Post‐traumatic stress disorder (PTSD) is a psychiatric disorder of high prevalence and major socioeconomic impact. Patients suffering from PTSD typically present intrusion and avoidance symptoms and ...alterations in arousal, mood and cognition that last for more than 1 month. Animal models are an indispensable tool to investigate underlying pathophysiological pathways and, in particular, the complex interplay of neuroendocrine, genetic and environmental factors that may be responsible for PTSD induction. Since the 1960s, numerous stress paradigms in rodents have been developed, based largely on Seligman's seminal formulation of ‘learned helplessness’ in canines. Rodent stress models make use of physiological or psychological stressors such as foot shock, underwater trauma, social defeat, early life stress or predator‐based stress. Apart from the brief exposure to an acute stressor, chronic stress models combining a succession of different stressors for a period of several weeks have also been developed. Chronic stress models in rats and mice may elicit characteristic PTSD‐like symptoms alongside, more broadly, depressive‐like behaviours. In this review, the major existing rodent models of PTSD are reviewed in terms of validity, advantages and limitations; moreover, significant results and implications for future research—such as the role of FKBP5, a mediator of the glucocorticoid stress response and promising target for therapeutic interventions—are discussed.
Endogenous oxytocin has been associated with different aspects of social cognition in healthy subjects and patients with schizophrenia. In this pilot study, we investigated the relationship between ...plasma oxytocin and oxytocin level changes induced by empathy-eliciting, attachment-related movie scenes with correlates of cognitive and emotional empathy in patients and healthy controls. The Multifaceted Empathy Test (MET) and the Interpersonal Reactivity Index (IRI) were administered to patients with schizophrenia (N = 35, 12 females) and healthy controls (N = 35, 12 females) to estimate dimensions of cognitive and emotional empathy. Peripheral basal oxytocin concentrations and oxytocin responses to movie-based emotional stimuli were assessed using radioimmunoassay with sample extraction. In patients, induced oxytocin level changes were inversely correlated with MET cognitive empathy regarding negative emotional states. Controlling for non-social cognition and age revealed a significant negative association between basal oxytocin levels and MET cognitive empathy for positive emotions. In healthy subjects, oxytocin reactivity was inversely correlated with the IRI subscale "fantasy". Oxytocin was not related to any measure of emotional empathy. A hyper-reactive oxytocin system might be linked to impaired cognitive empathy as a part of a dysfunctional regulative circuit of attachment-related emotions and interpersonal stressors or threats by attribution of meaning. Healthy adults with a disposition to identify with fictional characters showed lower oxytocin reactivity, possibly indicating familiarity with movie-based stimuli. The oxytocinergic system may be involved in maladaptive coping mechanisms in the framework of impaired mentalizing and associated dysfunctional responses to interpersonal challenges in schizophrenia.
The ‘Stroke Complications after Traumatic Experiences and Stress’ (SATURN) study was designed to investigate the effects of a prior traumatic event on PTSD symptoms triggered by a subsequent stroke. ...First-ever ischemic stroke patients were surveyed 9–13 months after hospitalization at the Charité University Medical Center. Stroke-induced PTSD symptoms were measured using the Impact of Event Scale-revised (IES-R). Prior traumatization together with past PTSD symptoms was assessed retrospectively with the Brief Trauma Questionnaire (BTQ) and the 7-item Short Screening Scale for PTSD. Depressive symptoms were assessed with the Beck Depression Inventory (BDI-II). The Short Form (SF)-36 was used to evaluate physical and mental health outcomes. We received 258 responses from 636 eligible patients (~41%). Based on respondents' scores on the IES-R, the prevalence of probable PTSD due to the stroke event was 11% in our sample. Female sex and younger age were associated with more severe PTSD symptoms. Psychological endpoints did not differ between patients who denied prior trauma exposure and those who reported earlier trauma exposure but denied subsequent PTSD symptoms. However, a history of trauma exposure in tandem with endorsing subsequent PTSD symptoms was linked with significantly increased post-stroke PTSD and depressive symptoms together with decreased psychological well-being. Self-reported physical health did not differ across groups. Younger age, being a woman, and having developed PTSD symptoms in the aftermath of a prior trauma were associated with adverse psychological outcomes after stroke.
Microglia senescence may promote neuropsychiatric disease. This prompted us to examine the relationship between microglia activation states and telomere biology. A panel of candidate genes associated ...with telomere maintenance, mitochondrial biogenesis, and cell-cycle regulation were investigated in M1- and M2-polarized microglia in vitro as well as in MACS-purified CD11b+ microglia/brain macrophages from models of stroke, Alzheimer’s disease, and chronic stress. M1 polarization, ischemia, and Alzheimer pathology elicited a strikingly similar transcriptomic profile with, in particular, reduced expression of murine
Tert
. Our results link classical microglia activation with repression of telomere-associated genes, suggesting a new mechanism underlying microglia dysfunction.
Abstract
Background
Oxytocin (OXT) is critically involved in the regulation of attachment and interpersonal function. In this study, emotional children’s movies were used to stimulate OXT secretion ...in patients with schizophrenia and healthy controls (HCs). Furthermore, associations of OXT levels with measures of attachment style (Psychosis Attachment Measure), childhood adversity (Childhood Trauma Questionnaire) and symptom severity Positive and Negative Syndrome Scale (PANSS) were considered.
Methods
In 35 patients with schizophrenia and 35 matched HCs, radioimmunoassay with sample extraction was used to determine OXT plasma levels before and after viewing of movie scenes portraying emotional bonding and loss and compared to a non-emotional condition.
Results
Statistical analysis indicated lower baseline OXT levels in female patients than in all other groups. OXT reactivity during emotional movies was significantly higher in patients when compared to HCs. OXT reactivity during the control movie related to PANSS `general psychopathology’. No significant associations appeared between baseline or induced OXT levels and other PANSS subscales, attachment style or childhood adversity in patients.
Conclusions
Our findings suggest differences of baseline OXT and a higher OXT reactivity toward strong emotional stimuli in patients with schizophrenia, suggesting a role of OXT as a gender- and context-dependent modulator of socio-emotional function.
Serum BDNF concentrations in 2053 participants of the Berlin Aging Study II (BASE-II; 1572 individuals from the older age group 60–85 years, 481 individuals from the younger-age reference group 22–37 ...years) were studied. There was no effect of age, sex, body mass index, self-reported depression, or BDNF Val66Met variant on serum BDNF concentrations. Multiple linear regression analysis failed to detect significant relationships of Digit Symbol Substitution Test score and Consortium to Establish a Registry for Alzheimer's Disease memory score to BDNF levels. However, we detected a positive correlation between platelet counts and BDNF levels (r = 0.303, p < 0.001). Our findings do not support an effect of aging, self-reported depression, or the Val66Met variant on serum BDNF concentrations. The role of thrombocytes in the biology of serum BDNF merits further study.
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