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Nieratschker, V.

Publications and source records attributed to Nieratschker, V..

4 recordsLinked to original sources

Dynamic transcriptional remodeling in alcohol use disorder reveals immune dysregulation and adaptive shifts in coagulation during therapy

BackgroundChronic alcohol use disorder (AUD) is associated with profound dysregulation of immune function, neuroinflammation, and systemic stress responses, which contribute to both the maintenance of addiction and alcohol-related organ damage. While brain transcriptomic studies have established neuroimmune signaling and synaptic remodeling as central features of AUD, peripheral blood signatures during early withdrawal and recovery remain underexplored. Understanding the dynamic transcriptional changes in peripheral blood accompanying supervised withdrawal therapy is critical for identifying reversible molecular processes versus persistent trait-like alterations. MethodsRNA sequencing (RNA-seq) was performed on peripheral blood from individuals with alcohol use disorder (AUD, n = 100) and healthy controls (n = 74) at baseline and after three weeks of supervised withdrawal therapy. Differentially expressed genes (DEGs) were identified using linear mixed models assessing main effects of group, time, and their interaction. Functional enrichment and co-expression network analyses were performed to identify coordinated biological processes. ResultsAt baseline, more than 1,000 genes were differentially expressed between AUD and control participants, showing robust dysregulation of immune-related pathways. After three weeks of withdrawal, the number of DEGs decreased markedly to 141, indicating partial transcriptomic normalization. Nevertheless, immune dysregulation persisted despite treatment, particularly linked to B cell activation and cell-cell junctions. Interaction analyses (group x time) identified 16 genes whose expression dynamically changed with therapy, highlighting strong enrichment for fatty acid pathways. Co-expression network analysis revealed that baseline modules were enriched for genes associated with secretory granules and immune signaling, while therapy-related co-expression shifts involved coagulation and platelet activation processes. ConclusionsAUD is associated with widespread but partly reversible transcriptomic dysregulation in peripheral blood. These findings support a system-level view of AUD as a disorder of intertwined immune, metabolic, and coagulation biology and suggest that longitudinal blood transcriptomics may help identify both rapidly therapy-responsive and more stable molecular targets for relapse prevention.

molecular biology↗

Social stress, cortisol awakening response and sex: Impact on hippocampus and amygdala volume

ObjectiveVolumes of the hippocampus and amygdala, both major hubs for neural stress regulation amongst others, are influenced by social stressors, cortisol awakening response (CAR) and sex, i.e. psychological and physiological stress factors. Importantly, the interplay of these different factors in affecting the morphology of both brain regions remains unclear. This study aimed to elucidate the intricate influence of these factors on grey matter volumes (GMV) of the hippocampus and amygdala. MethodsWe analyzed associations between structural brain data, self-reported chronic social stress (including subscales on social tension, social overload, lack of social recognition and social isolation) and CAR of 83 healthy participants (40 females) with multiple regression analyses. ResultsIn males, but not females, higher social tension predicted lower bilateral hippocampus GMV. In individuals not showing the typical CAR, higher social tension predicted reduced bilateral hippocampus GMV. Amygdala GMV was also related to social stress and CAR, with social overload associated with reduced amygdala GMV in individuals not showing the typical CAR, while the opposite pattern emerged in those with an atypical CAR. ConclusionsChronic social stress is associated with hippocampus and amygdala volumes, interacting with CAR and sex. The brain morphology in males and in individuals with atypical CAR seems to be more vulnerable to chronic social stress. Our findings enhance our understanding of how brain architecture, social stress, CAR patterns and sex shape individual stress responses.

neuroscience↗

Blood transcriptome analysis suggests an indirect molecular association of early life adversities and adult social anxiety disorder by immune-related signal transduction

Social anxiety disorder (SAD) is a psychiatric disorder characterized by severe fear in social situations and avoidance of these. Multiple genetic as well as environmental factors contribute to the etiopathology of SAD. One of the main risk factors for SAD is stress, especially during early periods of life (early life adversity; ELA). ELA leads to structural and regulatory alterations contributing to disease vulnerability. This includes the dysregulation of the immune response. However, the molecular link between ELA and the risk for SAD in adulthood remain largely unclear. Evidence is emerging that long-lasting changes of gene expression patterns play an important role in the biological mechanisms linking ELA and SAD. Therefore, we performed a transcriptome study of SAD and ELA using RNA sequencing. Analyzing differential gene expression, 13 significantly differentially expressed genes (DEGs) were identified with respect to SAD whilst no significant differences in expression were identified with respect to ELA. The most significantly expressed gene was MAPK3 being upregulated in the SAD group compared to control individuals. In contrary, weighted gene co-expression network analyses (WGCNA) identified only modules significantly associated with ELA, not with SAD. Furthermore, analyzing interaction networks of the genes from the ELA-associated modules and the SAD-related MAPK3) revealed complex interactions of those genes. Gene functional enrichment analyses indicate a role of signal transduction pathways as well as inflammatory responses supporting an involvement of the immune system in the association of ELA and SAD. In conclusion, we did not identify a direct molecular link between ELA and adult SAD by transcriptional changes. However, our data indicate an indirect association of ELA and SAD mediated by the interaction of genes involved in immune-related signal transduction.

genomics↗

Dynamic DNA methylation changes in the COMT gene promoter region in response to mental stress and its modulation by transcranial direct current stimulation

Changes in epigenetic modifications present a mechanism how environmental factors like the experience of stress can alter gene regulation. While stress-related disorders have consistently been associated with differential DNA methylation, little is known about the time scale in which these alterations emerge. We investigated dynamic DNA methylation changes in whole blood of 42 healthy male individuals in response to a stressful cognitive task, its association with concentration changes in cortisol and its modulation by transcranial direct current stimulation (tDCS). We observed a continuous increase in COMT promotor DNA methylation which correlated with higher saliva cortisol levels and was still detectable one week later. However, this lasting effect was suppressed by concurrent activity-enhancing anodal tDCS to the dorsolateral prefrontal cortex. Our findings support the significance of gene-specific DNA methylation in whole blood as potential biomarkers for stress-related disorders. Moreover, they suggest alternative molecular mechanisms possibly involved in lasting behavioral effects of tDCS.

neuroscience↗