Cingulate cortical thickness in cocaine use disorder: mediation effect between early life stress and cocaine consumption

OBJECTIVE

The cingulate gyrus is implicated in the neurobiology of addiction, such as chronic cocaine consumption. Early life stress (ELS) is an important moderator of cocaine use disorder (CUD). Therefore, we investigated the effect of CUD on cingulate cortical thickness and tested whether a history of ELS could influence the effects of CUD.

METHODS

Participants aged 18-50 years (78 with CUD due to crack cocaine consumption and 53 healthy controls) underwent magnetic resonance imaging and the cingulate thickness (rostral anterior, caudal anterior, posterior, and isthmus regions) was analysed. The clinical assessment comprised the Childhood Trauma Questionnaire (CTQ) and the Addiction Severity Index. Group comparisons adjusting by sex, age, and education were performed. Mediation models were generated where lifetime cocaine use, CTQ score, and cortical thickness corresponded to the independent variable, intermediary variable, and outcome, respectively.

RESULTS

Group comparisons revealed significant differences in six out of eight cingulate cortices, showing lower thickness in the CUD group. Furthermore, years of regular cocaine use was the variable most associated with cingulate thickness. Negative correlations were found between CTQ scores and the isthmus cingulate (right hemisphere), as well as with the rostral anterior cingulate (left hemisphere). In the mediation analysis, we observed a significant negative direct effect of lifetime cocaine use on the isthmus cingulate and an indirect effect of cocaine use mediated by CTQ score.

CONCLUSION

Our findings suggest that a history of ELS could aggravate the negative effects of chronic cocaine use on the cingulate gyrus, particularly in the right isthmus cingulate cortex.

Cocaine-use disorder and childhood maltreatment are associated with the activation of neutrophils and increased inflammation

BACKGROUND

Cocaine-use disorder (CUD) has been associated with early life adversity and activated cellular immune responses. Women are most vulnerable to complications from chronic substance disorders, generally presenting an intense feeling of abstinence and consuming significant drug amounts. Here, we investigated neutrophil functional activities in CUD, including the formation of neutrophil extracellular traps (NETs) and related intracellular signalling. We also investigated the role of early life stress in inflammatory profiles.

METHODS

Blood samples, clinical data, and history of childhood abuse or neglect were collected at the onset of detoxification treatment of 41 female individuals with CUD and 31 healthy controls (HCs). Plasma cytokines, neutrophil phagocytosis, NETs, intracellular reactive oxygen species (ROS) generation, and phosphorylated protein kinase B (Akt) and mitogen-activated protein kinases (MAPK)s were assessed by flow cytometry.

RESULTS

CUD subjects had higher scores of childhood trauma than controls. Increased plasma cytokines (TNF-α, IL-1β, IL-6, IL-8, IL-12, and IL-10), neutrophil phagocytosis, and production of NETs were reported in CUD subjects as compared to HC. Neutrophils of CUD subjects also produced high levels of intracellular ROS and had more activated Akt and MAPKs (p38/ERK), which are essential signalling pathways involved in cell survival and NETs production. Childhood trauma scores were significantly associated with neutrophil activation and peripheral inflammation.

CONCLUSION

Our study reinforces that smoked cocaine and early life stress activate neutrophils in an inflammatory environment.

A single dose of cocaine raises SV2A density in hippocampus of adolescent rats

OBJECTIVE

Cocaine is a highly addictive psychostimulant that affects synaptic activity with structural and functional adaptations of neurons. The transmembrane synaptic vesicle glycoprotein 2A (SV2A) of pre-synaptic vesicles is commonly used to measure synaptic density, as a novel approach to the detection of synaptic changes. We do not know if a single dose of cocaine suffices to affect pre-synaptic SV2A density, especially during adolescence when synapses undergo intense maturation. Here, we explored potential changes of pre-synaptic SV2A density in target brain areas associated with the cocaine-induced boost of dopaminergic neurotransmission, specifically testing if the effects would last after the return of dopamine levels to baseline.

METHODS

We administered cocaine (20 mg/kg i.p.) or saline to rats in early adolescence, tested their activity levels and removed the brains 1 hour and 7 days after injection. To evaluate immediate and lasting effects, we did autoradiography with [3H]UCB-J, a specific tracer for SV2A, in medial prefrontal cortex, striatum, nucleus accumbens, amygdala, and dorsal and ventral areas of hippocampus. We also measured the striatal binding of [3H]GBR-12935 to test cocaine's occupancy of the dopamine transporter at both times of study.

RESULTS

We found a significant increase of [3H]UCB-J binding in the dorsal and ventral sections of hippocampus 7 days after the cocaine administration compared to saline-injected rats, but no differences 1 hour after the injection. The [3H]GBR-12935 binding remained unchanged at both times.

CONCLUSION

Cocaine provoked lasting changes of hippocampal synaptic SV2A density after a single exposure during adolescence.

Prenatal cocaine exposure and its influence on pediatric epigenetic clocks and epigenetic scores in humans

The investigation of the effects of prenatal cocaine exposure (PCE) on offspring has been inconsistent, with few studies investigating biological outcomes in humans. We profiled genome-wide DNA methylation (DNAm) of umbilical cord blood (UCB) from newborns with (n = 35) and without (n = 47) PCE. We used DNAm data to (1) assess pediatric epigenetic clocks at birth and (2) to estimate epigenetic scores (ES) for lifetime disorders. We generated gestational epigenetic age estimates (DNAmGA) based on Knight and Bohlin epigenetic clocks. We also investigated the association between DNAmGA and UCB serum brain-derived neurotrophic factor (BDNF) levels. Considering the large-scale DNAm data availability and existing evidence regarding PCE as a risk for health problems later in life, we generated ES for tobacco smoking, psychosis, autism, diabetes, and obesity. A gene ontology (GO) analysis on the CpGs included in the ES with group differences was performed. PCE was associated with lower DNAmGA in newborns, and this effect remained significant when controlling for potential confounders, such as blood cell type composition predicted by DNAm and obstetric data. DNAmGA was negatively correlated with BDNF levels in the serum of UCB. Higher tobacco smoking, psychosis, and diabetes ES were found in the PCE group. The GO analysis revealed GABAergic synapses as a potential pathway altered by PCE. Our findings of decelerated DNAmGA and ES for adverse phenotypes associated with PCE, suggest that the effects of gestational cocaine exposure on the epigenetic landscape of human newborns are detectable at birth.

Proposing an integrative, dynamic and transdiagnostic model for addictions: dysregulation phenomena of the three main modes of the predostatic mind

Several theories have been proposed to explain the complex diagnostic aspects related to addiction disorders and their development. Recent frameworks tend to focus on dimensional perspectives of symptoms rather than categorical systems, since substance use disorders are frequently comorbid with other psychiatric and especially personality disorders. However, useful transdiagnostic models that could integrate clinical evaluation derived from neuroscientific theories are lacking. In the present manuscript, the authors propose a model based on a new paradigm, in an attempt to better explain this complex, multifaceted phenomenon. The new paradigm presupposes that emotions and behavior are a response to risk prediction. Individuals make choices and engage in actions to manage potential risks/rewards in order to seek or maintain homeostasis in their internal and external environments - a mechanism that the authors call predostatic (predictive mechanism with homeostatic purpose). The model considers three main modes of the predostatic mind: (1) Alarm Mode, activated by high and/or imminent risk prediction; (2) Seek Mode, activated by long-term risk or reward prediction; and (3) Balance Mode, a self-regulating state of mind related to low risk prediction, a soothing system and a calm state. Addiction is seen as a chronic dysregulation of organism systems leading to internalizing or externalizing phenomena mainly related to the Seek and Alarm Modes, which are persistently activated by reward and risk prediction, respectively, thus hindering Balance. Addiction neuroscience research has shown that chronic drug use or engagement in addictive behaviors can lead to neuroadaptations in the brain reward circuitry, disrupting normal balance and the regulation of reward processes. This dysregulation can contribute to persistent drug-seeking/addictive behaviors despite negative consequences. This newly proposed dynamic and integrative model, named dysregulation based on externalizing and internalizing phenomena of the three main modes of the predostatic mind (DREXI3), proposes six dysregulation dimensions with basic emotional and behavioral symptoms, such as neurophysiological alterations, impulsivity, compulsion, cognitive impairment/psychosis, mood, and anxiety/anger. In this paper, the authors explain the rationale behind DREXI3 and present some hypothetical clinical examples to better illustrate the use of the model in clinical practice. The development of this innovative model could possibly guide tailored treatment interventions in the addiction field.

The cortical thickness of tricenarian cocaine users assembles features of an octogenarian brain

It has been suggested that substance use disorders could lead to accelerated biological aging, but only a few neuroimaging studies have investigated this hypothesis so far. In this cross-sectional study, structural neuroimaging was performed to measure cortical thickness (CT) in tricenarian adults with cocaine use disorder (CUD, n1  = 30) and their age-paired controls (YC, n1  = 30), and compare it with octogenarian elder controls (EC, n1  = 20). We found that CT in the right fusiform gyrus was similar between CUD and EC, thinner than the expected values of YC. We also found that regarding CT of the right inferior temporal gyrus, right inferior parietal cortex, and left superior parietal cortex, the CUD group exhibited parameters that fell in between EC and YC groups. Finally, CT of the right pars triangularis bordering with orbitofrontal gyrus, right superior temporal gyrus, and right precentral gyrus were reduced in CUD when contrasted with YC, but those areas were unrelated to CT of EC. Despite the 50-year age gap between our age groups, CT of tricenarian cocaine users assembles features of an octogenarian brain, reinforcing the accelerated aging hypothesis in CUD.

Examining predictors of cocaine withdrawal syndrome at the end of detoxification treatment in women with cocaine use disorder

BACKGROUND

Detoxification is frequently recommended as a treatment for moderate to severe Cocaine Use Disorder (CUD). However, the response to detoxification varies among patients, and previous studies have focused mostly on patterns of drug use behavior to test associations with treatment outcomes, overlooking the potential impact of psychosocial factors, other clinical variables, and individual life experiences. In this study we comprehensively examined several variables aiming to find the most relevant predictors to classify patients with severe versus non-severe cocaine withdrawal symptoms at the end of detoxification.

METHODS

Data from 284 women with CUD who enrolled in a 3-week detoxification program was used in this longitudinal study. Psychosocial, clinical, and drug use behavior characteristics were evaluated, generating a dataset with 256 potential predictors. We tested six different machine learning classification algorithms.

RESULTS

The best classification algorithm achieved an average accuracy and ROC-AUC of approximately 70%. The 16 features selected as best predictors were the severity of psychiatric, family, and social problems and the level of exposure to childhood maltreatment. Features associated with drug-use behavior included days consuming drugs and having craving symptoms in the last month before treatment, number of previous drug/alcohol-related treatments, and a composite score of addiction severity. The level of cocaine withdrawal syndrome at the beginning of detoxification was also a key feature for classification. A network analysis revealed the pattern of association between predictors.

CONCLUSION

These variables can be assessed in real-world clinical settings, potentially helping clinicians to identify individuals with severe cocaine withdrawal that is likely to be sustained over the course of detoxification.

Vulnerability and resilience to prenatal stress exposure: behavioral and molecular characterization in adolescent rats

Exposure to stress can lead to long lasting behavioral and neurobiological consequences, which may enhance the susceptibility for the onset of mental disorders. However, there are significant individual differences in the outcome of stress exposure since only a percentage of exposed individuals may show pathological consequences, whereas others appear to be resilient. In this study, we aimed to characterize the effects of prenatal stress (PNS) exposure in rats at adolescence and to identify subgroup of animals with a differential response to the gestational manipulation. PNS adolescent offspring (regardless of sex) showed impaired emotionality in different pathological domains, such as anhedonia, anxiety, and sociability. However, using cluster analysis of the behavioral data we could identify 70% of PNS-exposed animals as vulnerable (PNS-vul), whereas the remaining 30% were considered resilient (PNS-res). At the molecular level, we found that PNS-res males show a reduced basal activation of the ventral hippocampus whereas other regions, such as amygdala and dorsal hippocampus, show significant PNS-induced changes regardless from vulnerability or resilience. Taken together, our results provide evidence of the variability in the behavioral and neurobiological effects of PNS-exposed offspring at adolescence. While these data may advance our understanding of the association between exposure to stress during gestation and the risk for psychopathology, the investigation of the mechanisms associated to stress vulnerability or resilience may be instrumental to develop novel strategies for therapeutic intervention.

Cocaine use disorder effects on blood oxytocin levels and OXTR DNA methylation

Substance use disorders have been associated with alterations in the oxytocinergic system, but few studies have investigated both the peptide and epigenetic mechanisms potentially implicated in the regulation of oxytocin receptor. In this study, we compared plasma oxytocin and blood DNA methylation in the OXTR gene between people with and without cocaine use disorder (CUD). We measured the oxytocin levels of 51 people with CUD during acute abstinence and of 30 healthy controls using an enzyme immunoassay. The levels of DNA methylation in four CpG sites at exon III of the OXTR gene were evaluated in a subsample using pyrosequencing. The Addiction Severity Index was used to assess clinical characteristics. We found higher oxytocin levels in men with CUD (56.5 pg/mL; 95% CI: 48.2-64.7) than in control men (33.6 pg/mL; 95% CI: 20.7-46.5), while no differences between women with and without CUD were detected. With a moderate effect size, the interaction effect between group and sex remained significant when controlling for height, weight and age data. A positive correlation in the CUD sample was found between oxytocin levels and days of psychological suffering prior to treatment enrollment. No group differences were observed regarding DNA methylation data. This suggests that CUD is associated with higher peripheral oxytocin levels in men during acute abstinence. This finding may be considered in future studies that aim at using exogenous oxytocin as a potential treatment for cocaine addiction.

Can early-life high fructose exposure induce long-term depression and anxiety-like behaviours? - A preclinical systematic review

Early-life environmental factors, such as maternal diet or early-life nutrition, have been described as significant risk factors for anxiety and depression later in life. With the rising intake of fructose since the 1960 s, several adverse effects have been described, but little is known about the impact of early-life high fructose exposure on the risk of developing depression and anxiety later in life. Since animal models provide ways to test this hypothesis longitudinally in an experimental and controlled environment, we performed a systematic review to investigate whether high fructose exposure during early life influences the risk of developing depression or anxiety-like behaviours in animals. We adopted a high-sensitivity strategy to find potential studies. We included 1805 papers for screening, but only found nine eligible studies that tested only high fructose exposure during development, all conducted in rats. Data extraction and analysis revealed that 6 studies found evidence indicating that fructose exposure in early life increases the risk of anxiety or depression. The remaining 3 studies found no altered behavior after fructose exposure. The discrepancies may be caused by multiple factors, such as time of diet exposure, animal strain, behavioural testing differences, and fructose's metabolic influence. Due to weak and contradictory evidence, we could not conclude if early-life fructose exposure influences the risk of anxiety or depression-like behaviors. We propose future directions and suggestions for future studies to strengthen their findings.

A systematic review and multilevel meta-analysis of the prenatal and early life stress effects on rodent microglia, astrocyte, and oligodendrocyte density and morphology

Exposure to stress during early development may lead to altered neurobiological functions, thus increasing the risk for psychiatric illnesses later in life. One potential mechanism associated with those outcomes is the disruption of glial density and morphology, despite results from rodent studies have been conflicting. To address that we performed a systematic review and meta-analysis of rodent studies that investigated the effects of prenatal stress (PNS) and early life stress (ELS) on microglia, astrocyte, and oligodendrocyte density and morphology within the offspring. Our meta-analysis demonstrates that animals exposed to PNS or ELS showed significant increase in microglia density, as well as decreased oligodendrocyte density. Moreover, ELS exposure induced an increase in microglia soma size. However, we were unable to identify significant effects on astrocytes. Meta-regression indicated that experimental stress protocol, sex, age, and type of tissue analyzed are important covariates that impact those results. Importantly, PNS microglia showed higher estimates in young animals, while the ELS effects were stronger in adult animals. This set of data reinforces that alterations in glial cells could play a role in stress-induced dysfunctions throughout development.

A cross-sectional study of the association between exposure to violence, intelligence, and executive function in Brazilian youths

We carried out an exploratory study of the association between exposure to violence, intelligence, and executive functions in Brazilian preadolescents. The study included 56 participants (31 males) aged 8 to 14 years old (mean = 11.3, SD = 1.0). We administered neuropsychological tests to evaluate executive functions and the Juvenile Victimization Questionnaire (JVQ) to evaluate exposure to violence. We used the following neuropsychological instruments: Wechsler Abbreviated Scale of Intelligence (WASI), Stroop Color-Word Interference task, digits subtest of the Wechsler Intelligence Scale for Children, and an N-back task. We generated a composite score from neuropsychological test scores and investigated the association of that score, and individual test scores, with exposure to violence and socioeconomic status (SES). Results suggest, first, that exposure to violence is associated with a 0.5-point lower intelligence quotient score for every reported victimization event in the Juvenile Victimization Questionnaire. Results also show that the digits backward subtest scores showed a significant negative correlation with exposure to violence (JVQ; rho = -0.29, p < 0.05); both analyses were adjusted for the level of schooling of parents or guardians, which was also found to be significantly associated with lower intelligence quotient scores. We discuss results in the light of the existing literature on the effects of exposure to violence on adolescent development, and the amounting evidence that suggests an association of exposure to violence, and of victimization, with tests that evaluate constructs of executive functions. The study struggled with low compliance from participants, and we underscore the challenges of carrying out empirical studies aimed at better understanding the development of underrepresented youths, such as those from Central and Latin America.

Decision-making under risk and theory of mind in adolescent offenders in provisional deprivation of liberty

INTRODUCTION

Delinquent behaviors are risky behaviors that increase during puberty and reach their highest peak in late adolescence. It has been proposed that poor decision-making and theory of mind (ToM) are key cognitive processes implicated with delinquency during adolescence, affecting evaluation of risks and impairing appreciation of social norms. Nevertheless, it is not yet clear whether adolescent offenders who are subjected to provisional deprivation of liberty due to conflict with the law (adolescents in conflict with the law [ACL]) might, in fact, present a specific profile with regard to these cognitive processes.

OBJECTIVES

To assess deliberative decision-making and ToM among adolescents in conflict with the law and adolescents not in conflict with the law.

METHODS

The sample comprised 62 participants: ACL (n = 29) and a control group (CG) (n = 33). ToM was assessed with the Reading the Mind in the Eyes Test (RMET) and decision-making was assessed with the Columbia Card Task (CCT). Substance use, callous-unemotional traits, childhood maltreatment, and intelligence quotient (IQ) were also assessed.

RESULTS

ACL had more ToM errors for negative mental states in comparison to CG, but not for error rates concerning neutral and positive mental states. With regards to decision-making, our results suggest that ACL group members did not vary their behavior based on the available information and that the risk information had an opposite effect on the number of cards chosen (risk-taking behavior) when compared to CG.

CONCLUSION

These findings have important implications for development of interventions for these adolescents, suggesting that they tend to learn little from negative outcomes and have reduced capacity to process negative emotions.

Rethinking treatment-resistant depression to quasi-tenacious depression

With almost one-third of patients with major depression not adequately responsive to treatments, the management of treatment-resistant depression (TRD) has continued to be challenging. Recently, an essential step was taken to replace TRD with difficult-to-treat depression (DTD), pointing to some drawbacks associated with this terminology and identifying addressable barriers. In line with the DTD concept, we discuss why terming this population of patients as TRD could be semantically and clinically misleading. We then suggest replacing TRD with quasi-tenacious depression (QTD), a model and terminology that are derived from a potentially measurable outcome, the tenacity index (TI). QTD predicts that in theory remission is achievable by providing suitable treatments at hand. QTD states that every patient with major depression (even those who respond well) has some degree of tenacity that needs to be overcome by the use of proper treatment modalities. Ergo, in patients with a higher TI, due to the dearth of available armamentaria, one might suffice to achieve a partial resolution of symptoms balanced with an optimal quality of life. However, QTD calls for an incessant pursuit of novel treatments and the identification of contributing factors leading to high TI. On a track toward personalized psychiatry, and in harmony with DTD, QTD embraces all key barriers leading to a failure to treatment response and tries to provide a measurable entity for a better clinical decision while conveying a dynamic positive outlook of the disorder for both patients and health care providers.

Effects of substance use disorder on oxidative and antioxidative stress markers: A systematic review and meta-analysis

Recently, it has been suggested that central and peripheral toxicities identified in persons with substance use disorder (SUD) could be partially associated with an imbalance in reactive oxygen species and antioxidant defenses. We conducted a systematic review and meta-analysis to investigate whether SUD is associated with oxidative stress and to identify biomarkers possibly more affected by this condition. We have included studies that analysed oxidant and antioxidant markers in individuals with SUD caused by stimulants, alcohol, nicotine, opioids, and others (cannabis, inhalants, and polysubstance use). Our analysis showed that persons with SUD show higher oxidant markers and lower antioxidant markers than healthy controls. SUD was associated specifically with higher levels of oxidant markers malondialdehyde, thiobarbituric acid reactive substances and lipid peroxidation. Conversely, the antioxidant superoxide dismutase and the total antioxidant capacity/status were lowered in the SUD group. A meta-regression analysis revealed that persons with alcohol use disorder had higher oxidative stress estimates than those with stimulant use disorder. Moreover, individuals evaluated during abstinence showed smaller antioxidant effect sizes than non-abstinent ones. Our findings suggest a clear oxidative imbalance in persons with SUD, which could lead to cell damage and result in multiple associated comorbidities, particularly accelerated aging.

A systematic review and meta-analysis of epigenetic clocks in schizophrenia

INTRODUCTION

Evidence suggests that schizophrenia (SZ) is associated with accelerated biological aging. DNA methylation can be used as an indicator of biological aging by means of epigenetic clock estimates.

OBJECTIVE

The aim of this systematic review and meta-analysis was to investigate the association between SZ and different epigenetic clocks.

METHODS

Search terms were applied in different databases: Embase, MEDLINE (EBSCO), Cochrane Central Register of Controlled Trials, PubMed, PsychINFO and Web of Science. To assess for risk of bias we utilized an adapted version of the Newcastle-Ottawa Scale. Meta-analyses were conducted using the random effects model and meta-regressions were used to assess factors associated with heterogeneity.

RESULTS

Eight studies were included (Controls, n = 3394; SZ subjects, n = 3096), which analyzed five different epigenetic clocks. Overall meta-analysis revealed no significant differences between SZ and controls on epigenetic aging (Standardized Mean Difference - SMD = -0.21; p = 0.13). However, epigenetic clock method was a significant moderator of heterogeneity (p = 0.004). Using Horvath's clock as reference, higher SMD's were found for PhenoAge and Intrinsic epigenetic age acceleration (IEAA) clocks. In a stratified meta-analysis restricted to the two clocks mentioned above, a significant accelerating effect was found in patients with SZ when compared to controls (SMD = 0.29; p = 0.003).

CONCLUSION

Our findings suggest that the method of epigenetic clocks is a critical factor associated with estimates of aging acceleration in SZ. However, more studies are needed to confirm these findings and in order to evaluate a possible minor effect in overall analysis.

Validation of the Brazilian Portuguese version of the Quick Inventory of Depressive Symptomatology and Self-Report (QIDS-SR16) for the Brazilian population

OBJECTIVES

To evaluate the psychometric properties of the Quick Inventory of Depressive Symptomatology (QID-SR16), a self-report instrument based on the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) criteria that assesses the severity of depression symptoms, in the Brazilian population.

METHODS

Participants were 4,400 Brazilians over the age of 15 years recruited for an online survey assessing depressive symptoms during the early phase of the coronavirus disease 2019 (COVID-19) pandemic in Brazil. The internal consistency, construct validity, and convergent and discriminant validity of the QIDS-SR16 were evaluated.

RESULTS

The model tested was considered an adequate fit to the data (comparative fit index [CFI] = 0.947, Tucker-Lewis index [TLI] = 0.927, and root-mean-square error of approximation [RMSEA] = 0.051) and its internal consistency was good, with a Cronbach's alpha of 0.71 and an average item correlation of 0.23. The correlations between the total QIDS-SR16 score and the total scores of the Patient Health Questionnaire (PHQ-9) instruments (r = 0.67, p < 0.001), the Posttraumatic Symptoms Checklist (PCL-5) (r = 0.61, p < 0.001), and the Patient-Reported Outcomes Measurement Information System (PROMIS) (r = 0.60, p < 0.001) indicate good concurrent and convergent validity.

CONCLUSION

The QIDS-SR16 has robust psychometric properties in terms of its internal consistency, construct validity, and convergent and discriminant validity. The Portuguese version of the QIDS-SR16 is an adequate instrument for assessment of depressive symptoms in the context of an online survey.

Validation of the Brazilian Portuguese version of the Quick Inventory of Depressive Symptomatology and Self-Report (QIDS-SR16) for the Brazilian population

OBJECTIVE

The aim of this study was to evaluate the psychometric properties of the Quick Inventory of Depressive Symptomatology (QID-SR16), a self-report instrument based on the DSM-IV criteria that assesses the severity of depression symptoms, in the Brazilian population.

METHOD

Participants were 4.400 Brazilians over 15 years old recruited from an online survey assessing depressive symptoms during the early phase of COVID-19 pandemic in Brazil. Internal consistency, construct validity and convergent and discriminant validity of the QIDS-SR16 were evaluated.

RESULTS

The tested model was considered adequate to the data (CFI = 0.947, TLI = 0.927 and RMSEA = 0.051) and its internal consistency was good, with a cronbach's alpha of 0.71 and an average item correlation of 0.23. The correlations between the total score of the QIDS-SR16 and the total scores of the PHQ-9 instruments (r = 0.67, p < 0.001), PCL-5 (r = 0.61, p < 0.001) and PROMIS (r = 0.60, p < 0.001) demonstrate good indicators of concurrent and convergent validity.

CONCLUSION

The psychometric properties of the QIDS-SR16 proved to be strong in terms of internal consistency, construct validity, and convergent and discriminant validity. The Portuguese version of QIDS-SR16 is an adequate instrument to assess depressive symptoms in the context of an online survey.

Gender differences in progression to crack-cocaine use and the role of sexual and physical violence

Objective:

This study aimed to evaluate whether progression from first drug use to crack-cocaine use differs according to gender, and whether the report of sexual or physical violence impacts the time of progression.

Methods:

We interviewed 896 crack-cocaine users (548 men; 348 women) from addiction treatment units. Cox regression models evaluated the time of progression from first drug use to crack use. We analyzed gender differences according to the absence or presence of sexual or physical violence, also considering whether violence, when present, had occurred before or after the onset of crack use.

Results:

Women presented a faster progression to crack use regardless of exposure to sexual or physical violence (p < 0.05). Compared to unexposed men, there was a similar progression for men exposed to sexual or physical violence before the first use of crack (p = 0.167 and p = 0.393, respectively). In both genders, we observed a faster progression among individuals exposed to these types of violence after the onset of crack use (p < 0.01).

Conclusions:

We found a faster progression to crack use among women and among individuals exposed to sexual and physical violence after the onset of crack use. These results encourage differentiated treatment strategies, focused on gender and individual characteristics.

Sex differences in risk behavior parameters in adolescent mice: Relationship with brain-derived neurotrophic factor in the medial prefrontal cortex

Adolescence is as a period of development characterized by impulsive and risk-seeking behaviors. Risk behaviors (RB) involves exposure to dangerous or negative consequences to achieve goal-directed behaviors, such as reward-seeking. On the other hand, risk aversion/assessment behaviors allow the individual to gather information or avoid potentially threatening situations. Evidence has suggested that both behavioral processes, RB and risk assessment (RA), may have sex-differences. However, sex-specific behavioral patterns implicated in RB and RA are not fully understood. To address that, we investigated sex differences in risk-behavioral parameters in a decision-making task developed for rodents. In addition, we investigated the potential role of sex-dependent differences in gene expression of brain-derived neurotrophic factor (BDNF) exon IV in the medial prefrontal cortex (mPFC), which has been implicated to mediate PFC-related behavioral dysfunctions. Male and female C57BL/6J adolescent mice were evaluated in the elevated plus-maze (EPM) to assess anxiety-like behaviors and in the predator-odor risk taking (PORT) task. The PORT task is a decision-making paradigm in which a conflict between the motivation towards reward pursuit and the threat elicited by predatory olfactory cues (coyote urine) is explored. After behavioral testing, animals were euthanized and BDNF exon IV gene expression was measured by RT-qPCR. Comparative and correlational analyses for behavioral and molecular parameters were performed for both sexes. We observed that female mice spent more time exploring the middle chamber of the PORT apparatus in the aversive condition, which is an indicative of avoidance behavior. Female mice also had a higher latency to collect the reward than male mice and presented less time exploring the open arms of the EPM. BDNF exon IV gene expression was higher among females, and there was a positive correlation between the BDNF and PORT behavioral parameters. Our findings suggest sex-dependent effects in the PORT task. Females presented higher RA and avoidance behavior profile and expressed higher levels of BDNF exon IV in the mPFC. Moreover, higher BDNF expression was correlated with RA behaviors, which suggests that adolescent females tend to evaluate the risks more than adolescent males and that BDNF gene expression may be mediating decision-making processes.

The Perceptions of Women About Their High Experience of Using Crack Cocaine

INTRODUCTION

The aim of this study was to explore the perceptions of women about their experience in using crack cocaine, discussing their motivations for using it and the repercussions in their lives.

OBJECTIVE

To investigate these experiences, a qualitative exploratory study was conducted, using the inductive thematic analyses of the content.

METHODS

Eight female crack cocaine users took part in this study. They were assessed by a semi-structured interview, addressing the crack cocaine use experience. Four main themes emerged in the interviews: (1) crack cocaine "high" experience; (2) symptoms related to crack cocaine use; (3) circumstances of crack cocaine use; and (4) crack cocaine use consequences.

RESULTS

The main perceptions reported by the users were related to a feeling of being disconnected to the world preceded by a pleasant experience, especially during the first moments of use. They revealed that the drug fulfills a key role of coping strategy to handle with negative thoughts, emotions or life experiences. An important influence of social issues was reported in relation to the onset of crack cocaine use. Negative consequences and significant impact on their lives appeared in their reports, regarding the loss of family ties, involvement with prostitution, traumatic experiences and violence.

CONCLUSION

Taking together all women's perceptions suggests that beyond the positive immediate rewarding effect, the maintenance of use might be related to the dissociative experience and self-medication role, acting as negative reward by relieving of negative life experiences that, in turn, are both cause and consequence of the drug use.

Gestational stress alters maternal behavior and inflammatory markers in the olfactory bulb of lactating mice

Inflammatory markers represent important candidates responsible for the altered behavior and physiology observed after stressful experiences. In the maternal brain, the olfactory bulb (OB) is a key constituent of the neural circuit that mediates the reciprocal interaction between mother and infant. This study aimed to investigate the effects of stress during pregnancy on maternal behavior and inflammatory changes in the olfactory bulb of lactating mice. Female Balb/c mice were divided into two groups: control (CT) and restraint stress (RS). Maternal behavior was performed during the first 8 days of life of the offspring. On the 10th day after parturition, corticosterone, gene, and protein expression were assessed. Stress during pregnancy decreased the maternal index at postnatal day 4 and the nuclear factor-κB 1 (NFκB1) gene expression in the OB. Moreover, females from the RS group showed increased interleukin (IL-1β) protein expression. In contrast, stressed females exhibited a decreased tumor necrosis factor (TNF-α) protein expression in the OB. In conclusion, exposure to stress during pregnancy was able to induce specific postnatal effects on maternal behavior and balance of inflammatory mediators in the OB.

Oxytocin Receptor Exon III Methylation in the Umbilical Cord Blood of Newborns With Prenatal Exposure to Crack Cocaine

BACKGROUND

Prenatal cocaine exposure (PCE) is associated with behavioral, cognitive, and social consequences in children that might persist into later development. However, there are still few data concerning epigenetic mechanisms associated with the effects of gestational cocaine exposure, particularly in human newborns.

AIMS

We investigated the effects of PCE on DNA methylation patterns of the Oxytocin Receptor (OXTR) gene in the umbilical cord blood (UCB). The relationship between UCB DNA methylation levels and the severity of the mother's cocaine use during pregnancy was also evaluated.

METHODS

In this cross-sectional study, 28 UCB samples of newborns with a history of crack cocaine exposure in utero and 30 UCB samples of non-exposed newborns (NEC) were compared for DNA methylation levels at two genomic loci located in exon III of the OXTR gene (OXTR1 and OXTR2) through pyrosequencing. Maternal psychopathology was investigated using the Mini International Neuropsychiatric Interview, and substance use characteristics and addiction severity were assessed using the Smoking and Substance Involvement Screening Test (ASSIST).

RESULTS

No differences between newborns with a history of PCE and NEC were observed in OXTR1 or OXTR2 DNA methylation levels. However, regression analyses showed that maternal addiction severity for crack cocaine use predicted OXTR1 DNA methylation in newborns.

CONCLUSION

These data suggest that OXTR methylation levels in the UCB of children are affected by the severity of maternal crack cocaine usage. Larger studies are likely to detect specific changes in DNA methylation relevant to the consequences of PCE.

Exposure to Prenatal Stress Is Associated With an Excitatory/Inhibitory Imbalance in Rat Prefrontal Cortex and Amygdala and an Increased Risk for Emotional Dysregulation

Epidemiological studies have shown that environmental insults and maternal stress during pregnancy increase the risk of several psychiatric disorders in the offspring. Converging lines of evidence from humans, as well as from rodent models, suggest that prenatal stress (PNS) interferes with fetal development, ultimately determining changes in brain maturation and function that may lead to the onset of neuropsychiatric disorders. From a molecular standpoint, transcriptional alterations are thought to play a major role in this context and may contribute to the behavioral phenotype by shifting the expression of genes related to excitatory and inhibitory (E/I) transmission balance. Nevertheless, the exact neurophysiological mechanisms underlying the enhanced vulnerability to psychopathology following PNS exposure are not well understood. In the present study, we used a model of maternal stress in rats to investigate the distal effects of PNS on the expression of genes related to glutamatergic and GABAergic neurotransmissions. We inspected two critical brain regions involved in emotion regulation, namely, the prefrontal cortex (PFC) and the amygdala (AMY), which we show to relate with the mild behavioral effects detected in adult rat offspring. We observed that PNS exposure promotes E/I imbalance in the PFC of adult males only, by dysregulating the expression of glutamatergic-related genes. Moreover, such an effect is accompanied by increased expression of the activity-dependent synaptic modulator gene Npas4 specifically in the PFC parvalbumin (PV)-positive interneurons, suggesting an altered regulation of synapse formation promoting higher PV-dependent inhibitory transmission and increased overall circuit inhibition in the PFC of males. In the AMY, PNS more evidently affects the transcription of GABAergic-related genes, shifting the balance toward inhibition. Collectively, our findings suggest that the E/I dysregulation of the PFC-to-AMY transmission may be a long-term signature of PNS and may contribute to increase the risk for mood disorder upon further stress.

Long-lasting effects of prenatal stress on HPA axis and inflammation: A systematic review and multilevel meta-analysis in rodent studies

Exposure to prenatal stress (PNS) can lead to long-lasting neurobiological and behavioral consequences for the offspring, which may enhance the susceptibility for mental disorders. The hypothalamus-pituitary-adrenal (HPA) axis and the immune system are two major factors involved in the stress response. Here, we performed a systematic review and meta-analysis of rodent studies that investigated the effects of PNS exposure on the HPA axis and inflammatory cytokines in adult offspring. Our analysis shows that animals exposed to PNS display a consistent increase in peripheral corticosterone (CORT) levels and central corticotrophin-releasing hormone (CRH), while decreased levels of its receptor 2 (CRHR2). Meta-regression revealed that sex and duration of PNS protocol are covariates that moderate these results. There was no significant effect of PNS in glucocorticoid receptor (GR), CRH receptor 1 (CRHR1), pro- and anti-inflammatory cytokines. Our findings suggest that PNS exposure elicits long-lasting effects on the HPA axis function, providing an important tool to investigate in preclinical settings key pathological aspects related to early-life stress exposure. Furthermore, researchers should be aware of the mixed outcomes of PNS on inflammatory markers in the adult brain.

Cortical thickness and subcortical volume abnormalities in male crack-cocaine users

Crack-cocaine offers a higher risk of abuse than intranasal and intravenous use of cocaine. Yet, current treatments remain disappointing and our understanding of the mechanism of crack-cocaine neurotoxicity is still incomplete. Magnetic resonance images studies on brain changes of crack-cocaine addicts show divergent data. The present study investigated gray matter (GM) abnormalities in crack-cocaine dependents (n = 18) compared to healthy controls (n = 17). MRI data was analysed using FreeSurfer and voxel-based morphometry (VBM). FreeSurfer analysis showed that CD had decreased cortical thickness (CT) in the left inferior temporal cortex (lTC), left orbitofrontal cortex (lOFC) and left rostro frontal cortex (lRFC), enlargement in left inferior lateral ventricle, and smaller GM volume in right hippocampus and right ventral diencephalon. VBM analysis showed that CD had significantly decreased GM volume in left Putamen and left nucleus accumbens. Furthermore, we found a negative correlation between duration of crack-cocaine use and lTC CT. These results provide compelling evidence for GM abnormalities in CD and also suggest that duration of crack-cocaine use may be associated with CT alterations.

White matter deficits in cocaine use disorder: convergent evidence from in vivo diffusion tensor imaging and ex vivo proteomic analysis

White matter (WM) abnormalities in patients with cocaine use disorder (CUD) have been studied; however, the reported effects on the human brain are heterogenous and most results have been obtained from male participants. In addition, biological data supporting the imaging findings and revealing possible mechanisms underlying the neurotoxic effects of chronic cocaine use (CU) on WM are largely restricted to animal studies. To evaluate the neurotoxic effects of CU in the WM, we performed an in vivo diffusion tensor imaging assessment of male and female cocaine users (n = 75) and healthy controls (HC) (n = 58). Moreover, we performed an ex vivo large-scale proteomic analysis using liquid chromatography-tandem mass spectrometry in postmortem brains of patients with CUD (n = 8) and HC (n = 12). Compared with the HC, the CUD group showed significant reductions in global fractional anisotropy (FA) (p < 0.001), and an increase in global mean (MD) and radial diffusion (RD) (both p < 0.001). The results revealed that FA, RD, and MD alterations in the CUD group were widespread along the major WM tracts, after analysis using the tract-based special statistics approach. Global FA was negatively associated with years of CU (p = 0.0421) and female sex (p < 0.001), but not with years of alcohol or nicotine use. Concerning the fibers connecting the left to the right prefrontal cortex, Brodmann area 9 (BA9), the CUD group presented lower FA (p = 0.006) and higher RD (p < 0.001) values compared with the HC group. A negative association between the duration of CU in life and FA values in this tract was also observed (p = 0.019). Proteomics analyses in BA9 found 11 proteins differentially expressed between cocaine users and controls. Among these, were proteins related to myelination and neuroinflammation. In summary, we demonstrate convergent evidence from in vivo diffusion tensor imaging and ex vivo proteomics analysis of WM disruption in CUD.

A behavioral economic risk aversion experiment in the context of the COVID-19 pandemic

We investigated what degree of risk of infection with COVID-19 is necessary so that people intend to stay home, even when doing so means losing their salary. We conducted an online survey across Brazil during the initial outbreak, in which 8,345 participants answered a questionnaire designed to identify the maximum tolerated risk (k') necessary for them to disregard social distancing recommendations and guarantee their salaries. Generalized linear mixed models, path analysis structural equation, and conditional interference classification tree were performed to further understand how sociodemographic factors impact k' and to establish a predictive model for the risk behavior of leaving home during the pandemic. We found that, on average, people tolerate 38% risk of infection to leave home and earn a full salary, but this number decreased to 13% when the individual risk perception of becoming ill from severe acute respiratory syndrome coronavirus-2 is considered. Furthermore, participants who have a medium-to-high household income and who are older than 35 years are more likely to be part of the risk-taking group who leave home regardless of the potential COVID-19 infection level; while participants over 45 years old and with good financial health are more likely to be part of the risk-averse group, who stay home at the expense of any salary offered. Our findings add to the political and public debate concerning lockdown strategies by showing that, contrary to supposition, people with low socioeconomic status are not more likely to ignore social distancing recommendations due to personal economic matters.

Long-term Effects of Maternal Separation on Anxiety-Like Behavior and Neuroendocrine Parameters in Adult Balb/c Mice

Introduction: Disruption of maternal care using maternal separation (MS) models has provided significant evidence of the deleterious long-term effects of early life stress. Several preclinical studies investigating MS showed multiple behavioral and biomolecular alterations. However, there is still conflicting results from MS studies, which represents a challenge for reliability and replicability of those findings. Objective: To address that, this study was conducted to investigate whether MS would affect anxiety-like behaviors using a battery of classical tasks, as well as central and peripheral stress-related biomarkers. Methods: Male Balb/c mice were exposed to MS from postnatal day (PND) 2 to 14 for 180-min per day. Two independent cohorts were performed to evaluate both baseline and anxiety-like behavior responses to MS at PND60. We performed composite scores to evaluate MS effects on anxiety and risk assessment phenotypes. Also, we assessed mRNA gene expression in the medial pre-frontal cortex (mPFC) of glucocorticoid and mineralocorticoid receptors (GR and MR) using real-time PCR and peripheral corticosterone levels (CORT) to investigate possible neurobiological correlates to anxiety behaviors. Results: We found increased anxiety-like behavior and decreased risk assessment and exploratory behaviors in MS mice. The animals exposed to MS also presented a decrease in MR mRNA expression and higher levels of CORT compared to controls. Conclusions: Our findings reinforce the body of evidence suggesting that long-term MS induces effects on anxiety and risk assessment phenotypes following the exposure to a standardized MS protocol. Moreover, MS affected the expression of MR mRNA and induced significant changes on CORT response. This data highlights that the reprograming MS effects on HPA axis could be mediate by MR gene expression in mPFC and chronic overactivity of peripheral CORT levels.

Maternal Separation Combined With Limited Bedding Increases Anxiety-Like Behavior and Alters Hypothalamic-Pituitary-Adrenal Axis Function of Male BALB/cJ Mice

Early life stress (ELS) is considered a risk factor for the development of psychiatric conditions, including depression and anxiety disorder. Individuals that live in adverse environments are usually exposed to multiple stressors simultaneously, such as maternal neglect, maltreatment, and limited resources. Nevertheless, most pre-clinical ELS models are designed to explore the impact of these events separately. For this reason, this study aims to investigate the effects of a combined model of ELS on anxiety-like behavior and hypothalamic-pituitary-adrenal (HPA) axis related targets. From PND 2 to PND 15 BALB/cJ mice were exposed simultaneously to maternal separation (MS; 3 h per day) and limited bedding (LB; ELS group) or left undisturbed (CT group). Maternal behavior was recorded in intercalated days, from PND 1 to PND 9. Male offspring were tested for anxiety-like behavior from PND 53 to PND 55 in the open field test (OF), elevated plus-maze (EPM), and light/dark test (LD). After behavioral testing, animals were euthanized, and glucocorticoid receptor (Nr3c1), corticotrophin-releasing hormone (Crh), and its receptor type 1 (Crhr1) gene expression in the hypothalamus were measured. Moreover, plasma corticosterone levels were analyzed. We observed that ELS dams presented altered quality of maternal care, characterized by a decrease in arched-back nursing, and an increase in passive nursing. Stressed dams also showed an increase in the number of exits from the nest when compared to CT dams. Furthermore, ELS animals showed increased anxiety-like behavior in the OF, EPM, and LD. Regarding gene expression, we identified an increase in hypothalamus Crh levels of ELS group when compared to CT animals, while no differences in Nr3c1 and Crhr1 expression were observed. Finally, stressed animals showed decreased levels of plasma corticosterone when compared to the CT group. In conclusion, we observed an alteration in maternal behavior in ELS dams. Later in life, animals exposed to the combined model of ELS showed increased levels of anxiety-like behavior. Moreover, the central and peripheral HPA measures observed could indicate a dysregulation in HPA function provoked by ELS exposure.

Hair cortisol levels and mental health problems in children and adolescents exposed to victimization

Youths who experience multiple forms of victimization are at a heightened risk for psychopathology across the lifespan. The hypothalamic-pituitary-adrenal (HPA) axis is a key target for the investigation of neurobiological changes induced by chronic stress and violence exposure. The measurement of hair cortisol concentration allows the investigation of long-term HPA activity and its association with victimization. The present study investigated the impact of exposure to polyvictimization in Latin-American children and adolescents on hair cortisol levels. We investigated association among cortisol, mental health problems and victimization. The study included 83 youths (mean age 10.84 years-old) from southern Brazil. We assessed self-reported victimization scores (Juvenile Victimization Questionnaire - JVQ-R2), mental health problems (Child Behavior Checklist - CBCL/6-18), and hair cortisol concentrations for the previous 30 days. The results showed an association between exposure to multiple forms of victimization and higher concentrations of hair cortisol; the results also showed that cortisol levels and mental health problems were associated with the severity of polyvictimization. These findings suggest that preadolescent victimization is associated with hyperactivation of HPA axis and with increased risk of mental health issues.

Maternal separation induces long-term oxidative stress alterations and increases anxiety-like behavior of male Balb/cJ mice

Early life stress (ELS) exposure is a well-known risk factor for the development of psychiatric conditions, including anxiety disorder. Preclinical studies show that maternal separation (MS), a classical model of ELS, causes hypothalamic-pituitary-adrenal (HPA) axis alterations, a key contributor to the stress response modulation. Given that HPA axis activation has been shown to induce oxidative stress, it is possible to hypothesize that oxidative stress mediates the relationship between chronic ELS exposure and the development of several disorders. Here, we investigate the effects of MS in the oxidative status [plasma and brain reduced glutathione, catalase and thiobarbituric acid reactive substances (TBARS)], metabolism (glucose, triglycerides and cholesterol) and anxiety-like behaviors in adult Balb/cJ mice. In short, we found that MS increased anxiety-like behaviors in the open field, light/dark test but not in the elevated-plus maze. Animals also presented increased circulating cholesterol, increased TBARS in the plasma and decreased catalase in the hippocampus. Our findings suggest that MS induces long-term alterations in oxidative stress and increased anxiety-like behaviors.

Prediction of attempted suicide in men and women with crack-cocaine use disorder in Brazil

Background

Suicide is a severe health problem, with high rates in individuals with addiction. Considering the lack of studies exploring suicide predictors in this population, we aimed to investigate factors associated with attempted suicide in inpatients diagnosed with cocaine use disorder using two analytical approaches.

Methods

This is a cross-sectional study using a secondary database with 247 men and 442 women hospitalized for cocaine use disorder. Clinical assessment included the Addiction Severity Index, the Childhood Trauma Questionnaire, and the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, totalling 58 variables. Descriptive Poisson regression and predictive Random Forest algorithm were used complementarily to estimate prevalence ratios and to build prediction models, respectively. All analyses were stratified by gender.

Results

The prevalence of attempted suicide was 34% for men and 50% for women. In both genders, depression (PR_M = 1.56, PR_W = 1.27) and hallucinations (PR_M = 1.80, PR_W = 1.39) were factors associated with attempted suicide. Other specific factors were found for men and women, such as childhood trauma, aggression, and drug use severity. The men's predictive model had prediction statistics of AUC = 0.68, Acc. = 0.66, Sens. = 0.82, Spec. = 0.50, PPV = 0.47 and NPV = 0.84. This model identified several variables as important predictors, mainly related to drug use severity. The women's model had higher predictive power (AUC = 0.73 and all other statistics were equal to 0.71) and was parsimonious.

Conclusions

Our findings indicate that attempted suicide is associated with depression, hallucinations and childhood trauma in both genders. Also, it suggests that severity of drug use may be a moderator between predictors and suicide among men, while psychiatric issues shown to be more important for women.

Association of CHRNA5 Gene Variants with Crack Cocaine Addiction

Genome-wide studies provide increasing evidence of association of genetic variants with different behaviors. However, there is a growing need for replication and subsequent characterization of specific findings. In this sense, the CHRNA5 gene has been associated with nicotine (with genome-wide significance), alcohol and cocaine addictions. So far, this gene has not been evaluated in smoked (crack) cocaine. We aimed to analyze the influence of CHRNA5 variants in crack addiction susceptibility and severity. The sample includes 300 crack-addicted patients and 769 non-addicted individuals. The CHRNA5 SNPs evaluated were rs588765, rs16969968, and rs514743. Homozygosity for rs16969968 and rs588765 major alleles was nominally associated with a risk to crack addiction (GG, P = 0.032; CC, P = 0.036, respectively). Haplotype analyses reveal significant associations (rs588765|rs16969968|rs514743 p_{global-corrected} = 7.66 × 10^-5) and suggest a substantial role for rs16969968. These findings corroborate previous reports in cocaine addiction-in line with the expected effects of cocaine in the cholinergic system-and in the opposite direction of significant GWAS findings for nicotine addiction susceptibility. These results are strengthened by the first report of an association of rs588765 with crack addiction and by the haplotype findings. In summary, our study highlights the relevance of the α5 subunit on crack cocaine addiction, replicating previous results relating CHRNA5 with the genetics and pathophysiology of addiction of different drugs.

Vulnerable and resilient cognitive performance related to early life stress: The potential mediating role of dopaminergic receptors in the medial prefrontal cortex of adult mice

RATIONALE

Exposure to early life stress (ELS) is known to have pronounced effects on the prefrontal cortex (PFC). However, not all individuals exposed to ELS manifest the same neurobiological and cognitive phenotypes when adults. Dopamine signaling could be a key factor in understanding the effects of stress on PFC-related cognitive function.

OBJECTIVES

We aimed to investigate the differential effects of ELS on cognitive performance of adult mice and the dopaminergic receptors expression in the PFC.

METHODS

BALB/c males were exposed to the maternal separation (MS) procedure and their cognitive performance on the eight-arm radial maze (8-RAM) were assessed during adulthood. For molecular-level assessments, we performed mRNA expression analyses for dopamine receptors-DRD1, DRD2, DRD3-and Hers1 expression in the medial PFC.

RESULTS

While MS produced an overall impairment on 8-RAM, the stressed animals could be divided in two groups based on their performance: those with impaired cognitive performance (vulnerable to maternal separation, V-MS) and those without any impairment (resilient to maternal separation, R-MS). V-MS animals showed increased DRD1 and DRD2 expression in comparison with other groups. Errors on 8-RAM were also positively correlated with DRD1 and DRD2 mRNA expression.

CONCLUSIONS

Our findings suggest a potential role of the dopaminergic system in the programming mechanisms of cognitive vulnerability and resilience related to ELS.

Percepções de Profissionais sobre Atendimentos em Saúde para Mulheres Usuárias de Crack

Resumo As percepções dos profissionais de saúde que atendem mulheres usuárias de crack podem auxiliar no aprimoramento dos atendimentos. Assim, este estudo objetivou compreender essas percepções. Se trata de um estudo qualitativo, com 33 participantes divididos em três grupos focais submetidos à análise temática. Estabeleceram-se dois eixos centrais: a) usuárias de crack e b) serviços de saúde. Posteriormente, identificaram-se oito temas e seis subtemas. No primeiro eixo destacaram-se: características das usuárias, ausência de rede de apoio, violência, estigma de gênero, prostituição e comorbidades clínicas. No segundo ressaltaram-se as dificuldades na articulação entre os serviços e questões a serem aprimoradas, como: prevenção na atenção básica, motivação dos profissionais, serviços específicos para mulheres, especificidades da gestação e combate ao estigma. A partir dos resultados, foram identificados e discutidos os desafios e as potencialidades que se dão nos atendimentos de mulheres usuárias de crack.

Substance related disorders are associated with impaired valuation of delayed gratification and feedback processing: A multilevel meta-analysis and meta-regression

Across numerous studies, individuals with substance use disorders (SUDs) differed from non-using controls regarding valuation of delayed gratification and feedback processing. However, it remains unclear whether the magnitude of the effect sizes is different across these two cognitive processes and how specific SUDs as well as demographic and clinical moderators influence these effects. In this study we thus performed multilevel linear mixed-effects meta-analyses and meta-regressions to examine the effects of SUDs on the Delay Discounting Task (DD) and on the Iowa Gambling Task (IGT). We found a moderate to large effect for SUD on both, the IGT and DD. While the effect on the DD was generalized to all substance classes, a smaller effect for cannabis-related disorder when compared to other SUDs was found with regard to the IGT. Early onset of substance use and psychiatric comorbidities were associated with stronger effects on the DD. Our findings suggest that feedback processing is more vulnerable to specific substance effects, while valuation of delayed gratification depends more on developmental and clinical factors.

Detecting multiple differentially methylated CpG sites and regions related to dimensional psychopathology in youths

Background

Psychiatric symptomatology during late childhood and early adolescence tends to persist later in life. In the present longitudinal study, we aimed to identify changes in genome-wide DNA methylation patterns that were associated with the emergence of psychopathology in youths from the Brazilian High-Risk Cohort (HRC) for psychiatric disorders. Moreover, for the differentially methylated genes, we verified whether differences in DNA methylation corresponded to differences in mRNA transcript levels by analyzing the gene expression levels in the blood and by correlating the variation of DNA methylation values with the variation of mRNA levels of the same individuals. Finally, we examined whether the variations in DNA methylation and mRNA levels were correlated with psychopathology measurements over time.

Methods

We selected 24 youths from the HRC who presented with an increase in dimensional psychopathology at a 3-year follow-up as measured by the Child Behavior Checklist (CBCL). The DNA methylation and gene expression data were compared in peripheral blood samples (n = 48) obtained from the 24 youths before and after developing psychopathology. We implemented a methodological framework to reduce the effect of chronological age on DNA methylation using an independent population of 140 youths and the effect of puberty using data from the literature.

Results

We identified 663 differentially methylated positions (DMPs) and 90 differentially methylated regions (DMRs) associated with the emergence of psychopathology. We observed that 15 DMPs were mapped to genes that were differentially expressed in the blood; among these, we found a correlation between the DNA methylation and mRNA levels of RB1CC1 and a correlation between the CBCL and mRNA levels of KMT2E. Of the DMRs, three genes were differentially expressed: ASCL2, which is involved in neurogenesis; HLA-E, which is mapped to the MHC loci; and RPS6KB1, the gene expression of which was correlated with an increase in the CBCL between the time points.

Conclusions

We observed that changes in DNA methylation and, consequently, in gene expression in the peripheral blood occurred concurrently with the emergence of dimensional psychopathology in youths. Therefore, epigenomic modulations might be involved in the regulation of an individual’s development of psychopathology.

Cocaine Use Disorder Is Associated With Changes in Th1/Th2/Th17 Cytokines and Lymphocytes Subsets

Background: Cocaine is a psychostimulant drug with high addictive proprieties. Evidence suggests that cocaine use leads to critical changes in the immune system, with significant effects on T, B, and natural killer (NK) cells and influencing peripheral levels of cytokines. The presence of abstinence-related symptoms during detoxification treatment is known to influence the prognosis. Here, our aim was to investigate immune profiles in women with cocaine use disorder (CUD) according to withdrawal symptoms severity.

Methods: Blood samples and clinical data were collected at onset of detoxification treatment of 50 women with CUD. The patients were stratified according to Cocaine Selective Severity Assessment (CSSA) scores in low withdrawal (L-W) and high withdrawal (H-W) categories. In addition, we also included a control group with 19 healthy women as reference to immune parameters. Peripheral blood was collected and lymphocyte subsets were phenotyped by multi-color flow cytometry (B cells, CD4⁺ T, CD8⁺ T, NK cells, and different stages of T-cell differentiation). PBMCs from patients and healthy controls were stimulated in vitro with phytohemagglutinin (1%) for 72 h to assess the production of Th1/Th2/Th17 cytokines.

Results: Following stimulation, lymphocytes from women with CUD produced increased levels of Th1/Th2/Th17 cytokines. However, higher levels of IL-2 and IL-17 were observed only in the L-W group, while higher levels of IL-6 were detected in the H-W group compared to controls. H-W group showed lower percentage of early-differentiated Th cells (CD4⁺CD27⁺CD28⁺), elevated percentage of Th cells (CD3⁺CD4⁺), intermediate-differentiated Th cells (CD4⁺CD27⁻CD28⁺), and B cells (CD3⁻CD19⁺). Both CUD groups showed decreased percentages of naïve T cells (CD3⁺CD4⁺CD45RA⁺ and CD3⁺CD8⁺CD45RA⁺).

Conclusion: Our data demonstrated that CUD can lead to increased production of Th1/Th2/Th17 cytokines and lymphocyte changes.

An fMRI study of inhibitory control and the effects of exposure to violence in Latin-American early adolescents: alterations in frontoparietal activation and performance

We used functional magnetic resonance to investigate the effects of exposure to violence on early adolescent brain function in an inhibitory control task. We investigated the association among scores on self-reported exposure to violence, performance and brain activation. Thirty-seven early adolescents (ages 10-14) from a Latin-American urban region participated in the study. Results showed that recent and chronic exposure to violence was associated with less activation of a network of frontal regions, including the anterior cingulate gyrus and the superior frontal cortex; recent exposure to violence was also associated with less activation of the superior parietal lobe. Results also showed that less activation correlated with more prominent deterioration in the performance in the inhibitory control task (increased latency with time). The findings suggest that early adolescence exposure to violence is associated with differences in activation of a neural network commonly associated with executive function and control. The results underscore the urgency of addressing exposure to violence in adolescence, a period of high susceptibility to the environment, and are discussed in the light of the evidence of the effects of violence on adolescent brain function. Executive function training may be a candidate for targeted cognitive interventions aimed at mitigating these effects.

Association between cognitive performance and SYT1-rs2251214 among women with cocaine use disorder

The SNP rs2251214 of the SYT1 gene was recently associated with externalizing phenotypes, including ADHD and cocaine use disorder (CUD). Here, we investigated whether SYT1-rs2251214 could also be implicated with cognitive performance variations among women with CUD. Results showed that G homozygous (n = 146) have lower cognitive performance in the Stroop, Trail Making and Matrix Reasoning tests compared with A-allele carriers (n = 64), suggesting that rs2251214 may influence the severity of cognitive impairments in CUD.

The association between SYT1-rs2251214 and cocaine use disorder further supports its role in psychiatry

Synaptotagmin-1 is an essential regulator of synaptic vesicle exocytosis, and its encoding gene (SYT1) is a genome and transcriptome-wide association hit in cognitive performance, personality and cocaine use disorder (CUD) studies. Additionally, in candidate gene studies the specific variant rs2251214 has been associated with attention-deficit/hyperactivity disorder (ADHD), antisocial personality disorder and other externalizing phenotypes in adults with ADHD, as well as with response to methylphenidate (MPH) treatment. In this context, we sought to evaluate, in an independent sample, the association of this variant with CUD, a phenotype that shares common biological underpinnings with the previously associated traits. We tested the association between SYT1-rs2251214 and CUD susceptibility and severity (addiction severity index) in a sample composed by 315 patients addicted to smoked cocaine and 769 non-addicted volunteers. SYT1-rs2251214 was significantly associated with susceptibility to CUD, where the G allele presented increased risk for the disorder in the genetic models tested (P = 0.0021, OR = 1.44, allelic; P = 0.0012, OR = 1.48, additive; P = 0.0127, OR = 1.41, dominant). This is the same allele that was associated with increased risk for ADHD and other externalizing behaviors, as well as poor response to MPH treatment in previous studies. These findings suggest that the neurotransmitter exocytosis pathway might play a critical role in the liability for psychiatric disorders, especially externalizing behaviors and CUD.

How Early Life Stress Impact Maternal Care: A Systematic Review of Rodent Studies

Background: Maternal care refers to the behavior performed by the dam to nourish and protect her litter during its early development. Frequent and high-quality performance of such maternal behaviors is critical for the neurodevelopment of the pups. Maternal exposure to stress during early development can impair maternal care and amplify the deleterious effects of poor maternal caregiving and neglect. As such, a thorough understanding of the effects caused by several models of early life stress on maternal care may yield more insights into the relationship between stress and maternal behavior.

Methods: A systematic review was performed to identify and address the effects of early life stress on maternal behavior. The search was conducted using three online databases: PUBMED, Embase, and Web of Science. To provide clear evidence of the impact of stress on maternal care, in every study, the stress group was always compared to a control group. Outcomes were categorized into eight different behaviors: (1) licking/grooming; (2) arched-back nursing; (3) blanket-nursing/passive nursing; (4) nest building; (5) contact with pups; (6) harmful/adverse caregiving; (7) no contact; (8) nest exits. Additionally, the methodological quality of the studies was evaluated.

Results: A total of 12 different early life stress protocols were identified from the 56 studies included in this systematic review. Our data demonstrate that different stress models can promote specific maternal patterns of behavior. Regarding the maternal separation protocol, we observed an overall increase in nursing and licking/grooming behaviors, which are essential for pup development. An increase in the number of nest exits, which represents a fragmentation of maternal care, was observed in the limited bedding protocol, but the total amount of maternal care appears to remain similar between groups.

Conclusions: Each stress protocol has unique characteristics that increase the difficulty of rendering comparisons of maternal behavior. The increase in maternal care observed in the maternal separation protocol may be an attempt to overcompensate for the time off-nest. Fragmented maternal care is a key component of the limited bedding protocol. Moreover, the methodological approaches to evaluate maternal behavior, such as time, duration, and behavior type should be more homogeneous across studies.

Genetic risk for Alzheimer's disease and functional brain connectivity in children and adolescents

Research suggested accumulation of tau proteins might lead to the degeneration of functional networks. Studies investigating the impact of genetic risk for Alzheimer's disease (AD) on early brain connections might shed light on mechanisms leading to AD development later in life. Here, we aim to investigate whether the polygenic risk score for Alzheimer's disease (AD-PRS) influences the connectivity among regions susceptible to tau pathology during childhood and adolescence. Participants were youth, aged 6-14 years, and recruited in Porto Alegre (discovery sample, n = 332) and São Paulo (replication sample, n = 304), Brazil. Subjects underwent genotyping and 6-min resting state funcional magnetic resonance imaging. Connections between the local maxima of tau pathology networks were used as dependent variables. The AD-PRS was associated with the connectivity between the right precuneus and the right superior temporal gyrus (discovery sample: β = 0.180, p_adjusted = 0.036; replication sample: β = 0.202, p = 0.031). This connectivity was also associated with inhibitory control (β = 0.157, p_adjusted = 0.035) and moderated the association between the AD-PRS and both immediate and delayed recall. These findings suggest the AD-PRS may affect brain connectivity in youth, which might impact memory performance and inhibitory control in early life.

Cocaine use disorder in females is associated with altered social decision-making: a study with the prisoner's dilemma and the ultimatum game

BACKGROUND

Chronic cocaine use is associated with cognitive deficits, including poor performance on neuropsychological tasks of memory, executive functions, theory of mind and decision-making. However, the relationship between cocaine use disorder and social decision-making remains unclear. This is particularly relevant given the fact that many cocaine abusers present impairments in social functioning. In this sense, game theory paradigms have been helping to comprehend the behavior of psychiatric patients when they directly engage in social situations, which may better approximate many of their real-life choices.

METHODS

The present study investigated social decision-making in individuals with or without cocaine use disorder, examining their behavior in the Prisoner's Dilemma and in the Ultimatum Game. Thus, 129 females diagnosed with cocaine use disorder and 55 females with no history of substance abuse were recruited and performed both social decision-making tasks. Additional assessments included information about demographics, patterns of substance consumption and executive function performance.

RESULTS

Females with cocaine use disorder opted more often to not defect in the Prisoner's Dilemma, while in the Ultimatum Game they frequently chose to accept the first and unfair offer as responders. These effects were more pronounced within females with long-term history of cocaine use. Associations between cocaine use disorder and altered social decision-making were independent from demographic and executive function variables.

CONCLUSIONS

The influence of cocaine use disorder on social decision-making was detected in both game paradigms, resulting in more cooperative behavior in the Prisoner's Dilemma and higher acceptance rate of unfair offers in the Ultimatum Game. Further studies should focus on investigating these associations to shed light on the putative biopsychosocial factors underlying the observed effects.

Peripheral blood microRNA levels in females with cocaine use disorder

BACKGROUND

There is growing emphasis in the field of psychiatry on the need to identify candidate biomarkers to aid in diagnosis and clinical management of addictive disorders. MicroRNAs (miRNAs) are small nucleotide sequences with the ability to regulate gene expression at the transcriptomic level. However, the role of miRNAs as potential biomarkers for addiction is still underexplored. Based on translational and clinical findings, we compared the expression levels of microRNA-124 (miR-124), microRNA-181 (miR-181), and microRNA-212 (miR-212) between a group of females with cocaine use disorder (CUD; n = 30) and a group of healthy female controls (HC; n = 20).

METHODS

Blood expression levels of miR-124, miR-181, and miR-212 in the HC and CUD group were determined by qPCR, using two miRNAs as endogenous controls (miR-24 and miR-126). Substance use behavior was assessed by self-report using the Addiction Severity Index (ASI-6) and depressive symptoms severity was measured using the Beck Depressive Inventory (BDI-II). Urine screen test was performed to detect cocaine metabolites.

RESULTS

Mir-124 and miR-181 were upregulated in the CUD group (p > 0.01). Furthermore, increased cognitive/affective depression symptoms were identified among a CUD subgroup with the higher miR-181 expression levels (p > 0.05). No significant difference in expression levels was found for miR-212.

CONCLUSIONS

MiR-124 and miR-181 show promise as biomarkers for CUD when assessed in the peripheral blood. Further investigation is needed to elucidate the molecular mechanisms underlying these associations and to validate target genes regulated by these miRNAs.

Hair cortisol concentration, cognitive, behavioral, and motor impairment in multiple sclerosis

Multiple sclerosis (MS) is an autoimmune neurodegenerative disease that is characterized by the demyelinated inflammatory processes that occur within the central nervous system. Hypothalamus-pituitary-adrenal axis (HPA axis) dysfunctions have been associated with the triggering or increase in MS symptoms. We thus aimed at evaluating motor and behavioral functions, planning skills, processing speed, and their relationship with stress through measuring hair cortisol concentration from patients with MS. The sample was composed of 40 volunteers that were clinically diagnosed with MS, along with 33 healthy adults. Evaluations included: Clinical Evaluation Form, Mini-Mental State Exam, Hamilton Depression Rating Scale, Multiple Sclerosis Functional Composite Measure, Expanded Disability Status Scale, Berg Balance Scale, Perceived Stress Scale, Zoo Map task, and a hair sample to analyze cortisol levels in the last 30 days. MS patients showed highly elevated hair cortisol levels in comparison to the control group (p = 0.048). All groups presented some degree of depressive and anxiety symptoms, aside from considerable perceived stress levels. The MS group presented deficits in gait, balance, manual skills and processing speed, and this was particularly so in individuals with moderate impairments when compared to control group (p < 0.001). Individuals with MS spent less time planning on ZooMap1 (p = 0.024) and made more mistakes (p < 0.001). No correlation was found between hair cortisol and the symptoms we assessed. However, depressive symptoms and anxiety were related to perceived stress, and higher hair cortisol suggests a change in levels in the HPA axis in MS. Nevertheless, future studies will be necessary to further understand how basal hair cortisol is related to MS symptoms.

Sex-based differences in multidimensional clinical assessments of early-abstinence crack cocaine users

Crack cocaine use disorder (CUD) has been related to sex differences. This work aimed to compare the severity of drug use and the severity of other negative related outcomes in males and females with CUD. A total of 1344 inpatients (798 males and 546 females) with crack cocaine use disorder (CUD) were evaluated by a detailed multidimensional clinical assessment, including addiction severity and trauma exposure. Linear regression predicted higher drug use severity (β = 0.273, p < 0.001) and more problems in domains related to childcare issues (β = 0.321), criminal involvement (β = 0.108), work-related problems (β = 0.281) and social support impairments (β = 0.142) for females, all with p < 0.001. Alcohol problems were predicted to be higher in males (β = -0.206, P < 0.001). Females had higher rates of other mental disorders, particularly trauma and stress-related disorders (OR: 3.206, CI: 2.22, 4.61). Important sex differences also emerged in trauma history and HIV infection prevalence. CUD has a more severe clinical presentation among females facing early abstinence. Sex differences in the CUD course indicate the need for consideration of sex-specific interventions and research.