17 -Estradiol Impedes Aortic Root Dilation and Rupture in Male Marfan Mice

Marfan syndrome causes a hereditary form of thoracic aortic aneurysms with worse outcomes in male compared to female patients. In this study, we examine the effects of 17 beta-estradiol on aortic dilation and rupture in a Marfan mouse model. Marfan male mice were administered 17 beta-estradiol, and the growth in the aortic root, along with the risk of aortic rupture, was measured. Transcriptomic profiling was used to identify enriched pathways from 17 beta-estradiol treatments. Aortic smooth muscle cells were then treated with cytokines to validate functional mechanisms. We show that 17 beta-estradiol decreased the size and rate of aortic root dilation and improved survival from rupture. The Marfan transcriptome was enriched in inflammatory genes, and the addition of 17 beta-estradiol modulated a set of genes that function through TNF alpha mediated NF-kappa B signaling. In addition, 17 beta-estradiol suppressed the induction of these TNF alpha induced genes in aortic smooth muscle cells in vitro in an NF-kappa B dependent manner, and 17 beta-estradiol decreased the formation of adventitial inflammatory foci in aortic roots in vivo. In conclusion, 17 beta-estradiol protects against the dilation and rupture of aortic roots in Marfan male mice through the inhibition of TNF alpha-NF-kappa B signaling.