Plasma microRNA-100 is associated with coronary plaque vulnerability

An Increase in Plasma MicroRNA-143 Levels in the Acute Phase Is Positively Correlated With Recovery of Cardiac Function in the Chronic Phase in Patients With Acute Myocardial Infarction

BACKGROUND

MicroRNA (miR)-143 and miR-145 are non-coding RNAs present in smooth muscle cells and the heart. However, their behavior and physiological role in patients with acute myocardial infarction (AMI) have not been clarified.

METHODS AND RESULTS

Plasma miR-143 and miR-145 concentrations were measured on Day 0 (on admission) and on Day 7 in AMI patients who could be followed up for 6 months (n=25). The control group consisted of subjects without significant coronary stenosis (n=20). Blood samples were collected from the antecubital vein, and plasma miR-143 and miR-145 concentrations were measured by quantitative reverse transcription-polymerase chain reaction. In AMI patients (n=25), left ventricular ejection fraction (LVEF) was measured by echocardiography in the acute and chronic (6 months) phases. On Day 7, plasma miR-143 and miR-145 concentrations were significantly higher in AMI patients than in the control group and on Day 0 in AMI patients. Plasma miR-143 and miR-145 concentrations increased significantly from Day 0 to Day 7. The increase in plasma miR-143 concentrations (∆miR-143) in the acute phase was positively correlated with the increase in LVEF in the chronic phase. Among many factors, only ∆miR-143 was favorably correlated with left ventricle (LV) functional recovery in the chronic phase.

CONCLUSIONS

An increase in plasma miR-143 concentrations in the acute phase may be a biomarker predicting recovery of LV function in the chronic phase in AMI patients.

Associations between circulating microRNAs and lipid-rich coronary plaques measured with near-infrared spectroscopy

Lipid-rich coronary atherosclerotic plaques often cause myocardial infarction (MI), and circulating biomarkers that reflect lipid content may predict risk of MI. We investigated the association between circulating microRNAs (miRs) are lipid-rich coronary plaques in 47 statin-treated patients (44 males) with stable coronary artery disease undergoing percutaneous coronary intervention. We assessed lipid content in non-culprit coronary artery lesions with near-infrared spectroscopy and selected the 4 mm segment with the highest measured lipid core burden index (maxLCBI_4mm). Lipid-rich plaques were predefined as a lesion with maxLCBI_4mm ≥ 324.7. We analyzed 177 circulating miRs with quantitative polymerase chain reaction in plasma samples. The associations between miRs and lipid-rich plaques were analyzed with elastic net. miR-133b was the miR most strongly associated with lipid-rich coronary plaques, with an estimated 18% increase in odds of lipid-rich plaques per unit increase in miR-133b. Assessing the uncertainty by bootstrapping, miR-133b was present in 82.6% of the resampled dataset. Inclusion of established cardiovascular risk factors did not attenuate the association. No evidence was found for an association between the other analyzed miRs and lipid-rich coronary plaques. Even though the evidence for an association was modest, miR-133b could be a potential biomarker of vulnerable coronary plaques and risk of future MI. However, the prognostic value and clinical relevance of miR-133b needs to be assessed in larger cohorts.

Role of the renin-angiotensin system in the pathophysiology of coronary heart disease and heart failure: Diagnostic biomarkers and therapy with drugs and natural products

The renin-angiotensin system (RAS) plays a pivotal role in blood pressure regulation. In some cases, this steering mechanism is affected by various deleterious factors (mainly via the overactivation of the RAS) causing cardiovascular damage, including coronary heart disease (CHD) that can ultimately lead to chronic heart failure (CHF). This not only causes cardiovascular disability and absenteeism from work but also imposes significant healthcare costs globally. The incidence of cardiovascular diseases has escalated exponentially over the years with the major outcome in the form of CHD, stroke, and CHF. The involvement of the RAS in various diseases has been extensively researched with significant limelight on CHD. The RAS may trigger a cascade of events that lead to atherosclerotic mayhem, which causes CHD and related aggravation by damaging the endothelial lining of blood vessels via various inflammatory and oxidative stress pathways. Although there are various diagnostic tests and treatments available in the market, there is a constant need for the development of procedures and therapeutic strategies that increase patient compliance and reduce the associated side effects. This review highlights the advances in the diagnostic and treatment domains for CHD, which would help in subjugating the side effects caused by conventional therapy.

microRNAs Associated with Carotid Plaque Development and Vulnerability: The Clinician's Perspective

Ischemic stroke (IS) related to atherosclerosis of large arteries is one of the leading causes of mortality and disability in developed countries. Atherosclerotic internal carotid artery stenosis (ICAS) contributes to 20% of all cerebral ischemia cases. Nowadays, atherosclerosis prevention and treatment measures aim at controlling the atherosclerosis risk factors, or at the interventional (surgical or endovascular) management of mature occlusive lesions. There is a definite lack of the established circulating biomarkers which, once modulated, could prevent development of atherosclerosis, and consequently prevent the carotid-artery-related IS. Recent studies emphasize that microRNA (miRNA) are the emerging particles that could potentially play a pivotal role in this approach. There are some research studies on the association between the expression of small non-coding microRNAs with a carotid plaque development and vulnerability. However, the data remain inconsistent. In addition, all major studies on carotid atherosclerotic plaque were conducted on cell culture or animal models; very few were conducted on humans, whereas the accumulating evidence demonstrates that it cannot be automatically extrapolated to processes in humans. Therefore, this paper aims to review the current knowledge on how miRNA participate in the process of carotid plaque formation and rupture, as well as stroke occurrence. We discuss potential target miRNA that could be used as a prognostic or therapeutic tool.

Associations between circulating microRNAs and coronary plaque characteristics: potential impact from physical exercise

Background and aims MicroRNAs (miRs) are involved in different steps in the development of atherosclerosis and are proposed as promising biomarkers of coronary artery disease (CAD). We hypothesized that circulating levels of miRs were associated with coronary plaque components assessed by radiofrequency intravascular ultrasound (RF-IVUS) before and after aerobic exercise intervention. Methods 31 patients with CAD treated with percutaneous coronary intervention (PCI) previously included in a randomized trial with aerobic interval training (AIT) or moderate continuous training (MCT) as post-PCI intervention were included. Coronary plaque characteristics by grayscale and RF-IVUS and predefined circulating candidate miRs in plasma were analysed at baseline and follow-up. Associations between miRs and coronary plaque composition, and the potential effect from exercise, were analysed using linear regression. Results Circulating levels of miR-15a-5p, miR-30e-5p, miR-92a-3p, miR-199a-3p, miR-221-3p, and miR-222-3p were associated with baseline coronary necrotic core volume. Following exercise intervention, decreased levels of miR-15a-5p, miR-93-5p, and miR-451a, and increased levels of miR-146a-5p were associated with an observed regression of coronary plaque burden. A mirPath prediction tool identified that genes regulated by miR-15a-5p, miR-199a-3p, and miR-30e-5p were significantly overrepresented in pathways related to fatty acid biosynthesis and fatty acid metabolism. Conclusion This exploratory study demonstrated six miRs associated with coronary necrotic core, a marker of plaque vulnerability. In addition, changes in four miRs were associated with a regression of coronary plaque burden following exercise intervention. These novel findings may identify potential future biomarkers of CAD and coronary plaque composition.

Comprehensive Analysis of Potential miRNA-Target mRNA-Immunocyte Subtype Network in Cerebral Infarction

INTRODUCTION

Cerebral infarction (CI) is one of the leading causes of serious long-term disability and mortality.

OBJECTIVE

We aimed to identify potential miRNAs and target mRNAs and assess the involvement of immunocyte infiltration in the process of CI.

METHODS

First, miRNA and mRNA data were downloaded from the Gene Expression Omnibus database, followed by differential expression analysis. Second, correlation analysis between differentially expressed mRNAs and differential immunocyte subtypes was performed through the CIBERSORT algorithm. Third, the regulatory network between miRNAs and immunocyte subtype-related mRNAs was constructed followed by the functional analysis of these target mRNAs. Fourth, correlation validation between differentially expressed mRNAs and differential immunocyte subtypes was performed in the GSE37587 dataset. Finally, the diagnostic ability of immunocyte subtype-related mRNAs was tested.

RESULTS

Up to 17 differentially expressed miRNAs and 3,267 differentially expressed mRNAs were identified, among which 310 differentially expressed mRNAs were significantly associated with immunocyte subtypes. Several miRNA-target mRNA-immunocyte subtype networks including hsa-miR-671-3p-ZC3HC1-neutrophils, hsa-miR-625-CD5-monocytes, hsa-miR-122-ACOX1/DUSP1/NEDD9-neutrophils, hsa-miR-455-5p-SLC24A4-monocytes, and hsa-miR-455-5p-SORL1-neutrophils were identified. LAT, ACOX1, DUSP1, NEDD9, ZC3HC1, BIN1, AKT1, DNMT1, SLC24A4, and SORL1 had a potential diagnostic value for CI.

CONCLUSIONS

The network including miRNA, target mRNA, and immunocyte subtype may be novel regulators and diagnostic and therapeutic targets in CI.

Targeting non-coding RNAs in unstable atherosclerotic plaques: Mechanism, regulation, possibilities, and limitations

Cardiovascular diseases (CVDs) caused by arteriosclerosis are the leading cause of death and disability worldwide. In the late stages of atherosclerosis, the atherosclerotic plaque gradually expands in the blood vessels, resulting in vascular stenosis. When the unstable plaque ruptures and falls off, it blocks the vessel causing vascular thrombosis, leading to strokes, myocardial infarctions, and a series of other serious diseases that endanger people's lives. Therefore, regulating plaque stability is the main means used to address the high mortality associated with CVDs. The progression of the atherosclerotic plaque is a complex integration of vascular cell apoptosis, lipid metabolism disorders, inflammatory cell infiltration, vascular smooth muscle cell migration, and neovascular infiltration. More recently, emerging evidence has demonstrated that non-coding RNAs (ncRNAs) play a significant role in regulating the pathophysiological process of atherosclerotic plaque formation by affecting the biological functions of the vasculature and its associated cells. The purpose of this paper is to comprehensively review the regulatory mechanisms involved in the susceptibility of atherosclerotic plaque rupture, discuss the limitations of current approaches to treat plaque instability, and highlight the potential clinical value of ncRNAs as novel diagnostic biomarkers and potential therapeutic strategies to improve plaque stability and reduce the risk of major cardiovascular events.

Circulating Biomarkers Reflecting Destabilization Mechanisms of Coronary Artery Plaques: Are We Looking for the Impossible?

Despite significant strides to mitigate the complications of acute coronary syndrome (ACS), this clinical entity still represents a major global health burden. It has so far been well-established that most of the plaques leading to ACS are not a result of gradual narrowing of the vessel lumen, but rather a result of sudden disruption of vulnerable atherosclerotic plaques. As most of the developed imaging modalities for vulnerable plaque detection are invasive, multiple biomarkers were proposed to identify their presence. Owing to the pivotal role of lipids and inflammation in the pathophysiology of atherosclerosis, most of the biomarkers originated from one of those processes, whereas recent advancements in molecular sciences shed light on the use of microRNAs. Yet, at present there are no clinically implemented biomarkers or any other method for that matter that could non-invasively, yet reliably, diagnose the vulnerable plaque. Hence, in this review we summarized the available knowledge regarding the pathophysiology of plaque instability, the current evidence on potential biomarkers associated with plaque destabilization and finally, we discussed if search for biomarkers could one day bring us to non-invasive, cost-effective, yet valid way of diagnosing the vulnerable, rupture-prone coronary artery plaques.

Anesthetics may modulate cancer surgical outcome: a possible role of miRNAs regulation

Background

microRNAs (miRNAs) are single-stranded and noncoding RNA molecules that control post-transcriptional gene regulation. miRNAs can be tumor suppressors or oncogenes through various mechanism including cancer cell biology, cell-to-cell communication, and anti-cancer immunity.

Main Body

Anesthetics can affect cell biology through miRNA-mediated regulation of messenger RNA (mRNA). Indeed, sevoflurane was reported to upregulate miR-203 and suppresses breast cancer cell proliferation. Propofol reduces matrix metalloproteinase expression through its impact on miRNAs, leading to anti-cancer microenvironmental changes. Propofol also modifies miRNA expression profile in circulating extracellular vesicles with their subsequent anti-cancer effects via modulating cell-to-cell communication.

Conclusion

Inhalational and intravenous anesthetics can alter cancer cell biology through various cellular signaling pathways induced by miRNAs’ modification. However, this area of research is insufficient and further study is needed to figure out optimal anesthesia regimens for cancer patients.

Oxidative Stress in Ischemic Heart Disease

One of the novel interesting topics in the study of cardiovascular disease is the role of the oxidation system, since inflammation and oxidative stress are known to lead to cardiovascular diseases, their progression and complications. During decades of research, many complex interactions between agents of oxidative stress, oxidation, and antioxidant systems have been elucidated, and numerous important pathophysiological links to na number of disorders and diseases have been established. This review article will present the most relevant knowledge linking oxidative stress to vascular dysfunction and disease. The review will focus on the role of oxidative stress in endotheleial dysfunction, atherosclerosis, and other pathogenetic processes and mechanisms that contribute to the development of ischemic heart disease.

Circulating microRNA as a Biomarker for Coronary Artery Disease

Coronary artery disease (CAD) is the leading cause of sudden cardiac death in adults, and new methods of predicting disease and risk-stratifying patients will help guide intervention in order to reduce this burden. Current CAD detection involves multiple modalities, but the consideration of other biomarkers will help improve reliability. The aim of this narrative review is to help researchers and clinicians appreciate the growing relevance of miRNA in CAD and its potential as a biomarker, and also to suggest useful miRNA that may be targets for future study. We sourced information from several databases, namely PubMed, Scopus, and Google Scholar, when collating evidentiary information. MicroRNAs (miRNA) are short, noncoding RNAs that are relevant in cardiovascular physiology and pathophysiology, playing roles in cardiac hypertrophy, maintenance of vascular tone, and responses to vascular injury. CAD is associated with changes in miRNA expression profiles, and so are its risk factors, such as abnormal lipid metabolism and inflammation. Thus, they may potentially be biomarkers of CAD. Nevertheless, there are limitations in using miRNA. These include cost and the presence of several confounding factors that may affect miRNA profiles. Furthermore, there is difficulty in the normalisation of miRNA values between published studies, due to pre-analytical variations in samples.

The Role of MicroRNAs in Regulating Cytokines and Growth Factors in Coronary Artery Disease: The Ins and Outs

Coronary artery diseases (CAD), as a leading cause of mortality around the world, has attracted the researchers' attention for years to find out its underlying mechanisms and causes. Among the various key players in the pathogenesis of CAD cytokines, microRNAs (miRNAs) are crucial. In this study, besides providing a comprehensive overview of the involvement of cytokines, growth factors, and miRNAs in CAD, the interplay between miRNA with cytokine or growth factors during the development of CAD is discussed.

Small Things Matter: Relevance of MicroRNAs in Cardiovascular Disease

MicroRNAs (miRNAs) are short sequences of non-coding RNA that play an important role in the regulation of gene expression and thereby in many physiological and pathological processes. Furthermore, miRNAs are released in the extracellular space, for example in vesicles, and are detectable in various biological fluids, such as serum, plasma, and urine. Over the last years, it has been shown that miRNAs are crucial in the development of several cardiovascular diseases (CVDs). This review discusses the (patho)physiological implications of miRNAs in CVD, ranging from cardiovascular risk factors (i.e., hypertension, diabetes, dyslipidemia), to atherosclerosis, myocardial infarction, and cardiac remodeling. Moreover, the intriguing possibility of their use as disease-specific diagnostic and prognostic biomarkers for human CVDs will be discussed in detail. Finally, as several approaches have been developed to alter miRNA expression and function (i.e., mimics, antagomirs, and target-site blockers), we will highlight the miRNAs with the most promising therapeutic potential that may represent suitable candidates for therapeutic intervention in future translational studies and ultimately in clinical trials. All in all, this review gives a comprehensive overview of the most relevant miRNAs in CVD and discusses their potential use as biomarkers and even therapeutic targets.

MicroRNA-331 and microRNA-151-3p as biomarkers in patients with ST-segment elevation myocardial infarction

We sought to analyse plasma levels of peripheral blood microRNAs (miRs) as biomarkers of ST-segment-elevation myocardial infarction (STEMI) due to type-1 myocardial infarction as a model situation of vulnerable plaque (VP) rupture. Samples of 20 patients with STEMI were compared both with a group of patients without angina pectoris in whom coronary angiogram did not reveal coronary atherosclerotic disease (no coronary atherosclerosis-NCA) and a group of patients with stable angina pectoris and at least one significant coronary artery stenosis (stable coronary artery disease-SCAD). This study design allowed us to identify miRs deregulated in the setting of acute coronary artery occlusion due to VP rupture. Based on an initial large scale miR assay screening, we selected a total of 12 miRs (three study miRs and nine controls) that were tested in the study. Two of the study miRs (miR-331 and miR-151-3p) significantly distinguished STEMI patients from the control groups, while ROC analysis confirmed their suitability as biomarkers. Importantly, this was observed in patients presenting early with STEMI, even before the markers of myocardial necrosis (cardiac troponin I, miR-208 and miR-499) were elevated, which suggests that the origin of miR-331 and miR-151-3p might be in the VP. In conclusion, the study provides two novel biomarkers observed in STEMI, which may be associated with plaque rupture.

Biomarkers of vascular disease in diabetes: the adipose-immune system cross talk

Experimental and clinical studies aimed at investigating the mechanism(s) underlying vascular complications of diabetes indicate that a great number of molecules are involved in the pathogenesis of these complications. Most of these molecules are inflammatory mediators or markers generated by immune or adipose tissue. Some of them, i.e. resistin and sortilin, have been shown to be involved in the cross talk between adipocytes and inflammatory cells. This interaction is an attractive area of research, particularly in type 2 diabetes and obesity. Other proteins, such as adiponectin and visfatin, appear to be more promising as possible vascular markers. In addition, some molecules involved in calcium/phosphorus metabolism, such as klotho and FGF23, have an involvement in the pathogenesis of diabetic vasculopathy, which appears to be dependent on the degree of vascular impairment. Inflammatory markers are a promising tool for treatment decisions while measuring plasma levels of adipokines, sortilin, Klotho and FGF23 in adequately sized longitudinal studies is expected to allow a more precise characterization of diabetic vascular disease and the optimal use of personalized treatment strategies.

Diagnostic and theranostic microRNAs in the pathogenesis of atherosclerosis

MicroRNAs (miRNAs) are a group of small single strand and noncoding RNAs that regulate several physiological and molecular signalling pathways. Alterations of miRNA expression profiles may be involved with pathophysiological processes underlying the development of atherosclerosis and cardiovascular diseases, including changes in the functions of the endothelial cells and vascular smooth muscle cells, such as cell proliferation, migration and inflammation, which are involved in angiogenesis, macrophage function and foam cell formation. Thus, miRNAs can be considered to have a crucial role in the progression, modulation and regulation of every stage of atherosclerosis. Such potential biomarkers will enable us to predict therapeutic response and prognosis of cardiovascular diseases and adopt effective preclinical and clinical treatment strategies. In the present review article, the current data regarding the role of miRNAs in atherosclerosis were summarized and the potential miRNAs as prognostic, diagnostic and theranostic biomarkers in preclinical and clinical studies were further discussed. The highlights of this review are expected to present opportunities for future research of clinical therapeutic approaches in vascular diseases resulting from atherosclerosis with an emphasis on miRNAs.

Alteration in the expression of the renin-angiotensin system in the myocardium of mice conceived by in vitro fertilization

Epidemiological studies have revealed that offspring conceived by in vitro fertilization (IVF) have an elevated risk of cardiovascular malformations at birth, and are more predisposed to cardiovascular diseases. The renin-angiotensin system (RAS) plays an essential role in both the pathogenesis of congenital heart disease in fetuses and cardiovascular dysfunction in adults. This study aimed to assess the relative expression levels of genes in the RAS pathway in mice conceived using IVF, compared to natural mating with superovulation. Results demonstrated that expression of the angiotensin II receptor type 1 (AGTR1), connective tissue growth factor (CTGF), and collagen 3 (COL3), in the myocardial tissue of IVF-conceived mice, was elevated at 3 weeks, 10 weeks, and 1.5 years of age, when compared to their non-IVF counterparts. These data were supported by microRNA microarray analysis of the myocardial tissue of aged IVF-conceived mice, where miR-100, miR-297, and miR-758, which interact with COL3, AGTR1, and COL1 respectively, were upregulated when compared to naturally mated mice of the same age. Interestingly, bisulfite sequencing data indicated that IVF-conceived mice exhibited decreased methylation of CpG sites in Col1. In support of our in vivo investigations, miR-297 overexpression was shown to upregulate AGTR1 and CTGF, and increased cell proliferation in cultured H9c2 cardiomyocytes. These findings indicate that the altered expression of RAS in myocardial tissue might contribute to cardiovascular malformation and/or dysfunction in IVF-conceived offspring. Furthermore, these cardiovascular abnormalities might be the result of altered DNA methylation and abnormal regulation of microRNAs.

Impact of the triglyceride level on coronary plaque components in female patients with coronary artery disease treated with statins

Several studies have reported that elevated triglyceride (TG) levels may be more strongly associated with an increased risk of coronary artery disease (CAD) in females than in males. We examined gender differences in the relationship between TG levels and coronary atherosclerosis using integrated backscatter intravascular ultrasound (IB IVUS) in CAD patients treated with statins. Three hundred seventy-eight CAD patients (105 females and 273 males) who underwent percutaneous coronary intervention using IB IVUS, and who were already receiving statin treatment, were included. Gray-scale and IB IVUS examinations were performed for the non-culprit segment of a coronary artery and fasting serum TG concentrations were measured. We found that TG levels were significantly correlated with increased lipid (r = 0.40, p < 0.001) and decreased fibrous (r = - 0.37, p < 0.001) plaque components in females, but not in males. Low-density lipoprotein cholesterol and high-density lipoprotein cholesterol levels were not related to either the gray-scale or IB IVUS parameters in both genders. After adjustment for conventional coronary risk factors by a multivariate stepwise regression analysis, higher TG levels in females were independently associated with increased lipid (β = 0.31, p< 0.001) contents in coronary plaques. In conclusion, among CAD patients treated with statins, TG levels were associated with lipid-rich coronary plaques in females, but not in males. TG levels may be more important indicators of residual risk after statin treatment in females than in males.

Circulating miRNA levels differ with respect to carotid plaque characteristics and symptom occurrence in patients with carotid artery stenosis and provide information on future cardiovascular events

Introduction

Circulating microRNAs (miRNAs) levels are potentially important biomarkers and therapeutic targets of cerebral ischemic event (CIE) in patients with internal carotid artery stenosis (ICAS).

Aim

This prospective study investigated associations between circulating miRNAs and symptomatic and asymptomatic ICAS, carotid plaque morphology and future cardiovascular events.

Material and methods

Circulating miRNAs (miR-1-3p, miR-16-5p, miR-34a-5p, miR-124-3p, miR-133a-3p, miR-133b, miR-134-5p, miR-208b-3p, miR-375 and miR-499-5p) were analyzed in 92 consecutive patients with significant ICAS referred for revascularization. Group I comprised 65 subjects (41 males, age 69.3 ±9.7 years) with a recent CIE. Group II comprised 27 patients (15 males, age 68.2 ±8.4 years) with asymptomatic ICAS. The ICAS degree and plaque morphology was assessed by ultrasonography. The incidences of cardiovascular death (CVD), myocardial infarction (MI) and recurrent CIE (CVD/MI/CIE) were recorded prospectively (mean: 38.7 ±3.8 months).

Results

Groups II and I differed significantly in levels of miR-124-3p (p = 0.036), miR-133a-3p (p = 0.043) and miR-134-5p (p = 0.02). Hypoechogenic, as compared to echogenic, plaques differed in levels of miR-124-3p (p = 0.038), miR-34a-5p (p = 0.006), miR-133b (p = 0.048), miR-134-5p (p = 0.045), and miR-375 (p = 0.016), while calcified plaques differed in miR-16-5p (p = 0.023). Ulcerated plaques showed higher levels of miR-1-3p (p = 0.04) and miR-16-5p (p = 0.003), while thrombotic plaques showed lower levels of miR-1-3p (p = 0.032). CVD/MI/CIE occurred in 14 (15.5%) out of 90 follow-up patients. Multivariate Cox and ROC analysis showed associations between miR-1-3p and CVD (AUC = 0.634; HR = 4.84; 95% CI: 1.62–14.5; p = 0.005), MI (AUC = 0.743; HR = 7.8; 95% CI: 2.01–30.0; p = 0.003), and CVD/MI/CIE (AUC = 0.560; HR = 4.6; 95% CI: 1.61–13.1; p = 0.004), while miR-133b was associated with recurrent CIE (AUC = 0.581; HR = 2.25; 95% CI: 1.01–5.02; p = 0.047).

Conclusions

A significant difference in levels of selected miRNAs is observed in symptomatic vs. asymptomatic ICAS. Plaque morphology and structure is associated with change of miRNA levels. The expression of miR-1-3p may be a potential prognostic factor for future cardiovascular events.

Role of microRNA in Development of Instability of Atherosclerotic Plaques

MicroRNAs are small noncoding single-stranded RNAs that regulate gene expression. Today, we see an increasing number of studies highlighting the important role of microRNAs in the development and progression of cardiovascular diseases caused by atherosclerotic lesions of arteries. We review the available scientific data on association of the expression of these biomolecules with instability of atherosclerotic plaques in animal models and humans. We made special emphasis on miR-21, -100, -127, -133, -143/145, -221/222, and -494 because they were analyzed in more than one study. We discuss the possibility of microRNAs using in the diagnosis and therapy of atherosclerosis and its complications.

MicroRNA-100 Suppresses Chronic Vascular Inflammation by Stimulation of Endothelial Autophagy

RATIONALE

The interaction of circulating cells within the vascular wall is a critical event in chronic inflammatory processes, such as atherosclerosis, but the control of the vascular inflammatory state is still largely unclear.

OBJECTIVE

This study was undertaken to characterize the function of the endothelial-enriched microRNA miR-100 during vascular inflammation and atherogenesis.

METHODS AND RESULTS

Based on a transcriptome analysis of endothelial cells after miR-100 overexpression, we identified miR-100 as a potent suppressor of endothelial adhesion molecule expression, resulting in attenuated leukocyte-endothelial interaction in vitro and in vivo as shown by flow cytometry and intravital imaging. Mechanistically, miR-100 directly repressed several components of mammalian target of rapamycin complex 1-signaling, including mammalian target of rapamycin and raptor, which resulted in a stimulation of endothelial autophagy and attenuated nuclear factor κB signaling in vitro and in vivo. In a low-density lipoprotein receptor-deficient atherosclerotic mouse model, pharmacological inhibition of miR-100 resulted in enhanced plaque lesion formation and a higher macrophage content of the plaque, whereas a systemic miR-100 replacement therapy had protective effects and attenuated atherogenesis, resulting in a decrease of plaque area by 45%. Finally, analysis of miR-100 expression in >70 samples obtained during carotid endarterectomy revealed that local miR-100 expression was inversely correlated with inflammatory cell content in patients.

CONCLUSIONS

In summary, we describe an anti-inflammatory function of miR-100 in the vascular response to injury and inflammation and identify an important novel modulator of mammalian target of rapamycin signaling and autophagy in the vascular system. Our findings of miR-100 as a potential protective anti-athero-miR suggest that the therapeutic replacement of this microRNA could be a potential strategy for the treatment of chronic inflammatory diseases, such as atherosclerosis, in the future.

microRNA profiling in atherosclerosis, diabetes, and migraine

microRNAs (miRNAs) are a broad group of endogenous small non-coding molecules that reduce the transcription of mRNA and play a key role in post-transcriptional gene processes. miRNAs are involved in onset and progression of several human disorders such as infectious and immune non-infectious diseases, cancers, metabolic and cardiovascular disorders. They regulate the expression of gene targets (e.g. oncogenes and tumor suppressor genes) and act as gene repressors with mRNA binding and cleavage. The increasing evidence that miRNAs play a key role in the pathogenesis of cardiovascular conditions could radically change the future management approach to these disorders. This review focuses on current knowledge about the influence of miRNAs on cardiovascular disease, with particular regard to common conditions such as atherosclerosis, diabetes and migraine. Key messages miRNAs are a group of endogenous small non-coding RNA segments measuring 19-25 nucleotides that are involved in physiologic processes and onset and progression of disorders such as infectious and immune non-infectious diseases, cancers, metabolic and cardiovascular disorders. miRNAs expression guarantees vascular integrity, by regulating apoptosis, VEGF pathway and VCAM 1 expression (-126), and is involved in atherosclerotic plaque formation process and progression. Hyperglycemia, overt diabetes, and their complications are associated with overexpression of several miRNAs. An altered expression of miRNAs has also been postulated in migraine patients, although only a few preliminary studies have so far been performed with this respect.

Differential Expression of MicroRNAs in Endarterectomy Specimens Taken from Patients with Asymptomatic and Symptomatic Carotid Plaques

Objective

Stroke and transient ischemic attacks are considered as clinical manifestations of atherosclerotic disease due to on-going vascular inflammation and finally atherothrombosis of the carotid arteries. MicroRNAs (miRNA/miR) are known to be involved in vascular inflammation and plaque destabilization. The aim of this study was to analyze the expression profile of selected miRNAs in endarterectomy specimen from carotid arteries that were taken from patients with asymptomatic and symptomatic atherosclerotic plaques.

Methods and Results

11 miRNAs were selected and their expression was analyzed using real-time RT-PCR. Therefore, samples were divided into three different groups. On the one hand we investigated the expression patterns from patients in asymptomatic (n = 14) and symptomatic (n = 10) plaques; on the other hand we took samples from normal configurated internal mammary arteries (n = 15). Out of these 11 targets we identified some miRNAs, which were up- or down-regulated in either one of the two groups. Interestingly, the expression of two miRNAs was significantly different between asymptomatic and symptomatic samples, namely miR-21 (P<0.01) and miR-143 (P<0.05).

Conclusion

In the present study, we identified miRNA subtypes which showed different expression in endarterectomy specimen from patients with asymptomatic and symptomatic plaques, suggesting that these miRNAs correlated with advanced vascular inflammation and plaque stability. They may represent new therapeutic targets for vascular proliferative diseases such as atherosclerosis.

Inflammatory Biomarkers and Atherosclerosis

Atherosclerosis has been regarded as a form of chronic vascular inflammation. Numerous biomarkers associated with inflammation have been identified as novel targets to monitor atherosclerosis and cardiovascular risk. C-reactive protein (CRP) is one of the most actively studied and established inflammatory biomarkers for cardiovascular events. However, CRP response is triggered by many disorders unrelated to cardiovascular disease, which interferes with the clinical application. This review describes established and traditional inflammatory biomarkers including CRP as well as novel inflammatory biomarkers reflective of local atherosclerotic inflammation. In addition, we focus on the potential usefulness of inflammatory biomarkers in developing anti-atherosclerotic therapeutic approaches.