Development of gene expression signatures of ascending aorta of the patients with bicuspid aortic valve compared to tricuspid aortic valve.

Bicuspid aortic valve is well known as a risk factor of dilation of ascending aorta. But the mechanisms of dialation are unknown. Morever, patients with bicuspid aortic valve tend to be aortic valve disease at younger age. After aortic valve surgery, if ascending aorta is dilated, the patient must be performed re-operation. For that reason, surgery for aortic root or ascending aorta is recommended to patient with bicuspid aortic valve with dilated ascending aorta. We thought that abnormality of cell cycle of the structure protein participated in ascending aorta dilation of patient with bicuspid aortic valve. We resected the wall of the ascending aota from patient undergoing aortic valve replacement for aortic valve stenosis during operation, and performed immunohistochemical staining for akt. Anti Akt antibodys were stained much on aortic media with bicuspoed aortic valve. Akt is a protein that is involved in mTOR / PI3K, and modulate the cell differenciation and proliferation. Further, the same samples were analyzed using a microarray method. On bicuspid aortic valve patients, the expression of TSC2 is reduced, and GβL is increased. TSC2 inhibit this pathway, and MLST8 activate this pathway. In the ascending aorta of BAV patients, PI3K / mTOR system is considered to be activated. When this pathway is activated, cell proliferation and cytodifferentiation are promoted abnormally, The aortic valve replacement surgery, excised the ascending aorta wall of aortotomy site, was used as a sample. We divided into 2 groups(bicuspid aortic valve vs tricuspid aortic valve) and analysed.