Endothelial microRNAs and atherosclerosis

Epidrugs in the clinical management of atherosclerosis: Mechanisms, challenges and promises

Atherosclerosis is a complex and multigenic pathology associated with significant epigenetic reprogramming. Traditional factors (age, sex, obesity, hyperglycaemia, dyslipidaemia, hypertension) and non-traditional factors (foetal indices, microbiome alteration, clonal hematopoiesis, air pollution, sleep disorders) induce endothelial dysfunction, resulting in reduced vascular tone and increased vascular permeability, inflammation and shear stress. These factors induce paracrine and autocrine interactions between several cell types, including vascular smooth muscle cells, endothelial cells, monocytes/macrophages, dendritic cells and T cells. Such cellular interactions lead to tissue-specific epigenetic reprogramming regulated by DNA methylation, histone modifications and microRNAs, which manifests in atherosclerosis. Our review outlines epigenetic signatures during atherosclerosis, which are viewed as potential clinical biomarkers that may be adopted as new therapeutic targets. Additionally, we emphasize epigenetic modifiers referred to as 'epidrugs' as potential therapeutic molecules to correct gene expression patterns and restore vascular homeostasis during atherosclerosis. Further, we suggest nanomedicine-based strategies involving the use of epidrugs, which may selectively target cells in the atherosclerotic microenvironment and reduce off-target effects.

Inhibition of circ_0000231 suppresses oxidized low density lipoprotein-induced apoptosis, autophagy and inflammation in human umbilical vein endothelial cells by regulating miR-590-5p/PDCD4 axis

BACKGROUND

Circular RNAs (circRNAs) are the emerging informative RNAs, involved in cardiovascular diseases including atherosclerosis (AS). Endothelial injury is the initial qualitative change of AS. Thus, the objective of this study was to confirm the dysregulation and mechanism of circ_0000231 in cell model of AS at early stage in human umbilical vein endothelial cells (HUVECs) induced by oxidized low-density lipoprotein (ox-LDL).

METHODS

The expression of circ_0000231, miR-590-5p and programmed cell death 4 (PDCD4) was detected using real-time quantitative PCR and western blot. Cell injury was measured with MTT, flow cytometry, caspase-3 activity assay and enzyme-linked immunosorbent assay (ELISA). The interaction among circ_0000231, miR-590-5p and PDCD4 was validated by dual-luciferase reporter assay, RNA immunoprecipitation (RIP) and pull-down assays.

RESULTS

Stress ox-LDL decreased cell viability, and increased apoptosis rate and caspase-3 activity in HUVECs in a dose- and time-dependent manner in concomitant with promotions of interleukin-6, interleukin-1β, tumor necrosis factor-α, LC3-II/I and Beclin-1 levels. Besides, circ_0000231 and PDCD4 expressions were upregulated, and miR-590-5p was downregulated in ox-LDL-stimulated HUVECs. Functionally, knockdown of circ_0000231 and overexpression of miR-590-5p could suppress ox-LDL-elicited above effects on apoptosis, autophagy and inflammatory response, accompanied with PDCD4 downregulation. Physically, miR-590-5p could directly interact with circ_0000231 and PDCD4.

CONCLUSION

Downregulation of circ_0000231 suppresses HUVECs from ox-LDL-induced injury partially through regulating miR-590-5p/PDCD4 axis via competing endogenous RNA mechanism, showing a novel potential target for the pathology and treatment of endothelial injury in AS.

RNA interference-based therapies for atherosclerosis: Recent advances and future prospects

Atherosclerosis represents a pathological state that affects the arterial system of the organism. This chronic, progressive condition is typified by the accumulation of atheroma within arterial walls. Modulation of RNA molecules through RNA-based therapies has expanded the range of therapeutic options available for neurodegenerative diseases, infectious diseases, cancer, and, more recently, cardiovascular disease (CVD). Presently, microRNAs and small interfering RNAs (siRNAs) are the most widely employed therapeutic strategies for targeting RNA molecules, and for regulating gene expression and protein production. Nevertheless, for these agents to be developed into effective medications, various obstacles must be overcome, including inadequate binding affinity, instability, challenges of delivering to the tissues, immunogenicity, and off-target toxicity. In this comprehensive review, we discuss in detail the current state of RNA interference (RNAi)-based therapies.

Inflammatory microRNAs in cardiovascular pathology: another brick in the wall

The regulatory role of microRNAs (miRNAs) is mainly mediated by their effect on protein expression and is recognized in a multitude of pathophysiological processes. In recent decades, accumulating evidence has interest in these factors as modulatory elements of cardiovascular pathophysiology. Furthermore, additional biological processes have been identified as new components of cardiovascular disease etiology. In particular, inflammation is now considered an important cardiovascular risk factor. Thus, in the present review, we will focus on the role of a subset of miRNAs called inflamma-miRs that may regulate inflammatory status in the development of cardiovascular pathology. According to published data, the most representative candidates that play functional roles in thromboinflammation are miR-21, miR-33, miR-34a, miR-146a, miR-155, and miR-223. We will describe the functions of these miRNAs in several cardiovascular pathologies in depth, with specific emphasis on the molecular mechanisms related to atherogenesis. We will also discuss the latest findings on the role of miRNAs as regulators of neutrophil extracellular traps and their impact on cardiovascular diseases. Overall, the data suggest that the use of miRNAs as therapeutic tools or biomarkers may improve the diagnosis or prognosis of adverse cardiovascular events in inflammatory diseases. Thus, targeting or increasing the levels of adequate inflamma-miRs at different stages of disease could help mitigate or avoid the development of cardiovascular morbidities.

PANDORA-Seq unveils the hidden small noncoding RNA landscape in atherosclerosis of LDL receptor-deficient mice

Small noncoding RNAs (sncRNAs) play diverse roles in numerous biological processes. While the widely used RNA sequencing (RNA-Seq) method has advanced sncRNA discovery, RNA modifications can interfere with the complementary DNA library construction process, preventing the discovery of highly modified sncRNAs including transfer RNA-derived small RNAs (tsRNAs) and ribosomal RNA-derived small RNAs (rsRNAs) that may have important functions in disease development. To address this technical obstacle, we recently developed a novel PANDORA-Seq (Panoramic RNA Display by Overcoming RNA Modification Aborted Sequencing) method to overcome RNA modification-elicited sequence interferences. To identify novel sncRNAs associated with atherosclerosis development, LDL receptor-deficient (LDLR-/-) mice were fed a low-cholesterol diet or high-cholesterol diet (HCD) for 9 weeks. Total RNAs isolated from the intima were subjected to PANDORA-Seq and traditional RNA-Seq. By overcoming RNA modification-elicited limitations, PANDORA-Seq unveiled an rsRNA/tsRNA-enriched sncRNA landscape in the atherosclerotic intima of LDLR-/- mice, which was strikingly different from that detected by traditional RNA-Seq. While microRNAs were the dominant sncRNAs detected by traditional RNA-Seq, PANDORA-Seq substantially increased the reads of rsRNAs and tsRNAs. PANDORA-Seq also detected 1,383 differentially expressed sncRNAs induced by HCD feeding, including 1,160 rsRNAs and 195 tsRNAs. One of HCD-induced intimal tsRNAs, tsRNA-Arg-CCG, may contribute to atherosclerosis development by regulating the proatherogenic gene expression in endothelial cells. Overall, PANDORA-Seq revealed a hidden rsRNA and tsRNA population associated with atherosclerosis development. These understudied tsRNAs and rsRNAs, which are much more abundant than microRNAs in the atherosclerotic intima of LDLR-/- mice, warrant further investigations.

Circadian system microRNAs - Role in the development of cardiovascular diseases

Circadian rhythm regulates numerous physiological processes, and disruption of the circadian clock can lead to cardiovascular disease. Cardiovascular disease is the leading cause of morbidity and mortality worldwide. Small non-coding RNAs, microRNAs (miRNAs), are involved in regulating gene expression, both those important for the cardiovascular system and key circadian clock genes. Epigenetic mechanisms based on miRNAs are essential for fine-tuning circadian physiology. Indeed, some miRNAs depend on circadian periodicity, others are under the influence of light, and still others are under the influence of core clock genes. Dysregulation of miRNAs involved in circadian rhythm modulation has been associated with inflammatory conditions of the endothelium and atherosclerosis, which can lead to coronary heart disease and myocardial infarction. Epigenetic processes are reversible through their association with environmental factors, enabling innovative preventive and therapeutic strategies for cardiovascular disease. Here, is a review of recent findings on how miRNAs modulate circadian rhythm desynchronization in cardiovascular disease. In the era of personalized medicine, the possibility of treatment with miRNA antagomirs should be time-dependent to correspond to chronotherapy and achieve the most significant efficacy.

Inflammatory and Prothrombotic Biomarkers, DNA Polymorphisms, MicroRNAs and Personalized Medicine for Patients with Peripheral Arterial Disease

Classical risk factors play a major role in the initiation and development of atherosclerosis. However, the estimation of risk for cardiovascular events based only on risk factors is often insufficient. Efforts have been made to identify biomarkers that indicate ongoing atherosclerosis. Among important circulating biomarkers associated with peripheral arterial disease (PAD) are inflammatory markers which are determined by the expression of different genes and epigenetic processes. Among these proinflammatory molecules, interleukin-6, C-reactive protein, several adhesion molecules, CD40 ligand, osteoprotegerin and others are associated with the presence and progression of PAD. Additionally, several circulating prothrombotic markers have a predictive value in PAD. Genetic polymorphisms significantly, albeit moderately, affect risk factors for PAD via altered lipoprotein metabolism, diabetes, arterial hypertension, smoking, inflammation and thrombosis. However, most of the risk variants for PAD are located in noncoding regions of the genome and their influence on gene expression remains to be explored. MicroRNAs (miRNAs) are single-stranded, noncoding RNAs that modulate gene expression at the post-transcriptional level. Patterns of miRNA expression, to some extent, vary in different atherosclerotic cardiovascular diseases. miRNAs appear to be useful in the detection of PAD and the prediction of progression and revascularization outcomes. In conclusion, taking into account one’s predisposition to PAD, i.e., DNA polymorphisms and miRNAs, together with circulating inflammatory and coagulation markers, holds promise for more accurate prediction models and personalized therapeutic options.

New Progress in Early Diagnosis of Atherosclerosis

Coronary atherosclerosis is a potentially chronic circulatory condition that endangers human health. The biological cause underpinning cardiovascular disease is coronary atherosclerosis, and acute cardiovascular events can develop due to thrombosis, platelet aggregation, and unstable atherosclerotic plaque rupture. Coronary atherosclerosis is progressive, and three specific changes appear, with fat spots and stripes, atherosclerosis and thin-walled fiber atherosclerosis, and then complex changes in arteries. The progression and severity of cardiovascular disease are correlated with various levels of calcium accumulation in the coronary artery. The therapy and diagnosis of coronary atherosclerosis benefit from the initial assessment of the size and degree of calcification. This article will discuss the new progress in the early diagnosis of coronary atherosclerosis in terms of three aspects: imaging, gene and protein markers, and trace elements. This study intends to present the latest methods for diagnosing patients with early atherosclerosis through a literature review.

miR-10 and Its Negative Correlation with Serum IL-35 Concentration and Positive Correlation with STAT5a Expression in Patients with Rheumatoid Arthritis

Circulating free-cell miRNAs are increasingly important as potential non-invasive biomarkers due to the easy accessibility of clinical materials. Moreover, their epigenetic role may provide insight into the mechanisms of pathogenesis. Nevertheless, these aspects are mostly studied in the area of oncological diseases. Therefore, this research aimed to find the potential association of selected miRNAs in serum with the expression of Th17/Treg transcription factors and clinical features in RA patients. Accordingly, experiments was conducted on rheumatoid arthritis (RA), osteoarthritis (OA) and healthy subjects (HC). Analysis of miRNAs level in serum was performed using LNA miRNA PCR assays. mir-10 was detected only in RA patients. Furthermore, its expression was correlated with IL-35 serum concentration and the mRNA level of STAT5a in whole blood in RA. Additionally, a tendency of the raised level of miR-10 was noted in RA patients with high activity disease. miR-326 was significantly upregulated in RA patients with rheumatoid factor presence. In HC the correlation between miR-26 and IL-21 serum levels and expression of SMAD3 have been found. In OA patients, correlations between miR-126 and HIF1 expression and between miR-146 and RORc have been noted. The differential association of transcription factor expression with serum miRNA levels may be important in the diagnosis and progression of RA and OA.

Endothelial cell-specific deletion of a microRNA accelerates atherosclerosis

BACKGROUND AND AIMS

Chronic vascular endothelial inflammation predisposes to atherosclerosis; however, the cell-autonomous roles for endothelial-expressing microRNAs (miRNAs) are poorly understood in this process. MiR-181b is expressed in several cellular constituents relevant to lesion formation. The aim of this study is to examine the role of genetic deficiency of the miR-181b locus in endothelial cells during atherogenesis.

METHODS AND RESULTS

Using a proprotein convertase subtilisin/kexin type 9 (PCSK9)-induced atherosclerosis mouse model, we demonstrated that endothelial cell (EC)-specific deletion of miR-181a2b2 significantly promoted atherosclerotic lesion formation, cell adhesion molecule expression, and the influx of lesional macrophages in the vessel wall. Yet, endothelium deletion of miR-181a2b2 did not affect body weight, lipid metabolism, anti-inflammatory Ly6C^low or the pro-inflammatory Ly6C^interm and Ly6C^high fractions in circulating peripheral blood mononuclear cells (PBMCs), and pro-inflammatory or anti-inflammatory mediators in both bone marrow (BM) and PBMCs. Mechanistically, bulk RNA-seq and gene set enrichment analysis of ECs enriched from the aortic arch intima, as well as single cell RNA-seq from atherosclerotic lesions, revealed that endothelial miR-181a2b2 serves as a critical regulatory hub in controlling endothelial inflammation, cell adhesion, cell cycle, and immune response during atherosclerosis.

CONCLUSIONS

Our study establishes that deficiency of a miRNA specifically in the vascular endothelium is sufficient to profoundly impact atherogenesis. Endothelial miR-181a2b2 deficiency regulates multiple key pathways related to endothelial inflammation, cell adhesion, cell cycle, and immune response involved in the development of atherosclerosis.

Novel Biomarkers of Atherosclerotic Vascular Disease-Latest Insights in the Research Field

The atherosclerotic vascular disease is a cardiovascular continuum in which the main role is attributed to atherosclerosis, from its appearance to its associated complications. The increasing prevalence of cardiovascular risk factors, population ageing, and burden on both the economy and the healthcare system have led to the development of new diagnostic and therapeutic strategies in the field. The better understanding or discovery of new pathophysiological mechanisms and molecules modulating various signaling pathways involved in atherosclerosis have led to the development of potential new biomarkers, with key role in early, subclinical diagnosis. The evolution of technological processes in medicine has shifted the attention of researchers from the profiling of classical risk factors to the identification of new biomarkers such as midregional pro-adrenomedullin, midkine, stromelysin-2, pentraxin 3, inflammasomes, or endothelial cell-derived extracellular vesicles. These molecules are seen as future therapeutic targets associated with decreased morbidity and mortality through early diagnosis of atherosclerotic lesions and future research directions.

The Role of MicroRNAs in Endothelial Cell Senescence

Cellular senescence is a complex, dynamic process consisting of the irreversible arrest of growth and gradual deterioration of cellular function. Endothelial senescence affects the cell’s ability to repair itself, which is essential for maintaining vascular integrity and leads to the development of endothelial dysfunction, which has an important role in the pathogenesis of cardiovascular diseases. Senescent endothelial cells develop a particular, senescence-associated secretory phenotype (SASP) that detrimentally affects both surrounding and distant endothelial cells, thereby facilitating the ageing process and development of age-related disorders. Recent studies highlight the role of endothelial senescence and its dysfunction in the pathophysiology of several age-related diseases. MicroRNAs are small noncoding RNAs that have an important role in the regulation of gene expression at the posttranscriptional level. Recently, it has been discovered that miRNAs could importantly contribute to endothelial cell senescence. Overall, the research focus has been shifting to new potential mechanisms and targets to understand and prevent the structural and functional changes in ageing senescent endothelial cells in order to prevent the development and limit the progression of the wide spectrum of age-related diseases. The aim of this review is to provide some insight into the most important pathways involved in the modulation of endothelial senescence and to reveal the specific roles of several miRNAs involved in this complex process. Better understanding of miRNA’s role in endothelial senescence could lead to new approaches for prevention and possibly also for the treatment of endothelial cells ageing and associated age-related diseases.

A miRNA cassette reprograms smooth muscle cells into endothelial cells

Cellular reprogramming through targeting microRNAs (miRNAs) holds promise for regenerative therapy due to their profound regulatory effects in proliferation, differentiation, and function. We hypothesized that transdifferentiation of vascular smooth muscle cells (SMCs) into endothelial cells (ECs) using a miRNA cassette may provide a novel approach for use in vascular disease states associated with endothelial injury or dysfunction. miRNA profiling of SMCs and ECs and iterative combinatorial miRNA transfections of human coronary SMCs revealed a 4-miRNA cassette consisting of miR-143-3p and miR-145-5p inhibitors and miR-146a-5p and miR-181b-5p mimics that efficiently produced induced endothelial cells (iECs). Transcriptome profiling, protein expression, and functional studies demonstrated that iECs exhibit high similarity to ECs. Injected iECs restored blood flow recovery even faster than conventional ECs in a murine hindlimb ischemia model. This study demonstrates that a 4-miRNA cassette is sufficient to reprogram SMCs into ECs and shows promise as a novel regenerative strategy for endothelial repair.

Circulating miR-21-5p, miR-146a-5p, miR-320a-3p in patients with atrial fibrillation in combination with hypertension and coronary artery disease

Aim. To study the plasma profiles of circulating extracellular microribonucleic acids (miRNAs), potentially including in pathogenesis of cardiovascular diseases, in patients with atrial fibrillation (AF) in combination with hypertension (HTN) or coronary artery disease (CAD).

Material and methods. The study included patients with AF in combi  nation with HTN (n=21) or CAD (n=10), as well as following control groups: patients with uncomplicated HTN without AF (n=28), patients with stable CAD without AF (n=10) and healthy individuals (n=30). MiRNA samples were isolated from blood plasma of the study participants. MiRNAs were detected by TaqMan quantitative polymerase chain reaction assay. The relative plasma levels of five candidate miRNAs were estimated relative to the reference miR-16-5p.

Results. Among the analyzed circulating plasma miRNAs, a higher level of miR-320a-3p was associated with AF, while increased levels of miR 146a-5p and miR-21-5p are potentially associated with presence of both AF and CAD.

Conclusion. Differences were found in the plasma miRNA profiles (miR-21-5p, miR-320a-3p, miR-146a-5p) between patients with AF, regardless of concomitant disease (CAD or HTN), and healthy individuals in the control group.

MicroRNA-146a-5p alleviates lipopolysaccharide-induced NLRP3 inflammasome injury and pro-inflammatory cytokine production via the regulation of TRAF6 and IRAK1 in human umbilical vein endothelial cells (HUVECs)

Background

Microribonucleic acids (miRNAs) have an evident role in regulating endothelial inflammation and dysfunction, which characterizes the early stages of atherosclerosis. The NOD-like receptor family pyrin domain-containing protein 3 (NLRP3) inflammasome has been reported to contribute to the endothelial inflammatory response that promotes atherosclerosis development and progression. This study sought to investigate the effects of miR-146a-5p on lipopolysaccharide (LPS)-induced NLRP3 inflammasome injury and pro-inflammatory cytokine production in human umbilical vein endothelial cells (HUVECs).

Methods

HUVECs were transfected with a miR-146a-5p mimic, small-interfering RNA (siRNA) (si-TRAF6, and si-IRAK1), and were then stimulated with LPS for 24 h. The messenger (mRNA) and the protein levels of p-NF-κB/NF-κB, NLRP3, Caspase-1, pro-inflammatory cytokine [interleukin (IL)-6, IL-1β and tumor necrosis factor alpha (TNF-α)] in the HUVECs were analyzed by quantitative real-time polymerase chain reactions (PCRs) and western blot assays, respectively. The secretion of IL-6 from the cells was detected by enzyme-linked immunoassay (ELISA). Bioinformatic and dual-luciferase reporter assays were performed to identify the targets of miR-146a-5p.

Results

LPS promoted pro-inflammatory cytokine expression in a dose-dependent manner and significantly increased the expression levels of p-NF-κB/NF-κB p65, NLRP3, and Caspase-1. After transfection with a miR-146a-5p mimic, or si-TRAF6 or si-IRAK1, we observed that the mRNA and protein levels of NF-κB/p-NF-κB, NLRP3, Caspase-1, and pro-inflammatory cytokine in the HUVECs were all down-regulated, and the secretion of IL-6 from cells declined significantly. After transfection with a miR-146-5p mimic, the expression of TRAF6 and IRAK1 in HUVECs were both down-regulated. Dual-luciferase reporter assays confirmed that miR-146-5p directly targets the 3'-untranslated region (3'-UTR) of TRAF6 and IRAK1 to regulate their expression.

Conclusions

As a modulator of TRAF6 and IRAK1, miR-146a-5p negatively regulated LPS-induced NF-κB activation and the NLRP3 inflammasome signaling pathway in HUVECs. Thus, miRNA-146a-5p may serve as a potential therapeutic target for atherosclerosis.

Detection of Atherosclerosis by Small RNA-Sequencing Analysis of Extracellular Vesicle Enriched Serum Samples

Atherosclerosis can occur throughout the arterial vascular system and lead to various diseases. Early diagnosis of atherosclerotic processes and of individual disease patterns would be more likely to be successful if targeted therapies were available. For this, it is important to find reliable biomarkers that are easily accessible and with little inconvenience for patients. There are many cell culture, animal model or tissue studies that found biomarkers at the microRNA (miRNA) and mRNA level describing atherosclerotic processes. However, little is known about their potential as circulating and liquid biopsy markers in patients. In this study, we examined serum-derived miRNA - profiles from 129 patients and 28 volunteers to identify potential biomarkers. The patients had four different atherosclerotic manifestations: abdominal aneurysm (n = 35), coronary heart disease (n = 34), carotid artery stenosis (n = 24) and peripheral arterial disease (n = 36). The samples were processed with an extracellular vesicle enrichment protocol, total-RNA extraction and small RNA-sequencing were performed. A differential expression analysis was performed bioinformatically to find potentially regulated miRNA biomarkers. Resulting miRNA candidates served as a starting point for an overrepresentation analysis in which relevant target mRNAs were identified. The Gene Ontology database revealed relevant biological functions in relation to atherosclerotic processes. In patients, expression of specific miRNAs changed significantly compared to healthy volunteers; 27 differentially expressed miRNAs were identified. We were able to detect a group-specific miRNA fingerprint: miR-122-5p, miR-2110 and miR-483-5p for abdominal aortic aneurysm, miR-370-3p and miR-409-3p for coronary heart disease, miR-335-3p, miR-381-3p, miR493-5p and miR654-3p for carotid artery stenosis, miR-199a-5p, miR-215-5p, miR-3168, miR-582-3p and miR-769-5p for peripheral arterial disease. The results of the study show that some of the identified miRNAs have already been associated with atherosclerosis in previous studies. Overrepresentation analysis on this data detected biological processes that are clearly relevant for atherosclerosis, its development and progression showing the potential of these miRNAs as biomarker candidates. In a next step, the relevance of these findings on the mRNA level is to be investigated and substantiated.

Status of biomarkers for the identification of stable or vulnerable plaques in atherosclerosis

Atherosclerosis is a systemic inflammation of the arteries characterized by atherosclerotic plaque due to the accumulation of lipids, inflammatory cells, apoptotic cells, calcium and extracellular matrix (ECM) proteins. Stable plaques present a chronic inflammatory infiltration, whereas vulnerable plaques present an 'active' inflammation involved in the thinning of the fibrous cap that predisposes to plaque rupture. Several complex biological cellular processes lead plaques to evolve from stable to vulnerable predisposing them to rupture and thrombosis. In this review, we analyze some emerging circulating biomarkers related to inflammation, ECM and lipid infiltration, angiogenesis, metalloproteinases and microRNA (miRNA), as possible diagnostic and prognostic indicators of plaque vulnerability.

The expression of miR-211-5p in atherosclerosis and its influence on diagnosis and prognosis

BACKGROUND

The purpose of this study was to evaluate the diagnostic and prognostic significance of miR-211-5p in atherosclerosis (AS) by detecting the expression level in serum of patients with AS.

METHODS

A total of 85 healthy controls and 90 asymptomatic AS patients participated in this study. The expression level of miR-211-5p in all subjects were measured by qRT-PCR. Spearman correlation coefficient was used to evaluate the correlation of miR-211-5p with CRP and CIMT. The ROC curve was established to assess the diagnostic value of miR-211-5p in AS. The Kaplan-Meier survival curve and multivariate COX regression analysis were used to evaluate the prognostic significance of miR-211-5p in AS.

RESULTS

The expression levels of miR-211-5p in AS patients were significantly lower than in healthy controls (P < 0.001), and miR-211-5p showed a significant negative correlation with CRP (r =  - 0.639, P < 0.001) and CIMT (r =  - 0.730, P < 0.001). The AUC of the ROC curve was 0.900, the specificity and the sensitivity were 84.7% and 78.9%, respectively, which indicating that miR-211-5p had diagnostic value for AS. Survival analysis showed that patients with low miR-211-5p expression were more likely to have cardiovascular end-point events (Log rank P = 0.013).

CONCLUSION

Serum miR-211-5p could be used as a new biomarker for the diagnosis of AS, and the low expression of miR-211-5p is associated with the poor prognosis of AS.

Exploring the regulatory roles of circular RNAs in the pathogenesis of atherosclerosis

Circular RNAs (circRNAs) are a class of noncoding RNAs with a covalently closed loop structure. Recent evidence has shown that circRNAs can regulate gene transcription, alternative splicing, microRNA (miRNA) "molecular sponges", RNA-binding proteins and protein translation. Atherosclerosis is one of the leading causes of death worldwide, and more studies have indicated that circRNAs are related to atherosclerosis pathogenesis, including vascular endothelial cells, vascular smooth muscle cells, inflammation and lipid metabolism. In this review, we systematically summarize the biogenesis, characteristics and functions of circRNAs with a focus on their roles in the pathogenesis of atherosclerosis.

Endothelial-derived cardiovascular disease-related microRNAs elevated with prolonged sitting pattern among postmenopausal women

Time spent sitting is positively correlated with endothelial dysfunction and cardiovascular disease risk. The underlying molecular mechanisms are unknown. MicroRNAs contained in extracellular vesicles (EVs) reflect cell/tissue status and mediate intercellular communication. We explored the association between sitting patterns and microRNAs isolated from endothelial cell (EC)-derived EVs. Using extant actigraphy based sitting behavior data on a cohort of 518 postmenopausal overweight/obese women, we grouped the woman as Interrupted Sitters (IS; N = 18) or Super Sitters (SS; N = 53) if they were in the shortest or longest sitting pattern quartile, respectively. The cargo microRNA in EC-EVs from the IS and SS women were compared. MicroRNA data were weighted by age, physical functioning, MVPA, device wear days, device wear time, waist circumference, and body mass index. Screening of CVD-related microRNAs demonstrated that miR-199a-5p, let-7d-5p, miR-140-5p, miR-142-3p, miR-133b level were significantly elevated in SS compared to IS groups. Group differences in let-7d-5p, miR-133b, and miR-142-3p were validated in expanded groups. Pathway enrichment analyses show that mucin-type O-glycan biosynthesis and cardiomyocyte adrenergic signaling (P < 0.001) are downstream of the three validated microRNAs. This proof-of-concept study supports the possibility that CVD-related microRNAs in EC-EVs may be molecular transducers of sitting pattern-associated CVD risk in overweight postmenopausal women.

Exercise-induced changes in miRNA expression in coronary artery disease

OBJECTIVES

Micro ribonucleic acids (miRNAs) are small non-coding RNA molecules that control gene expression by translational inhibition. Exercise has been shown to affect several miRNAs' expression in healthy subjects, but this has not yet been studied in patients with coronary artery disease (CAD). Since exercise training confers beneficial long-term effects and may also trigger acute coronary events, it is of utmost interest to be able to identify those who are risk for untoward effects. Therefore, we set out to assess miRNA expression in response to maximal ergospirometry in patients with CAD.

METHODS

Total RNA was extracted from blood drawn immediately before and 5 min after maximal cycle-ergospirometry (10 male and 10 female CAD patients). A qRT-PCR was performed for 187 target miRNAs associated with endothelial function/dysfunction, cardiovascular disease, myocardial infarction, and sudden cardiac death.

RESULTS

In response to a maximal ergospirometry, 33 miRNAs significantly changed their expression levels. Of these miRNAs 16 were significantly differently expressed between gender. Using multi-variance analysis, nine miRNAs (let-7e-5p; miR-1; miR-19b-1-5p; miR-103a-3p; miR-148b-3p; miR-181b-5p; miR-188-5p; miR-423-5p; miR-874-3p) showed significantly different responses to maximal ergospirometry between genders.

CONCLUSIONS

We report for the first time that in patients with CAD, miRNA expression is amenable to maximal ergospirometry and that the extent of changes differs between genders. Affected by exercise and gender were miRNAs that are associated, among others, with pathways for glucose metabolism, oxidative stress, and angiogenesis. Future studies should assess whether disease-specific miRNA expression in response to maximal exercise might serve as a marker for patient outcome.

miR-141-3p Reduces Cell Migration and Proliferation in an In Vitro Modelof Atherosclerosis by Targeting Wnt5a

BACKGROUND

Atherosclerosis (AS) is a type of chronic vascular disease that is also a leading cause of numerous cardiovascular diseases in humans. The biomolecules responsible for the roles of microRNA (miR)-141-3p during AS development are less understood.

METHODS

The relation between Wnt5a and miR-141-3p was predicted using bioinformatics software TargetScan 7.1, and confirmed via dual luciferase reporter assay. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and immunoblotting were conducted for examining miR-141-3p and Wingless and Int-1 (Wnt)5a expression levels. Additionally, transwell migration and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays were conducted for analyzing cell migration and proliferation, respectively.

RESULTS

miR-141-3p was decreased in oxidized low-density lipoprotein (ox-LDL)-treated human vascular smooth muscle cells (VSMCs). Pretreatment with miR-141-3p mimic inhibited cell migration and proliferation in ox-LDL-induced VSMCs. Wnt5a was verified to act as the target of miR-141-3p in VSMCs. pcDNA3-Wnt5a partially reversed the effects of miR-141-3p mimic in ox-LDL-stimulated VSMCs.

CONCLUSION

miR-141-3p mimic decreased the damage in an AS model by targeting Wnt5a, thereby presenting a novel potential therapeutic target for treating AS.

Interfering microRNA-410 attenuates atherosclerosis via the HDAC1/KLF5/IKBα/NF-κB axis

MicroRNA (miR)-410 plays a potential role in the pathogenesis of atherosclerosis. The current study mainly focuses on the underlying mechanism of miR-410/histone deacetylase 1 (HDAC1)/KLF5/nuclear factor κB (NF-κB) inhibitor α (IKBα)/NF-κB axis in atherosclerosis. miR-410 expression was determined using quantitative real-time PCR in both mouse models of atherosclerosis and human umbilical endothelial cells (HUVECs) treated with oxidized low-density lipoprotein (ox-LDL). The study subsequently predicted regulators associated with miR-410 through bioinformatics, and their binding relation was further verified through dual luciferase reporter gene and RNA immunoprecipitation (RIP) assays, and how HDAC1 regulated KLF5 was tested through coimmunoprecipitation (coIP). In HUVECs, miR-410 and HDAC1 mRNA expression; HDAC1, KLF5, IKBα, p65, p-p65, VCAM-1, ICAM-1, and MCP-1 protein expression; and inflammatory cytokine expressions were detected using quantitative real-time PCR, western blot, and ELISA. The present study further tested cell functions by Cell Counting Kit-8 (CCK-8), flow cytometry, and the colony-formation assay. It was revealed that miR-410 could target HDAC1, whereas HDAC1 could target transcription factor KLF5, increasing IKBα expression, thus suppressing NF-κB in atherosclerosis. Furthermore, silencing miR-410 or overexpressing HDAC1 increased cell viability and suppressed apoptosis and an inflammatory reaction in HUVECs in atherosclerosis. Blocking miR-410 promotes HDAC1 expression and increases IKBα levels through KLF5 to suppress NF-κB, thus preventing development of atherosclerosis.

Circulating miRNAs Are Associated with the Systemic Extent of Atherosclerosis: Novel Observations for miR-27b and miR-146

The mechanisms that regulate the systemic extent of atherosclerosis are not fully understood. We investigated whether the expression of circulating miRNAs is associated with the extent of stable atherosclerosis to a single territory or multiple territories (polyvascular) and with the severity of atherosclerosis in each territory. Ninety-four participants were prospectively recruited and divided into five age- and sex-matched groups: presenting no atherosclerosis, isolated coronary atherosclerosis, coronary and lower extremity atherosclerosis, coronary and carotid atherosclerosis, and atherosclerosis of the coronary, lower extremity, and carotid territories. The expression of six circulating miRNAs with distinct biological roles was assessed. The expression of miR-27b and miR-146 differed across groups (p < 0.05), showing a decrease in the presence of atherosclerosis, particularly in the three territories. miR-27b and miR-146 expression decreased in association with a higher severity of coronary, lower extremity, and carotid atherosclerosis. Polyvascular atherosclerosis involving the three territories was independently associated with a decreased miR-27b and miR-146 expression. Both miRNAs presented an area under the curve of ≥0.75 for predicting polyvascular atherosclerosis involving the three territories. To conclude, miR-27b and miR-146 were associated with the presence of severe polyvascular atherosclerosis and with the atherosclerosis severity in each territory. Both are potential biomarkers of severe systemic atherosclerosis.

miR-454-3p prevents ox-LDL-induced apoptosis in HAECs by targeting TRPC3

Endothelial-cell (EC) apoptosis serves a vital role in the pathogenesis of atherosclerosis. Accumulating evidence has implicated microRNA (miRNA/miR) dysregulation in EC apoptosis. Although the role of miR-454-3p in carcinogenesis has been well documented, its role and underlying mechanism in EC apoptosis remain unclear. In the present study, the results revealed that miR-454-3p expression was substantially downregulated in human aortic endothelial cells (HAECs) following oxidized low-density lipoprotein (ox-LDL) treatment. miR-454-3p suppression significantly attenuated the viability of HAECs, while miR-454-3p overexpression repressed ox-LDL-induced HAEC apoptosis. Bioinformatics analysis and luciferase reporter assays revealed that transient receptor potential canonical 3 (TRPC3), a key regulator of atherosclerosis development, was the direct target of miR-454-3p. Furthermore, TRPC3 overexpression abolished the anti-apoptotic effect of miR-454-3p on HAECs. These results revealed a novel role of miR-454-3p in ox-LDL-induced apoptosis in HAECs.

MiR-223-3p in Cardiovascular Diseases: A Biomarker and Potential Therapeutic Target

Cardiovascular diseases, involving vasculopathy, cardiac dysfunction, or circulatory disturbance, have become the major cause of death globally and brought heavy social burdens. The complexity and diversity of the pathogenic factors add difficulties to diagnosis and treatment, as well as lead to poor prognosis of these diseases. MicroRNAs are short non-coding RNAs to modulate gene expression through directly binding to the 3′-untranslated regions of mRNAs of target genes and thereby to downregulate the protein levels post-transcriptionally. The multiple regulatory effects of microRNAs have been investigated extensively in cardiovascular diseases. MiR-223-3p, expressed in multiple cells such as macrophages, platelets, hepatocytes, and cardiomyocytes to modulate their cellular activities through targeting a variety of genes, is involved in the pathological progression of many cardiovascular diseases. It participates in regulation of several crucial signaling pathways such as phosphatidylinositol 3-kinase/protein kinase B, insulin-like growth factor 1, nuclear factor kappa B, mitogen-activated protein kinase, NOD-like receptor family pyrin domain containing 3 inflammasome, and ribosomal protein S6 kinase B1/hypoxia inducible factor 1 α pathways to affect cell proliferation, migration, apoptosis, hypertrophy, and polarization, as well as electrophysiology, resulting in dysfunction of cardiovascular system. Here, in this review, we will discuss the role of miR-223-3p in cardiovascular diseases, involving its verified targets, influenced signaling pathways, and regulation of cell function. In addition, the potential of miR-223-3p as therapeutic target and biomarker for diagnosis and prediction of cardiovascular diseases will be further discussed, providing clues for clinicians.

Methotrexate attenuates vascular inflammation through an adenosine-microRNA-dependent pathway

Endothelial cell (EC) activation is an early hallmark in the pathogenesis of chronic vascular diseases. MicroRNA-181b (Mir181b) is an important anti-inflammatory mediator in the vascular endothelium affecting endotoxemia, atherosclerosis, and insulin resistance. Herein, we identify that the drug methotrexate (MTX) and its downstream metabolite adenosine exert anti-inflammatory effects in the vascular endothelium by targeting and activating Mir181b expression. Both systemic and endothelial-specific Mir181a2b2-deficient mice develop vascular inflammation, white adipose tissue (WAT) inflammation, and insulin resistance in a diet-induced obesity model. Moreover, MTX attenuated diet-induced WAT inflammation, insulin resistance, and EC activation in a Mir181a2b2-dependent manner. Mechanistically, MTX attenuated cytokine-induced EC activation through a unique adenosine-adenosine receptor A3-SMAD3/4-Mir181b signaling cascade. These findings establish an essential role of endothelial Mir181b in controlling vascular inflammation and that restoring Mir181b in ECs by high-dose MTX or adenosine signaling may provide a potential therapeutic opportunity for anti-inflammatory therapy.

Endothelial dysfunction in neuroprogressive disorders-causes and suggested treatments

BACKGROUND

Potential routes whereby systemic inflammation, oxidative stress and mitochondrial dysfunction may drive the development of endothelial dysfunction and atherosclerosis, even in an environment of low cholesterol, are examined.

MAIN TEXT

Key molecular players involved in the regulation of endothelial cell function are described, including PECAM-1, VE-cadherin, VEGFRs, SFK, Rho GEF TRIO, RAC-1, ITAM, SHP-2, MAPK/ERK, STAT-3, NF-κB, PI3K/AKT, eNOS, nitric oxide, miRNAs, KLF-4 and KLF-2. The key roles of platelet activation, xanthene oxidase and myeloperoxidase in the genesis of endothelial cell dysfunction and activation are detailed. The following roles of circulating reactive oxygen species (ROS), reactive nitrogen species and pro-inflammatory cytokines in the development of endothelial cell dysfunction are then described: paracrine signalling by circulating hydrogen peroxide, inhibition of eNOS and increased levels of mitochondrial ROS, including compromised mitochondrial dynamics, loss of calcium ion homeostasis and inactivation of SIRT-1-mediated signalling pathways. Next, loss of cellular redox homeostasis is considered, including further aspects of the roles of hydrogen peroxide signalling, the pathological consequences of elevated NF-κB, compromised S-nitrosylation and the development of hypernitrosylation and increased transcription of atherogenic miRNAs. These molecular aspects are then applied to neuroprogressive disorders by considering the following potential generators of endothelial dysfunction and activation in major depressive disorder, bipolar disorder and schizophrenia: NF-κB; platelet activation; atherogenic miRs; myeloperoxidase; xanthene oxidase and uric acid; and inflammation, oxidative stress, nitrosative stress and mitochondrial dysfunction.

CONCLUSIONS

Finally, on the basis of the above molecular mechanisms, details are given of potential treatment options for mitigating endothelial cell dysfunction and activation in neuroprogressive disorders.

Endothelial progenitor cell-derived exosomes ameliorate endothelial dysfunction in a mouse model of diabetes

Atherosclerosis is a serious cardiovascular complication of diabetes characterized by inflammation and endothelial damage. Indeed, dysfunction of the endothelium is considered an early marker of atherosclerosis. Endothelial progenitor cells (EPCs) are prerequisites for blood vessels lined with endothelial cells (ECs), which produce many factors to regulate blood vessel function. Importantly, EPCs also repair some dysfunctions in ECs. Exosomes have been associated with the occurrence and development of disease. Here, we analyzed the microRNAs (miRNAs) contained in exosomes derived from EPCs by using next-generation sequencing. We found that most of the top 10 highest expressed miRNAs in these exosomes were related to atherosclerosis. In a mouse model of atherosclerotic diabetes, treatment with EPC-derived exosomes significantly reduced the production of diabetic atherosclerotic plaques and inflammatory factors. In an in vitro assay examining the contractility of the thoracic aorta from these mice, the addition of EPC-derived exosomes significantly ameliorated the observed endothelium-dependent contractile dysfunction. Taken together, these results indicated that EPC-derived exosomes ameliorated atherosclerotic endothelial dysfunction in a mouse model of atherosclerotic diabetes. Thus, the present study provides a potential therapeutic application of EPC-derived exosomes in cardiovascular disease.

Interactome of miRNAs and transcriptome of human umbilical cord endothelial cells exposed to short-term simulated microgravity

Adaptation of humans in low gravity conditions is a matter of utmost importance when efforts are on to a gigantic leap in human space expeditions for tourism and formation of space colonies. In this connection, cardiovascular adaptation in low gravity is a critical component of human space exploration. Deep high-throughput sequencing approach allowed us to analyze the miRNA and mRNA expression profiles in human umbilical cord vein endothelial cells (HUVEC), cultured under gravity (G), and stimulated microgravity (MG) achieved with a clinostat. The present study identified totally 1870 miRNAs differentially expressed in HUVEC under MG condition when compared to the cells subjected to unitary G conditions. The functional association of identified miRNAs targeting specific mRNAs revealed that miRNAs, hsa-mir-496, hsa-mir-151a, hsa-miR-296-3p, hsa-mir-148a, hsa-miR-365b-5p, hsa-miR-3687, hsa-mir-454, hsa-miR-155-5p, and hsa-miR-145-5p differentially regulated the genes involved in cell adhesion, angiogenesis, cell cycle, JAK-STAT signaling, MAPK signaling, nitric oxide signaling, VEGF signaling, and wound healing pathways. Further, the q-PCR based experimental studies of upregulated and downregulated miRNA and mRNAs demonstrate that the above reported miRNAs influence the cell proliferation and vascular functions of the HUVEC in MG conditions effectively. Consensus on the interactome results indicates restricted fluctuations in the transcriptome of the HUVEC exposed to short-term MG that could lead to higher levels of endothelial functions like angiogenesis and vascular patterning.

Abnormal Endothelial Gene Expression Associated With Early Coronary Atherosclerosis

Background We examined feasibility of a unique approach towards gaining insight into heritable risk for early atherosclerosis: surveying gene expression by endothelial cells from living subjects. Methods and Results Subjects aged <50 years (mean age, 37; range, 22-49) without obstructive coronary artery disease underwent coronary reactivity testing that identified them as having normal or abnormal coronary endothelial function. Cultures of Blood Outgrowth Endothelial Cells (BOEC) from 6 normal and 13 abnormal subjects passed rigorous quality control and were used for microarray assessment of gene expression. Of 9 genes differentially expressed at false discovery rate <0.1%, we here focus upon abnormal subjects having elevated expression of HMGB1 (high mobility group box 1) which we unexpectedly found to be linked to low LAMC1 (laminin gamma 1) expression. This linkage was corroborated by 3 of our past studies and confirmed bio-functionally. Compared with normal BOEC, abnormal BOEC released 13±3-fold more HMGB1 in response to lipopolysaccharide; and they deposited one tenth as much LAMC1 into collagen subendothelial matrix during culture. Clinical follow-up data are provided for 4 normal subjects (followed 13.4±0.1 year) and for 12 abnormal subjects (followed 9.1±4.5 years). Conclusions The known pathogenic effects of high-HMGB1 and low-LAMC1 predict that the combination would biologically converge upon the focal adhesion complex, to the detriment of endothelial shear responsiveness. This gene expression pattern may comprise a heritable risk state that promotes early coronary atherosclerosis. If so, the testing could be applied even in childhood, enabling early intervention. This approach offers a way to bridge the information gap between genetics and clinical phenotype.

Endothelial Cell Morphology Regulates Inflammatory Cells Through MicroRNA Transferred by Extracellular Vesicles

Vascular inflammation plays an important role in the pathogenesis and the development of cardiovascular diseases such as arteriosclerosis and restenosis, and the dysfunction of endothelial cells (ECs) may result in the activation of monocytes and other inflammatory cells. ECs exhibit an elongated morphology in the straight part of arteries but a cobblestone shape near the pro-atherogenic region such as branch bifurcation. Although the effects of hemodynamic forces on ECs have been widely studied, it is not clear whether the EC morphology affects its own function and thus the inflammatory response of monocytes. Here we showed that elongated ECs cultured on poly-(dimethyl siloxane) membrane surface with microgrooves significantly suppressed the activation of the monocytes in co-culture, in comparison to ECs with a cobblestone shape. The transfer of EC-conditioned medium to monocytes had the same effect, suggesting that soluble factors were involved in EC-monocyte communication. Further investigation demonstrated that elongated ECs upregulated the expression of anti-inflammatory microRNAs, especially miR-10a. Moreover, miR-10a was found in the extracellular vesicles (EVs) released by ECs and transferred to monocytes, and the inhibition of EV secretion from ECs repressed the upregulation of miR-10a. Consistently, the inhibition of miR-10a expression in ECs reduced their anti-inflammatory effect on monocytes. These results reveal that the EC morphology can regulate inflammatory response through EVs, which provides a basis for the design and the optimization of biomaterials for vascular tissue engineering.

Elevated Plasma Levels of Circulating Extracellular miR-320a-3p in Patients with Paroxysmal Atrial Fibrillation

The potential of extracellular circulating microRNAs (miRNAs) as non-invasive biomarkers of atrial fibrillation (AF) has been confirmed by a number of recent studies. However, the current data for some miRNAs are controversial and inconsistent, probably due to pre-analytical and methodological differences. In this work, we attempted to fulfill the basic pre-analytical requirements provided for circulating miRNA studies for application to paroxysmal atrial fibrillation (PAF) research. We used quantitative PCR (qPCR) to determine the relative plasma levels of circulating miRNAs expressed in the heart or associated with atrial remodeling or fibrillation with reported altered plasma/serum levels in AF: miR-146a-5p, miR-150-5p, miR-19a-3p, miR-21-5p, miR-29b-3p, miR-320a-3p, miR-328-3p, miR-375-3p, and miR-409-3p. First, in a cohort of 90 adult outpatient clinic patients, we found that the plasma level of miR-320a-3p was elevated in PAF patients compared to healthy controls and hypertensive patients without AF. We further analyzed the impact of medication therapies on miRNA relative levels and found elevated miR-320a-3p levels in patients receiving angiotensin-converting-enzyme inhibitors (ACEI) therapy. Additionally, we found that miR-320a-3p, miR-21-5p, and miR-146a-5p plasma levels positively correlated with the CHA₂DS₂-Vasc score and were elevated in subjects with CHA₂DS₂-Vasc ≥ 2. Our results indicate that, amongst the analyzed miRNAs, miR-320a-3p may be considered as a potential PAF circulating plasma biomarker, leading to speculation as to whether this miRNA is a marker of platelet state change due to ACEI therapy.

Association of Circulating microRNAs with Coronary Artery Disease and Usefulness for Reclassification of Healthy Individuals: The REGICOR Study

Risk prediction tools cannot identify most individuals at high coronary artery disease (CAD) risk. Oxidized low-density lipoproteins (oxLDLs) and microRNAs are actively involved in atherosclerosis. Our aim was to examine the association of CAD and oxLDLs-induced microRNAs, and to assess the microRNAs predictive capacity of future CAD events. Human endothelial and vascular smooth muscle cells were treated with oxidized/native low-density lipoproteins, and microRNA expression was analyzed. Differentially expressed and CAD-related miRNAs were examined in serum samples from (1) a case-control study with 476 myocardial infarction (MI) patients and 487 controls, and (2) a case-cohort study with 105 incident CAD cases and 455 randomly-selected cohort participants. MicroRNA expression was analyzed with custom OpenArray plates, log rank tests and Cox regression models. Twenty-one microRNAs, two previously undescribed (hsa-miR-193b-5p and hsa-miR-1229-5p), were up- or down-regulated upon cell treatment with oxLDLs. One of the 21, hsa-miR-122-5p, was also upregulated in MI cases (fold change = 4.85). Of the 28 CAD-related microRNAs tested, 11 were upregulated in MI cases-1 previously undescribed (hsa-miR-16-5p)-, and 1/11 was also associated with CAD incidence (adjusted hazard ratio = 0.55 (0.35–0.88)) and improved CAD risk reclassification, hsa-miR-143-3p. We identified 2 novel microRNAs modulated by oxLDLs in endothelial cells, 1 novel microRNA upregulated in AMI cases compared to controls, and one circulating microRNA that improved CAD risk classification.

Effect of miR-144-5p on the proliferation, migration, invasion and apoptosis of human umbilical vein endothelial cells by targeting RICTOR and its related mechanisms

The purpose of the present study was to investigate the effect of microRNA (miR)-144-5p on human umbilical vein endothelial cells (HUVECs) to explore the role of miR-144-5p in atherosclerosis. miR-144-5p expression was upregulated in HUVECs using miR-144-5p mimics. The relative expression level of miR-144-5p in HUVECs was detected using reverse transcription-quantitative PCR (RT-qPCR). Cell proliferation was detected by performing an MTT assay. Apoptosis was determined via flow cytometry. Cell migration ability was detected by a wound-healing assay. Cell invasion was determined by a transwell assay. The protein levels of phosphorylated (p)-PI3K, p-Akt and endothelial nitric oxide synthase (eNOS) were detected using western blot analysis. The binding sites between miR-144-5p and 3'-untranslated region of rapamycin-insensitive companion of mTOR (RICTOR) mRNA were predicted by TargetScan and confirmed by a dual luciferase reporter assay. The present study showed that miR-144-5p mimics significantly inhibited cell proliferation and induced apoptosis in HUVECs. In addition, miR-144-5p mimics could suppress migration and invasion of HUVECs. Further analysis identified that RICTOR was a direct target gene of miR-144-5p. Moreover, miR-144-5p upregulation decreased the protein level of p-PI3K, p-Akt and eNOS. In conclusion, miR-144-5p regulated HUVEC proliferation, migration, invasion, and apoptosis through affecting the PI3K-Akt-eNOS signaling pathway by altering the expression of RICTOR. These results indicated that miR-144-5p may be a potential target for the prevention and treatment of atherosclerosis.

Adipose-derived mesenchymal stem cells-derived exosome-mediated microRNA-342-5p protects endothelial cells against atherosclerosis

Exosomes are reported to mediate several disease-related microRNAs (miRNAs) to affect the progression of diseases, including atherosclerosis. Here, we aimed to screen the atherosclerosis-associated miRNAs and preliminarily investigate the potential regulatory mechanism of atherosclerosis. First, the lesion model for human umbilical vein endothelial cells (HUVECs) was favorably constructed. Later, through RNA-sequencing and bioinformatics analyses, miR-342-5p was identified in lesion model for HUVECs. MiR-342-5p overexpression or knockdown evidently promoted or inhibited the apoptosis of HUVECs impaired by H₂O₂. Mechanistically, PPP1R12B was found to have great potential as a target of miR-342-5p in HUVECs impaired by H₂O₂, supported by RNA-sequencing and a series of bioinformatics analyses. Meanwhile, the effect of miR-342-5p on PPP1R12B expression in HUVECs’ lesion model was explored, revealing that miR-342-5p had an inhibitory role in PPP1R12B expression. Additionally, adipose-derived mesenchymal stem cells (ADSCs) in spindle-like shape and their derived exosomes with 30 to 150 nm diameter were characterized. Furthermore, results showed miR-342-5p was evidently decreased in the presence of ADSCs-derived exosomes. These findings indicated ADSCs-derived exosomes restrained the expression of miR-324-5p in lesion model. Collectively, this work demonstrates an atherosclerosis-associated miR-342-5p and reveals a preliminary possible mechanism in which miR-342-5p mediated by ADSCs-derived exosomes protects endothelial cells against atherosclerosis.

MiRNA Expression is Associated with Clinical Variables Related to Vascular Remodeling in the Kidney and the Brain in Type 2 Diabetes Mellitus Patients

Background: The association of vascular remodeling in the kidney and the brain with a particular microRNAs (miRNA) profile is not well studied.Methods: Seventy-six patients with Type 2 diabetes and 11 healthy subjects were assessed concerning urine albumin: creatinine ratio (UACR), biomarkers of podocyte injury and of proximal tubule (PT) dysfunction. MiRNA were quantified in blood and urine by a real-time PCR System. Cerebrovascular ultrasound measurements were performed in the carotid and middle cerebral arteries.Results: MiRNA21 and miRNA124 correlated positively with nephrin, podocalyxin, synaptopodin, urinary N-acetyl-D-glucosaminidase (NAG), urinary kidney-injury molecule-1 (KIM-1), UACR, and negatively with eGFR; miRNA125a, 126, 146a, 192 correlated negatively with nephrin, podocalyxin, synaptopodin, urinary NAG, urinary KIM-1, UACR, and directly with eGFR. Plasma miRNA-21 and miRNA192 correlated directly with cerebral hemodynamics parameters of atherosclerosis and arteriosclerosis. MiRNA-124, 125a, 126, 146a showed negative correlations with the same parameters.Conclusions: In Type 2 diabetes patients there is an association of vascular remodeling in the brain and the kidney with a specific miRNAs pattern. Cerebrovascular changes occur even in normoalbuminuric patients, with 'high-to-normal' levels of podocyte injury and PT dysfunction biomarkers. These phenomena may be explained by the variability of miRNA expression within the two organs in early DKD.

MicroRNAs as Therapeutic Targets and Clinical Biomarkers in Atherosclerosis

Atherosclerotic cardiovascular disease remains the leading cause of morbidity and mortality worldwide. Atherosclerosis develops over several decades and is mediated by a complex interplay of cellular mechanisms that drive a chronic inflammatory milieu and cell-to-cell interactions between endothelial cells, smooth muscle cells and macrophages that promote plaque development and progression. While there has been significant therapeutic advancement, there remains a gap where novel therapeutic approaches can complement current therapies to provide a holistic approach for treating atherosclerosis to orchestrate the regulation of complex signalling networks across multiple cell types and different stages of disease progression. MicroRNAs (miRNAs) are emerging as important post-transcriptional regulators of a suite of molecular signalling pathways and pathophysiological cellular effects. Furthermore, circulating miRNAs have emerged as a new class of disease biomarkers to better inform clinical diagnosis and provide new avenues for personalised therapies. This review focusses on recent insights into the potential role of miRNAs both as therapeutic targets in the regulation of the most influential processes that govern atherosclerosis and as clinical biomarkers that may be reflective of disease severity, highlighting the potential theranostic (therapeutic and diagnostic) properties of miRNAs in the management of cardiovascular disease.

MicroRNAs as the actors in the atherosclerosis scenario

Atherosclerosis is considered as the most common cardiovascular disease and a leading cause of global mortality, which develops through consecutive steps. Various cellular and molecular biomarkers such as microRNAs are identified to be involved in atherosclerosis progression. MicroRNAs are a group of endogenous, short, non-coding RNAs, which are able to bind to specific sequences on target messenger RNAs and thereby modulate gene expression post-transcriptionally. MicroRNAs are key players in wide range of biological processes; thus, their expression level is regulated in pathophysiological conditions. Ample evidences including in vitro and in vivo studies approved a critical role of microRNAs in epigenetic and the sequential processes of atherosclerosis from risk factors to plaque formation, progression, and rupture. Based on these findings, miRNAs seems to be promising candidates for therapeutic approach. This review summarizes the role of miRNAs in atherosclerosis development, epigenetic, and therapy. Moreover, the application of exosomes in miRNA delivery, and/or their prognostic and diagnostic values are also discussed.

MicroRNAs as Potential Biomarkers in Atherosclerosis

Atherosclerosis is a complex multifactorial disease that, despite advances in lifestyle management and drug therapy, remains to be the major cause of high morbidity and mortality rates from cardiovascular diseases (CVDs) in industrialized countries. Therefore, there is a great need in reliable diagnostic/prognostic biomarkers and effective treatment alternatives to reduce its burden. It was established that microRNAs (miRNAs/miRs), a class of non-coding single-stranded RNA molecules, can regulate the expression of genes at the post-transcriptional level and, accordingly, coordinate the cellular protein expression. Thus, they are involved not only in cell-specific physiological functions but also in the cellular and molecular mechanisms of human pathologies, including atherosclerosis. MiRNAs may be significant in the dysregulation that affects endothelial integrity, the function of vascular smooth muscle and inflammatory cells, and cellular cholesterol homeostasis that drives the initiation and growth of an atherosclerotic plaque. Besides, distinct expression patterns of several miRNAs are attributed to atherosclerotic and cardiovascular patients. In this article, the evidence indicating the multiple critical roles of miRNAs and their relevant molecular mechanisms related to atherosclerosis development and progression was reviewed. Moreover, the effects of miRNAs on atherosclerosis enabled to exploit them as novel diagnostic biomarkers and therapeutic targets that may lead to better management of atherosclerosis and CVDs.

MiR-3691-5p is upregulated in docosahexaenoic acid-treated vascular endothelial cell and targets serpin family E member 1

Endothelium, the inner cellular lining of blood vessels, has an important role in the regulation of physiological processes and its dysfunction may initiate cardiovascular complications. Previous investigations have revealed that dietary docosahexaenoic acid (DHA) is related to a lower possibility of cardiovascular disease and mortality. Until now, the molecular mechanisms in the biological activities of DHA remain largely unknown. MicroRNAs (miRNAs) play a vital role in regulating gene expression. Thus, we aimed to investigate whether DHA improves the dysfunction via regulating miRNAs. To understand the protective effects of DHA through modulating miR-3691-5p and its target genes for palmitic acid (PAL) induced apoptosis in endothelial cells. The present study demonstrated that DHA upregulated miR-3691-5p expression, and downregulated the expression of its target gene serpin family E member 1 (SERPINE1). MiR-mimics and inhibitors modulation results indicated that miR-3691-5p regulates endothelial apoptosis through activating antiapoptotic response which controlled by the STAT3 signaling pathway. In conclusion, we have shown that PAL-induced apoptosis could be decreased by DHA treatment through miR-3691-5/SERPINE1 pathways.

Regulation of microRNAs in coronary atherosclerotic plaque

Aim: Identification of microRNAs (miRNAs) associated with atherosclerosis may unravel novel therapeutic targets and biomarkers. We studied miRNAs differentially expressed between coronary atherosclerotic plaques (CAP) and healthy arteries. Materials & methods: Paired CAP and internal mammary arteries (IMA) were collected from 14 coronary artery disease patients. The miRNA profiles between diseased (CAP) and healthy (IMA) tissues were compared using microarrays and quantitative PCR. Results: Thirty-one miRNAs were differentially expressed between CAP and IMA. Among these, miR-486-5p showed a high level of regulation (12-fold), had predicted interactions with atherosclerosis-associated genes and correlated with triglyceride levels and arterial stenosis. Regulation of miR-486-5p was validated by PCR (p = 0.004). Conclusion: The miRNAs are regulated in the atherosclerotic plaque. We highlight miR-486-5p whose role in atherosclerosis requires further investigation.

The role of microvesicles containing microRNAs in vascular endothelial dysfunction

Many studies have shown that endothelial dysfunction is associated with a variety of cardiovascular diseases. The endothelium is one of the primary targets of circulating microvesicles. Besides, microRNAs emerge as important regulators of endothelial cell function. As a delivery system of microRNAs, microvesicles play an active and important role in regulating vascular endothelial function. In recent years, some studies have shown that microvesicles containing microRNAs regulate the pathophysiological changes in vascular endothelium, such as cell apoptosis, proliferation, migration and inflammation. These studies have provided some clues for the possible roles of microvesicles and microRNAs in vascular endothelial dysfunction‐associated diseases, and opened the door towards discovering potential novel therapeutic targets. In this review, we provide an overview of the main characteristics of microvesicles and microRNAs, summarizing their potential role and mechanism in endothelial dysfunction, and discussing the clinical application and existing problems of microvesicles for better translational applications.

Long Noncoding RNA HOXA-AS3 Integrates NF-κB Signaling To Regulate Endothelium Inflammation

The long noncoding RNA HOXA-AS3 has recently been reported to act as a critical regulator in inflammation-linked lung adenocarcinoma. However, the roles of HOXA-AS3 in endothelium inflammation and related vascular disorders remain poorly defined. In the current study, we identified HOXA-AS3 to be a critical activator to promote NF-κB-mediated endothelium inflammation. HOXA-AS3, a chromatin-associated regulator which colocalizes with NF-κB at specific gene promoters, was found to interact with NF-κB and positively regulate its activity through control of the expression of the NF-κB inhibitor protein IκBα and the acetylation status at the K310 site of p65. More importantly, clinicopathological analysis showed that HOXA-AS3 expression has a significant positive correlation with atherosclerosis. Thus, we conclude that HOXA-AS3 may serve as a crucial biomarker for the clinical diagnosis of atherosclerosis, as well as a promising therapeutic target for the treatment of multiple inflammatory vascular diseases. In addition, this study suggests the functional importance of HOXA-AS3 in the regulation of inflammatory disorders.

MicroRNA-181a-5p and microRNA-181a-3p cooperatively restrict vascular inflammation and atherosclerosis

MicroRNAs have emerged as important post-transcriptional regulators of gene expression and are involved in diverse diseases and cellular process. Decreased expression of miR-181a has been observed in the patients with coronary artery disease, but its function and mechanism in atherogenesis is not clear. This study was designed to determine the roles of miR-181a-5p, as well as its passenger strand, miR-181a-3p, in vascular inflammation and atherogenesis. We found that the levels of both miR-181a-5p and miR-181a-3p are decreased in the aorta plaque and plasma of apoE^−/− mice in response to hyperlipidemia and in the plasma of patients with coronary artery disease. Rescue of miR-181a-5p and miR-181a-3p significantly retards atherosclerotic plaque formation in apoE^−/− mice. MiR-181a-5p and miR-181a-3p have no effect on lipid metabolism but decrease proinflammatory gene expression and the infiltration of macrophage, leukocyte and T cell into the lesions. In addition, gain-of-function and loss-of-function experiments show that miR-181a-5p and miR-181a-3p inhibit adhesion molecule expression in HUVECs and monocytes-endothelial cell interaction. MiR-181a-5p and miR-181a-3p cooperatively receded endothelium inflammation compared with single miRNA strand. Mechanistically, miR-181a-5p and miR-181a-3p prevent endothelial cell activation through blockade of NF-κB signaling pathway by targeting TAB2 and NEMO, respectively. In conclusion, these findings suggest that miR-181a-5p and miR-181a-3p are both antiatherogenic miRNAs. MiR-181a-5p and miR-181a-3p mimetics retard atherosclerosis progression through blocking NF-κB activation and vascular inflammation by targeting TAB2 and NEMO, respectively. Therefore, restoration of miR-181a-5p and miR-181a-3p may represent a novel therapeutic approach to manage atherosclerosis.

Biomarkers of radiation-induced vascular injury

OBJECTIVE

Cancer survivorship has thrown the spotlight on the incidence of nonmalignant chronic diseases in cancer patients. Endothelial injury is increasingly recognized as a consequence of cancer treatment, particularly after radiation therapy (RT). This review is to provide a current understanding on the pathophysiological mechanisms and predictive biomarkers of radiation-induced vascular injury.

RECENT FINDINGS

Radiation directly impacts vasculature by causing endothelial apoptosis and senescence, and alterations in normal homeostasis. This altered milieu at the endothelial surface may contribute to a systemic chronic inflammatory state that is superimposed upon the cascade of normal senescence processes leading to acceleration of age-related disorders, atherosclerosis, and chronic fibrosis. Vasculature imaging, blood-based or cell-component biomarkers, and signatures of genomics, proteomics, metabolomics, and radiomics are potential tools for detection of vascular damage after irradiation.

CONCLUSIONS

Development of a valid prediction model by combining an array of imaging tools, blood-based biomarkers, coupled with novel predictors like exosomes and metabolic degradation products can serve to identify RT-induced vascular injury early for subsequent introduction of newer therapeutic approaches to counter radiation morbidity.

MiR-590 Inhibits Endothelial Cell Apoptosis by Inactivating the TLR4/NF-κB Pathway in Atherosclerosis

PURPOSE

Previous study has well documented the anti-apoptotic effects of miR-590 on oxidized low-density lipoprotein (ox-LDL)-treated endothelial cells (ECs). However, the mechanism underlying the anti-apoptotic effects of miR-590 in ox-LDL-treated ECs remains to be further addressed.

MATERIALS AND METHODS

ApoE^-/- mice fed with a high-fat diet (HFD) and human aortic endothelial cells (HAECs) treated with ox-LDL were used as in vivo and in vitro models of atherosclerosis. The expressions of miR-590 and toll-like receptor 4 (TLR4) were detected by quantitative real-time PCR and Western blot, respectively. Atherosclerotic lesion analysis was performed using Evans blue and hematoxylin-eosin staining. Cell proliferation was assessed by MTT assay. Apoptosis was examined using flow cytometry analysis and Western blot analysis of Cleaved poly (ADP-ribose) polymerase (PARP) and Cleaved Caspase-3 levels. The effect of miR-590 on TLR4/nuclear factor kappa B (NF-κB) pathway was evaluated by Western blot. Binding between miR-590 and TLR4 was confirmed by luciferase reporter assay and Western blot.

RESULTS

miR-590 was downregulated in the aorta tissues from HFD-fed apoE^-/- mice and ox-LDL-treated HAECs. miR-590 overexpression inhibited atherosclerotic lesion in HFD-induced apoE^-/- mice and promoted proliferation and inhibited apoptosis of ox-LDL-treated HAECs. Additionally, TLR4 was identified as a direct target of miR-590 in ox-LDL-treated HAECs. Moreover, anti-miR-590 reversed TLR4 knockdown-mediated promotion of cell proliferation and suppression of apoptosis in ox-LDL-treated HAECs. miR-590 overexpression suppressed the TLR4/NF-κB pathway, and inhibition of the TLR4/NF-κB pathway promoted cell proliferation and impeded apoptosis in ox-LDL-treated HAECs.

CONCLUSION

miR-590 promoted proliferation and blocked ox-LDL-induced apoptosis in HAECs through inhibition of the TLR4/NF-κB pathway.