MRC1 and Aortic dissection: Another study reported that aging female mice, but not male mice, showed activation of transforming growth factor (TGF)-β pathway, which is involved in the pathogenesis of aortic dissection and aneurysm17-19), and reduced expression of C-type mannose receptor 1, a deficiency in which causes fibrosis due to reduced collagen uptake in left ventricle20).