Microparticles miRNAs as biomarkers of aerobic exercise efficacy on vascular function and inflammation in obese patients?

The mechanisms involved by physical exercise, controlling inflammation and micro/macro-circulation are not fully identified. However, they are based in part on the regulation of gene expression at the level of blood circulating cells. A new regulatory mechanism of gene expression involves microRNAs (miRNAs), which are transported in the circulation with microparticules (MPs). The modulation of miRNAs expression has recently been implicated in the regulation of inflammation and vascular diseases and thought to be potential biomarkers of exercise response in healthy subject or athletes. However, never such approach on the role of miRNAs as biomarkers of the efficacy of aerobic exercise intervention in obese patients has been realized. Two groups of sedentary (n = 6, BMI   30 kg/m2) recruited at F. Hached Hospital (Sousse, Tunisia) were enrolled in an 8-weeks training program. Vascular function was assessed by Laser Doppler Flowmetry, MPs quantification by flow cytometry, miRNAs content by real-time PCR and inflammation by ELISA before and after exercise training. Aerobic exercise improved significantly the endothelial-dependent vasorelaxation in healthy patients and to a lesser extent in obese patients, improved systemic inflammation, and increased circulating MPs level in both groups. The miRNA profile analysis revealed that (1) miR-21,-150,-320a,-146a,-124a,-126 and -223 were expressed in circulating MPs of sedentary healthy and obese women; (2) after aerobic exercise, the expression of miR-21,-146a,-124a,-150,-320a was differentially overexpressed in healthy and obese subjects while miR-126 and -223 remained unchanged; and finally (3) significant correlation was found between miR-150 and -320a and adiponectin and TNF-α levels. Our results highlight the incidence of aerobic exercise training on MPs content and their role as vehicle for miRNAs, which function as intercellular communication devices regulating particularly inflammation.