Expression Analysis of Selected microRNAs in Diabetes Mellitus Visceral Fat Tissues.

PURPOSE: MicroRNA (miRNA) profiling of visceral adipose tissue in Type-2 diabetes mellitus (T2DM) remains limited. We compared the expression of obesity-associated miRNAs in visceral fat from individuals with T2DM versus metabolically healthy obesity (MHO) and examined Raf kinase inhibitory protein (RKIP) as a candidate miR-543 target.

METHODS

Visceral fat biopsies were obtained from adults with T2DM (n = 8) and MHO (n = 11). Thirteen miRNAs previously linked to obesity were quantified, and RKIP expression was evaluated at the mRNA level and by immunohistochemistry, including phosphorylated RKIP (pRKIP).

RESULTS

Of the 13 miRNAs analyzed, miR-23a-3p and miR-543 were upregulated in T2DM (p = 0.032 and p = 0.009, respectively), whereas miR-320a-3p was downregulated (p = 0.009). RKIP mRNA levels did not differ between groups; however, in MHO adipocytes, RKIP mRNA correlated positively with miR-543 expression (r = 0.655, p = 0.034). Total RKIP protein was comparable between groups, while pRKIP was significantly higher in T2DM adipocytes (p = 0.012).

CONCLUSIONS

Posttranscriptional regulation in visceral adipocytes differs between T2DM and MHO. Increased miR-543 and elevated pRKIP in T2DM suggest a rapid shift in regulatory signaling consistent with enhanced lipolysis and a proinflammatory milieu. Further studies are warranted to delineate the pRKIP-associated pathways in adipose tissue remodeling in T2DM.