Disturbed nitric oxide signalling gives rise to congenital bicuspid aortic valve and aortopathy.

Patients with a congenital bicuspid aortic valve (BAV), a valve with two instead of three aortic leaflets, have an increased risk of developing thoracic aneurysms and aortic dissection. The mechanisms underlying BAV-associated aortopathy are poorly understood. This study examined BAV-associated aortopathy in mice, a model with congenital BAV formation.

Bicuspid aortic valve formation: mutation leads to abnormal lineage patterning of neural crest cells and the second heart field.

The bicuspid aortic valve (BAV), a valve with two instead of three aortic leaflets, belongs to the most prevalent congenital heart diseases in the world, occurring in 0.5-2% of the general population. We aimed to understand how changes in early cellular contributions result in BAV formation and impact cardiovascular outflow tract development.

Intrauterine exposure to maternal atherosclerotic risk factors increases the susceptibility to atherosclerosis in adult life.

Objective: Maternal hypercholesterolemia is associated with a higher incidence and faster progression of atherosclerotic lesions in neonatal offspring. We aimed to determine whether an in utero environment exposing a fetus to maternal hypercholesterolemia and associated risk factors can prime the murine vessel wall to accelerated development of cardiovascular disease in adult life.

Methods And Results: To investigate the epigenetic effect in utero, we generated genetically identical heterozygous apolipoprotein E-deficient progeny from mothers with a wild-type or apolipoprotein E-deficient background.

Embryonic endothelial cells transdifferentiate into mesenchymal cells expressing smooth muscle actins in vivo and in vitro.

All blood vessels are lined by endothelium and, except for the capillaries, surrounded by one or more layers of smooth muscle cells. The origin of the embryonic vascular smooth muscle cell has until now been described from neural crest and locally differentiating mesenchyme. In this study, we have substantial evidence that quail embryonic endothelial cells are competent in the dorsal aorta of the embryo to transdifferentiate into subendothelial mesenchymal cells expressing smooth muscle actins in vivo.