Influence of sex on the number of circulating endothelial microparticles and microRNA expression in middle‐aged adults

• Published in: Experimental physiology 2017-08, Vol.102 (8), p.894-900
• Main Authors: Bammert, Tyler D., Hijmans, Jamie G., Kavlich, Philip J., Lincenberg, Grace M., Reiakvam, Whitney R., Fay, Ryan T., Greiner, Jared J., Stauffer, Brian L., DeSouza, Christopher A.
• Format: Article
• Language: English
• Subjects: Apoptosis; Apoptosis - physiology; Biomarkers - metabolism; Cell-Derived Microparticles - metabolism; Cell-Derived Microparticles - physiology; Endothelial Cells - metabolism; Endothelial Cells - physiology; Endothelium, Vascular - metabolism; Endothelium, Vascular - physiology; Female; Flow cytometry; gender; Humans; Male; Microparticles; microRNA; MicroRNAs; MicroRNAs - metabolism; Middle age; Middle Aged; miRNA; Peripheral blood; Polymerase chain reaction; Sex Characteristics; Sex differences; Women
• ISSN: 0958-0670; 1469-445X
• DOI: 10.1113/EP086359

New Findings What is the central question of this study? Are there sex‐related differences in the number of circulating endothelial microparticles (EMPs) and microparticle microRNA expression in middle‐aged adult humans? What is the main finding and its importance? Although the numbers of circulating endothelial microparticles do not differ between middle‐aged men and women, there are sex‐related differences in the expression of miR‐125a in activation‐derived EMPs and miR‐34a in apoptosis‐derived EMPs. Differences in circulating endothelial microparticle microRNA content may provide new insight into the sex‐related disparity in the risk and prevalence of vascular disease in middle‐aged adults. The aims of this study were to determine: (i) whether circulating concentrations of endothelial microparticles (EMPs) differ in middle‐aged men compared with women; and (ii) whether there are sex‐related differences in microRNA expression in EMPs. Peripheral blood was collected from 30 sedentary adults: 15 men (56 ± 6 years old) and 15 women (56 ± 5 years old). Endothelial microparticles were defined by markers of activation (CD62e+) or apoptosis (CD31+/CD42b−) by flow cytometry. Expression of microRNA (miR‐34a, 92a, 125a and 126) in activation‐ and apoptosis‐derived EMPs was measured by RT‐PCR. Circulating activation‐ (33 ± 31 versus 39 ± 35 microparticles μl−1) and apoptosis‐derived EMPs (49 ± 54 versus 42 ± 43 microparticles μl−1) were not significantly different between men and women. Expression of miR‐125a (2.23 ± 2.01 versus 6.95 ± 3.99 a.u.) was lower (∼215%; P