Key dimensions of post-traumatic stress disorder and endothelial dysfunction: a protocol for a mechanism-focused cohort study

Association of Cardiovascular Diseases With Post-Traumatic Stress Disorder: An Updated Review

The intricate relationship between post-traumatic stress disorder (PTSD) and cardiovascular disease (CVD) has garnered increasing attention due to its bidirectional impact and potential for significant health consequences. Epidemiological evidence suggests that PTSD may serve as a risk factor for incident CVD, while acute CVD events can trigger PTSD, subsequently increasing the risk of recurrent cardiovascular events. This dynamic interplay is characterized by the human stress response, disrupted behavioral and lifestyle factors, and potential physiological mechanisms. Notably, the immediate aftermath of a cardiovascular event presents a critical window for intervention, offering the possibility of preventing the development of PTSD and its associated physiological and behavioral sequelae. However, while candidate mechanisms linking PTSD and CVD have been identified, determining which mechanisms are most amenable to intervention remains a challenge. This article emphasizes the urgency of addressing key unanswered questions in this domain. Despite an evolving understanding of the association between PTSD and CVD, causal relationships remain to be firmly established. Comprehensive investigations into the intricate interplay of behavioral and biological mechanisms are essential for identifying precise targets for intervention. Innovations in research methodologies, including the exploration of PTSD symptom dynamics and their impact on cardiovascular function, hold the potential for identifying crucial intervention points. Drawing parallels from prior challenges in translating identified risk factors into effective interventions, the field must prioritize systematic investigations and early-phase intervention trials. By doing so, researchers and clinicians can potentially develop strategies to mitigate CVD risk in the context of PTSD and improve both cardiovascular and mental health outcomes.

Cerebral Blood Flow in Predator Stress-Resilient and -Susceptible Rats and Mechanisms of Resilience

Stress-induced conditions are associated with impaired cerebral blood flow (CBF) and increased risk of dementia and stroke. However, these conditions do not develop in resilient humans and animals. Here the effects of predator stress (PS, cat urine scent, ten days) on CBF and mechanisms of CBF regulation were compared in PS-susceptible (PSs) and PS-resilient (PSr) rats. Fourteen days post-stress, the rats were segregated into PSs and PSr groups based on a behavior-related anxiety index (AI). CBF and its endothelium-dependent changes were measured in the parietal cortex by laser Doppler flowmetry. The major findings are: (1) PS susceptibility was associated with reduced basal CBF and endothelial dysfunction. In PSr rats, the basal CBF was higher, and endothelial dysfunction was attenuated. (2) CBF was inversely correlated with the AI of PS-exposed rats. (3) Endothelial dysfunction was associated with a decrease in eNOS mRNA in PSs rats compared to the PSr and control rats. (4) Brain dopamine was reduced in PSs rats and increased in PSr rats. (5) Plasma corticosterone of PSs was reduced compared to PSr and control rats. (6) A hypercoagulation state was present in PSs rats but not in PSr rats. Thus, potential stress resilience mechanisms that are protective for CBF were identified.

PTSD as an Endothelial Disease: Insights From COVID-19

SARS-CoV-2 virus, the etiologic agent of COVID-19, has affected almost every aspect of human life, precipitating stress-related pathology in vulnerable individuals. As the prevalence rate of posttraumatic stress disorder in pandemic survivors exceeds that of the general and special populations, the virus may predispose to this disorder by directly interfering with the stress-processing pathways. The SARS-CoV-2 interactome has identified several antigens that may disrupt the blood-brain-barrier by inducing premature senescence in many cell types, including the cerebral endothelial cells. This enables the stress molecules, including angiotensin II, endothelin-1 and plasminogen activator inhibitor 1, to aberrantly activate the amygdala, hippocampus, and medial prefrontal cortex, increasing the vulnerability to stress related disorders. This is supported by observing the beneficial effects of angiotensin receptor blockers and angiotensin converting enzyme inhibitors in both posttraumatic stress disorder and SARS-CoV-2 critical illness. In this narrative review, we take a closer look at the virus-host dialog and its impact on the renin-angiotensin system, mitochondrial fitness, and brain-derived neurotrophic factor. We discuss the role of furin cleaving site, the fibrinolytic system, and Sigma-1 receptor in the pathogenesis of psychological trauma. In other words, learning from the virus, clarify the molecular underpinnings of stress related disorders, and design better therapies for these conditions. In this context, we emphasize new potential treatments, including furin and bromodomains inhibitors.