Atherosclerosis is an inflammatory disease wherein cholesterol-loaded macrophages play a major role. MicroRNAs and microparticles propagate inflammatory pathways and are involved in cardiovascular disease. We aimed to screen and validate circulating microRNAs correlated with atherosclerosis development in humans, and to dissect the molecular mechanisms associated with atherogenesis using in vitro and in vivo approaches. A panel of 179 secreted microRNAs was screened in plasma samples of patients with and without atherosclerosis, and validated cross-sectionally and prospectively in patients followed for up to 11 years. miR-30c-5p was inversely correlated with total and LDL cholesterol, carotid intimal media thickness (CIMT), presence and future development of plaques. Using a human macrophage line and in vitro gene silencing strategies, we found that miR-30c-5p was downregulated by oxidized LDL (oxLDL) via the scavenger receptor CD36 and inhibition miR processing by Dicer. In turn, miR-30c-5p downregulation was responsible for the effects of oxLDL on macrophage IL-1β release, caspase-3 expression, and apoptosis. miR-30c-5p loaded into microparticles was uptaken by macrophages and regulated target genes, like caspase-3, at transcriptional level. To establish the relevance of this pathway on endothelial damage as the earliest step of atherogenesis, we show that systemic miR-30c-5p knockdown induced caspase-3 and impaired endothelial healing after carotid injury in C57Bl/6 J mice. With an unbiased screening of secreted microRNAs, we identify reduction of miR-30c-5p in microparticles as a promoter of early atherosclerosis, by conveying pro-inflammatory pro-apoptotic signals and impairing endothelial healing. Therefore, stimulation of miR-30c-5p is a candidate direct anti-atherosclerotic therapy.

Microparticles (MPs) are vesicular structures shed from endothelial or circulating blood cells, after activation or apoptosis, and can be considered markers of vascular damage. We aimed to determine the levels of circulating MPs, their content of miRNA-126-3p and 5p, and their relationship with early endothelial activation/damage, in patients with different degree of glucose tolerance. CD62E+, CD62P+, CD142+, CD45+ circulating MPs, their apoptotic (AnnexinV+) fractions, and miRNA-126 expression were determined in 39 prediabetic (PreDM), 68 type 2 diabetic (T2DM), and 53 control (NGT) subjects, along with main anthropometric and biochemical measurements. MPs were analysed by flow cytometry. miRNA-126 was measured by quantitative real-time PCR. Plasma antioxidant capacity was determined by electronic spin resonance; ICAM-1, and VCAM-1 by ELISA. Activated endothelial cell-derived MPs (CD62E+) were significantly increased in PreDM and T2DM in comparison to NGT (p < 0.0001). AnnexinV+/CD62E+ MPs and Annexin V+ MPs were significantly increased in T2DM compared to PreDM and NGT (p < 0.001); other MPs were not significantly different among groups. Plasma antioxidant capacity was significantly decreased in PreDM and T2DM compared to NGT (p = 0.001); VCAM-1 significantly increased in PreDM and T2DM in comparison to NGT (p = 0.001). miR-126-3p expression, but not miR-126-5p, in MPs, decreased significantly and progressively from NGT, to PreDM, and T2DM (p < 0.001). In PreDM and T2DM, CD62E+ MPs level was significantly and negatively associated with plasma glucose (p = 0.004). We show for the first time that circulating CD62E+ MPs level and miR-126-3p content in MPs are abnormal in subjects with pre-diabetes; the content of miR-126-3p correlates with markers of endothelial inflammation, such as VCAM-1, plasma antioxidant capacity, and microparticles, well-accepted markers of endothelial dysfunction.

High altitude is a natural laboratory, within which the clinical study of human physiological response to hypobaric hypoxia (HH) is possible. Failure in the response results in progressive hypoxemia, inflammation and increased tissue oxidative stress (OxS). Thus, investigating temporal changes in key transcription factors (TFs)HIF-1α,HIF-2α,NF-κB and NRF2mRNA levels, relative to OxS and inflammatory markers, may reveal molecular targets which contrast deleterious effects of hypoxia. Biological samples and clinical data from 15 healthy participants were collected at baseline and after rapid, passive ascent to 3830 m (24 h and 72 h). Gene expression was assessed by qPCR and ROS generation was determined by EPR spectroscopy. Oxidative damage and cytokine levels were estimated by immuno or enzymatic methods. Hypoxia transiently enhancedHIF-1αmRNA levels over time reaching a peak after 24 h. Whereas,HIF-2αandNRF2mRNA levels increased over time. In contrast, theNF-κBmRNA levels remained unchanged. Plasma levels of IL-1β and IL-6 also remained within normal ranges. ROS production rate and markers of OxS damage were significantly increased over time. The analysis of TF-gene expression suggests that HIF-1α is a lead TF during sub-acute HH exposure. The prolongation of the HH exposure led to a switch between HIF-1α and HIF-2α/NRF2, suggesting the activation of new pathways. These results provide new insights regarding the temporal regulation of TFs, inflammatory state, and ROS homeostasis involved in human hypoxic response, potentially also relevant to the mediation of diseases that induce a hypoxic state.

OBJECTIVE: Cardiovascular disease (CVD) accounts for most deaths in patients with type 1 diabetes (T1D); however, the determinants of plaque composition are unknown. miRNAs regulate gene expression, participate in the development of atherosclerosis, and represent promising CVD biomarkers. This study analyzed the circulating miRNA expression profile in T1D with either carotid calcified (CCP) or fibrous plaque (CFP).RESEARCH DESIGN AND METHODS: Circulating small noncoding RNAs were sequenced and quantified using next-generation sequencing and bioinformatic analysis in an exploratory set of 26 subjects with T1D with CCP and in 25 with CFP. Then, in a validation set of 40 subjects with CCP, 40 with CFP, and 24 control subjects with T1D, selected miRNA expression was measured by digital droplet PCR. Putative gene targets enriched for pathways implicated in atherosclerosis/vascular calcification/diabetes were analyzed. The patients’ main clinical characteristics were also recorded.RESULTS: miR-503-5p, let-7d-5p, miR-106b-3p, and miR-93-5p were significantly upregulated, while miR-10a-5p was downregulated in patients with CCP compared with CFP (all fold change >±1.5; P < 0.05). All candidate miRNAs showed a significant correlation with LDL-cholesterol, direct for the upregulated and inverse for the downregulated miRNA, in CCP. Many target genes of upregulated miRNAs in CCP participate in osteogenic differentiation, apoptosis, inflammation, cholesterol metabolism, and extracellular matrix organization.CONCLUSIONS: These findings characterize miRNAs and their signature in the regulatory network of carotid plaque phenotype in T1D, providing new insights into plaque pathophysiology and possibly novel biomarkers of plaque composition.

To investigate the epigenetic footprint of idiopathic inflammatory myopathies (IIM) through characterization of circulating extracellular vesicles (EVs) and the expression of EV-derived small non-coding RNAs (sncRNAs). In this cross-sectional study, EVs were isolated by size-exclusion chromatography from plasma of patients with IIM and age- and sex-matched healthy donors (HD). EV-derived sncRNAs were sequenced and quantified using Next-Generation Sequencing (NGS). Following quality control and normalization, filtered count reads were used for differential microRNA (miRNA) and piwi-interacting RNA (piRNA) expression analyses. Putative gene targets enriched for pathways implicated in IIM were analyzed. Patients' clinical and laboratory characteristics at the time of sampling were recorded. Forty-seven IIM patients and 45 HD were enrolled. MiR-486-5p (p < 0.01), miR-122-5p, miR-192-5p, and miR-32-5p were significantly upregulated (p < 0.05 for all), while miR-142-3p (p < 0.001), miR-141-3p (p < 0.01), let-7a-5p (p < 0.05) and miR-3613-5p (p < 0.05) downregulated in EVs from IIM patients versus HD. MiR-486-5p was associated with raised muscle enzymes levels. Several target genes of up/downregulated miRNAs in IIM participate in inflammation, necroptosis, interferon and immune signaling. Six piRNAs were significantly dysregulated in IIM EVs versus HD (p < 0.05). Within IIM, miR-335-5p was selectively upregulated and miR-27a-5p downregulated in dermatomyositis (n = 21, p < 0.01). Finally, plasma EV levels were significantly increased in cancer-associated myositis (CAM, n = 12) versus non-CAM IIM (n = 35, p = 0.02) and HD (p < 0.01). EVs cargo in CAM was significantly enriched of let-7f-5p and depleted of miR-143-3p. Through an unbiased screening of EV-derived sncRNAs, we characterize miRNAs and piRNAs in the EVs cargo as potential biomarkers and modifiers of diverse IIM phenotypes.

Hypobaric hypoxia (HH) induces coordinated physiological and molecular responses supporting acclimatization to reduced oxygen availability. However, the temporal integration of blood mRNA and miRNA expression during early HH exposure remains incompletely understood. Eight healthy males were exposed for 72 h to simulated moderate HH (~ 3500 m) in the terraXcube facility. Blood transcriptomic and miRNA profiles were analyzed at baseline and after 12, 24, and 72 h, together with physiological variables, reactive oxygen species (ROS), and circulating inflammatory and endothelial biomarkers. Differential expression analysis revealed a progression from early stress and innate immune responses at 12 h, involving FOSB , CITED4 , and IDO1 , to remodeling of lymphocyte-specific programs at 24 h, including PAX5 , TCF7 , and TNFRSF13C . At 72 h, broader changes involved AP-1 components ( JUN , JUNB , and FOSB ), lymphocyte regulators ( PAX5 and FOXP3 ), and the antioxidant gene SOD2 . Integrated analysis identified predicted miRNA–mRNA pairs displaying inverse expression patterns within these pathways. Notably, miR-486-3p was consistently upregulated and miR-29c-5p downregulated across all time points. Plasma biomarkers remained largely stable, except for a transient increase in ICAM-1 and a marked decrease in TNF-α at 12 h, while ROS increased early and subsequently stabilized. Together, these findings identify distinct but overlapping phases of early HH acclimatization, progressing from stress and innate immune activation to lymphocyte-specific and redox remodeling. The temporal dissociation between coordinated mRNA and miRNA expression changes and limited circulating inflammatory responses indicates that molecular adaptation extends beyond detectable systemic inflammatory activation.