Elevated Plasma miR-29a Levels Are Associated with Increased Carotid Intima-Media Thickness in Atherosclerosis Patients

Atherosclerotic cardiovascular diseases, such as coronary heart disease, have become a major public health problem all over the world. MicroRNA-29a (miR-29a) modulates expression levels of collagen, inflammatory reaction and other extracellular matrix mRNAs, while adiponectin (APN), a circulating protein secreted by adipocytes, has anti-inflammatory properties. Both play multifaceted roles in angiogenesis or vascular remodelling. However, little is known about plasma miR-29a and APN levels in patients with atherosclerosis. We therefore investigated the relationship between the plasma levels of miR-29a or APN and carotid intima-media thickness (cIMT) in atherosclerosis patients (n = 85, cIMT ≥ 1.2 mm) and the controls (n = 85, cIMT < 1.2 mm). We found that the atherosclerosis group showed higher miR-29a levels (31.15 ± 3.99 vs. 26.39 ± 1.05 Ct, P < 0.001) and lower APN levels (15.93 ± 4.61 vs. 21.80 ± 7.74 ng/ml, P < 0.001), compared with control group. Thus, increased cIMT was associated with higher plasma miR-29a levels (r = 0.688, P < 0.001) and with lower plasma APN levels (r = -0.494, P < 0.001). Furthermore, multiple logistic regression analysis indicated that higher miR-29a levels (OR: 1.136, 95% CI: 1.042-1.240, P = 0.004) increased the risk for atherosclerosis, whereas higher APN levels appeared to be protective (OR: 0.122, 95% CI: 0.055-0.271, P < 0.001). The present study indicates that elevated miR-29a levels and reduced APN levels are associated with atherosclerosis.