Oxidative stress and DNA damage - DNA repair system in vascular smooth muscle cells in artery and vein grafts

Graft failure in coronary artery bypass grafts (CABGs) utilizing the saphenous vein is significantly higher than in those utilizing the internal mammary artery (IMA) or the radial artery (RA). While a number of studies have described this phenomenon clinically, few have attempted to extensively examine the biological differences between vein and artery, or the short- and long-term effectiveness of their use. In addition, there is limited information on the role of reactive oxygen species (ROS) in the generation of oxidative stress in the vascular smooth muscle cell, which we speculate has a significant role in inducing apoptosis and, consequently, graft failure. The purpose of this review, thus, is to concisely describe the relationship among DNA damage, DNA repair and graft failure by examining (1) DNA lesions resulting from oxidative damage, such as 8-oxo-7,8-dihydroguanine, as well as their affiliation with human diseases, (2) biological differences in DNA damage and repair capabilities of both artery and vein, and (3) DNA repair mechanisms and the significance of several repair enzymes.