Circulating small non-coding RNA profiling as potential biomarkers of atherosclerotic plaque composition in Type 1 diabetes

OBJECTIVE

Cardiovascular disease (CVD) accounts for most deaths in patients with type 1 diabetes (T1D); however, the determinants of plaque composition are unknown. MicroRNAs (miRNAs) regulate gene expression, participate in the development of atherosclerosis and represent promising CVD biomarkers. This study analyzed the circulating miRNA expression profile in T1D with carotid either calcified (CCP) or fibrous (CFP) plaque.

RESEARCH DESIGN AND METHODS

Circulating small non-coding RNA were sequenced and quantified using NGS and bioinformatic analysis in an exploratory set of 26 T1D with CCP and in 25 with CFP. Then, in a validation set of 40 CCP, 40 CFP and 24 controls T1D, selected miRNAs expression was measured by digital droplet PCR. Putative gene targets enriched for pathways implicated in atherosclerosis/vascular calcification/diabetes were analyzed. Patient’s main clinical characteristics were also recorded.

RESULTS

miR-503-5p, let-7d-5p, miR-106b-3p, miR-93-5p were significantly up-regulated, while miR-10a-5p downregulated in CCP patients compared to CFP (all FC>±1.5, p<0.05). All candidate miRNAs showed a significant correlation with LDL-cholesterol, direct for the up-regulated and inverse for the downregulated one, in CCP. Many target genes of up-regulated miRNAs in CCP participate in osteogenic differentiation, apoptosis, inflammation, cholesterol metabolism, and extracellular matrix organization.

CONCLUSIONS

These findings characterize miRNAs and their signature in the regulatory network of carotid plaque phenotype, in T1D, providing new insights into plaque pathophysiology, and possibly novel biomarkers of plaque composition.