@article{NeuhausSchlundtFehrholzetal.2015, author = {Neuhaus, Winfried and Schlundt, Marian and Fehrholz, Markus and Ehrke, Alexander and Kunzmann, Steffen and Liebner, Stefan and Speer, Christian P. and F{\"o}rster, Carola Y.}, title = {Multiple antenatal dexamethasone treatment alters brain vessel differentiation in newborn mouse pups}, series = {PLoS ONE}, volume = {10}, journal = {PLoS ONE}, number = {8}, doi = {10.1371/journal.pone.0136221}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-148268}, pages = {e0136221}, year = {2015}, abstract = {Antenatal steroid treatment decreases morbidity and mortality in premature infants through the maturation of lung tissue, which enables sufficient breathing performance. However, clinical and animal studies have shown that repeated doses of glucocorticoids such as dexamethasone and betamethasone lead to long-term adverse effects on brain development. Therefore, we established a mouse model for antenatal dexamethasone treatment to investigate the effects of dexamethasone on brain vessel differentiation towards the blood-brain barrier (BBB) phenotype, focusing on molecular marker analysis. The major findings were that in total brains on postnatal day (PN) 4 triple antenatal dexamethasone treatment significantly downregulated the tight junction protein claudin-5, the endothelial marker Pecam-1/CD31, the glucocorticoid receptor, the NR1 subunit of the N-methyl-D-aspartate receptor, and Abc transporters (Abcb1a, Abcg2 Abcc4). Less pronounced effects were found after single antenatal dexamethasone treatment and in PN10 samples. Comparisons of total brain samples with isolated brain endothelial cells together with the stainings for Pecam-1/CD31 and claudin-5 led to the assumption that the morphology of brain vessels is affected by antenatal dexamethasone treatment at PN4. On the mRNA level markers for angiogenesis, the sonic hedgehog and the Wnt pathway were downregulated in PN4 samples, suggesting fundamental changes in brain vascularization and/or differentiation. In conclusion, we provided a first comprehensive molecular basis for the adverse effects of multiple antenatal dexamethasone treatment on brain vessel differentiation.}, language = {en} } @article{ZannasArlothCarrilloRoaetal.2015, author = {Zannas, Anthony S. and Arloth, Janine and Carrillo-Roa, Tania and Iurato, Stella and R{\"o}h, Simone and Ressler, Kerry J. and Nemeroff, Charles B. and Smith, Alicia K. and Bradley, Bekh and Heim, Christine and Menke, Andreas and Lange, Jennifer F. and Br{\"u}ckl, Tanja and Ising, Marcus and Wray, Naomi R. and Erhardt, Angelika and Binder, Elisabeth B. and Mehta, Divya}, title = {Lifetime stress accelerates epigenetic aging in an urban, African American cohort: relevance of glucocorticoid signaling}, series = {Genome Biology}, volume = {16}, journal = {Genome Biology}, number = {266}, doi = {10.1186/s13059-015-0828-5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-149865}, year = {2015}, abstract = {Background Chronic psychological stress is associated with accelerated aging and increased risk for aging-related diseases, but the underlying molecular mechanisms are unclear. Results We examined the effect of lifetime stressors on a DNA methylation-based age predictor, epigenetic clock. After controlling for blood cell-type composition and lifestyle parameters, cumulative lifetime stress, but not childhood maltreatment or current stress alone, predicted accelerated epigenetic aging in an urban, African American cohort (n = 392). This effect was primarily driven by personal life stressors, was more pronounced with advancing age, and was blunted in individuals with higher childhood abuse exposure. Hypothesizing that these epigenetic effects could be mediated by glucocorticoid signaling, we found that a high number (n = 85) of epigenetic clock CpG sites were located within glucocorticoid response elements. We further examined the functional effects of glucocorticoids on epigenetic clock CpGs in an independent sample with genome-wide DNA methylation (n = 124) and gene expression data (n = 297) before and after exposure to the glucocorticoid receptor agonist dexamethasone. Dexamethasone induced dynamic changes in methylation in 31.2 \% (110/353) of these CpGs and transcription in 81.7 \% (139/170) of genes neighboring epigenetic clock CpGs. Disease enrichment analysis of these dexamethasone-regulated genes showed enriched association for aging-related diseases, including coronary artery disease, arteriosclerosis, and leukemias. Conclusions Cumulative lifetime stress may accelerate epigenetic aging, an effect that could be driven by glucocorticoid-induced epigenetic changes. These findings contribute to our understanding of mechanisms linking chronic stress with accelerated aging and heightened disease risk.}, language = {en} }