anxiety, number of depressive and manic episodes, alcohol and hypnotics use, lifetime suicidal behavior and lowered quality of life. Sexual abuse was associated with an increased risk towards BD, but not MDD. ELT, especially physical neglect, may drive increased (nitro-)oxidative stress coupled with lipid and protein oxidation, which - together with emotional abuse - may play a role in severity of illness, lowered quality of life and MDD. ELTs are also associated with the onset of BD, but this link did not appear to be related to activated O&NS pathways. These novel findings deserve confirmation in prospective studies.


  • Open Access

    Folie à Deux and its interaction with early life stress: a case report

    by Alessandra Vargas Alves Nunes, Sandra Odebrecht Vargas Nunes, Talita Strano, Gilberto Pascolat, Gustavo Manoel Schier Doria, Mauricio Nasser Ehlke

    Folie à deux is a very rare psychiatric syndrome in which a psychotic symptom is transmitted from one individual to another. We present a case of folie à deux occurring during childhood, which is not an usual presentation of this syndrome. In this case, the disorder is correlated with child abuse and neglect, which possibly had a role in the development of the symptoms in our case. We present a case of folie à deux between an “induced” 9-year-old black Brazilian boy and the “inducer”, his grandmother. They were found to be sharing similar auditory and visual hallucinations and delusional beliefs. The boy was neglected by his parents and was being cared for by his grandmother, who had a history of mental disorder. The close relationship between the boy and his grandmother, the family history of first-degree psychosis, and the child abuse and neglect suffered by the boy may have altered his vulnerability to early-onset psychosis and, in this case, folie à deux.


  • Open Access

    SLC6A4STin2 VNTR genetic polymorphism is associated with tobacco use disorder, but not with successful smoking cessation or smoking characteristics: a case control study

    by Márcia Regina Pizzo de Castro, Michael Maes, Roberta Losi Guembarovski, Carolina Batista Ariza, Edna Maria Vissoci Reiche, Heber Odebrecht Vargas, Mateus Medonça Vargas, Luiz Gustavo Piccoli de Melo, Seetal Dodd, Michael Berk, et al.

    The aim of this study was to determine if variable number of tandem repeats (VNTR) in the second intron (STin2) of the serotonin transporter (SLC6A4) gene was associated with tobacco use disorder, successful smoking cessation, or smoking characteristics. In this case–control study, patients with current tobacco use disorder, diagnosed according to DSM IV criteria (n = 185), and never-smokers, diagnosed according to CDC criteria (n = 175), were recruited and received 52 weeks of combined pharmacotherapy and cognitive therapy. Successful smoking cessation was defined as exhaled carbon monoxide < 6 ppm. SLC6A4 gene STin2 VNTR polymorphism was assessed using a Multiplex-PCR-based method. At baseline, participants were evaluated using the Fagerström Test for Nicotine Dependence (FTND) and the ASSIST scale.