Common genetic variation impacts stress response in the brain.

To explain why individuals exposed to identical stressors experience divergent clinical outcomes, we determine how molecular encoding of stress modifies genetic risk for brain disorders. Analysis of post-mortem brain (n=304) revealed 8557 stress-interactive expression quantitative trait loci (eQTLs) that dysregulate expression of 915 eGenes in response to stress, and lie in stress-related transcription factor binding sites. Response to stress is robust across experimental paradigms: up to 50% of stress-interactive eGenes validate in glucocorticoid treated hiPSC-derived neurons (n=39 donors). Stress-interactive eGenes show brain region- and cell type-specificity, and, in post-mortem brain, implicate glial and endothelial mechanisms. Stress dysregulates long-term expression of disorder risk genes in a genotype-dependent manner; stress-interactive transcriptomic imputation uncovered 139 novel genes conferring brain disorder risk only in the context of traumatic stress. Molecular stress-encoding explains individualized responses to traumatic stress; incorporating trauma into genomic studies of brain disorders is likely to improve diagnosis, prognosis, and drug discovery.

Decoding Shared Versus Divergent Transcriptomic Signatures Across Cortico-Amygdala Circuitry in PTSD and Depressive Disorders.

OBJECTIVE: Posttraumatic stress disorder (PTSD) is a debilitating neuropsychiatric disease that is highly comorbid with major depressive disorder (MDD) and bipolar disorder. The overlap in symptoms is hypothesized to stem from partially shared genetics and underlying neurobiological mechanisms. To delineate conservation between transcriptional patterns across PTSD and MDD, the authors examined gene expression in the human cortex and amygdala in these disorders. METHODS: RNA sequencing was performed in the postmortem brain of two prefrontal cortex regions and two amygdala regions from donors diagnosed with PTSD (N=107) or MDD (N=109) as well as from neurotypical donors (N=109). RESULTS: The authors identified a limited number of differentially expressed genes (DEGs) specific to PTSD, with nearly all mapping to cortical versus amygdala regions. PTSD-specific DEGs were enriched in gene sets associated with downregulated immune-related pathways and microglia as well as with subpopulations of GABAergic inhibitory neurons. While a greater number of DEGs associated with MDD were identified, most overlapped with PTSD, and only a few were MDD specific. The authors used weighted gene coexpression network analysis as an orthogonal approach to confirm the observed cellular and molecular associations. CONCLUSIONS: These findings provide supporting evidence for involvement of decreased immune signaling and neuroinflammation in MDD and PTSD pathophysiology, and extend evidence that GABAergic neurons have functional significance in PTSD.

Gene expression in the dorsolateral and ventromedial prefrontal cortices implicates immune-related gene networks in PTSD.

Studies evaluating neuroimaging, genetically predicted gene expression, and pre-clinical genetic models of PTSD, have identified PTSD-related abnormalities in the prefrontal cortex (PFC) of the brain, particularly in dorsolateral and ventromedial PFC (dlPFC and vmPFC). In this study, RNA sequencing was used to examine gene expression in the dlPFC and vmPFC using tissue from the VA National PTSD Brain Bank in donors with histories of PTSD with or without depression (dlPFC n = 38, vmPFC n = 35), depression cases without PTSD (n = 32), and psychopathology-free controls (dlPFC n = 24, vmPFC n = 20). Analyses compared PTSD cases to controls. Follow-up analyses contrasted depression cases to controls. Twenty-one genes were differentially expressed in PTSD after strict multiple testing correction. PTSD-associated genes with roles in learning and memory (FOS, NR4A1), immune regulation (CFH, KPNA1) and myelination (MBP, MOBP, ERMN) were identified. PTSD-associated genes partially overlapped depression-associated genes. Co-expression network analyses identified PTSD-associated networks enriched for immune-related genes across the two brain regions. However, the immune-related genes and association patterns were distinct. The immune gene IL1B was significantly associated with PTSD in candidate-gene analysis and was an upstream regulator of PTSD-associated genes in both regions. There was evidence of replication of dlPFC associations in an independent cohort from a recent study, and a strong correlation between the dlPFC PTSD effect sizes for significant genes in the two studies (r = 0.66, p < 2.2 × 10-16). In conclusion, this study identified several novel PTSD-associated genes and brain region specific PTSD-associated immune-related networks.

Transcriptomic organization of the human brain in post-traumatic stress disorder.

Despite extensive study of the neurobiological correlates of post-traumatic stress disorder (PTSD), little is known about its molecular determinants. Here, differential gene expression and network analyses of four prefrontal cortex subregions from postmortem tissue of people with PTSD demonstrate extensive remodeling of the transcriptomic landscape. A highly connected downregulated set of interneuron transcripts is present in the most significant gene network associated with PTSD. Integration of this dataset with genotype data from the largest PTSD genome-wide association study identified the interneuron synaptic gene ELFN1 as conferring significant genetic liability for PTSD. We also identified marked transcriptomic sexual dimorphism that could contribute to higher rates of PTSD in women. Comparison with a matched major depressive disorder cohort revealed significant divergence between the molecular profiles of individuals with PTSD and major depressive disorder despite their high comorbidity. Our analysis provides convergent systems-level evidence of genomic networks within the prefrontal cortex that contribute to the pathophysiology of PTSD in humans.

Psychiatric Prodrome in Anti-NMDAR-Associated Encephalopathy: Clinical and Pathophysiologic Considerations.

OBJECTIVE: To present a review of the literature on the clinical presentation and pathophysiology of anti-N-methyl-d-aspartate receptor encephalopathy (ANMDARE) with attention to both the more commonly recognized psychotic symptom prodrome and the less well-understood depressive symptom prodrome. DATA SOURCES: The search for clinical neuropsychiatric phenomena and proposed mechanisms involved in ANMDARE pathophysiology was conducted in PubMed. English-language articles published up to September 2019 were identified using a combination of the following search terms: N-methyl-d-aspartate, anti-NMDA receptor encephalitis, schizophrenia, psychosis, depression, major depressive disorder, bipolar I disorder, bipolar II disorder, anxiety, and posttraumatic stress disorder. STUDY SELECTION: From 150 articles identified from the initial search, the 73 most relevant clinical studies, reviews, and case reports related to the study objectives were included. DATA EXTRACTION: Sources were individually analyzed by the 3 authors for the most clinically relevant information. RESULTS: The pathophysiology and mechanisms involved in anti-NMDA receptor antibody delivery to the brain are incompletely characterized, but antibody binding appears to involve the GluN1 subunit in most cases. Psychotic symptoms are the most commonly recognized components of prodromal psychiatric illness in ANMDARE, which may lead to an initial diagnosis of schizophrenia. In addition to psychotic symptoms, there are reports of depressive symptoms occurring before the emergence of, co-occurring with, or instead of psychotic symptoms in ANMDARE. CONCLUSIONS: In addition to the better-known psychotic prodrome, depressive symptomatology can occur in ANMDARE patients. ANMDARE should be considered in patients with initial presentation of either psychotic or atypical depressive illnesses. Early recognition of these psychiatric prodromal states as antecedents to ANMDARE could lead to improved diagnosis and better management of this potentially life-threatening autoimmune disorder.

Utility of oxcarbazepine in the treatment of childhood and adolescent psychiatric symptoms.

The primary aims of this study were to determine if oxcarbazepine is a safely tolerated option for treatment of psychiatric symptoms in children and whether its use facilitates dose modification of other psychotropic medications. A retrospective chart review was completed using data extracted from the electronic medical record of a large outpatient child psychiatry clinic. A total of 507 of 740 children prescribed oxcarbazepine for psychiatric indications for 3 months or more had adequate data to assess clinical responses and medication outcomes. Most patients prescribed oxcarbazepine experienced clinically significant control of irritability/anger, mood stabilization, aggressive outbursts, impulsivity, or anxiety, with over 80% achieving at least maintenance symptom control. In all, 51% and 25% fully discontinued second- or third-generation antipsychotic or antidepressant medication, respectively, after starting oxcarbazepine; 8% discontinued oxcarbazepine for nonresponse, while 9% stopped oxcarbazepine because of emergent side effects. In patients fully discontinuing or reducing the second- or third-generation antipsychotic dose by 50% or more, improvements in body mass index were observed. Oxcarbazepine may prove to be an appropriate alternative to antipsychotic and antidepressant medications for treating psychiatric symptoms in children and adolescents. In particular, it may be a more metabolically neutral psychotropic medication.

Frontal Lobe Circuitry in Posttraumatic Stress Disorder.

Symptoms of posttraumatic stress disorder include hyperarousal, avoidance of trauma-related stimuli, re-experiencing of trauma, and mood changes. This review focuses on the frontal cortical areas that form crucial links in circuitry pertinent to posttraumatic stress disorder symptomatology: (1) the conditioned fear extinction circuit, (2) the salience circuit, and (3) the mood circuit. These frontal areas include the ventromedial prefrontal cortex (conditioned fear extinction), the dorsal anterior cingulate and insular cortices (salience), and the lateral orbitofrontal and subgenual cingulate cortices (mood). Frontal lobe structural abnormalities in posttraumatic stress disorder, including volumetric reductions in the cingulate cortices, impact all three circuits. Functional analyses of frontal cortices in posttraumatic stress disorder show abnormal activation in all three according to task demand and emotional valence. Network analyses reveal altered amygdalo-frontal connectivity and failure to suppress the default mode network during cognitive engagement. Spine shape alterations also have been detected in the medial orbito-frontal cortex in posttraumatic stress disorder postmortem brains, suggesting reduced synaptic plasticity. Importantly, frontal lobe abnormalities in posttraumatic stress disorder extend beyond emotion-related circuits to include the lateral prefrontal cortices that mediate executive functions. In conclusion, widespread frontal lobe dysfunction in posttraumatic stress disorder provides a neurobiologic basis for the core symptomatology of the disorder, as well as for executive function impairment.

BA11 FKBP5 expression levels correlate with dendritic spine density in postmortem PTSD and controls.

Genetic variants of the immunophilin FKBP5 have been implicated in susceptibility to post-traumatic stress disorder (PTSD) and other stress-related disorders. We examined the relationship between mushroom, stubby, thin and filopodial spine densities measured with Golgi staining and FKBP5 gene expression in the medial orbitofrontal cortex (BA11) in individuals diagnosed with PTSD and normal controls (n = 8/8). ANCOVA revealed PTSD cases had a significantly elevated density of stubby spines (29%, P < 0.037) and a trend for a reduction in mushroom spine density (25%, p < 0.082). Levels of FKBP5 mRNA were marginally elevated in the PTSD cases (z = 1.94, p = 0.053) and levels correlated inversely with mushroom (Spearman's rho = -0.83, p < 0.001) and overall spine density (rho = -0.75, p < 0.002) and directly with stubby spine density (rho = 0.55, p < 0.027). These data suggest that FKBP5 may participate in a cellular pathway modulating neuronal spine density changes in the brain, and that this pathway may be dysregulated in PTSD.

An examination of the broader effects of warzone experiences on returning Iraq/Afghanistan veterans' psychiatric health.

The objective of the present research was to test the hypotheses that: (1) Iraq/Afghanistan war veterans experience a wide range of psychiatric symptomatology (e.g., obsessive-compulsive symptoms, hypochondriasis, somatization); and (2) general psychiatric symptomatology among Iraq/Afghanistan war veterans is associated with their warzone experiences. To achieve this objective, Iraq/Afghanistan war veterans (N=155) completed a screening questionnaire that assessed a wide range of psychiatric symptoms along with a measure of warzone experiences. As expected, returning veterans reported significant elevations across a wide range of clinical scales. Approximately three-fourths screened positive on at least one clinical subscale, and a one-third screened positive on five or more. In addition, nearly all of these conditions were associated with veterans' warzone experiences (average r=0.36); however, this association was much stronger among veterans with posttraumatic stress disorder (PTSD) (average r=0.33) than among veterans without PTSD (average r=0.15). We also observed that approximately 18% of the variance in total psychiatric symptomatology was attributable to warzone experiences above and beyond the effects of childhood trauma and demographic factors. Taken together, these findings suggest that returning veterans experience a broad array of psychiatric symptoms that are strongly associated with their warzone experiences.

Do child abuse and maternal care interact to predict military sexual trauma?

OBJECTIVE: The present research tested the hypothesis that maternal care moderates the relationship between childhood sexual abuse and subsequent military sexual trauma (MST). METHOD: Measures of childhood sexual abuse, maternal care, and MST were administered to 197 Iraq and Afghanistan war veterans. RESULTS: After accounting for gender, age, and the main effects of maternal care and childhood sexual abuse, the maternal care x childhood sexual abuse interaction was a significant predictor of MST (odds ratio = .28, ß = -1.26, 95% confidence intervals of .10, .80). As hypothesized, rates of MST were higher among veterans who reported childhood sexual abuse and low levels of maternal care (43%) compared with veterans who reported childhood sexual abuse and high levels of maternal care (11%). CONCLUSION: These findings suggest that high levels of maternal care may act as a protective factor against future revictimization among military service members. These findings have the potential to inform both prevention and intervention efforts.

Effect of the 5-HTTLPR polymorphism on posttraumatic stress disorder, depression, anxiety, and quality of life among Iraq and Afghanistan veterans.

BACKGROUND AND OBJECTIVES: Posttraumatic stress disorder (PTSD), depression, anxiety, and stress are significant problems among returning veterans and are associated with reduced quality of life. DESIGN: A correlational design was used to examine the impact of a polymorphism (5-HTTLPR) in the serotonin transporter promoter gene on post-deployment adjustment among returning veterans. METHODS: A total of 186 returning Iraq and Afghanistan veterans were genotyped for the 5-HTTLPR polymorphism. Symptoms of PTSD, depression, general stress, and anxiety were assessed along with quality of life. RESULTS: After controlling for combat exposure, age, sex of the participant, and race, 5-HTTLPR had a significant multivariate effect on post-deployment adjustment, such that S' carriers reported more post-deployment adjustment problems and worse quality of life than veterans homozygous for the L' allele. This effect was larger when the analyses were restricted to veterans of European ancestry. CONCLUSIONS: Our findings suggest that veterans who carry the S' allele of the 5-HTTLPR polymorphism may be at increased risk for adjustment problems and reduced quality of life following deployments to war zones.

Neuropathology and animal models of autism: genetic and environmental factors.

Autism is a heterogeneous behaviorally defined neurodevelopmental disorder. It is defined by the presence of marked social deficits, specific language abnormalities, and stereotyped repetitive patterns of behavior. Because of the variability in the behavioral phenotype of the disorder among patients, the term autism spectrum disorder has been established. In the first part of this review, we provide an overview of neuropathological findings from studies of autism postmortem brains and identify the cerebellum as one of the key brain regions that can play a role in the autism phenotype. We review research findings that indicate possible links between the environment and autism including the role of mercury and immune-related factors. Because both genes and environment can alter the structure of the developing brain in different ways, it is not surprising that there is heterogeneity in the behavioral and neuropathological phenotypes of autism spectrum disorders. Finally, we describe animal models of autism that occur following insertion of different autism-related genes and exposure to environmental factors, highlighting those models which exhibit both autism-like behavior and neuropathology.

Neuropsychological sequelae of PTSD and TBI following war deployment among OEF/OIF veterans.

Posttraumatic stress disorder (PTSD) and mild traumatic brain injury (mTBI) are highly prevalent among Veterans of the conflicts in Iraq and Afghanistan. These conditions are associated with common and unique neuropsychological and neuroanatomical changes. This review synthesizes neuropsychological and neuroimaging studies for both of these disorders and studies examining their co-occurrence. Recommendations for future research, including use of combined neuropsychological and advanced neuroimaging techniques to study these disorders alone and in concert, are presented. It is clear from the dearth of literature that addiitonal studies are required to examine and understand the impact of specific factors on neurocognitive outcome. Of particular relevance are temporal relationships between PTSD and mTBI, risk and resilience factors associated with both disorders and their co-occurrence, and mTBI-specific factors such as time since injury and severity of injury, utilizing comprehensive, yet targeted cognitive tasks.

The functional connectivity of the human caudate: an application of meta-analytic connectivity modeling with behavioral filtering.

Meta-analysis based techniques are emerging as powerful, robust tools for developing models of connectivity in functional neuroimaging. Here, we apply meta-analytic connectivity modeling to the human caudate to 1) develop a model of functional connectivity, 2) determine if meta-analytic methods are sufficiently sensitive to detect behavioral domain specificity within region-specific functional connectivity networks, and 3) compare meta-analytic driven segmentation to structural connectivity parcellation using diffusion tensor imaging. Results demonstrate strong coherence between meta-analytic and data-driven methods. Specifically, we found that behavioral filtering resulted in cognition and emotion related structures and networks primarily localized to the head of the caudate nucleus, while perceptual and action specific regions localized to the body of the caudate, consistent with early models of nonhuman primate histological studies and postmortem studies in humans. Diffusion tensor imaging (DTI) revealed support for meta-analytic connectivity modeling's (MACM) utility in identifying both direct and indirect connectivity. Our results provide further validation of meta-analytic connectivity modeling, while also highlighting an additional potential, namely the extraction of behavioral domain specific functional connectivity.

High psychopathic trait females exhibit reduced startle potentiation and increased p3 amplitude.

While there has been steady progress in identifying psychophysiological traits associated with psychopathy, most of the existing research has been carried out using incarcerated male participants, and data that include females are particularly rare. This study examined both affective startle blink modulation and P3 amplitude in a sample of female undergraduates grouped by scores on the Psychopathic Personality Inventory-Revised (PPI-R). Those scoring high for psychopathic traits lacked startle blink potentiation and demonstrated larger P3 amplitudes during auditory and visual oddball tasks. These data support the generalizability of deficient startle potentiation to non-incarcerated females with psychopathic traits, and add to a growing body of literature suggesting that psychopathic traits are associated with distinctive information-processing characteristics as indexed by P3 amplitude.

PSAPP mice exhibit regionally selective reductions in gliosis and plaque deposition in response to S100B ablation.

BACKGROUND: Numerous studies have reported that increased expression of S100B, an intracellular Ca2+ receptor protein and secreted neuropeptide, exacerbates Alzheimer's disease (AD) pathology. However, the ability of S100B inhibitors to prevent/reverse AD histopathology remains controversial. This study examines the effect of S100B ablation on in vivo plaque load, gliosis and dystrophic neurons. METHODS: Because S100B-specific inhibitors are not available, genetic ablation was used to inhibit S100B function in the PSAPP AD mouse model. The PSAPP/S100B-/- line was generated by crossing PSAPP double transgenic males with S100B-/- females and maintained as PSAPP/S100B+/- crosses. Congo red staining was used to quantify plaque load, plaque number and plaque size in 6 month old PSAPP and PSAPP/S100B-/- littermates. The microglial marker Iba1 and astrocytic marker glial fibrillary acidic protein (GFAP) were used to quantify gliosis. Dystrophic neurons were detected with the phospho-tau antibody AT8. S100B immunohistochemistry was used to assess the spatial distribution of S100B in the PSAPP line. RESULTS: PSAPP/S100B-/- mice exhibited a regionally selective decrease in cortical but not hippocampal plaque load when compared to PSAPP littermates. This regionally selective reduction in plaque load was accompanied by decreases in plaque number, GFAP-positive astrocytes, Iba1-positive microglia and phospho-tau positive dystrophic neurons. These effects were not attributable to regional variability in the distribution of S100B. Hippocampal and cortical S100B immunoreactivity in PSAPP mice was associated with plaques and co-localized with astrocytes and microglia. CONCLUSIONS: Collectively, these data support S100B inhibition as a novel strategy for reducing cortical plaque load, gliosis and neuronal dysfunction in AD and suggest that both extracellular as well as intracellular S100B contribute to AD histopathology.

Centella asiatica extract selectively decreases amyloid beta levels in hippocampus of Alzheimer's disease animal model.

PSAPP mice expressing the 'Swedish' amyloid precursor protein and the M146L presenilin 1 mutations are a well-characterized model for spontaneous amyloid beta plaque formation. Centella asiatica has a long history of use in India as a memory enhancing drug in Ayurvedic literature. The study investigated whether Centella asiatica extract (CaE) can alter the amyloid pathology in PSAPP mice by administering CaE (2.5 or 5.0 g/kg/day) starting at 2 months of age prior to the onset of detectable amyloid deposition and continued for either 2 months or 8 months. A significant decrease in amyloid beta 1-40 and 1-42 was detectable by ELISA following an 8 month treatment with 2.5 mg/kg of CaE. A reduction in Congo Red stained fibrillar amyloid plaques was detected with the 5.0 mg/kg CaE dose and long-term treatment regimen. It was also confirmed that CaE functions as an antioxidant in vitro, scavenging free radicals, reducing lipid peroxidation and protecting against DNA damage. The data indicate that CaE can impact the amyloid cascade altering amyloid beta pathology in the brains of PSAPP mice and modulating components of the oxidative stress response that has been implicated in the neurodegenerative changes that occur with Alzheimer's disease.