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NEW FINDINGS What is the central question of the study Is habitual short sleep associated with altered circulating levels of specific inflammation- and vascular-related microRNAs? What is the main finding and its importance? Circulating levels of miR-125a, miR-126 and miR-146a were significantly lower in the short sleep compared with the normal sleep group. Altered circulating profiles of these vascular-related microRNAs have been linked to vascular inflammation, dysfunction and increased cardiovascular disease events. Sleep-related changes in these microRNAs are consistent with, and might play a role in, the aberrant vascular physiology and increased vascular risk associated with short sleep. ABSTRACT Habitual short sleep duration (

The aim of this study was to determine the effects of endothelin-1 (ET-1)-generated endothelial microvesicles (EMVs) on endothelial cell inflammation, apoptosis, and endothelial nitric oxide synthase (eNOS). Human umbilical vein endothelial cells (HUVECs) were treated with ET-1 for 24 h. EMVs released into the supernatant from cells treated with ET-1 or vehicle were isolated and quantified. EMV release was higher (P < 0.05) in cells treated with ET-1 compared with control (95 ± 15 vs. 54 ± 5 EMV/µL). Fresh HUVECs were then treated with either ET-1, ET-1-induced EMVs, or control EMVs for 24 h. ET-1-generated EMVs induced significantly higher release of IL-6 (181.0 ± 16.0 vs. 132.1 ± 8.1 pg/mL) and IL-8 (303.4 ± 37.4 vs. 211.8 ± 10.0 pg/mL), as well as greater total NF-κB p65 (76.0 ± 7.6 vs. 57.1 ± 2.1 AU) and active NF-κB p65 (Ser-536) (11.6 ± 0.9 vs. 6.8 ± 1.0 AU) expression than control EMVs. There were no significant differences in expression of caspase-9 (230.1 ± 24.3 vs. 243.6 ± 22.3 AU), caspase-3 (271.9 ± 22.7 vs. 265.1 ± 30.5 AU), and active caspase-3 (4.4 ± 0.4 vs. 4.3 ± 0.1 AU) in cells treated with ET-1-EMVs versus control EMVs. Total eNOS (108.4 ± 11.4 vs. 158.8 ± 1.6 AU) and activated eNOS (4.7 ± 0.5 vs. 9.6 ± 1.4 AU) were significantly lower in endothelial cells treated with ET-1-generated EMVs compared with control EMVs. The effects of ET-1-generated EMVs on cellular markers and mediators of endothelial inflammation, as well as eNOS function, was comparable to the effects of ET-1. In summary, ET-1 induces an EMV phenotype that adversely affects endothelial cell function. ET-1-generated EMVs may contribute to the atherogenic effect of ET-1. NEW & NOTEWORTHY Endothelin-1 (ET-1) is a potent vasoconstrictor peptide released by the endothelium that contributes to the regulation of vascular tone. Overexpression of ET-1 has been implicated in the etiology of atherosclerotic vascular disease. Endothelial cell-derived microvesicles (EMVs) play a pivotal role in vascular health and disease. Their functional phenotype is largely dictated by the stimulus for release. EMVs released in response to various pathological conditions have been shown to elicit deleterious vascular effects. In the present study, we determined, in vitro, the effect of ET-1 on EMV release from endothelial cells and the effects of ET-1-generated EMVs on endothelial cell inflammation, apoptosis, and endothelial nitric oxide synthase (eNOS). ET-1 induced a marked increase in EMV release. ET-1-generated EMVs significantly increased endothelial cell inflammation and reduced eNOS protein expression and activation. Moreover, the endothelial effects of ET-1-derived EMVs were similar to the direct effects of ET-1. ET-1-generated EMVs may contribute to the proatherogenic profile of ET-1.

Background Circulating microparticles have emerged as biomarkers and effectors of vascular disease. Elevated rates of cardiovascular disease are seen in HIV ‐1–seropositive individuals. The aims of this study were to determine: (1) if circulating microparticles are elevated in antiretroviral therapy–treated HIV ‐1–seropositive adults; and (2) the effects of microparticles isolated from antiretroviral therapy –treated HIV ‐1–seropositive adults on endothelial cell function, in vitro. Methods and Results Circulating levels of endothelial‐, platelet‐, monocyte‐, and leukocyte‐derived microparticles were determined by flow cytometry in plasma from 15 healthy and 15 antiretroviral therapy–treated, virologically suppressed HIV ‐1–seropositive men. Human umbilical vein endothelial cells were treated with microparticles from individual subjects for 24 hours; thereafter, endothelial cell inflammation, oxidative stress, senescence, and apoptosis were assessed. Circulating concentrations of endothelial‐, platelet‐, monocyte‐, and leukocyte‐derived microparticles were significantly higher (≈35%–225%) in the HIV ‐1–seropositive compared with healthy men. Microparticles from HIV ‐1–seropositive men induced significantly greater endothelial cell release of interleukin‐6 and interleukin‐8 (≈20% and ≈35%, respectively) and nuclear factor‐κB expression while suppressing anti‐inflammatory microRNAs (miR‐146a and miR‐181b). Intracellular reactive oxygen species production and expression of reactive oxygen species –related heat shock protein 70 were both higher in cells treated with microparticles from the HIV ‐1–seropositive men. In addition, the percentage of senescent cells was significantly higher and sirtuin 1 expression lower in cells treated with HIV ‐1–related microparticles. Finally, caspase‐3 was significantly elevated by microparticles from HIV ‐1–seropositive men. Conclusions Circulating concentrations of endothelial‐, platelet‐, monocyte‐, and leukocyte‐derived microparticles were higher in antiretroviral therapy–treated HIV ‐1–seropositive men and adversely affect endothelial cells promoting cellular inflammation, oxidative stress, senescence, and apoptosis. Circulating microparticles may contribute to the vascular risk associated with HIV ‐1 infection.

microRNAs (miRs) are short single stranded noncoding RNAs that are involved in the regulation of a number of physiological and pathological processes. miRs down regulate target gene expression post-transcriptionally by degrading messenger RNA and/or by blocking translation. It is now recognized that miRs play a key role in regulating inflammation, vascular health and in-turn, cardiovascular disease (CVD). For example, altered expression of specific miRs such as, miR-126, miR-146a and miR-150 have been linked with heightened vascular inflammation and CVD risk. Hypertension is associated with increased inflammatory burden. The mechanisms underlying blood pressure-related inflammatory stress are not fully understood. It is currently unknown whether inflammation-related miRs are dysregulated with elevated blood pressure. Accordingly, the aim of this ongoing study is to determine the influence of hypertension, independent of other risk factors, on circulating expression of miR-34a, miR-92a, miR -126, miR-146a and miR-150. To date, 28 sedentary, middle-aged adults have been studied: 14 normotensive (NT; 12M/2F; age: 53±1 yr; BP: 114/71±2/1 mmHg) and 14 hypertensive (HT; 12M/2F; 56±2 yr; 142/90±2/2 mmHg). All subjects were non-smokers, normolipidemic, non-medicated and free of overt CVD. Circulating expression of miRs was determined in plasma using standard RT-PCR techniques with miR primers of interest. Expression was normalized to exogenous C. elegans miR-39 and reported as relative expression in arbitrary units (AU). Circulating expression of miR-126 (0.14±0.03 vs 0.33±0.04 AU) and miR-150 (0.06±0.02 vs 0.12±0.02 AU) were markedly lower (~135% and 100%, respectively; P