Network analysis identifies circulating miR-155 as predictive biomarker of type 2 diabetes mellitus development in obese patients: a pilot study

Obesity is the main risk factor for many non-communicable diseases. In clinical practice, unspecificmarkers are used for the determination of metabolic alterations and inflammation, without allowingthe characterization of subjects at higher risk of complications. Circulating microRNAs representan attractive approach for early screening to identify subjects affected by obesity more at risk ofdeveloping connected pathologies. The aim of this study was the identification of circulating freeand extracellular vesicles (EVs)-embedded microRNAs able to identify obese patients at higherrisk of type 2 diabetes (DM2). The expression data of circulating microRNAs derived from obesepatients (OB), with DM2 (OBDM) and healthy donors were combined with clinical data, throughnetwork-based methodology implemented by weighted gene co-expression network analysis. The sixcirculating microRNAs overexpressed in OBDM patients were evaluated in a second group of patients,confirming the overexpression of miR-155-5p in OBDM patients. Interestingly, the combination ofmiR-155-5p with serum levels of IL-8, Leptin and RAGE was useful to identify OB patients most atrisk of developing DM2. These results suggest that miR-155-5p is a potential circulating biomarker forDM2 and that the combination of this microRNA with other inflammatory markers in OB patients canpredict the risk of developing DM2.