RESUMO
Despite experiencing a significant trauma, only a subset of World Trade Center (WTC) rescue and recovery workers developed posttraumatic stress disorder (PTSD). Identification of biomarkers is critical to the development of targeted interventions for treating disaster responders and potentially preventing the development of PTSD in this population. Analysis of gene expression from these individuals can help in identifying biomarkers of PTSD. We established a well-phenotyped sample of 371 WTC responders, recruited from a longitudinal WTC responder cohort using stratified random sampling, by obtaining blood, self-reported and clinical interview data. Using bulk RNA-sequencing from whole blood, we examined the association between gene expression and WTC-related PTSD symptom severity on (i) highest lifetime Clinician-Administered PTSD Scale (CAPS) score, (ii) past-month CAPS score, and (iii) PTSD symptom dimensions using a 5-factor model of re-experiencing, avoidance, emotional numbing, dysphoric arousal and anxious arousal symptoms. We corrected for sex, age, genotype-derived principal components and surrogate variables. Finally, we performed a meta-analysis with existing PTSD studies (total N = 1016), using case/control status as the predictor and correcting for these variables. We identified 66 genes significantly associated with total highest lifetime CAPS score (FDR-corrected p < 0.05), and 31 genes associated with total past-month CAPS score. Our more granular analyses of PTSD symptom dimensions identified additional genes that did not reach statistical significance in our analyses with total CAPS scores. In particular, we identified 82 genes significantly associated with lifetime anxious arousal symptoms. Several genes significantly associated with multiple PTSD symptom dimensions and total lifetime CAPS score (SERPINA1, RPS6KA1, and STAT3) have been previously associated with PTSD. Geneset enrichment of these findings has identified pathways significant in metabolism, immune signaling, other psychiatric disorders, neurological signaling, and cellular structure. Our meta-analysis revealed 10 genes that reached genome-wide significance, all of which were downregulated in cases compared to controls (CIRBP, TMSB10, FCGRT, CLIC1, RPS6KB2, HNRNPUL1, ALDOA, NACA, ZNF429 and COPE). Additionally, cellular deconvolution highlighted an enrichment in CD4 T cells and eosinophils in responders with PTSD compared to controls. The distinction in significant genes between total lifetime CAPS score and the anxious arousal symptom dimension of PTSD highlights a potential biological difference in the mechanism underlying the heterogeneity of the PTSD phenotype. Future studies should be clear about methods used to analyze PTSD status, as phenotypes based on PTSD symptom dimensions may yield different gene sets than combined CAPS score analysis. Potential biomarkers implicated from our meta-analysis may help improve therapeutic target development for PTSD.
Assuntos
Ataques Terroristas de 11 de Setembro , Transtornos de Estresse Pós-Traumáticos , Ansiedade , Canais de Cloreto , Expressão Gênica , Humanos , Proteínas de Ligação a RNA , Autorrelato , Ataques Terroristas de 11 de Setembro/psicologia , Transtornos de Estresse Pós-Traumáticos/diagnósticoRESUMO
DNA methylation patterns at specific cytosine-phosphate-guanine (CpG) sites predictably change with age and can be used to derive "epigenetic age", an indicator of biological age, as opposed to merely chronological age. A relatively new estimator, called "DNAm GrimAge", is notable for its superior predictive ability in older populations regarding numerous age-related metrics like time-to-death, time-to-coronary heart disease, and time-to-cancer. PTSD is associated with premature mortality and frequently has comorbid physical illnesses suggestive of accelerated biological aging. This is the first study to assess DNAm GrimAge in PTSD patients. We investigated the acceleration of GrimAge relative to chronological age, denoted "AgeAccelGrim" in combat trauma-exposed male veterans with and without PTSD using cross-sectional and longitudinal data from two independent well-characterized veteran cohorts. In both cohorts, AgeAccelGrim was significantly higher in the PTSD group compared to the control group (N = 162, 1.26 vs -0.57, p = 0.001 and N = 53, 0.93 vs -1.60 Years, p = 0.008), suggesting accelerated biological aging in both cohorts with PTSD. In 3-year follow-up study of individuals initially diagnosed with PTSD (N = 26), changes in PTSD symptom severity were correlated with AgeAccelGrim changes (r = 0.39, p = 0.049). In addition, the loss of CD28 cell surface markers on CD8 + T cells, an indicator of T-cell senescence/exhaustion that is associated with biological aging, was positively correlated with AgeAccelGrim, suggesting an immunological contribution to the accelerated biological aging. Overall, our findings delineate cellular correlates of biological aging in combat-related PTSD, which may help explain the increased medical morbidity and mortality seen in this disease.
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Metilação de DNA , Transtornos de Estresse Pós-Traumáticos , Idoso , Envelhecimento/genética , Estudos Transversais , Metilação de DNA/genética , Epigênese Genética , Epigenômica , Seguimentos , Humanos , Masculino , Transtornos de Estresse Pós-Traumáticos/genéticaRESUMO
Post-traumatic stress disorder (PTSD) is a heterogeneous condition evidenced by the absence of objective physiological measurements applicable to all who meet the criteria for the disorder as well as divergent responses to treatments. This study capitalized on biological diversity observed within the PTSD group observed following epigenome-wide analysis of a well-characterized Discovery cohort (N = 166) consisting of 83 male combat exposed veterans with PTSD, and 83 combat veterans without PTSD in order to identify patterns that might distinguish subtypes. Computational analysis of DNA methylation (DNAm) profiles identified two PTSD biotypes within the PTSD+ group, G1 and G2, associated with 34 clinical features that are associated with PTSD and PTSD comorbidities. The G2 biotype was associated with an increased PTSD risk and had higher polygenic risk scores and a greater methylation compared to the G1 biotype and healthy controls. The findings were validated at a 3-year follow-up (N = 59) of the same individuals as well as in two independent, veteran cohorts (N = 54 and N = 38), and an active duty cohort (N = 133). In some cases, for example Dopamine-PKA-CREB and GABA-PKC-CREB signaling pathways, the biotypes were oppositely dysregulated, suggesting that the biotypes were not simply a function of a dimensional relationship with symptom severity, but may represent distinct biological risk profiles underpinning PTSD. The identification of two novel distinct epigenetic biotypes for PTSD may have future utility in understanding biological and clinical heterogeneity in PTSD and potential applications in risk assessment for active duty military personnel under non-clinician-administered settings, and improvement of PTSD diagnostic markers.
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Militares , Transtornos de Estresse Pós-Traumáticos , Veteranos , Epigênese Genética/genética , Epigenoma , Humanos , Masculino , Transtornos de Estresse Pós-Traumáticos/genéticaRESUMO
Post-traumatic stress disorder (PTSD) impacts many veterans and active duty soldiers, but diagnosis can be problematic due to biases in self-disclosure of symptoms, stigma within military populations, and limitations identifying those at risk. Prior studies suggest that PTSD may be a systemic illness, affecting not just the brain, but the entire body. Therefore, disease signals likely span multiple biological domains, including genes, proteins, cells, tissues, and organism-level physiological changes. Identification of these signals could aid in diagnostics, treatment decision-making, and risk evaluation. In the search for PTSD diagnostic biomarkers, we ascertained over one million molecular, cellular, physiological, and clinical features from three cohorts of male veterans. In a discovery cohort of 83 warzone-related PTSD cases and 82 warzone-exposed controls, we identified a set of 343 candidate biomarkers. These candidate biomarkers were selected from an integrated approach using (1) data-driven methods, including Support Vector Machine with Recursive Feature Elimination and other standard or published methodologies, and (2) hypothesis-driven approaches, using previous genetic studies for polygenic risk, or other PTSD-related literature. After reassessment of ~30% of these participants, we refined this set of markers from 343 to 28, based on their performance and ability to track changes in phenotype over time. The final diagnostic panel of 28 features was validated in an independent cohort (26 cases, 26 controls) with good performance (AUC = 0.80, 81% accuracy, 85% sensitivity, and 77% specificity). The identification and validation of this diverse diagnostic panel represents a powerful and novel approach to improve accuracy and reduce bias in diagnosing combat-related PTSD.
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Militares , Transtornos de Estresse Pós-Traumáticos , Veteranos , Biomarcadores , Encéfalo , Humanos , Masculino , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/genéticaRESUMO
Although glucocorticoid resistance contributes to increased inflammation, individuals with posttraumatic stress disorder (PTSD) exhibit increased glucocorticoid receptor (GR) sensitivity along with increased inflammation. It is not clear how inflammation coexists with a hyperresponsive hypothalamic-pituitary-adrenal (HPA) axis. To understand this better, we developed and analyzed an integrated mathematical model for the HPA axis and the immune system. We performed mathematical simulations for a dexamethasone (DEX) suppression test and IC50-dexamethasone for cytokine suppression by varying model parameters. The model analysis suggests that increasing the steepness of the dose-response curve for GR activity may reduce anti-inflammatory effects of GRs at the ambient glucocorticoid levels, thereby increasing proinflammatory response. The adaptive response of proinflammatory cytokine-mediated stimulatory effects on the HPA axis is reduced due to dominance of the GR-mediated negative feedback on the HPA axis. To verify these hypotheses, we analyzed the clinical data on neuroendocrine variables and cytokines obtained from war-zone veterans with and without PTSD. We observed significant group differences for cortisol and ACTH suppression tests, proinflammatory cytokines TNFα and IL6, high-sensitivity C-reactive protein, promoter methylation of GR gene, and IC50-DEX for lysozyme suppression. Causal inference modeling revealed significant associations between cortisol suppression and post-DEX cortisol decline, promoter methylation of human GR gene exon 1F (NR3C1-1F), IC50-DEX, and proinflammatory cytokines. We noted significant mediation effects of NR3C1-1F promoter methylation on inflammatory cytokines through changes in GR sensitivity. Our findings suggest that increased GR sensitivity may contribute to increased inflammation; therefore, interventions to restore GR sensitivity may normalize inflammation in PTSD.
Assuntos
Citocinas/imunologia , Glucocorticoides/imunologia , Receptores de Glucocorticoides/imunologia , Transtornos de Estresse Pós-Traumáticos/imunologia , Hormônio Adrenocorticotrópico/imunologia , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Campanha Afegã de 2001- , Proteína C-Reativa/imunologia , Estudos de Casos e Controles , Ritmo Circadiano , Metilação de DNA , Dexametasona , Glucocorticoides/metabolismo , Humanos , Hidrocortisona/imunologia , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/imunologia , Sistema Hipotálamo-Hipofisário/metabolismo , Inflamação , Concentração Inibidora 50 , Interleucina-6/imunologia , Guerra do Iraque 2003-2011 , Masculino , Modelos Teóricos , Testes de Função Adreno-Hipofisária , Sistema Hipófise-Suprarrenal/imunologia , Sistema Hipófise-Suprarrenal/metabolismo , Regiões Promotoras Genéticas , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Transtornos de Estresse Pós-Traumáticos/metabolismo , Fator de Necrose Tumoral alfa/imunologia , VeteranosRESUMO
Posttraumatic stress disorder (PTSD) is associated with neuroendocrine alterations and metabolic abnormalities; however, how metabolism is affected by neuroendocrine disturbances is unclear. The data from combat-exposed veterans with PTSD show increased glycolysis to lactate flux, reduced TCA cycle flux, impaired amino acid and lipid metabolism, insulin resistance, inflammation, and hypersensitive hypothalamic-pituitary-adrenal (HPA) axis. To analyze whether the co-occurrence of multiple metabolic abnormalities is independent or arises from an underlying regulatory defect, we employed a systems biological approach using an integrated mathematical model and multiomic analysis. The models for hepatic metabolism, HPA axis, inflammation, and regulatory signaling were integrated to perform metabolic control analysis (MCA) with respect to the observations from our clinical data. We combined the metabolomics, neuroendocrine, clinical laboratory, and cytokine data from combat-exposed veterans with and without PTSD to characterize the differences in regulatory effects. MCA revealed mechanistic association of the HPA axis and inflammation with metabolic dysfunction consistent with PTSD. This was supported by the data using correlational and causal analysis that revealed significant associations between cortisol suppression, high-sensitivity C-reactive protein, homeostatic model assessment of insulin resistance, γ-glutamyltransferase, hypoxanthine, and several metabolites. Causal mediation analysis indicates that the effects of enhanced glucocorticoid receptor sensitivity (GRS) on glycolytic pathway, gluconeogenic and branched-chain amino acids, triglycerides, and hepatic function are jointly mediated by inflammation, insulin resistance, oxidative stress, and energy deficit. Our analysis suggests that the interventions to normalize GRS and inflammation may help to manage features of metabolic dysfunction in PTSD.
Assuntos
Doenças Metabólicas/metabolismo , Receptores de Glucocorticoides/metabolismo , Transtornos de Estresse Pós-Traumáticos/metabolismo , Adulto , Citocinas/metabolismo , Glicólise , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Fígado/metabolismo , Masculino , Metabolômica , Pessoa de Meia-Idade , Modelos Teóricos , Sistemas Neurossecretores/metabolismo , Biologia de Sistemas , Veteranos , Adulto JovemRESUMO
Trait domains of the five-factor model are not orthogonal, and two metatraits have often been estimated from their covariation. Here, we focus on the stability metatrait, which reflects shared variance in conscientiousness, agreeableness, and (inversely) neuroticism. It has been hypothesized that stability manifests, in part, because of individual differences in central serotonergic functioning. We explored this possibility in a community sample (N = 441) using a multiverse analysis of (a) multi-informant five-factor-model traits and (b) stability as a predictor of individual differences in central serotonergic functioning. Differences in serotonergic functioning were assessed by indexing change in serum prolactin concentration following intravenous infusion of citalopram, a selective serotonin reuptake inhibitor. Results were mixed, showing that trait neuroticism, agreeableness, and conscientiousness, as well as the stability metatrait, were significantly associated with prolactin response but that these findings were contingent on a number of modeling decisions. Specifically, these effects were nonlinear, emerging most strongly for participants with the highest levels (or lowest, for neuroticism) of the component traits.
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Citalopram/administração & dosagem , Determinação da Personalidade , Prolactina/fisiologia , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Serotonina/fisiologia , Adulto , Feminino , Humanos , Individualidade , Infusões Intravenosas , Análise de Classes Latentes , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Dinâmica não Linear , PersonalidadeRESUMO
BACKGROUND: Trait impulsivity is thought to play a key role in predicting behaviors on the externalizing spectrum, such as drug and alcohol use and aggression. Research suggests that impulsivity may not be a unitary construct, but rather multidimensional in nature with dimensions varying across self-report assessments and laboratory behavioral tasks. Few studies with large samples have included a range of impulsivity-related measures and assessed several externalizing behaviors to clarify the predictive validity of these assessments on important life outcomes. METHODS: Community adults (N = 1295) between the ages of 30 and 54 completed a multidimensional assessment of impulsivity-related traits (including 54 self-report scales of personality traits implicated in impulsive behaviors, and four behavioral tasks purporting to assess a construct similar to impulsivity) and reported on five externalizing behavioral outcomes (i.e. drug, alcohol, and cigarette use, and physical and verbal aggression). We ran an exploratory factor analysis on the trait scales, and then a structural equation model predicting the externalizing behaviors from the three higher-order personality factors (i.e. Disinhibition v. Constraint/Conscientiousness, Neuroticism/Negative Emotionality, and Extraversion/Positive Emotionality) and the four behavioral tasks. RESULTS: Relations between the self-report factors and behavioral tasks were small or nonexistent. Associations between the self-report factors and the externalizing outcomes were generally medium to large, but relationships between the behavioral tasks and externalizing outcomes were either nonexistent or small. CONCLUSIONS: These results partially replicate and extend recent meta-analytic findings reported by Sharma et al. (2014) to further clarify the predictive validity of impulsivity-related trait scales and laboratory behavioral tasks on externalizing behaviors.
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Agressão/fisiologia , Consumo de Bebidas Alcoólicas/fisiopatologia , Sintomas Comportamentais/diagnóstico , Comportamento Impulsivo/fisiologia , Inventário de Personalidade/normas , Personalidade/fisiologia , Autorrelato/normas , Fumar/fisiopatologia , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Adulto , Sintomas Comportamentais/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Relacionados ao Uso de Substâncias/fisiopatologiaRESUMO
Excessive alcohol use is extremely prevalent in the United States, particularly among trauma-exposed individuals. While several studies have examined genetic influences on alcohol use and related problems, this has not been studied in the context of trauma-exposed populations. We report results from a genome-wide association study of alcohol consumption and associated problems as measured by the alcohol use disorders identification test (AUDIT) in a trauma-exposed cohort. Results indicate a genome-wide significant association between total AUDIT score and rs1433375 [N = 1036, P = 2.61 × 10-8 (dominant model), P = 7.76 × 10-8 (additive model)], an intergenic single-nucleotide polymorphism located 323 kb upstream of the sodium channel and clathrin linker 1 (SCLT1) at 4q28. rs1433375 was also significant in a meta-analysis of two similar, but independent, cohorts (N = 1394, P = 0.0004), the Marine Resiliency Study and Systems Biology PTSD Biomarkers Consortium. Functional analysis indicated that rs1433375 was associated with SCLT1 gene expression and cortical-cerebellar functional connectivity measured via resting state functional magnetic resonance imaging. Together, findings suggest a role for sodium channel regulation and cerebellar functioning in alcohol use behavior. Identifying mechanisms underlying risk for problematic alcohol use in trauma-exposed populations is critical for future treatment and prevention efforts.
Assuntos
Alcoolismo/complicações , Alcoolismo/genética , Estudo de Associação Genômica Ampla/métodos , Canais de Sódio/genética , Transtornos de Estresse Pós-Traumáticos/complicações , Adolescente , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Alcoolismo/fisiopatologia , Encéfalo/fisiopatologia , Estudos de Coortes , Feminino , Georgia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Adulto JovemRESUMO
INTRODUCTION: Several lines of evidence indicate that increased inflammation is associated with Post-Traumatic Stress Disorder (PTSD). We have previously reported that peripheral inflammatory markers are significantly higher in combat-exposed veterans with than without PTSD. This study was designed to replicate these findings in a new study cohort using the same population and recruitment strategies. METHODS: Sixty-one male war veterans (31 PTSD and 30 control subjects) were included in this replication study. Levels of Interleukin-6, Tumor Necrosis Factor-alpha, Gamma interferon, and high-sensitivity C-reactive protein were quantified in blood samples. A standardized "total pro-inflammatory score" was calculated to limit the number of statistical comparisons. The Clinician Administered PTSD Scale (CAPS) rating scale was used to assess PTSD symptom severity. RESULTS: PTSD subjects had significantly higher total pro-inflammatory scores compared to non-PTSD subjects in unadjusted analysis (Cohen's d=0.75, p=0.005) as well as after adjusting for potentially confounding effects of age, BMI, smoking, and potentially interfering medications and somatic co-morbidities (p=0.023). There were no significant correlations between inflammatory markers and severity of symptoms within the PTSD group. CONCLUSIONS: We replicated, in a new sample, our previous finding of increased inflammatory markers in combat-exposed PTSD subjects compared to combat-exposed non-PTSD controls. These findings strongly add to the growing literature suggesting that immune activation may be an important aspect of PTSD pathophysiology, although not directly correlated with current PTSD symptom levels in the PTSD group.
Assuntos
Inflamação/patologia , Transtornos de Estresse Pós-Traumáticos/patologia , Adulto , Estudos de Coortes , Distúrbios de Guerra/sangue , Citocinas/sangue , Manual Diagnóstico e Estatístico de Transtornos Mentais , Humanos , Inflamação/sangue , Masculino , Escalas de Graduação Psiquiátrica , Fatores de Risco , Transtornos de Estresse Pós-Traumáticos/sangue , Transtornos de Estresse Pós-Traumáticos/psicologia , VeteranosRESUMO
Varying associations are reported between Five-Factor Model (FFM) personality traits and cardiovascular disease risk. Here, we further examine dispositional correlates of cardiometabolic risk within a hierarchical model of personality that proposes higher-order traits of Stability (shared variance of Agreeableness, Conscientiousness, inverse Neuroticism) and Plasticity (Extraversion, Openness), and we test hypothesized mediation via biological and behavioral factors. In an observational study of 856 community volunteers aged 30-54 years (46% male, 86% Caucasian), latent variable FFM traits (using multiple-informant reports) and aggregated cardiometabolic risk (indicators: insulin resistance, dyslipidemia, blood pressure, adiposity) were estimated using confirmatory factor analysis (CFA). The cardiometabolic factor was regressed on each personality factor or higher-order trait. Cross-sectional indirect effects via systemic inflammation, cardiac autonomic control, and physical activity were tested. CFA models confirmed the Stability "meta-trait," but not Plasticity. Lower Stability was associated with heightened cardiometabolic risk. This association was accounted for by inflammation, autonomic function, and physical activity. Among FFM traits, only Openness was associated with risk over and above Stability, and, unlike Stability, this relationship was unexplained by the intervening variables. A Stability meta-trait covaries with midlife cardiometabolic risk, and this association is accounted for by three candidate biological and behavioral factors.
Assuntos
Sistema Nervoso Autônomo/fisiologia , Doenças Cardiovasculares/fisiopatologia , Exercício Físico/fisiologia , Inflamação/fisiopatologia , Personalidade/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , RiscoRESUMO
BACKGROUND: Chronic inflammation may be involved in combat-related post-traumatic stress disorder (PTSD) and may help explain comorbid physical diseases. However, the extent to which combat exposure per se, depression, or early life trauma, all of which are associated with combat PTSD, may confound the relationship between PTSD and inflammation is unclear. METHODS: We quantified interleukin (IL)-6, IL-1ß, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and C-reactive protein (CRP) in 51 combat-exposed males with PTSD and 51 combat-exposed males without PTSD, and assessed PTSD and depression severity as well as history of early life trauma. To decrease the possibility of Type I errors, we summed standardized scores of IL-1ß, IL-6, TNFα, IFNγ and CRP into a total "pro-inflammatory score". PTSD symptom severity was assessed with the Clinician Administered PTSD Scale (CAPS) rating scale. RESULTS: Subjects with PTSD had significantly higher pro-inflammatory scores compared to combat-exposed subjects without PTSD (p=0.006), and even after controlling for early life trauma, depression diagnosis and severity, body mass index, ethnicity, education, asthma/allergies, time since combat and the use of possibly confounding medications (p=0.002). Within the PTSD group, the pro-inflammatory score was not significantly correlated with depressive symptom severity, CAPS total score, or with the number of early life traumas. CONCLUSIONS: Combat-related PTSD in males is associated with higher levels of pro-inflammatory cytokines, even after accounting for depression and early life trauma. These results, from one of the largest studies of inflammatory cytokines in PTSD to date, suggest that immune activation may be a core element of PTSD pathophysiology more so than a signature of combat exposure alone.
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Distúrbios de Guerra/sangue , Citocinas/sangue , Transtorno Depressivo/sangue , Transtornos de Estresse Pós-Traumáticos/sangue , Estresse Psicológico/sangue , Adulto , Proteína C-Reativa/metabolismo , Distúrbios de Guerra/complicações , Transtorno Depressivo/complicações , Humanos , Inflamação/sangue , Inflamação/complicações , Interleucina-1beta/sangue , Interleucina-6/sangue , Acontecimentos que Mudam a Vida , Masculino , Militares , Transtornos de Estresse Pós-Traumáticos/complicações , Estresse Psicológico/complicações , Fator de Necrose Tumoral alfa/sangue , Adulto JovemRESUMO
Circulating cell-free mitochondrial DNA (ccf-mtDNA) is a biomarker of cellular injury or cellular stress and is a potential novel biomarker of psychological stress and of various brain, somatic, and psychiatric disorders. No studies have yet analyzed ccf-mtDNA levels in post-traumatic stress disorder (PTSD), despite evidence of mitochondrial dysfunction in this condition. In the current study, we compared plasma ccf-mtDNA levels in combat trauma-exposed male veterans with PTSD (n = 111) with those who did not develop PTSD (n = 121) and also investigated the relationship between ccf mt-DNA levels and glucocorticoid sensitivity. In unadjusted analyses, ccf-mtDNA levels did not differ significantly between the PTSD and non-PTSD groups (t = 1.312, p = 0.191, Cohen's d = 0.172). In a sensitivity analysis excluding participants with diabetes and those using antidepressant medication and controlling for age, the PTSD group had lower ccf-mtDNA levels than did the non-PTSD group (F(1, 179) = 5.971, p = 0.016, partial η2 = 0.033). Across the entire sample, ccf-mtDNA levels were negatively correlated with post-dexamethasone adrenocorticotropic hormone (ACTH) decline (r = -0.171, p = 0.020) and cortisol decline (r = -0.149, p = 0.034) (viz., greater ACTH and cortisol suppression was associated with lower ccf-mtDNA levels) both with and without controlling for age, antidepressant status and diabetes status. Ccf-mtDNA levels were also significantly positively associated with IC50-DEX (the concentration of dexamethasone at which 50% of lysozyme activity is inhibited), a measure of lymphocyte glucocorticoid sensitivity, after controlling for age, antidepressant status, and diabetes status (ß = 0.142, p = 0.038), suggesting that increased lymphocyte glucocorticoid sensitivity is associated with lower ccf-mtDNA levels. Although no overall group differences were found in unadjusted analyses, excluding subjects with diabetes and those taking antidepressants, which may affect ccf-mtDNA levels, as well as controlling for age, revealed decreased ccf-mtDNA levels in PTSD. In both adjusted and unadjusted analyses, low ccf-mtDNA levels were associated with relatively increased glucocorticoid sensitivity, often reported in PTSD, suggesting a link between mitochondrial and glucocorticoid-related abnormalities in PTSD.
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Ácidos Nucleicos Livres , Diabetes Mellitus , Transtornos de Estresse Pós-Traumáticos , Veteranos , Humanos , Masculino , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/genética , Glucocorticoides , Hidrocortisona , DNA Mitocondrial/genética , Hormônio Adrenocorticotrópico , Antidepressivos , Biomarcadores , Dexametasona/farmacologiaRESUMO
Physical activity enhances cognitive performance, yet individual variability in its effectiveness limits its widespread therapeutic application. Genetic differences might be one source of this variation. For example, carriers of the methionine-specifying (Met) allele of the brain-derived neurotrophic factor (BDNF) Val66Met polymorphism have reduced secretion of BDNF and poorer memory, yet physical activity increases BDNF levels. To determine whether the BDNF polymorphism moderated an association of physical activity with cognitive functioning among 1,032 midlife volunteers (mean age = 44.59 years), we evaluated participants' performance on a battery of tests assessing memory, learning, and executive processes, and evaluated their physical activity with the Paffenbarger Physical Activity Questionnaire. BDNF genotype interacted robustly with physical activity to affect working memory, but not other areas of cognitive functioning. In particular, greater levels of physical activity offset a deleterious effect of the Met allele on working memory performance. These findings suggest that physical activity can modulate domain-specific genetic (BDNF) effects on cognition.
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Fator Neurotrófico Derivado do Encéfalo/genética , Memória de Curto Prazo/fisiologia , Atividade Motora/fisiologia , Polimorfismo Genético/genética , Adulto , Feminino , Humanos , Masculino , Metionina/genética , Testes Neuropsicológicos/estatística & dados numéricos , Inquéritos e Questionários , Valina/genéticaRESUMO
BACKGROUND: An association between impulsivity and smoking has been consistently reported in the literature, but few studies have examined how distinct dimensions of impulsivity may relate differentially to smoking initiation versus persistent smoking. The aim of the current study was to examine the relationship between self-report and behavioral measures of impulsivity and smoking status in college students. METHODS: Participants (N = 243) completed a self-report history of tobacco use, 2 self-report measures of impulsivity (the Barratt Impulsiveness Scale and Zuckerman Sensation-Seeking Scale), and 2 behavioral measures (the Delay Discounting Task and Iowa Gambling Task). All participants were classified as never-smokers, triers, or smokers based on their smoking history, and between-group differences on the 4 measures were examined. RESULTS: On the self-report measures, all 3 groups differed on sensation seeking, with the never-smokers reporting the lowest levels and the smokers reporting the highest. Furthermore, the smokers reported significantly higher disinhibitory impulsivity than the triers and never-smokers. The groups did not differ on the behavioral measures. CONCLUSIONS: These results indicate that distinct dimensions of impulsivity characterize different smoking phenotypes. In particular, sensation seeking is associated with the initiation of smoking, whereas disinhibitory impulsivity is associated with the transition to more persistent and regular use of cigarettes.
Assuntos
Comportamento Impulsivo/psicologia , Fumar/epidemiologia , Fumar/psicologia , Estudantes/estatística & dados numéricos , Universidades , Adulto , Tomada de Decisões , Feminino , Humanos , Comportamento Impulsivo/epidemiologia , Masculino , Inventário de Personalidade , Assunção de Riscos , AutorrelatoRESUMO
Importance: To date, no psychopharmacologic treatment has been found to be uniformly effective in veterans with posttraumatic stress disorder (PTSD); novel targets and approaches are needed to treat this disabling disorder. Objective: To examine whether treatment with the glucocorticoid receptor antagonist mifepristone yields a signal for clinical efficacy in male veterans with PTSD. Design, Setting, and Participants: This phase 2a, double-blind, parallel-group randomized clinical trial was conducted from November 19, 2012 (accrual started), through November 16, 2016 (final follow-up), within the US Department of Veterans Affairs. Participants were male veterans with chronic PTSD and a screening Clinician-Administered PTSD Scale score of 50 or higher. A total of 181 veterans consented to participation. Statistical analysis was conducted between August 2014 and May 2017. Interventions: Participants were randomized in a 1:1 ratio to mifepristone (600 mg) or matched placebo taken orally for 7 days. Main Outcomes and Measures: The clinical outcome was whether a veteran achieved a clinical response status (a reduction of ≥30% of total Clinician-Administered PTSD Scale score from baseline) at 4- and 12-week follow-up. On the basis of a binary statistical selection rule, a difference in the proportion of treatment vs control group responders of 15% would be a clinically relevant difference. Self-report measures of PTSD and associated symptoms were also obtained. Neuroendocrine outcomes and plasma levels of mifepristone were measured. Safety was assessed throughout the study. The primary analysis was based on a multiple imputation technique to address missing outcome data; thus, some participant numbers may not appear as whole numbers. Results: A total of 81 veterans were enrolled and randomized. Excluding 1 participant randomized in error, 80 were included in the modified intention-to-treat analysis (41 randomized to mifepristone and 39 to placebo). The mean (SD) age was 43.1 (13.7) years. A total of 15.6 (38.1%) in the mifepristone group and 12.1 (31.1%) in the placebo group were clinical responders at 4 weeks in the analysis using the multiple imputation technique. The group difference in the proportion of clinical responders (7.0%) was less than the predefined margin of 15% indicating signal for clinical efficacy. In an exploratory analysis, the difference in response to mifepristone vs placebo in the subgroup with no lifetime history of traumatic brain injury (TBI) (7.0 [50.0%] vs 3.0 [27.3%]; difference, 22.7%) exceeded the efficacy margin at 4 weeks and was sustained at 12 weeks. In contrast, in veterans with PTSD and lifetime TBI, the response rate to mifepristone was lower than placebo at 12 weeks (7.4 [27.4%] vs 13.5 [48.3%]; difference, -20.9%). Conclusions and Relevance: This study did not detect a signal for efficacy for mifepristone at 600 mg/d for 1 week in male veterans with chronic PTSD. Thus, this study does not support a phase 3 trial in this population. Future studies of mifepristone for the treatment of PTSD may be of interest in those without a history of TBI or in samples with a low base rate of lifetime head trauma. Trial Registration: ClinicalTrials.gov Identifier: NCT01946685.
Assuntos
Lesões Encefálicas Traumáticas , Transtornos de Estresse Pós-Traumáticos , Veteranos , Estados Unidos , Humanos , Masculino , Adulto , Feminino , Mifepristona/efeitos adversos , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Cegueira , GalopamilRESUMO
Post-traumatic stress disorder (PTSD) is a multisystem syndrome. Integration of systems-level multi-modal datasets can provide a molecular understanding of PTSD. Proteomic, metabolomic, and epigenomic assays are conducted on blood samples of two cohorts of well-characterized PTSD cases and controls: 340 veterans and 180 active-duty soldiers. All participants had been deployed to Iraq and/or Afghanistan and exposed to military-service-related criterion A trauma. Molecular signatures are identified from a discovery cohort of 218 veterans (109/109 PTSD+/-). Identified molecular signatures are tested in 122 separate veterans (62/60 PTSD+/-) and in 180 active-duty soldiers (PTSD+/-). Molecular profiles are computationally integrated with upstream regulators (genetic/methylation/microRNAs) and functional units (mRNAs/proteins/metabolites). Reproducible molecular features of PTSD are identified, including activated inflammation, oxidative stress, metabolic dysregulation, and impaired angiogenesis. These processes may play a role in psychiatric and physical comorbidities, including impaired repair/wound healing mechanisms and cardiovascular, metabolic, and psychiatric diseases.
Assuntos
Militares , Transtornos de Estresse Pós-Traumáticos , Veteranos , Humanos , Militares/psicologia , Veteranos/psicologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/genética , Transtornos de Estresse Pós-Traumáticos/psicologia , Proteômica , InflamaçãoRESUMO
Functional neuroimaging often generates large amounts of data on regions of interest. Such data can be addressed effectively with a widely-used statistical technique based on measurement theory that has not yet been applied to neuroimaging. Confirmatory factor analysis is a convenient hypothesis-driven modeling environment that can be used to conduct formal statistical tests comparing alternative hypotheses regarding the elements of putative neuronal networks. In such models, measures of each activated region of interest are treated as indicators of an underlying latent construct that represents the contemporaneous activation of the elements in the network. As such, confirmatory factor analysis focuses analyses on the activation of hypothesized networks as a whole, improves statistical power by modeling measurement error, and provides a theory-based approach to data reduction with a robust statistical basis. This approach is illustrated using data on seven regions of interest in a hypothesized mesocorticostriatal reward system in a sample of 262 adult volunteers assessed during a card-guessing reward task. A latent construct reflecting contemporaneous activation of the reward system was found to be significantly associated with a latent construct measuring impulsivity, particularly in males.
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Mapeamento Encefálico/métodos , Análise Fatorial , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Modelos Teóricos , Adolescente , Adulto , Encéfalo/fisiologia , Feminino , Humanos , Masculino , Adulto JovemRESUMO
BACKGROUND: Hostility is a multidimensional construct related to cardiovascular (CV) disease risk. Daily hostile mood and social interactions may precipitate stress-related CV responses in hostile individuals. PURPOSE: Determine whether trait cognitive hostility best predicts daily hostile mood and social interactions relative to other trait hostility factors and explore the temporal links between these daily measures. METHODS: One hundred seventy-one participants completed assessments of four trait hostility scales. Participants completed an electronic diary across 3 days, assessing current hostile mood and social interaction quality. RESULTS: Multiple regression analyses revealed both affective and cognitive hostility to be significant predictors of daily hostile mood, and cognitive hostility alone to predict daily social strain. Additional analyses revealed previous social strain to predict elevated subsequent hostile mood. CONCLUSIONS: Episodes of social strain may give rise to elevated hostile mood. Trait cognitive hostility may be an important factor in predicting daily social strain.