Angiogenesis and vascular remodeling are impaired in AD as evidenced by altered expression profiles of several angiogenic factors, such as VEGF, vascular-restricted mesenchyme homeobox-2 (MEOX2), MMP-9, angiopoietin-2, integrins (αvβ3 and αvβ5), and the transferrin receptor, leading to vascular regression and abnormal vessel sprouting [191,192]. Here, MMP9 is linked to Alzheimer disease.