Plasma MicroRNA-29c Levels Are Associated with Carotid Intima-Media Thickness and is a Potential Biomarker for the Early Detection of Atherosclerosis

Background/Aims: Atherosclerosis is a serious disease that increases the risk of myocardial infarction and ischemic stroke. Previous studies have demonstrated that microRNA (miR)-29c could play significant roles in atherosclerosis via regulating inflammatory processes. However, the relationship between miR-29c and carotid intima-media thickness (CIMT) remains unknown. This study investigated associations between miR-29c and atherosclerosis and tested whether plasma miR-29c levels could be used to detect atherosclerosis. Methods: Plasma miR-29c levels were estimated by quantitative real-time PCR, and CIMT was measured by carotid ultrasound. Associations between miR-29c and CIMT were assessed by Spearman’s correlation coefficient and multiple linear regression analyses. Results: In total, 170 participants were divided into the study (CIMT ≥0.9 mm) and control (CIMT < 0.9 mm) groups. The study group showed higher C-reactive protein (CRP) and miR-29c relative expression levels compared with the control group. CIMT was positively correlated with miR-29c (r=0.659, p< 0.001) and CRP (r=0.447, p< 0.001), and miR-29c levels were also correlated with CRP (r=0.512, p< 0.001). Furthermore, multiple linear regression analysis showed that CIMT was significantly correlated with miR-29c (β=0.573, 95% confidence interval [CI]: 0.315-0.839; p< 0.001) and CRP (β=0.439, 95%CI: 0.186–0.825; p< 0.001). After age, body mass index, systolic blood pressure, total cholesterol and fasting blood-glucose were adjusted for, CIMT was still closely associated with miR-29c (β=0.529, 95%CI: 0.354–0.812; p< 0.001) and CRP (β=0.417, 95%CI: 0.198–0.724; p< 0.001). Evaluating CRP and miR-29c together (AUC=0.900, p< 0.001) achieved a better prognostic value for atherosclerosis than miR-29c (AUC=0.870, p< 0.001) or CRP (AUC=0.722, p< 0.001) alone. Conclusion: Increased miR-29c was closely associated with CIMT and may serve as a biomarker for identifying atherosclerotic patients.