The relationship between prenatal psychological stress and placental abruption in Japan, The Japan Environment and Children's Study (JECS).

BACKGROUND: Prenatal psychological stress may increase the risk of placental abruption (PA). This study aimed to clarify the effects of psychological distress during pregnancy and exposure to stressful life events in the year before or during pregnancy on the occurrence of PA in Japanese women. METHODS: Using a nationwide prospective birth cohort study, we obtained data from 103,099 women between January 2011 and March 2014. Information on exposure to 14 stressful life events and psychological distress (Kessler 6 scale) was collected using a self-administered questionnaire during pregnancy. Clinical diagnoses of PA were obtained from medical records. A total of 80,799 women with singleton births were analyzed using logistic regression models that adjusted for possible confounders. RESULTS: PA was diagnosed in 335 (0.4%) women. There was no significant difference in the Kessler 6 score during pregnancy between the PA group and non-PA group. Exposure to the death of a child in the year before or during pregnancy was significantly associated with PA in multigravid women (adjusted odds ratio [aOR] 3.57; 95% confidence interval [CI] 1.50-8.34). A spouse's loss of employment was significantly associated with PA in parous women (aOR 3.25; 95% CI 1.40-7.56). CONCLUSIONS: This study identified the possible effects of exposure to the death of a child on PA occurrence that adjusted for important confounding factors.

Secondary traumatic stress increases expression of proteins implicated in peripheral and central sensitization of trigeminal neurons.

The pathology of migraine, a common neurological disease, involves sensitization and activation of trigeminal nociceptive neurons to promote hyperalgesia and allodynia during an attack. Migraineurs often exhibit characteristics of a hyperexcitable or hypervigilant nervous system. One of the primary reported risk factors for development of a hyperexcitable trigeminal system is chronic, unmanaged stress and anxiety. While primary traumatic stress is a commonly cited risk factor for many pain conditions, exposure to secondary traumatic stress early in life is also thought to be a contributing risk factor. The goal of this study was to investigate cellular changes within the spinal trigeminal nucleus and trigeminal ganglion mediated by secondary traumatic stress. Male Sprague Dawley rats (sender) were subjected to forced swim testing (primary traumatic stress) and were then housed in close visual, olfactory, and auditory proximity to the breeding male and female rats, pregnant female rats, or female rats and their nursing offspring (all receivers). In response to secondary stress, levels of calcitonin gene-related peptide, active forms of the mitogen activated protein kinases ERK, JNK, and p38, and astrocyte expression of glial fibrillary acidic protein were significantly elevated in the spinal trigeminal nucleus in day 45 offspring when compared to naïve offspring. In addition, increased nuclear expression of ERK and p38 was observed in trigeminal ganglion neurons. Our results demonstrate that secondary traumatic stress promotes cellular events associated with prolonged trigeminal sensitization in the offspring, and provides a mechanism of how early life stress may function as a risk factor for migraine.

The ventromedial prefrontal cortex in a model of traumatic stress: fear inhibition or contextual processing?

The ventromedial prefrontal cortex (vmPFC) has consistently appeared altered in post-traumatic stress disorder (PTSD). Although the vmPFC is thought to support the extinction of learned fear responses, several findings support a broader role for this structure in the regulation of fear. To further characterize the relationship between vmPFC dysfunction and responses to traumatic stress, we examined the effects of pretraining vmPFC lesions on trauma reactivity and enhanced fear learning in a rodent model of PTSD. In Experiment 1, lesions did not produce differences in shock reactivity during an acute traumatic episode, nor did they alter the strength of the traumatic memory. However, when lesioned animals were subsequently given a single mild aversive stimulus in a novel context, they showed a blunting of the enhanced fear response to this context seen in traumatized animals. In order to address this counterintuitive finding, Experiment 2 assessed whether lesions also attenuated fear responses to discrete tone cues. Enhanced fear for discrete cues following trauma was preserved in lesioned animals, indicating that the deficit observed in Experiment 1 is limited to contextual stimuli. These findings further support the notion that the vmPFC contributes to the regulation of fear through its influence on context learning and contrasts the prevailing view that the vmPFC directly inhibits fear.

Potential of Environmental Enrichment to Prevent Transgenerational Effects of Paternal Trauma.

Adverse experiences in early life are risk factors for the development of behavioral and physiological symptoms that can lead to psychiatric and cognitive disorders later in life. Some of these symptoms can be transmitted to the offspring, in some cases by non-genomic mechanisms involving germ cells. Using a mouse model of unpredictable maternal separation and maternal stress, we show that postnatal trauma alters coping behaviors in adverse conditions in exposed males when adult and in their adult male progeny. The behavioral changes are accompanied by increased glucocorticoid receptor (GR) expression and decreased DNA methylation of the GR promoter in the hippocampus. DNA methylation is also decreased in sperm cells of exposed males when adult. Transgenerational transmission of behavioral symptoms is prevented by paternal environmental enrichment, an effect associated with the reversal of alterations in GR gene expression and DNA methylation in the hippocampus of the male offspring. These findings highlight the influence of both negative and positive environmental factors on behavior across generations and the plasticity of the epigenome across life.

D-Cycloserine acts via increasing the GluN1 protein expressions in the frontal cortex and decreases the avoidance and risk assessment behaviors in a rat traumatic stress model.

D-cycloserine (DCS), an FDA approved anti-tuberculosis drug has extensively been studied for its cognitive enhancer effects in psychiatric disorders. DCS may enhance the effects of fear extinction trainings in animals during exposure therapy and hence we investigated the effects of DCS on distinct behavioral parameters in a predator odor stress model and tested the optimal duration for repeated daily administrations of the agent. Cat fur odor blocks were used to produce stress and avoidance and risk assessment behavioral parameters were used where DCS or saline were used as treatments in adjunct to extinction trainings. We observed that DCS facilitated extinction training by providing further extinction of avoidance responses, risk assessment behaviors and increased the contact with the cue in a setting where DCS was administered before extinction trainings for 3 days without producing a significant tolerance. In amygdala and hippocampus, GluN1 protein expressions decreased 72h after the fear conditioning in the traumatic stress group suggesting a possible down-regulation of NMDARs. We observed that extinction learning increased GluN1 proteins both in the amygdaloid complex and the dorsal hippocampus of the rats receiving extinction training or extinction training with DCS. Our findings also indicate that DCS with extinction training increased GluN1 protein levels in the frontal cortex. We may suggest that action of DCS relies on enhancement of the consolidation of fear extinction in the frontal cortex.

POTS following traumatic stress: interacting central and intracardiac neural control?

Cardiovascular autonomic dysfunction is one of the most overlooked complications in patients with diabetes. We report the case of a 19-year-old woman with a 4-year history of diabetes referred due to palpitations and light-headedness following traumatic stress. Rise of heart rate and blood pressure during tilt table testing indicated hyperadrenergic postural orthstatic tachycardia syndrome (POTS). Elevated blood pressure variability, an indirect parameter of increased sympathetic activity, remained almost stable during orthostatic stress. Short-term treatment with ivabradine in combination with psychosocial support alleviated POTS-related symptoms. Our findings suggest that traumatic stress in patients with type 1 diabetes mellitus might translate into disturbed neural heart rate control due to a central, ephemeral alteration in autonomic balance.

Pathological brain plasticity and cognition in the offspring of males subjected to postnatal traumatic stress.

Traumatic stress in early-life increases the risk for cognitive and neuropsychiatric disorders later in life. Such early stress can also impact the progeny even if not directly exposed, likely through epigenetic mechanisms. Here, we report in mice that the offspring of males subjected to postnatal traumatic stress have decreased gene expression in molecular pathways necessary for neuronal signaling, and altered synaptic plasticity when adult. Long-term potentiation is abolished and long-term depression is enhanced in the hippocampus, and these defects are associated with impaired long-term memory in both the exposed fathers and their offspring. The brain-specific gamma isoform of protein kinase C (Prkcc) is one of the affected signaling components in the hippocampus. Its expression is reduced in the offspring, and DNA methylation at its promoter is altered both in the hippocampus of the offspring and the sperm of fathers. These results suggest that postnatal traumatic stress in males can affect brain plasticity and cognitive functions in the adult progeny, possibly through epigenetic alterations in the male germline.

Cyclooxygenase-2 blockade inhibits accumulation and function of myeloid-derived suppressor cells and restores T cell response after traumatic stress.

Myeloid-derived suppressor cells (MDSCs) play a crucial role in T cell dysfunction, which is related to poor outcome in patients with severe trauma. Cyclooxygenase-2 (Cox-2) contributes to immune disorder in trauma and infection via production of prostaglandin E2. However, the role of Cox-2 in the accumulation and function of MDSCs after traumatic stress has not been fully elucidated. In the present study, we treated murine trauma model with NS398, a selective Cox-2 inhibitor. Then the percentages of CD11b+/Gr-1+ cells, proliferation and apoptosis of CD4+ T cells were determined. Arginase activity and arginase-1 (Arg-1) protein expression of splenic CD11b+/Gr-1+ cells, and delayed-type hypersensitivity (DTH) response were analyzed. The results showed that Cox-2 blockade significantly decreased the percentages of CD11b+/Gr-1+ cells in the spleen and bone marrow 48 and 72 h after traumatic stress. NS398 inhibited arginase activity and down-regulated the Arg-1 expression of splenic CD11b+/Gr-1+ cells. Moreover, NS398 could promote proliferation and inhibit apoptosis of CD4+ T cells. It also restored DTH response of traumatic mice. Taken together, our data revealed that Cox-2 might play a pivotal role in the accumulation and function of MDSC after traumatic stress.

Epigenetic regulation of RAC1 induces synaptic remodeling in stress disorders and depression.

Depression induces structural and functional synaptic plasticity in brain reward circuits, although the mechanisms promoting these changes and their relevance to behavioral outcomes are unknown. Transcriptional profiling of the nucleus accumbens (NAc) for Rho GTPase-related genes, which are known regulators of synaptic structure, revealed a sustained reduction in RAS-related C3 botulinum toxin substrate 1 (Rac1) expression after chronic social defeat stress. This was associated with a repressive chromatin state surrounding the proximal promoter of Rac1. Inhibition of class 1 histone deacetylases (HDACs) with MS-275 rescued both the decrease in Rac1 transcription after social defeat stress and depression-related behavior, such as social avoidance. We found a similar repressive chromatin state surrounding the RAC1 promoter in the NAc of subjects with depression, which corresponded with reduced RAC1 transcription. Viral-mediated reduction of Rac1 expression or inhibition of Rac1 activity in the NAc increases social defeat-induced social avoidance and anhedonia in mice. Chronic social defeat stress induces the formation of stubby excitatory spines through a Rac1-dependent mechanism involving the redistribution of synaptic cofilin, an actin-severing protein downstream of Rac1. Overexpression of constitutively active Rac1 in the NAc of mice after chronic social defeat stress reverses depression-related behaviors and prunes stubby spines. Taken together, our data identify epigenetic regulation of RAC1 in the NAc as a disease mechanism in depression and reveal a functional role for Rac1 in rodents in regulating stress-related behaviors.

Sex differences in the combined effect of chronic stress with impaired vascular endothelium functioning and the development of early atherosclerosis: the Cardiovascular Risk in Young Finns study.

BACKGROUND: The syndrome of vital exhaustion (VE), characterized by fatigue and irritability, may contribute to an increased risk of atherosclerosis. The aim of the study was to explore sex differences in the interactions of VE with endothelial dysfunction and VE with reduced carotid elasticity, the important contributors to the development of early atherosclerosis, on preclinical atherosclerosis. METHODS: The participants were 1002 women and 719 men aged 24-39 examined in the Cardiovascular Risk in Young Finns study. Vital exhaustion was measured using the Maastricht Questionnaire. Preclinical atherosclerosis was assessed by carotid intima-media thickness (IMT), endothelial function was measured by brachial flow-mediated dilatation (FMD), and arterial elasticity by carotid artery compliance (CAC) using ultrasound techniques. RESULTS: We found a significant CAC x VE interaction for IMT only for the men. Our results imply that high VE level significantly related to high IMT levels among the men with low CAC, but not among the women with low CAC or among the women or men with high CAC. No significant FMD x VE interactions for IMT for the women or men were found. CONCLUSIONS: High VE may exert an effect on IMT for men with impaired arterial elasticity. The results suggest that high vitally exhausted men with reduced arterial elasticity are at increased risk of atherosclerosis in early life and imply men's decreased stress coping in relation to stressful psychological coronary risk factors.

Getting closer to affective disorders: the role of CRH receptor systems.

Depressive disorders are a leading cause of morbidity and mortality worldwide. Current antidepressant drugs targeting monoamine neurotransmitter systems have a delayed onset of action, and fewer than 50% of the patients attain complete remission after therapy with a single antidepressant. A large body of preclinical and clinical evidence points to a key role of the corticotropin-releasing hormone (CRH) receptor 1 subtype (CRHR1) in mediating CRH-elicited effects in anxiety, depressive disorders and stress-associated pathologies. Genetic modification of CRHR1 function in mice by the use of conventional and conditional knockout strategies enables further analysis of specific elements in the CRH circuitry. The recent characterisation of several selective small-molecule CRHR1 antagonists offers new possibilities for the treatment of anxiety and depression.