APOE and triple-A syndrome: Matrix metalloproteinases (MMPs) play a crucial role in the pathological process of AAA, especially VSMC‐derived MMP‐2 and macrophage‐derived MMP‐9.[16] We therefore, examined the expression and activity of MMP‐9 in aortic tissues from ApoE−/−;Senp3flox/flox and ApoE−/−;Senp3△Mø mice infused with AngII or saline.