Increased Expression of miR-146a in Valvular Tissue From Patients With Aortic Valve Stenosis

Potential Roles of microRNAs for Assessing Cardiovascular Risk in Pre-Eclampsia-Exposed Postpartum Women and Offspring

Pre-eclampsia, which is part of the spectrum of hypertensive pregnancy disorders, poses a significant health burden, contributing to maternal and infant morbidity and mortality. Pre-eclampsia is widely associated with persistent adverse effects on the cardiovascular health of women with a history of pre-eclampsia. Additionally, there is increasing evidence demonstrating that offspring of pre-eclamptic pregnancies have altered cardiac structure and function, as well as different vascular physiology due to the decrease in endothelial function. Therefore, early detection of the likelihood of developing pre-eclampsia-associated cardiovascular diseases is vital, as this could facilitate the undertaking of the necessary clinical measures to avoid disease progression. The utilisation of microRNAs as biomarkers is currently on the rise as microRNAs have been found to play important roles in regulating various physiological and pathophysiological processes. In regard to pre-eclampsia, recent studies have shown that the expression of microRNAs is altered in postpartum women and their offspring who have been exposed to pre-eclampsia, and that these alterations may persist for several years. This review, therefore, addresses changes in microRNA expression found in postpartum women and offspring exposed to pre-eclampsia, their involvement in cardiovascular disease, and the potential role of microRNAs to be used as predictive tools and therapeutic targets in future cardiovascular disease research.

The Role of MicroRNAs in Aortic Stenosis-Lessons from Recent Clinical Research Studies

Aortic stenosis (AS) is the most prevalent primary valve lesion demanding intervention. Two main treatment options are surgical aortic valve replacement or transcatheter aortic valve implantation. There is an unmet need for biomarkers that could predict treatment outcomes and become a helpful tool in guiding Heart Team in the decision-making process. Micro-ribonucleic acids (microRNAs/miRs) have emerged as potential biomarkers thoroughly studied in recent years. In this review, we aimed to summarize the current knowledge about the role of miRNAs in AS based on human subject research. Much research investigating miRNAs' role in AS has been conducted so far. We included 32 original human subject research relevant to the discussed field. Most of the presented miRNAs were studied only by a single research group. Nevertheless, several miRNAs appeared more than once, sometimes with high consistency between different studies but sometimes with apparent discrepancies. The molecular aspects of diseases are doubtlessly exciting and provide invaluable insights into the pathophysiology. Nevertheless, translating these findings, regarding biomarkers such as miRNAs, into clinical practice requires much effort, time, and further research with a focus on validating existing evidence.

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.

Vaccine Formulation Strategies and Challenges Involved in RNA Delivery for Modulating Biomarkers of Cardiovascular Diseases: A Race from Laboratory to Market

It has been demonstrated that noncoding RNAs have significant physiological and pathological roles. Modulation of noncoding RNAs may offer therapeutic approaches as per recent findings. Small RNAs, mostly long noncoding RNAs, siRNA, and microRNAs make up noncoding RNAs. Inhibiting or promoting protein breakdown by binding to 3' untranslated regions of target mRNA, microRNAs post-transcriptionally control the pattern of gene expression. Contrarily, long non-coding RNAs perform a wider range of tasks, including serving as molecular scaffolding, decoys, and epigenetic regulators. This article provides instances of long noncoding RNAs and microRNAs that may be a biomarker of CVD (cardiovascular disease). In this paper we highlight various RNA-based vaccine formulation strategies designed to target these biomarkers-that are either currently in the research pipeline or are in the global pharmaceutical market-along with the physiological hurdles that need to be overcome.

miR-146a contributes to atherosclerotic plaque stability by regulating the expression of TRAF6 and IRAK-1

BACKGROUND

Atherosclerosis is a chronic inflammatory disease. The vulnerable plaque of atherosclerotic can lead to the development of many diseases including acute coronary syndrome and coronary heart disease. It is well known that miR-146a is the key brake miRNA of the inflammatory signal transduction pathway. However, the effect of miR-146a on the stability of atherosclerotic plaque remains to be elucidated.

METHODS AND RESULTS

We constructed animal models of atherosclerosis and foam cell models, and overexpressed and knocked-down miR-146a in models. After staining with Hematoxylin-Eosin (HE), Oil Red O, immunocytochemistry (IHC) and Sirius Red, we used the proportion of (Lipids area + Macrophage area) and (SMCs area + collagen area) to evaluate atherosclerotic plaque stability. TUNEL and flow cytometry were performed to detect the apoptosis level of macrophages. Levels of inflammatory factors were detected via ELISA assay. The results showed that miR-146a, IRAK1 and TRAF6 were abnormally expressed in plaques of atherosclerotic animals. Overexpression of miR-146a contributed to the stability of plaques that inhibited plaque formation, macrophage apoptosis and levels of pro-inflammatory factors. The Dual-luciferase reporter gene assay, IF and FISH were used to verify the regulatory mechanism of miR-146a on IRAK1 and TRAF6. We found that IRAK1 and TRAF6 promoted lipid uptake, apoptosis, and release of pro-inflammatory factors of RAW264.7 macrophages, whereas miR-146a restored RAW264.7 macrophages phenotype by inhibiting IRAK1 and TRAF6 expression.

CONCLUSIONS

We display for the first time that miR-146a inhibits the formation of foam cells, RAW264.7 macrophage apoptosis and pro-inflammatory reaction through negative regulation of IRAK1 and TRAF6 expression, thereby enhancing the stability of atherosclerotic plaques.

MicroRNA-146a-3p/HDAC1/KLF5/IKBα signal axis modulates plaque formation of atherosclerosis mice

BACKGROUND

Atherosclerosis (AS) is a multifocal, smoldering immune inflammatory disease of medium and large arteries driven by lipids. The aim of this study is to discuss the mechanism of microRNA-146a-3p (miR-146a-3p)/histone deacetylase 1 (HDAC1)/Krüppel-like factor 5 (KLF5)/inhibitors of kappa B α (IKBα) signal axis in plaque formation of AS mice.

METHODS

ApoE-/- mice were fed with high-fat feed for 12 weeks to establish AS mice model. The expression of miR-146a-3p, KLF5, HDAC1 and IKBα in aortic wall tissues of AS mice was tested. The targeting relationship between miR-146a-3p and HDAC1 was verified. AS mice were injected with miR-146a-3p antagomir or HDAC1 overexpression to verify the impacts of miR-146a-3p and HDAC1 on blood lipids and inflammatory factors in serum, aortic wall apoptotic cells, antioxidant stress capacity and the plaque area in AS mice. VECs proliferation and apoptosis were also measured in vitro.

RESULTS

miR-146a-3p and KLF5 were increased while HDAC1 and IKBα were reduced in aortic wall tissues of AS mice. miR-146a-3p directly targeted to HDAC1. Depletion of miR-146a-3p or restoration of HDAC1 was correlated to lower plasma lipid level, reduced inflammatory factors in serum, attenuated aortic wall apoptosis, increased antioxidant stress capacity and improved the stability of pathological plaque of AS mice. miR-146a-3p down-regulation or HDAC1 up-regulation promoted VECs proliferation and inhibited apoptosis.

CONCLUSION

Functional studies show that depleted miR-146a-3p advances HDAC1 and IKBα expression as well as inhibits KLF5 expression to facilitate the stability of pathological plaques in AS mice.

Oxidized LDL-regulated microRNAs for evaluating vascular endothelial function: molecular mechanisms and potential biomarker roles in atherosclerosis

As a simple monolayer, vascular endothelial cells can respond to physicochemical stimuli. In addition to promoting the formation of foam cells, oxidized low-density lipoprotein (ox-LDL) contributes to the atherosclerotic process through different mechanisms, including endothelial cell dysfunction. As conserved noncoding RNAs, microRNAs (miRNAs) naturally lie in different genomic positions and post-transcriptionally regulate the expression of many genes. They participate in integrated networks formed under stress to maintain cellular homeostasis, vascular inflammation, and metabolism. These small RNAs constitute therapeutic targets in different diseases, including atherosclerosis, and their role as biomarkers is crucial given their detectability even years before the emergence of diseases. This review was performed to investigate the role of ox-LDL-regulated miRNAs in atherosclerosis, their molecular mechanisms, and their application as biomarkers of vascular endothelial cell dysfunction.

Adding a "Notch" to Cardiovascular Disease Therapeutics: A MicroRNA-Based Approach

Dysregulation of the Notch pathway is implicated in the pathophysiology of cardiovascular diseases (CVDs), but, as of today, therapies based on the re-establishing the physiological levels of Notch in the heart and vessels are not available. A possible reason is the context-dependent role of Notch in the cardiovascular system, which would require a finely tuned, cell-specific approach. MicroRNAs (miRNAs) are short functional endogenous, non-coding RNA sequences able to regulate gene expression at post-transcriptional levels influencing most, if not all, biological processes. Dysregulation of miRNAs expression is implicated in the molecular mechanisms underlying many CVDs. Notch is regulated and regulates a large number of miRNAs expressed in the cardiovascular system and, thus, targeting these miRNAs could represent an avenue to be explored to target Notch for CVDs. In this Review, we provide an overview of both established and potential, based on evidence in other pathologies, crosstalks between miRNAs and Notch in cellular processes underlying atherosclerosis, myocardial ischemia, heart failure, calcification of aortic valve, and arrhythmias. We also discuss the potential advantages, as well as the challenges, of using miRNAs for a Notch-based approach for the diagnosis and treatment of the most common CVDs.

Genetics of macrovascular complications in type 2 diabetes

Type 2 diabetes mellitus (T2DM) is a metabolic disorder that currently affects more than 400 million worldwide and is projected to cause 552 million cases by the year 2030. Long-term vascular complications, such as coronary artery disease, myocardial infarction, stroke, are the leading causes of morbidity and mortality among diabetic patients. The recent advances in genome-wide technologies have given a powerful impetus to the study of risk markers for multifactorial diseases. To date, the role of genetic and epigenetic factors in modulating susceptibility to T2DM and its vascular complications is being successfully studied that provides the accumulation of genomic knowledge. In the future, this will provide an opportunity to reveal the pathogenetic pathways in the development of the disease and allow to predict the macrovascular complications in T2DM patients. This review is focused on the evidence of the role of genetic variants and epigenetic changes in the development of macrovascular pathology in diabetic patients.

microRNAs involved in psoriasis and cardiovascular diseases

Psoriasis is a chronic inflammatory disease involving the skin. Both genetic and environmental factors play a pathogenic role in psoriasis and contribute to the severity of the disease. Psoriasis, in fact, has been associated with different comorbidities such as diabetes, metabolic syndrome, gastrointestinal or kidney diseases, cardiovascular disease (CVD), and cerebrovascular diseases (CeVD). Indeed, life expectancy in severe psoriasis is reduced by up to 5 years due to CVD and CeVD. Moreover, patients with severe psoriasis have a higher prevalence of traditional cardiovascular (CV) risk factors, including dyslipidemia, diabetes, smoking, and hypertension. Further, systemic inflammation is associated with oxidative stress increase and induces endothelial damage and atherosclerosis progression. Different miRNA have been already described in psoriasis, both in the skin tissues and in the blood flow, to play a role in the progression of disease. In this review, we will summarize and discuss the most important miRNAs that play a role in psoriasis and are also linked to CVD.

miR-146a in Cardiovascular Diseases and Sepsis: An Additional Burden in the Inflammatory Balance?

The new concept of thrombosis associated with an inflammatory process is called thromboinflammation. Indeed, both thrombosis and inflammation interplay one with the other in a feed forward manner amplifying the whole process. This pathological reaction in response to a wide variety of sterile or non-sterile stimuli eventually causes acute organ damage. In this context, neutrophils, mainly involved in eliminating pathogens as an early barrier to infection, form neutrophil extracellular traps (NETs) that are antimicrobial structures responsible of deleterious side effects such as thrombotic complications. Although NETosis mechanisms are being unraveled, there are still many regulatory elements that have to be discovered. Micro-ribonucleic acids (miRNAs) are important modulators of gene expression implicated in human pathophysiology almost two decades ago. Among the different miRNAs implicated in inflammation, miR-146a is of special interest because: (1) it regulates among others, Toll-like receptors/nuclear factor-κB axis which is of paramount importance in inflammatory processes, (2) it regulates the formation of NETs by modifying their aging phenotype, and (3) it has expression levels that may decrease among individuals up to 50%, controlled in part by the presence of several polymorphisms. In this article, we will review the main characteristics of miR-146a biology. In addition, we will detail how miR-146a is implicated in the development of two paradigmatic diseases in which thrombosis and inflammation interact, cardiovascular diseases and sepsis, and their association with the presence of miR-146a polymorphisms and the use of miR-146a as a marker of cardiovascular diseases and sepsis.

Increased plasma miR-146a levels are associated with subclinical atherosclerosis in newly diagnosed type 2 diabetes mellitus

AIMS

The association between circulating miR-146a and subclinical atherosclerosis in type 2 diabetes mellitus (T2DM) remains poorly understood. This study aimed to investigate the correlation between plasma miR-146a levels and subclinical atherosclerosis as measured by the carotid intima-media thickness (CIMT) and brachial-ankle pulse wave velocity (baPWV) in patients with newly diagnosed T2DM.

METHODS

We studied 100 patients with newly diagnosed T2DM. Subclinical atherosclerosis was defined as a thickened CIMT (≥1.0 mm) and high baPWV defined as a value greater than the 75th percentile. Plasma miR-146a levels and metabolic parameters were measured.

RESULTS

Patients with thickened CIMT had higher plasma miR-146a levels than those without thickened CIMT (3.36 ± 1.32 vs 1.38 ± 1.11, P < 0.001). Patients in the high baPWV group had higher plasma miR-146a levels than those in the normal baPWV group (3.43 ± 1.32 vs 1.98 ± 1.48, P < 0.001). Both CIMT (β = 0.569, P < 0.001) and baPWV (β = 0.274, P = 0.001) positively correlated with plasma miR-146a levels after adjustment for confounding factors by multiple stepwise regression. On binary logistic regression, plasma miR-146a level was an independent risk factor for thickened CIMT (OR = 3.890, 95% CI 1.415-7.698, P = 0.008) and high baPWV (OR = 1.954, 95% CI 1.256-3.040, P = 0.002) after adjustment for established cardiovascular risk factors. The area under the receiver operating characteristics curve (AUROC) of plasma miR-146a level for predicting thickened CIMT was 0.795 (95%CI 0.708-0.883, P < 0.001) and for predicting high baPWV was 0.773 (95%CI 0.679-0.867, P < 0.001).

CONCLUSION

Plasma miR-146a levels correlate with CIMT and baPWV and could act as a biomarker for early diagnosis and as a therapeutic target for atherosclerosis in T2DM.

MicroRNA-204 Deficiency in Human Aortic Valves Elevates Valvular Osteogenic Activity

Aortic valve interstitial cells (AVICs) play a major role in valvular calcification associated with calcific aortic valve disease (CAVD). Although AVICs from diseased valves display a pro-osteogenic phenotype, the underlying mechanism causing this remains unclear. MicroRNA-204 (miR-204) is a negative regulator of osteoblast differentiation. We sought to analyze miR-204 expression in diseased human aortic valves and determine the role of this miR in AVIC osteogenic activity associated with CAVD pathobiology. In situ hybridization and PCR analysis revealed miR-204 deficiency in diseased valves and in AVICs from diseased valves. MiR-204 mimic suppressed alkaline phosphatase (ALP) expression and calcium deposition in AVICs from diseased valves. MiR-204 antagomir enhanced ALP expression in AVICs from normal valves through induction of Runx2 and Osx, and expression of miR-204 antagomir in mouse aortic valves promoted calcium deposition through up-regulation of Runx2 and Osx. Further, miR-204 mimic suppressed the osteogenic responses to TGF-β1 in AVICs of normal valves. In conclusion, miR-204 deficiency contributes to the mechanism underlying elevated osteogenic activity in diseased aortic valves, and miR-204 is capable of reversing the pro-osteogenic phenotype of AVICs of diseased valves and suppressing AVIC osteogenic response to stimulation. Exogenous miR-204 may have therapeutic potential for inhibiting valvular calcification associated with CAVD progression.