Background: Vascular endothelial growth factor (VEGF) is a key regulator of angiogenesis and is implicated in the development of diabetic microvascular and macrovascular disease.
Methods: The expression of total VEGF, VEGF splice variants (VEGF(121), VEGF(145), VEGF(148), VEGF(165), VEGF(183) and VEGF(189)), VEGFR-1 and VEGFR-2, was investigated in biopsies from the right atrium and left internal mammary artery (LIMA) of 32 non-diabetic and 20 diabetic patients undergoing coronary artery bypass grafting.
Results: Diabetes was independently negatively correlated to total VEGF mRNA expression in atrium. Total VEGF, VEGF(121) and VEGF(165) mRNA levels were upregulated in the LIMA of diabetics vs. non-diabetics. The expression of VEGF receptors in atrium and LIMA was similar between these groups. VEGF(121) and VEGF(165) were the major variants expressed, followed by VEGF(189) and VEGF(183), while VEGF(148) and VEGF(145) were detected in small amounts. The expression profile of VEGF splice variants displayed significant heterogeneity between the examined tissues.
Conclusions: This is the first study to quantify VEGF splice variants expression in cardiac and vascular tissue. Our results could help elucidate the role of VEGF splice variants in diabetic complications.