Age-Related Variations of Caveolins Expression in the Wall of Saphenous Vein Used for Coronary Artery Bypass Grafting. A Preliminary Report

Abstract

Background: Smooth muscle cells (SMCs) in the tunica media of the saphenous vein (SV) used for aortocoronary grafts play a key role in intimal hyperplasia. This process, followed by the development of atherosclerosis, leads to occlusion of the SV grafts months and years after coronary artery bypass grafting (CABG). Caveolins have been suggested to control some of the SMCs responses. The aim of this study was to identify any variations in expression of caveolins (cav-1, cav-2 and cav-3) in the SMCs of the SV transplants in relation to the age of CABG who undergo CABG.

Methods: This study involved 110 (83 males and 27 females) consecutive, isolated and non-emergent CABG patients. They were retrospectively divided into four age subgroups: (A; n=19) ≤50 year-old, (B; n=24) >50 and ≤60 year-old, (C; n=40) >60 and ≤70 year-old, (D; n=27) >70 year-old. Expression of cav-1, cav-2 and cav-3 in the SV wall was evaluated by means of immunohistochemistry.

Results: Expression of cav-1 and cav-3 in the SV wall increased systematically with the age of CABG patients and was statistically significant between group A and D (p<0.05). A positive correlation between the age of patients and expression of cav-1 and cav-3 was found (r=0.450 and r=0.463, respectively). Cav-2 expression did not differ between the examined subgroups.

Conclusion: This study revealed positive correlations between the expressions of cav-1 and cav-3 in the medial venous SMCs and the age of CABG patients. However, further investigations are necessary to show clinical significance of these age-related variations.