However, diabetic patients and diabetic animal models often exhibit defective VEGF/VEGFR-2 [5,6,7] and angiopoietin-1 (Ang-1)/Tie-2 [8,9] signaling transduction, which has been demonstrated to play an important role in diabetes-related impairment of angiogenesis. This evidence concerns the gene ANGPT1 and diabetes mellitus.