Platelet and Red Blood Cell Indices in Patients with Panic Disorder: A Receiver Operating Characteristic Analysis

Ambient particulate air pollution, blood cell parameters, and effect modification by psychosocial stress: Findings from two studies in three major Chinese cities

The associations between particulate matter (PM) exposure, psychosocial stress and blood cell parameters are bringing novel insights to characterize the early damage of multiple diseases. Based on two studies conducted in three Chinses cities using cross-sectional (Beijing, 425 participants) and panel study (Tianjin and Shanghai, 92 participants with 361 repeated measurements) designs, this study explored the associations between short-term exposure to ambient PM and blood cell parameters, and the effect modification by psychosocial stress. Increasing PM_2.5 exposure was significantly associated with decreases in red blood cell (RBC) count and mean corpuscular hemoglobin concentration (MCHC), and increases in mean corpuscular volume (MCV), platelets count (PLT) and platelet hematocrit (PCT) in both studies. For instance, a 10 μg/m³ increment in PM_2.5 concentration was associated with a 1.04% (95%CI: 0.16%, 1.92%) increase in PLT (4-d) and a 1.09% (95%CI: 0.31%, 1.87%) increase in PCT (4-d) in the cross-sectional study, and a 0.64% (95%CI: 0.06%, 1.22%) increase in PLT (1-d) and a 0.72% (95%CI: 0.33%, 1.11%) increase in PCT (1-d) in the panel study, respectively. In addition, stronger increases in MCV, PLT, and PCT associated with PM_2.5 exposure were found in higher psychosocial stress group compared to lower psychosocial stress group (p for interaction <0.10), indicating that blood cell parameters of individuals with higher psychosocial stress might be more susceptible to the early damages of PM_2.5 exposure.

DNA-methylation dynamics across short-term, exposure-containing CBT in patients with panic disorder

Interaction of genetic predispositions and environmental factors via epigenetic mechanisms have been hypothesized to play a central role in Panic Disorder (PD) aetiology and therapy. Cognitive Behavioral Therapy (CBT), including exposure interventions, belong to the most efficient treatments of PD although its biological mechanism of action remains unknown. For the first time, we explored the dynamics and magnitude of DNA-methylation and immune cell-type composition during CBT (n = 38) and the therapeutic exposure intervention (n = 21) to unravel their biological correlates and identify possible biomarkers of therapy success. We report transient regulation of the CD4 + T-Cells, Natural Killers cells, Granulocytes during exposure and a significant change in the proportions of CD4 + T cells, CD8 + T cells and B-Cells and Granulocytes during therapy. In an epigenome-wide association study we identified cg01586609 located in a CpG island and annotated to the serotonin receptor 3 A (HTR3A) to be differentially methylated during fear exposure and regulated at gene expression level with significant differences between remitters and non-remitters (p = 0.028). We moreover report cg01699630 annotated to ARG1 to undergo long lasting methylation changes during therapy (paired t test, genome-wide adj.p value = 0.02). This study reports the first data-driven biological candidates for epigenetically mediated effects of acute fear exposure and CBT in PD patients. Our results provide evidence of changes in the serotonin receptor 3 A methylation and expression during fear exposure associated with different long-term CBT trajectories and outcome, making it a possible candidate in the search of markers for therapy success. Finally, our results add to a growing body of evidence showing immune system changes associated with PD.

Beyond Haemostasis and Thrombosis: Platelets in Depression and Its Co-Morbidities

Alongside their function in primary haemostasis and thrombo-inflammation, platelets are increasingly considered a bridge between mental, immunological and coagulation-related disorders. This review focuses on the link between platelets and the pathophysiology of major depressive disorder (MDD) and its most frequent comorbidities. Platelet- and neuron-shared proteins involved in MDD are functionally described. Platelet-related studies performed in the context of MDD, cardiovascular disease, and major neurodegenerative, neuropsychiatric and neurodevelopmental disorders are transversally presented from an epidemiological, genetic and functional point of view. To provide a complete scenario, we report the analysis of original data on the epidemiological link between platelets and depression symptoms suggesting moderating and interactive effects of sex on this association. Epidemiological and genetic studies discussed suggest that blood platelets might also be relevant biomarkers of MDD prediction and occurrence in the context of MDD comorbidities. Finally, this review has the ambition to formulate some directives and perspectives for future research on this topic.