The effects of stress on brain and adrenal stem cells

Bibliometric analysis of post-traumatic stress disorder in forensic medicine: Research trends, hot spots, and prospects

Background

Post-traumatic stress disorder (PTSD) has various risk factors, complex pathogenesis, and diverse symptoms, and is often comorbid with other injuries and diseases, making forensic diagnosis difficult.

Methods

To explore the current research status and trends of PTSD, we used the Web of Science Core Collection databases to screen PTSD-related literature published between 2010 and 2021 and CiteSpace to perform bibliometric analysis.

Results

In recent years, PTSD-related research has grown steadily. The countries and institutions with the most research results were the United States and England, and King's College London and Boston University, respectively. Publications were identified from 2,821 different journals, including 13 forensic-related journals, but the journal distribution was relatively scattered and there was a lack of professional core journals. Keyword co-occurrence and clustering identified many hot topics; "rat model," "mental health," and "satisfaction" were the topics most likely to have a clear effect on future research. Analysis extracted nine turning points from the literature that suggested that neural network centers, the hypothalamic-pituitary-adrenal axis, and biomarkers were new research directions. It was found that COVID-19 can cause severe psychological stress and induce PTSD, but the relationship needs further study. The literature on stress response areas and biomarkers has gradually increased over time, but specific systemic neural brain circuits and biomarkers remain to be determined.

Conclusion

There is a need to expand the collection of different types of biological tissue samples from patients with different backgrounds, screen PTSD biomarkers and molecular targets using multi-omics and molecular biology techniques, and establish PTSD-related molecular networks. This may promote a systematic understanding of the abnormal activation of neural circuits in patients with PTSD and help to establish a personalized, accurate, and objective forensic diagnostic standard.

The Degree Centrality and Functional Connectivity in Patients With Temporal Lobe Epilepsy Presenting as Ictal Panic: A Resting State fMRI Study

Objectives

Ictal panic (IP) can be observed occasionally in patients with temporal lobe epilepsy (TLE). Such descriptions can be found in previous studies, but the mechanism is still not clear and often confused with panic attacks in patients with panic disorder (PD). We try to use imaging methods (resting-state functional magnetic resonance imaging, rs-fMRI) to study the mechanism of this psychiatric comorbidity in patients with TLE.

Methods

Forty right-onset TLE patients were observed, including 28 patients with TLE but without IP and 12 patients with TLEIP along with 30 gender-age matched healthy controls were included. We collected clinical/physiological/neuropsychological and rs-fMRI data. Degree centrality (DC) and functional connectivity (FC) were calculated. For the DC and FC values, analysis of covariance (ANCOVA) was used to find different areas and t-tests were used to compare differences between the TLEIP, TLE without IP, and healthy control(HC)groups. The relationship between brain abnormalities and patient characteristics was explored by correlation analyses.

Results

No significant differences in gender and age were found among the three groups, and no significant differences in education level, Montreal Cognitive Assessment (MOCA), Hamilton Depressive Scale (HAMD), Hamilton Anxiety Scale (HAMA), and epilepsy duration (years) between the TLEIP and TLE without IP groups. In addition to fear, other symptoms were observed, including nausea, palpitations, rising epigastric sensation, and dyspnea. There was no correlation between the duration of IP and HAMA. Moreover, all IP durations were <2 min. Compared to the HCs and TLE without IP group, the DC value of the TLEIP group in the left middle temporal gyrus (LMTG) was significantly increased. Compared to the HCs, FC could be found between the LMTG and left inferior temporal gyrus (LITG) in the TLEIP group. In addition, there was FC between the LMTG and cerebellum in the TLEIP group. The difference in the magnitude of FC between the TLEIP vs. HC group was greater than the difference between the TLE vs. HC group.

Conclusions

This study describes brain abnormalities in patients with TLEIP. These results will help to preliminarily understand the mechanism of ictal panic and abnormal functional connection in patients with TLE, and further explore the neuroimaging mechanism of ictal panic in patients with TLE.

Mini-review: Elucidating the psychological, physical, and sex-based interactions between HIV infection and stress

Stress is generally classified as any mental or emotional strain resulting from difficult circumstances, and can manifest in the form of depression, anxiety, post-traumatic stress disorder (PTSD), or other neurocognitive disorders. Neurocognitive disorders such as depression, anxiety, and PTSD are large contributors to disability worldwide, and continue to affect individuals and communities. Although these disorders affect men and women, women are disproportionately represented among those diagnosed with affective disorders, a result of both societal gender roles and physical differences. Furthermore, the incidence of these neurocognitive disorders is augmented among People Living with HIV (PLWH); the physical ramifications of stress increase the likelihood of HIV acquisition, pathogenesis, and treatment, as both stress and HIV infection are characterized by chronic inflammation, which creates a more opportunistic environment for HIV. Although the stress response is facilitated by the autonomic nervous system (ANS) and the hypothalamic pituitary adrenal (HPA) axis, when the response involves a psychological component, additional brain regions are engaged. The impact of chronic stress exposure and the origin of individual variation in stress responses and resilience are at least in part attributable to regions outside the primary stress circuity, including the amygdala, prefrontal cortex, and hippocampus. This review aims to elucidate the relationship between stress and HIV, how these interact with sex, and to understand the physical ramifications of these interactions.

Ictal fear is associated with anxiety symptoms and interictal dysphoric disorder in drug-resistant mesial temporal lobe epilepsy

Interictal dysphoric disorder (IDD) is a poorly understood psychiatric disorder of epilepsy patients. Interictal dysphoric disorder is characterized by depressive, somatoform, and affective symptoms observed in up to 5.9% of drug-resistant mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS). This study aimed to evaluate the association between ictal fear (IF) and the psychiatric symptoms and diagnosis in MTLE-HS patients. We included 116 (54.3% male) consecutive adult patients (36 ± 11 years) with MTLE-HS. Anxiety and depression symptoms were evaluated by the Hospital Anxiety and Depression Scale (HADS) and the psychiatric diagnosis were according to Fourth Edition of the Diagnosis and Statistical Manual of Mental Disorders (DSM-IV). The independent association between the occurrence of IF aura and the psychiatric diagnosis was determined by binary regression. When compared to those with other auras or without aura, patients reporting IF have higher HADS anxiety, but not HADS depression, scores. Ictal fear was independently associated with the diagnosis of interictal dysphoric disorder (OR, IC 95% = 7.6, 1.3-43.2, p = 0.02), but not with the diagnosis of anxiety (OR, CI 95% = 0.72, 0.08-6.0, p = 0.73), depression (OR, CI 95% = 0.94, 0.19-4.8, p = 0.94) or psychotic disorders (p = 0.99). Only patients with drug-resistant MTLE-HS were included and the small number of cases with DD diagnosis in the sample. In MTLE-HS patients, the occurrence of IF is associated with higher levels of anxiety symptoms and IDD. The results provide insights about fear-related neural network connections with anxiety symptoms and the IDD in MTLE-HS.

Secretory galectin-3 induced by glucocorticoid stress triggers stemness exhaustion of hepatic progenitor cells

Adult progenitor cell populations typically exist in a quiescent state within a controlled niche environment. However, various stresses or forms of damage can disrupt this state, which often leads to dysfunction and aging. We built a glucocorticoid (GC)-induced liver damage model of mice, found that GC stress induced liver damage, leading to consequences for progenitor cells expansion. However, the mechanisms by which niche factors cause progenitor cells proliferation are largely unknown. We demonstrate that, within the liver progenitor cells niche, Galectin-3 (Gal-3) is responsible for driving a subset of progenitor cells to break quiescence. We show that GC stress causes aging of the niche, which induces the up-regulation of Gal-3. The increased Gal-3 population increasingly interacts with the progenitor cell marker CD133, which triggers focal adhesion kinase (FAK)/AMP-activated kinase (AMPK) signaling. This results in the loss of quiescence and leads to the eventual stemness exhaustion of progenitor cells. Conversely, blocking Gal-3 with the inhibitor TD139 prevents the loss of stemness and improves liver function. These experiments identify a stress-dependent change in progenitor cell niche that directly influence liver progenitor cell quiescence and function.

The role of the GABAA receptor Alpha 1 subunit in the ventral hippocampus in stress resilience

Pre-pubertal stress increases post-traumatic stress disorder (PTSD) susceptibility. We have previously demonstrated that enriched environment (EE) intervention immediately after pre-pubertal stress protects from the effects of trauma in adulthood. Here, we examined whether exposure to EE would also be beneficial if applied after exposure to trauma in adulthood. We have recently shown that exposure to juvenile stress and under-water trauma (UWT) is associated with increased expression of GABA_A receptor subunit α1 in the ventral hippocampus. However, differentiating between affected and unaffected individuals, this increased expression was confined to stress-exposed, behaviorally unaffected individuals, suggesting upregulation of α1 expression as a potential mechanism of resilience. We now examined whether EE-induced resilience renders increased expression of α1 in the ventral hippocampus redundant when facing a trauma later in life. Adult rats were exposed to UWT, with pre-exposure to juvenile stress, and tested in the open field and elevated plus maze paradigms four weeks later. EE exposure during juvenility prevented pre-pubertal stress-induced vulnerability, but not if performed following UWT in adulthood. Furthermore, juvenile EE exposure prevented the trauma-associated increase in α1 expression levels. Our findings emphasize the importance of early interventions in order to reduce the likelihood of developing psychopathologies in adulthood.

Differential effects of chronic stress in young-adult and old female mice: cognitive-behavioral manifestations and neurobiological correlates

Stress-related psychopathology is highly prevalent among elderly individuals and is associated with detrimental effects on mood, appetite and cognition. Conversely, under certain circumstances repeated mild-to-moderate stressors have been shown to enhance cognitive performance in rodents and exert stress-inoculating effects in humans. As most stress-related favorable outcomes have been reported in adolescence and young-adulthood, this apparent disparity could result from fundamental differences in how aging organisms respond to stress. Furthermore, given prominent age-related alterations in sex hormones, the effect of chronic stress in aging females remains a highly relevant yet little studied issue. In the present study, female C57BL/6 mice aged 3 (young-adult) and 20-23 (old) months were subjected to 8 weeks of chronic unpredictable stress (CUS). Behavioral outcomes were measured during the last 3 weeks of the CUS protocol, followed by brain dissection for histological and molecular end points. We found that in young-adult female mice, CUS resulted in decreased anxiety-like behavior and enhanced cognitive performance, whereas in old female mice it led to weight loss, dysregulated locomotion and memory impairment. These phenotypes were paralleled by differential changes in the expression of hypothalamic insulin and melanocortin-4 receptors and were consistent with an age-dependent reduction in the dynamic range of stress-related changes in the hippocampal transcriptome. Supported by an integrated microRNA (miRNA)-mRNA expression analysis, the present study proposes that, when confronted with ongoing stress, neuroprotective mechanisms involving the upregulation of neurogenesis, Wnt signaling and miR-375 can be harnessed more effectively during young-adulthood. Conversely, we suggest that aging alters the pattern of immune activation elicited by stress. Ultimately, interventions that modulate these processes could reduce the burden of stress-related psychopathology in late life.

Inverse association between hyperthymic affective temperament and coronary atherosclerosis: A coronary computed tomography angiography study

OBJECTIVE

A bidirectional relationship exists between psychiatric disorders and cardiovascular diseases, however less is known with regards to personality traits. Accumulating data suggest that affective temperaments are both associated with psychiatric and somatic diseases. The aim of our study was to evaluate the associations between different affective temperaments and the presence of coronary atherosclerosis.

METHODS

200 consecutive patients referred to coronary computed tomography angiography (CCTA) due to suspected coronary artery disease (CAD) were included in our study. Medical history and demographic parameters were recorded and all patients completed the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego Autoquestionnaire (TEMPS-A) and the Beck Depression Inventory (BDI). The presence of coronary artery disease was evaluated based on the CCTA images.

RESULTS

39 patients were free of any coronary atherosclerosis (CCTA-) and 161 had coronary atherosclerosis (CCTA+). Hyperthymic affective temperament score was higher in CCTA- subjects as compared to CCTA+ (13.1±3.0 vs 11.5±4.6, p=0.010, respectively). Hyperthymic affective temperament score showed a significant independent, inverse relationship with coronary atherosclerosis (OR: 0.91 CI: 0.82-0.99, p=0.04).

CONCLUSION

Our results suggest that hyperthymic affective temperament is independently associated with the absence of CAD. It requires further research to delineate the mechanism mediating the effect of hyperthymia on better coronary artery health and establishing potential biochemical or behavioral factors, both of which could be exploited for prevention and treatment purposes. But it is plausible, that the evaluation of affective temperaments have importance both in relation with psychiatric and cardiovascular disorders.

Disrupted-in-Schizophrenia-1 is essential for normal hypothalamic-pituitary-interrenal (HPI) axis function

Psychiatric disorders arise due to an interplay of genetic and environmental factors, including stress. Studies in rodents have shown that mutants for Disrupted-In-Schizophrenia-1 (DISC1), a well-accepted genetic risk factor for mental illness, display abnormal behaviours in response to stress, but the mechanisms through which DISC1 affects stress responses remain poorly understood. Using two lines of zebrafish homozygous mutant for disc1, we investigated behaviour and functioning of the hypothalamic-pituitary-interrenal (HPI) axis, the fish equivalent of the hypothalamic-pituitary-adrenal (HPA) axis. Here, we show that the role of DISC1 in stress responses is evolutionarily conserved and that DISC1 is essential for normal functioning of the HPI axis. Adult zebrafish homozygous mutant for disc1 show aberrant behavioural responses to stress. Our studies reveal that in the embryo, disc1 is expressed in neural progenitor cells of the hypothalamus, a conserved region of the vertebrate brain that centrally controls responses to environmental stressors. In disc1 mutant embryos, proliferating rx3+ hypothalamic progenitors are not maintained normally and neuronal differentiation is compromised: rx3-derived ff1b+ neurons, implicated in anxiety-related behaviours, and corticotrophin releasing hormone (crh) neurons, key regulators of the stress axis, develop abnormally, and rx3-derived pomc+ neurons are disorganised. Abnormal hypothalamic development is associated with dysfunctional behavioural and neuroendocrine stress responses. In contrast to wild type siblings, disc1 mutant larvae show altered crh levels, fail to upregulate cortisol levels when under stress and do not modulate shoal cohesion, indicative of abnormal social behaviour. These data indicate that disc1 is essential for normal development of the hypothalamus and for the correct functioning of the HPA/HPI axis.

Adrenal cortical and chromaffin stem cells: Is there a common progeny related to stress adaptation?

The adrenal gland is a highly plastic organ with the capacity to adapt the body homeostasis to different physiological needs. The existence of stem-like cells in the adrenal cortex has been revealed in many studies. Recently, we identified and characterized in mice a pool of glia-like multipotent Nestin-expressing progenitor cells, which contributes to the plasticity of the adrenal medulla. In addition, we found that these Nestin progenitors are actively involved in the stress response by giving rise to chromaffin cells. Interestingly, we also observed a Nestin-GFP-positive cell population located under the adrenal capsule and scattered through the cortex. In this article, we discuss the possibility of a common progenitor giving rise to subpopulations of cells both in the adrenal cortex and medulla, the isolation and characterization of this progenitor as well as its clinical potential in transplantation therapies and in pathophysiology.

A single high dose of dexamethasone affects the phosphorylation state of glutamate AMPA receptors in the human limbic system

Glucocorticoids (GC) released during stress response exert feedforward effects in the whole brain, but particularly in the limbic circuits that modulates cognition, emotion and behavior. GC are the most commonly prescribed anti-inflammatory and immunosuppressant medication worldwide and pharmacological GC treatment has been paralleled by the high incidence of acute and chronic neuropsychiatric side effects, which reinforces the brain sensitivity for GC. Synapses can be bi-directionally modifiable via potentiation (long-term potentiation, LTP) or depotentiation (long-term depression, LTD) of synaptic transmission efficacy, and the phosphorylation state of Ser831 and Ser845 sites, in the GluA1 subunit of the glutamate AMPA receptors, are a critical event for these synaptic neuroplasticity events. Through a quasi-randomized controlled study, we show that a single high dexamethasone dose significantly reduces in a dose-dependent manner the levels of GluA1-Ser831 phosphorylation in the amygdala resected during surgery for temporal lobe epilepsy. This is the first report demonstrating GC effects on key markers of synaptic neuroplasticity in the human limbic system. The results contribute to understanding how GC affects the human brain under physiologic and pharmacologic conditions.

Adrenal Gland Microenvironment and Its Involvement in the Regulation of Stress-Induced Hormone Secretion during Sepsis

Survival of all living organisms depends on maintenance of a steady state of homeostasis, which process relies on its ability to react and adapt to various physical and emotional threats. The defense against stress is executed by the hypothalamic-pituitary-adrenal axis and the sympathetic-adrenal medullary system. Adrenal gland is a major effector organ of stress system. During stress, adrenal gland rapidly responds with increased secretion of glucocorticoids (GCs) and catecholamines into circulation, which hormones, in turn, affect metabolism, to provide acutely energy, vasculature to increase blood pressure, and the immune system to prevent it from extensive activation. Sepsis resulting from microbial infections is a sustained and extreme example of stress situation. In many critical ill patients, levels of both corticotropin-releasing hormone and adrenocorticotropin, the two major regulators of adrenal hormone production, are suppressed. Levels of GCs, however, remain normal or are elevated in these patients, suggesting a shift from central to local intra-adrenal regulation of adrenal stress response. Among many mechanisms potentially involved in this process, reduced GC metabolism and activation of intra-adrenal cellular systems composed of adrenocortical and adrenomedullary cells, endothelial cells, and resident and recruited immune cells play a key role. Hence, dysregulated function of any of these cells and cellular compartments can ultimately affect adrenal stress response. The purpose of this mini review is to highlight recent insights into our understanding of the adrenal gland microenvironment and its role in coordination of stress-induced hormone secretion.