miRNA polymorphisms (miR-146a, miR-149, miR-196a2 and miR-499) are associated with the risk of coronary artery disease

Genetic and Epigenetic Regulation of Lipoxygenase Pathways and Reverse Cholesterol Transport in Atherogenesis

Atherosclerosis is one of the most important medical and social problems of modern society. Atherosclerosis causes a large number of hospitalizations, disability, and mortality. A considerable amount of evidence suggests that inflammation is one of the key links in the pathogenesis of atherosclerosis. Inflammation in the vascular wall has extensive cross-linkages with lipid metabolism, and lipid mediators act as a central link in the regulation of inflammation in the vascular wall. Data on the role of genetics and epigenetic factors in the development of atherosclerosis are of great interest. A growing body of evidence is strengthening the understanding of the significance of gene polymorphism, as well as gene expression dysregulation involved in cross-links between lipid metabolism and the innate immune system. A better understanding of the genetic basis and molecular mechanisms of disease pathogenesis is an important step towards solving the problems of its early diagnosis and treatment.

The association of plasma levels of miR-146a, miR-27a, miR-34a, and miR-149 with coronary artery disease

BACKGROUND

Coronary artery disease (CAD) is considered to be one of the most pivotal causes of death in the world. Over the past two decades, significant changes occurred in the diagnosis, prognosis, and treatment of CAD, which has helped reduce mortality rates. microRNAs (miRs) are a class of more than 5000 non-encoding RNA molecules (21-25 nucleotides across the length) that regulate complex biological processes. Today, miRNAs are used to study cardiovascular diseases. In the present study, the expression of miR-146a،miR-27, miR-149, and miR-34a in plasma suffering from CAD and the control group were investigated.

METHODS AND RESULTS

The present research was performed on 30 men with CAD and 30 healthy men as controls. The expression levels of miR-146a, miR-27a, miR-149, and miR-34a in the plasma of patients with CAD and the control group were measured using real-time PCR. Also, the correlation between the expression of circulating miRs levels and biochemical LDL-C, HDL-C, BMI, and total cholesterol was evaluated. The expression of miR-27a in the plasma of the CAD group was higher than in the control group (p = 0.020). The expression of miR-146a was downregulated in CAD patients compared to normal subjects (p = 0. 026). However, the expression of miR-34a, miR-149 in the plasma of CAD patients was not significantly different with the control group. In addition to, a direct correlation was found between the expression of miR-146a and HDL-c, the expression of miR-27a and LDL-C and the expression of miR-34a and total cholesterol. Also, the negative correlation between expressions of miR-149 with BMI was reported.

CONCLUSION

The obtained results demonstrated that miRs were closely related to biochemical factors and it points out the fact that miRNAs can be applied as a potential strategy for diagnosis and treatment of CAD.

Differential impact of the angiotensin‑converting enzyme‑2 (ACE2 rs4343 G>A) and miR‑196a2 rs11614913 C>T gene alterations in COVID‑19 disease severity and mortality

The recent coronavirus outbreak from Wuhan China in late 2019 caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) resulted in a global pandemic of coronavirus-19 disease (COVID-19). Understating the underlying mechanism of the pathogenesis of coronavirus infection is important not only because it will help in accurate diagnosis and treatment of the infection but also in the production of effective vaccines. The infection begins when SARS-CoV-2 enters the cells through binding of its envelope glycoprotein to angiotensin-converting enzyme2 (ACE2). Gene variations of ACE2 and microRNA (miR)-196 are associated with viral infection and other diseases. The present study investigated the association of the ACE2 rs4343 G>A and miR-196a2 rs11614913 C>T gene polymorphisms with severity and mortality of COVID-19 using amplification refractory mutation system PCR in 117 COVID-19 patients and 103 healthy controls from three regions of Saudi Arabia. The results showed that ACE2 rs4343 GA genotype was associated with severity of COVID-19 (OR=2.10, P-value 0.0028) and ACE2 rs4343 GA was associated with increased mortality with OR=3.44, P-value 0.0028. A strong correlation between the ACE2 rs4343 G>A genotype distribution among COVID-19 patients was reported with respect to their comorbid conditions including sex (P<0.023), coronary artery disease (P<0.0001), oxygen saturation <60 mm Hg (P<0.0009) and antiviral therapy (0.003). The results also showed that the CT genotype and T allele of the miR-196a2 rs11614913 C>T were associated with decreased risk to COVID-19 with OR=0.76, P=0.006 and OR=0.54, P=0.005, respectively. These results need to be validated with future molecular genetic studies in a larger sample size and different populations.

Clinical Implications of Krüpple-like Transcription Factor KLF-14 and Certain Micro-RNA (miR-27a, miR-196a2, miR-423) Gene Variations as a Risk Factor in the Genetic Predisposition to PCOS

Polycystic ovary syndrome (PCOS) is a disorder with a symptomatic manifestation of an array of metabolic and endocrine impairments. PCOS has a relatively high prevalence rate among young women of reproductive age and is a risk factor for some severe metabolic diseases such as T2DM, insulin insensitivity, and obesity, while the most dominant endocrine malfunction is an excess of testosterone showing hyperandrogenism and hirsutism. MicroRNAs have been implicated as mediators of metabolic diseases including obesity and insulin resistance, as these can regulate multiple cellular pathways such as insulin signaling and adipogenesis. Genome-wide association studies during the last few years have also linked the Krüpple-like family of transcription factors such as KLF14, which contribute in mechanisms of mammalian gene regulation, with certain altered metabolic traits and risk of atherosclerosis and type-2 DM. This study has characterized the biochemical and endocrine parameters in PCOS patients with a comprehensive serum profiling in comparison to healthy controls and further examined the influence of allelic variations for miRNAs 27a (rs895819 A > G), 196a2 (rs11614913 C > T), 423 (rs6505162C > A), and transcription factor KLF14 (rs972283 A > G) gene polymorphism on the risk and susceptibility to PCOS. The experimental protocol included amplification refractory mutation-specific (ARMS)-PCR to detect and determine the presence of these polymorphic variants in the study subjects. The results in this case−control study showed that most of the serum biomarkers, both biochemical and endocrine, that were analyzed in the study demonstrated statistically significant alterations in PCOS patients, including lipids (LDL, HDL, cholesterol), T2DM markers (fasting glucose, free insulin, HOMA-IR), and hormones (FSH, LH, testosterone, and progesterone). The distribution of Krüppel-like factor 14 rs972283 G > A, miR-27a rs895819 A > G, and miR-196a-2 rs11614913 C > T genotypes analyzed within PCOS patients and healthy controls in the considered population was significant (p < 0.05), except for miR-423 rs6505162 C > A genotypes (p > 0.05). The study found that in the codominant model, KLF14-AA was strongly associated with greater PCOS susceptibility (OR 2.35, 95% CI = 1.128 to 4.893, p < 0.022), miR-27a-GA was linked to an enhanced PCOS susceptibility (OR 2.06, 95% CI = 1.165 to 3.650, p < 0.012), and miR-196a-CT was associated with higher PCOS susceptibility (OR 2.06, 95% CI = 1.191 to 3.58, p < 0.009). Moreover, allele A of KLF-14 and allele T of miR-196a2 were strongly associated with PCOS susceptibility in the considered population.

Potential impact of GCK, MIR-196A-2 and MIR-423 gene abnormalities on the development and progression of type 2 diabetes mellitus in Asir and Tabuk regions of Saudi Arabia

Type 2 diabetes mellitus (T2DM) is a metabolic disorder characterized by persistent hyperglycemia and is associated with serious complications. The risk factors for T2DM include both genetic and lifestyle factors. Genome-wide association studies have indicated the association of genetic variations with many diseases, including T2DM. Glucokinase (GCK) plays a key role in the regulation of insulin release in the pancreas and catalyzes the first step in glycolysis in the liver. Genetic alterations in the GCK gene have been implicated in both hyperglycemia and hypoglycemia. MicroRNAs (miRNAs/miRs) are small non-coding RNA molecules that are involved in the important physiological processes including glucose metabolism. In the present study, the association of the single nucleotide polymorphisms (SNPs) in the GCK, MIR-196A-2 and MIR-423 genes with susceptibility to T2DM in patients from two regions of Saudi Arabia were examined, using the tetra-primer amplification refractory mutation system. The results showed that the AA genotype and the A allele of GCK rs1799884 were associated with T2DM [odds ratio (OR)=2.25, P=0.032 and OR=1.55, P=0.021, respectively]. Likewise, the CT genotype and T allele of MIR-196A-2 rs11614913 were associated with an increased risk of T2DM (OR=2.36, P=0.0059 and OR=1.74, P=0.023, respectively). In addition, the CA genotype of MIR-423 rs6505162 C>A was found to be linked with T2DM (OR=2.12 and P=0.021). It was concluded in the present research study that gene variations in GCK, MIR-196A-2 and MIR-423 are potentially associated with an increased risk of T2DM. These results, in the future, may help in the identification and stratification of individuals susceptible to T2DM. Future longitudinal studies with larger sample sizes and in different ethnic populations are recommended to validate these findings.

Multilayer control of cardiac electrophysiology by microRNAs

The electrophysiological properties of the heart include cardiac automaticity, excitation (i.e., depolarization and repolarization of action potential) of individual cardiomyocytes, and highly coordinated electrical propagation through the whole heart. An abnormality in any of these properties can cause arrhythmias. MicroRNAs (miRs) have been recognized as essential regulators of gene expression through the conventional RNA interference (RNAi) mechanism and are involved in a variety of biological events. Recent evidence has demonstrated that miRs regulate the electrophysiology of the heart through fine regulation by the conventional RNAi mechanism of the expression of ion channels, transporters, intracellular Ca²⁺-handling proteins, and other relevant factors. Recently, a direct interaction between miRs and ion channels has also been reported in the heart, revealing a biophysical modulation by miRs of cardiac electrophysiology. These advanced discoveries suggest that miR controls cardiac electrophysiology through two distinct mechanisms: immediate action through biophysical modulation and long-term conventional RNAi regulation. Here, we review the recent research progress and summarize the current understanding of how miR manipulates the function of ion channels to maintain the homeostasis of cardiac electrophysiology.

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 polymorphism is not associated with cardiovascular disease in the elderly

Abstract Introduction: Cardiovascular diseases (CVD) figure among the most significant causes of morbidity and mortality in the world and, among genetic factors, the literature has demonstrated the crucial role of miRNAs and the relationship of physical activity with this pathology. Objective: To investigate the relationship between the functional capacity of exercise, the level of physical activity, and the polymorphism in the miRNA-146a gene in elderly individuals with and without CVD. Methods: This study, developed in a city in the southern region of Brazil, is characterized as cross-sectional. The sample for this study comprised 342 participants, aged 60 or over. The following aspects were analyzed: anthropometric characteristics, genetic profiles, diagnosis of CVD, functional capacity, and the level of physical activity. Results: A statistically significant association was observed between CVD and body mass index (BMI) (א² = 14.278; p = 0.0003), and 40.6% of elderly individuals with CVD were obese, while 31.5% of the normally developed elderly participants presented normal BMI. However, the genotype frequencies (p = 0.546; א² = 1.211) and 6MWT (p = 0.311; א² = 1.025) did not show a statistically signifi-cant association with CVD. Conclusion: Our results suggest that the polymorphism in the miRNA-146A (rs2910164) and functional capacity are not associated with CVD in the elderly. However, the BMI did demonstrate an association with this disease.

Association study of miR-149, miR-196a2, and miR-499a polymorphisms with coronary artery aneurysm of Kawasaki disease in southern Chinese population

Background

Accumulating evidence suggests that several microRNA (miRNA) polymorphisms are closely associated with disease susceptibility or progression, such as in Kawasaki disease (KD). Our previous studies revealed the association of miR‐149 rs2292832 T>C and miR‐196a2 rs11614913 C>T polymorphisms with KD susceptibility. The present study further focused on the relationship between three miRNA polymorphisms (miR‐149 rs2292832 T>C, miR‐196a2 rs11614913 C>T and miR‐499a rs3746444 A>G) and the risk of coronary artery aneurysm (CAA) in southern Chinese KD patients.

Methods

We evaluated 318 KD patients with CAAs and 784 patients without CAAs. TaqMan assays were used to estimate genotyping and analyze the relationship between miRNA polymorphisms (miR‐149 rs2292832 T>C, miR‐196a2 rs11614913 C>T and miR‐499a rs3746444 A>G) and risk associations of CAA by odds ratios (ORs) and 95% confidence intervals (CIs).

Results

We found that the miR‐149 rs2292832 TC/CC genotype increased the CAA risk (adjusted OR = 1.53, 95% CI = 1.15–2.03, p = 0.003 for TC, adjusted OR = 1.63, 95% CI = 1.08–2.47, p = 0.021 for CC), whereas the miR‐499a rs3746444 AG genotype decreased the CAA risk in KD patients (adjusted OR = 0.33, 95% CI = 0.25–0.45 p ≤ 0.001). Moreover, patients carrying two or three of these single nucleotide polymorphism (SNP) genotypes (rs2292832 TC/CC and rs11614913 TT and rs3746444 AA) had a higher risk for CAA than those who harbored only zero or one of these SNP genotypes.

Conclusions

Our results demonstrated that the miR‐149 rs2292832 T>C polymorphism increased the risk of CAA in KD patients and that the miR‐499a rs3746444 A>G polymorphism decreased the risk of CAA in KD patients. Further studies with larger sample sizes and different centers are needed to confirm the findings of the present study.

Biomarkers in the clinical management of patients with atrial fibrillation and heart failure

Atrial fibrillation (AF) and heart failure (HF) are two cardiovascular diseases with an increasing prevalence worldwide. These conditions share common pathophysiologiesand frequently co-exit. In fact, the occurrence of either condition can 'cause' the development of the other, creating a new patient group that demands different management strategies to that if they occur in isolation. Regardless of the temproral association of the two conditions, their presence is linked with adverse cardiovascular outcomes, increased rate of hospitalizations, and increased economic burden on healthcare systems. The use of low-cost, easily accessible and applicable biomarkers may hasten the correct diagnosis and the effective treatment of AF and HF. Both AF and HF effect multiple physiological pathways and thus a great number of biomarkers can be measured that potentially give the clinician important diagnostic and prognostic information. These will then guide patient centred therapeutic management. The current biomarkers that offer potential for guiding therapy, focus on the physiological pathways of miRNA, myocardial stretch and injury, oxidative stress, inflammation, fibrosis, coagulation and renal impairment. Each of these has different utility in current clinincal practice.

In silico identification of variations in microRNAs with a potential impact on dairy traits using whole ruminant genome SNP datasets

MicroRNAs are small noncoding RNAs that have important roles in the lactation process and milk biosynthesis. Some polymorphisms have been studied in various livestock species from the perspective of pathology or production traits. To target variants that could be the causal variants of dairy traits, genetic variants of microRNAs expressed in the mammary gland or present in milk and localized in dairy quantitative trait loci (QTLs) were investigated in bovine, caprine, and ovine species. In this study, a total of 59,124 (out of 28 millions), 13,427 (out of 87 millions), and 4761 (out of 38 millions) genetic variants in microRNAs expressed in the mammary gland or present in milk were identified in bovine, caprine, and ovine species, respectively. A total of 4679 of these detected bovine genetic variants are located in dairy QTLs. In caprine species, 127 genetic variants are localized in dairy QTLs. In ovine species, no genetic variant was identified in dairy QTLs. This study leads to the detection of microRNA genetic variants of interest in the context of dairy production, taking advantage of whole genome data to identify microRNA genetic variants expressed in the mammary gland and localized in dairy QTLs.

The Role of microRNAs in the Development of Type 2 Diabetes Complications

MicroRNAs represent a class of small (19-25 nucleotides) single-strand pieces of RNA that are noncoding ones. They are synthesized by RNA polymerase II from transcripts that fold back on themselves. They mostly act as gene regulatory agents that pair with complementary sequences on mRNA and produce silencing complexes, which, in turn, suppress coding genes at a post-transcriptional level. There is now evidence that microRNAs may affect insulin secretion or insulin action, as they can alter pancreatic beta cells development, insulin production, as well as insulin signaling. Any molecular disorder that affects these pathways can deteriorate insulin resistance and lead to type 2 diabetes mellitus (T2DM) onset. Furthermore, the expression of several microRNAs is up- or down-regulated in the presence of diabetic microvascular complications (i.e., peripheral neuropathy, nephropathy, retinopathy, foot ulcers), as well as in patients with coronary heart disease, stroke, and peripheral artery disease. However, more evidence is needed, specifically regarding T2DM patients, to establish the use of such microRNAs as diagnostical biomarkers or therapeutic targets in daily practice.

MicroRNA Biophysically Modulates Cardiac Action Potential by Direct Binding to Ion Channel

BACKGROUND

MicroRNAs (miRs) play critical roles in regulation of numerous biological events, including cardiac electrophysiology and arrhythmia, through a canonical RNA interference mechanism. It remains unknown whether endogenous miRs modulate physiologic homeostasis of the heart through noncanonical mechanisms.

METHODS

We focused on the predominant miR of the heart (miR1) and investigated whether miR1 could physically bind with ion channels in cardiomyocytes by electrophoretic mobility shift assay, in situ proximity ligation assay, RNA pull down, and RNA immunoprecipitation assays. The functional modulations of cellular electrophysiology were evaluated by inside-out and whole-cell patch clamp. Mutagenesis of miR1 and the ion channel was used to understand the underlying mechanism. The effect on the heart ex vivo was demonstrated through investigating arrhythmia-associated human single nucleotide polymorphisms with miR1-deficient mice.

RESULTS

We found that endogenous miR1 could physically bind with cardiac membrane proteins, including an inward-rectifier potassium channel Kir2.1. The miR1-Kir2.1 physical interaction was observed in mouse, guinea pig, canine, and human cardiomyocytes. miR1 quickly and significantly suppressed IK1 at sub-pmol/L concentration, which is close to endogenous miR expression level. Acute presence of miR1 depolarized resting membrane potential and prolonged final repolarization of the action potential in cardiomyocytes. We identified 3 miR1-binding residues on the C-terminus of Kir2.1. Mechanistically, miR1 binds to the pore-facing G-loop of Kir2.1 through the core sequence AAGAAG, which is outside its RNA interference seed region. This biophysical modulation is involved in the dysregulation of gain-of-function Kir2.1-M301K mutation in short QT or atrial fibrillation. We found that an arrhythmia-associated human single nucleotide polymorphism of miR1 (hSNP14A/G) specifically disrupts the biophysical modulation while retaining the RNA interference function. It is remarkable that miR1 but not hSNP14A/G relieved the hyperpolarized resting membrane potential in miR1-deficient cardiomyocytes, improved the conduction velocity, and eliminated the high inducibility of arrhythmia in miR1-deficient hearts ex vivo.

CONCLUSIONS

Our study reveals a novel evolutionarily conserved biophysical action of endogenous miRs in modulating cardiac electrophysiology. Our discovery of miRs' biophysical modulation provides a more comprehensive understanding of ion channel dysregulation and may provide new insights into the pathogenesis of cardiac arrhythmias.

Role of MicroRNAs in the Pathogenesis of Coronary Artery Disease

Coronary artery disease (CAD) is the main reason of cardiovascular mortalities worldwide. This condition is resulted from atherosclerotic occlusion of coronary arteries. MicroRNAs (miRNAs) are implicated in the regulation of proliferation and apoptosis of endothelial cells, induction of immune responses and different stages of plaque formation. Up-regulation of miR-92a-3p, miR-206, miR-216a, miR-574-5p, miR-23a, miR-499, miR-451, miR-21, miR-146a, and a number of other miRNAs has been reported in CAD patients. In contrast, miR-20, miR-107, miR-330, miR-383-3p, miR-939, miR-4306, miR-181a-5p, miR-218, miR-376a-3p, and miR-3614 are among down-regulated miRNAs in CAD. Differential expression of miRNAs in CAD patients has been exploited to design diagnostic or prognostic panels for evaluation of CAD patients. We appraise the recent knowledge about the role of miRNAs in the development of diverse clinical subtypes of CAD.

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.

A study of associations between CUBN, HNF1A, and LIPC gene polymorphisms and coronary artery disease

The aim of this study was to identify novel genetic markers related to coronary artery disease (CAD) using a whole-exome sequencing (WES) approach and determine any associations between the selected gene polymorphisms and CAD prevalence. CUBN, HNF1A and LIPC gene polymorphisms related to CAD susceptibility were identified using WES screening. Possible associations between the five gene polymorphisms and CAD susceptibility were examined in 452 CAD patients and 421 control subjects. Multivariate logistic regression analyses indicated that the CUBN rs2291521GA and HNF1A rs55783344CT genotypes were associated with CAD (GG vs. GA; adjusted odds ratio [AOR] = 1.530; 95% confidence interval [CI] 1.113–2.103; P = 0.002 and CC vs. CT; AOR = 1.512; 95% CI 1.119–2.045; P = 0.007, respectively). The CUBN rs2291521GA and HNF1A rs55783344CT genotype combinations exhibited a stronger association with CAD risk (AOR = 2.622; 95% CI 1.518–4.526; P = 0.001). Gene-environment combinatorial analyses indicated that the CUBN rs2291521GA, HNF1A rs55783344CT, and LIPC rs17269397AA genotype combination and several clinical factors (fasting blood sugar (FBS), high-density lipoprotein (HDL), and low-density lipoprotein (LDL) levels) were associated with increased CAD risk. The CUBN rs2291521GA, HNF1A rs55783344CT, and LIPC rs17269397AA genotypes in conjunction with abnormally elevated cholesterol levels increase the risk of developing CAD. This exploratory study suggests that polymorphisms in the CUBN, HNF1A, and LIPC genes can be useful biomarkers for CAD diagnosis and treatment.

Peripheral Blood Mononuclear Cells Expression Levels of miR-196a and miR-100 in Coronary Artery Disease Patients

As a chronic inflammatory disease, coronary artery disease (CAD) is a common cause of death worldwide. Dysregulation of microRNA expression levels in peripheral blood mononuclear cells (PBMCs) may contribute to CAD and serve as a potential diagnostic biomarker. Here, we evaluated PBMC expression of two CAD-related inflammatory miRNAs, miR-196a and miR-100, in PBMCs of CAD patients with significant stenosis (CAD, n: 72), patients with insignificant coronary stenosis (ICAD, n: 30), and controls (n: 74) and checked whether they can segregate study groups. MiRNA expression was evaluated using the standard stem-loop RT-qPCR method. MiR-196a expression was downregulated in ICAD compared to CADs and healthy groups. MiR100 expression levels were not different between groups. The receiver operating characteristic (ROC) curve analysis acquainted that miR-196a expression levels in PBMC could segregate CAD individuals or any of its clinical manifestations (i.e. unstable angina, stable angina, acute myocardial infarction) from ICADs. In conclusion, this study reported a distinct miR-196a expression pattern in PBMCs of all patient groups and recommended a biomarker potential for miR-196a in discriminating ICADs from CADs or healthy controls.

An Intelligent Decision-Making Support System for the Detection and Staging of Prostate Cancer in Developing Countries

Most developing countries face huge challenges in the medical field; scarce medical resources and inadequate medical personnel will affect the development and stability of the society. Therefore, for most developing countries, the development of intelligent medical systems can greatly alleviate the social contradictions arising from this problem. In this study, a new data decision-making intelligent system for prostate cancer based on perceptron neural network is proposed, which mainly makes decisions by associating some relevant disease indicators and combining them with medical images. Through data collection, analysis and integration of medical data, as well as the disease detection and decision-making process, patients are given an auxiliary diagnosis and treatment, so as to solve the problems and social contradictions faced by most developing countries. Through the study of hospitalization information of more than 8,000 prostate patients in three hospitals, about 2,156,528 data items were collected and compiled for experiment purposes. Experimental data shows that when the patient base increases from 200 to 8,000, the accuracy of the machine-assisted diagnostic system will increase from 61% to 87%, and the doctor's diagnosis rate will be reduced to 81%. From the study, it is concluded that when the patient base reaches a certain number, the diagnostic accuracy of the machine-assisted diagnosis system will exceed the doctor's expertise. Therefore, intelligent systems can help doctors and medical experts treat patients more effectively.

A comprehensive review on miR-146a molecular mechanisms in a wide spectrum of immune and non-immune inflammatory diseases

MicroRNAs (miRNAs) are single-strand endogenous and non-coding RNA molecules with a length of about 22 nucleotides, which regulate genes expression, through modulating the translation and stability of their target mRNAs. miR-146a is one of the most studied miRNAs, due to its central role in immune system homeostasis and control of the innate and acquired immune responses. Accordingly, abnormal expression or function of miR-146a results in the incidence and progression of immune and non-immune inflammatory diseases. Its deregulated expression pattern and inefficient function have been reported in a wide spectrum of these illnesses. Based on the existing evidence, this miRNA qualifies as an ideal biomarker for diagnosis, prognosis, and activity evaluation of immune and non-immune inflammatory disorders. Moreover, much attention has recently been paid to therapeutic potential of miR-146a and several researchers have assessed the effects of different drugs on expression and function of this miRNA at diverse experimental, animal, besides human levels, reporting motivating results in the treatment of the diseases. Here, in this comprehensive review, we provide an overview of miR-146a role in the pathogenesis and progression of several immune and non-immune inflammatory diseases such as Rheumatoid arthritis, Systemic lupus erythematosus, Inflammatory bowel disease, Multiple sclerosis, Psoriasis, Graves' disease, Atherosclerosis, Hepatitis, Chronic obstructive pulmonary disease, etc., discuss about its eligibility for being a desirable biomarker for these disorders, and also highlight its therapeutic potential. Understanding these mechanisms underlies the selecting and designing the proper therapeutic targets and medications, which eventually facilitate the treatment process.

miRNA polymorphisms and risk of premature coronary artery disease

OBJECTIVE

Several microRNA (miRNA) polymorphisms have been associated with susceptibility to specific health disorders, including cardiovascular diseases. The aim of the present study was to investigate whether four well-studied miRNA polymorphisms in non-Caucasian populations, namely miR146a G>C (rs2910164), miR149 C>T (rs2292832), miR196a2 C>T (rs11614913) and miR499 A>G (rs3746444), contribute to the risk for the development of premature Coronary Artery Disease (CAD) in the Greek population.

METHODS

We used a case-control study to examine these associations in 400 individuals: 200 CAD patients [including a subgroup of myocardial infraction (MI) patients] and 200 healthy controls, all of Greek origin. MiRNA polymorphisms were genotyped using three different assays: Polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP), High resolution Melting (HRM) and Sanger sequencing.

RESULTS

Two of these polymorphisms, miR196a2 C>T (rs11614913) and miR499 A>G (rs3746444) were found to be strongly associated with increased risk for CAD (p=0.0388 and p=0.0013, respectively) and for MI (p=0.0281 and p=0.0273, respectively). Furthermore, miR146C-miR149C-miR196T-miR499G allele combination appeared to be significantly related to CAD (p=0.0185) and MI (p=0.0337) prevalence.

CONCLUSIONS

Our results suggest that at least two of the studied polymorphisms, miR196a2 C>T (rs11614913) and miR499 A>G (rs3746444), as well as the miR146C-miR149C-miR196T-miR499G allele combination could represent useful biomarkers of CAD and/or MI susceptibility in the Greek population. These special genetic characteristics, in combination with environmental factors and personal habits, might contribute to CAD and/or MI prevalence.

Association between the miRNA-149 rs2292832 T>C polymorphism and Kawasaki disease susceptibility in a southern Chinese population

Background

Kawasaki disease (KD), which is characterized by vasculitis, is prone to occur in patients under 5 years of age, has an ambiguous etiology, and displays coronary artery lesions as the chief complication. Previous studies have linked miRNA‐149 to cancers, and rs2292832 T>C is related to allergic diseases and inflammatory bowel disease, which both show immune system disorders and coronary artery disease. Therefore, we performed a study concentrating on the association between the miRNA‐149 rs2292832 T>C polymorphism and KD susceptibility.

Methods

The subjects enrolled were 532 children with KD and 623 controls. We used TaqMan real‐time PCR to obtain the genotypes of the rs2292832 T>C polymorphism.

Results

Ultimately, no significant association was found between the miRNA‐149 rs2292832 T>C polymorphism and KD susceptibility, even in stratification analysis.

Conclusion

Our results indicated that in southern Chinese patients, the miRNA‐149 rs2292832 T>C polymorphism did not affect KD susceptibility, which needs to be further confirmed.

Potential Impact of MicroRNA Gene Polymorphisms in the Pathogenesis of Diabetes and Atherosclerotic Cardiovascular Disease

MicroRNAs (miRNAs) are endogenous, small (18–23 nucleotides), non-coding RNA molecules. They regulate the posttranscriptional expression of their target genes. MiRNAs control vital physiological processes such as metabolism, development, differentiation, cell cycle and apoptosis. The control of the gene expression by miRNAs requires efficient binding between the miRNA and their target mRNAs. Genome-wide association studies (GWASs) have suggested the association of single-nucleotide polymorphisms (SNPs) with certain diseases in various populations. Gene polymorphisms of miRNA target sites have been implicated in diseases such as cancers, diabetes, cardiovascular and Parkinson’s disease. Likewise, gene polymorphisms of miRNAs have been reported to be associated with diseases. In this review, we discuss the SNPs in miRNA genes that have been associated with diabetes and atherosclerotic cardiovascular disease in different populations. We also discuss briefly the potential underlining mechanisms through which these SNPs increase the risk of developing these diseases.

miRNA Genetic Variants Alter Their Secondary Structure and Expression in Patients With RASopathies Syndromes

RASopathies are a group of rare genetic diseases caused by germline mutations in genes involved in the RAS–mitogen-activated protein kinase (RAS-MAPK) pathway. Whole-exome sequencing (WES) is a powerful approach for identifying new variants in coding and noncoding DNA sequences, including miRNAs. miRNAs are fine-tuning negative regulators of gene expression. The presence of variants in miRNAs could lead to malfunctions of regulation, resulting in diseases. Here, we identified 41 variants in mature miRNAs through WES analysis in five patients with previous clinical diagnosis of RASopathies syndromes. The pathways, biological processes, and diseases that were over-represented among the target genes of the mature miRNAs harboring variants included the RAS, MAPK, RAP1, and PIK3-Akt signaling pathways, neuronal differentiation, neurogenesis and nervous system development, congenital cardiac defects (hypertrophic cardiomyopathy, dilated cardiomyopathy, and arrhythmogenic right ventricular cardiomyopathy), and the phenotypes and syndromes of RASopathies (Noonan syndrome, Legius syndrome, Costello syndrome, Cafe au lait spots multiple, subaortic stenosis, pulmonary valve stenosis, and LEOPARD syndrome). Furthermore, eight selected variants in nine mature miRNAs (hsa-miR-1304, hsa-miR-146a, hsa-miR-196a2, hsa-miR-499a/hsa-miR-499b, hsa-miR-449b, hsa-miR-548l, hsa-miR-575, and hsa-miR-593) may have caused alterations in the secondary structures of miRNA precursor. Selected miRNAs containing variants such as hsa-miR-146a-3p, hsa-miR-196a-3p, hsa-miR-548l, hsa-miR-449b-5p, hsa-miR-575, and hsa-miR499a-3p could regulate classical genes associated with Rasopathies and RAS-MAPK pathways, contributing to modify the expression pattern of miRNAs in patients. RT-qPCR expression analysis revealed four differentially expressed miRNAs that were downregulated: miRNA-146a-3p in P1, P2, P3, P4, and P5, miR-1304-3p in P2, P3, P4, and P5, miR-196a2-3p in P3, and miR-499b-5p in P1. miR-499a-3p was upregulated in P1, P3, and P5. These results indicate that miRNAs show different expression patterns when these variants are present in patients. Therefore, this study characterized the role of miRNAs harboring variants related to RASopathies for the first time and indicated the possible implications of these variants for phenotypes of RASopathies such as congenital cardiac defects and cardio-cerebrovascular diseases. The expression and existence of miRNA variants may be used in the study of biomarkers of the RASopathies.

Associations Between microRNA Polymorphisms and Development of Coronary Artery Disease: A Case-Control Study

Coronary artery disease (CAD), a common cardiovascular disease, has become a vital cause of mortality worldwide. Genetic microRNA (miR) polymorphisms might contribute to CAD susceptibility. In this study, we selected miR-146a, miR-196a2, and miR-499 single nucleotide polymorphisms and conducted a case-control study. In total, 505 CAD cases and 1109 controls were recruited. We used SNPscan™ genotyping assay to obtain genotyping of miR rs2910164, rs11614913, and rs3746444 variants. We found that miR-196a2 rs11614913 T > C decreased the susceptibility of myocardial infarction (MI) (TC vs. TT: adjusted p = 0.007 and CC/TC vs. TT: adjusted p = 0.012). In female subgroup, our results indicated that miR-196a2 rs11614913 T > C variants might also decrease the susceptibility of CAD (TC vs. TT: adjusted p = 0.017 and TC/CC vs. TT: adjusted p = 0.015). In summary, these results suggest that miR-196a2 rs11614913 T > C locus decreases the susceptibility of CAD in female and MI subgroups. However, further studies are needed to validate the potential associations of miR-196a2 rs11614913 locus with CAD.

miR-149-5p Inhibits Vascular Smooth Muscle Cells Proliferation, Invasion, and Migration by Targeting Histone Deacetylase 4 (HDAC4)

BACKGROUND Studies have demonstrated that microRNAs (miRNAs) have essential roles in biological functions of vascular smooth muscle cells (VSMCs). However, the function and related molecular mechanism of miR-149-5p in VSMCs remains unclear. MATERIAL AND METHODS We used MTT assay, Transwell assay, and wound-healing assay to measure the proliferation, invasion, and migration of VSMCs transfected with miR-149-5p mimics or inhibitors, respectively. Bioinformatics tools and luciferase assay were used to validate the relationship between miR-149-5p and histone deacetylase 4 (HDAC4). Rescue experiments were used to confirm the interaction of miR-149-5p and HDAC4 in regulating biological functions in VSMCs. RESULTS miR-149-5p was downregulated in PDGF-bb-induced VSMCs. It was also found that miR-149-5p overexpression suppressed proliferation, invasion, and migration of VSMCs, while miR-149-5p knockdown showed the opposite effects. Furthermore, HDAC4 was found to be a potential target of miR-149-5p, which rescued miR-149-5p-mediated proliferation, invasion, and migration in VSMCs. CONCLUSIONS We demonstrated that miR-149-5p can suppress biological functions of VSMCs by regulating HDAC4, which might provide a potent therapeutic target for VSMC growth-related diseases.

Associations between miR-146a rs2910164 polymorphisms and risk of ischemic cardio-cerebrovascular diseases

BACKGROUND

Many studies investigated the association between miR-146a rs2910164 polymorphisms and risk of ischemic cardio-cerebrovascular diseases. However, the results were inconsistent.

METHODS

We searched the PubMed, EMBASE, Cochrane library, Web of Science, Chinese National Knowledge Infrastructure, VIP, and Wanfang databases for appropriate studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to evaluate the associations. Heterogeneity, sensitivity, and publication bias were conducted to measure the robustness of our findings.All analyses were based on previous published studies, thus, no ethical approval and patient consent are required.

RESULTS

We conducted a meta-analysis to evaluate the relationship between miR-146a rs2910164 polymorphisms and risk of ischemic cardio-cerebrovascular diseases. A total of 26 related studies involving 11,602 cases and 14,016 controls were identified and included in our meta-analysis. After considering the heterogeneity of the global analysis, we inferred that rs2910164 polymorphisms were associated with a lower risk of coronary heart disease (CHD) significantly in all genetic models. In addition, it was also found that the miR-146a rs2910164 polymorphisms were associated with the low risk of ischemic cardio-cerebrovascular diseases in large sample size subgroup analysis.

CONCLUSION

These results indicate that miR-146a rs2910164 polymorphisms were significantly associated with a lower risk of ischemic cardio-cerebrovascular. The miR-146a rs29101164 might be recommended as a predictor for susceptibility of ischemic cardio-cerebrovascular diseases.

MicroRNAs: Emerging biomarkers for atrial fibrillation

Atrial fibrillation (AF) causes severe cardiac dysrhythmia among patients with cardiovascular diseases. AF increases the risk of stroke and heart failure and is a growing public health concern. AF is also associated with various disease conditions such as hypertension, coronary artery disease, aging, and diabetes mellitus. The mechanism underlying AF is not completely understood due to its complexity. However, experimental and clinical data have revealed that the prevalence of this disease is associated with atrial arrhythmogenic remodeling. Currently, there are no biomarkers that are available for the early diagnosis of AF. Several studies have proposed microRNAs (miRNAs) as useful biomarkers for the diagnosis of AF due to their stability and easy availability both in atrial tissue and circulating blood. miRNAs play an important role in the development of the heart. The dysregulation of miRNA expression is associated with cardiac remodeling. Genetic factors strongly contribute to the pathogenesis of AF. Recently, single nucleotide polymorphisms (SNPs) in various genes and miRNAs have been reported to be associated with AF. The aim of this review was to discuss the correlation between SNPs in miRNAs and AF, including those miRNAs that are commonly reported as potential biomarkers for AF.

Association of miR-146a, miR-149 and miR-196a2 polymorphisms with neuroblastoma risk in Eastern Chinese population: a three-center case-control study

Neuroblastoma is one of the most common malignancy in childhood, which originates from the developing sympathetic nervous system. Single nucleotide polymorphisms (SNPs) in primary miRNA (pri-miRNA) have shown to associate with cancer susceptibility, including neuroblastoma. Three precursor miRNA (pre-miRNA) SNPs (pre-miR-146a rs2910164, pre-miR-149 rs2292832 and pre-miR-196a2 rs11614913) were found to contribute to pathogenesis of various diseases. Here, to evaluate the association among these three pre-miRNA SNPs and neuroblastoma susceptibility in Eastern Chinese children, we carried out a three-center case-control study involving 312 neuroblastoma cases and 762 healthy controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the association of these three polymorphisms with neuroblastoma risk. However, no significant association was observed among these three SNPs and neuroblastoma susceptibility, in either overall or subgroups analysis by tumor sites, gender and age. Further larger studies consisting of diverse ethnic populations are required to clarify the associations among these three pre-miRNAs polymorphisms and neuroblastoma risk.

Association between miR-499 rs3746444 polymorphism and coronary heart disease susceptibility: An evidence-based meta-analysis of 5063 cases and 4603 controls

MicroRNA-499 (miR-499) rs3746444 polymorphism has been associated with the risk of coronary heart disease (CHD). However, results from several studies are inconsistent. This meta-analysis aimed to further investigate the possible association between miR-499 rs3746444 polymorphism and CHD risk. A total of 9 case-control studies included 5063 CHD cases and 4603 healthy subjects. The A allele at rs374644 was associated with significantly decreased CHD risk in the total population according to the allelic model (OR = 0.80, 95% CI = 0.68-0.93, P = 0.005), homozygous model (OR = 0.52, 95% CI = 0.39-0.71, P < 0.001) and heterozygous model (OR = 0.57, 95% CI = 0.43-0.77, P < 0.001). A similar trend was found specifically in Asian and Chinese populations. In contrast, the wild-type GG genotype at rs374644 was associated with significantly increased CHD risk in the total population, according to the dominant model (OR = 1.83, 95% CI = 1.39-2.42, P < 0.001), and a similar trend was found in Asian and Chinese populations. These results indicate that in the total population, as well as in Asian and Chinese populations, the wild-type GG genotype at rs374644 may be related to increased susceptibility to CHD, while the A allele may be protective against CHD.

Association study of miR-146a, miR-149, miR-196a2, and miR-499 polymorphisms with venous thromboembolism in a Korean population

Despite much progress in microRNA (miRNA) research, information regarding the association between miRNAs and venous thromboembolism (VTE), especially in Asian patients, remains limited. This case-control study sought to determine the correlation between the presence of polymorphisms in the genes encoding the miRNAs miR-146a, miR-149, miR-196a2, miR-499, and VTE in Korean patients. We observed no statistically significant differences in the genotype frequency of miRNA polymorphisms between 300 control individuals and 203 VTE patients. However, we observed a significant association between three allelic combinations of miRNA polymorphisms and VTE risk. Overall, our findings suggest that specific miRNA polymorphisms are associated with the risk of VTE in a Korean population.

miRNA Polymorphisms and Risk of Cardio-Cerebrovascular Diseases: A Systematic Review and Meta-Analysis

Recently extensive focus has been concentrated on the role of miRNAs in the initiation and progression of cardio-cerebrovascular diseases (CCDs) which constitute a range of conditions including cardiovascular diseases (CVDs, especially coronary artery disease (CAD)), congenital heart disease (CHD) and cerebrovascular diseases (CBVDs, especially the ischemic stroke (IS)). An increasing number of studies are evaluating the association between different miRNA polymorphisms and risk of CCDs, but results have been inconclusive. This study represents a comprehensive systematic review and meta-analysis of the association between miRNA polymorphisms and risk of CCDs. PubMed, Embase, Scopus, and Web of Science were queried to identify eligible articles. Odds ratios and 95% confidence intervals were used to assess the association of miRNA polymorphisms with CCD susceptibility. A total of 51 eligible articles evaluating the association of 31 miRNA polymorphisms were identified. Meta-analysis was performed for six miRNA polymorphisms. miR-146a rs2910164 (30 studies: 13,186 cases/14,497 controls), miR-149 rs2292832 (Nine studies: 4116 cases/3511 controls), miR-149 rs71428439 (Three studies: 1556 cases/1567 controls), miR-196a2 rs11614913 (20 studies: 10,144 cases/10,433 controls), miR-218 rs11134527 (Three studies: 2,322 cases/2,754 controls) were not associated with overall CCD. miR-499 rs3746444 was associated with CCD (20 studies: 9564 cases/8876 controls). In the subgroups, rs2910164 and rs3746444 were only associated with CVDs, especially CAD. In conclusion, the results support the existence of a role for miR-146a rs2910164 and miR-499 rs3746444 in determining susceptibility to CCDs, especially CAD.

miR-196a2 (rs11614913) polymorphism is associated with coronary artery disease, but not with in-stent coronary restenosis

OBJECTIVE

The aim of the study was to evaluate the association of miRNA-146a G/C (rs2910164), and miRNA-196a2 C/T (rs11614913) polymorphisms with the presence of coronary artery disease (CAD) and/or restenosis in patients with coronary stent.

MATERIALS AND METHODS

The polymorphisms were determined in 218 patients with CAD who underwent coronary artery stenting (66 with restenosis and 152 without restenosis) and 611 healthy controls using 5' exonuclease TaqMan assays.

RESULTS

The distribution of both polymorphisms was similar in patients with and without restenosis. However, when the whole group of patients (with and without restenosis) was compared to healthy controls, under co-dominant, dominant and additive genetic models, the T allele of the miRNA-196a2 C/T (rs11614913) polymorphism was associated with increased risk of CAD (OR = 2.18, P_co-dom = 0.006, OR = 1.86, P_dom = 0.002, and OR = 1.52, P_add = 0.002, respectively). All models were adjusted for age, type 2 diabetes mellitus, dyslipidemia, hypertension and smoking habit. The "GT" haplotype was associated with increased risk of developing CAD (OR = 1.36, P = 0.046).

CONCLUSIONS

Our data suggests that the T allele of the miRNA-196a2 C/T (rs11614913) polymorphism is associated with the risk of developing CAD, but no association with restenosis was observed.

Increased risk of polycystic ovary syndrome (PCOS) associated with CC genotype of miR-146a gene variation

Polycystic ovary syndrome (PCOS) is an endocrinopathy in reproductive-age women believed to be affected by several genetics and environmental factors or both. Different miRNAs are one of such genetic factors that their associations with PCOS have been implicated. For instance, miR-146a that is well known for strongly regulating the immune response and inflammation was upregulated in serum plasma, follicular fluid and granulosa cells of PCOS patients. Different studies have shown that genetic changes in pre-miRNA can cause change in the expression or biological function of mature miRNA. Therefore, the main aim of this study was to investigate the association of miR-146a gene variation (rs2910164) with the susceptibility to PCOS. This study consists of 180 patients with PCOS and 192 healthy women matched by age and geographical region. Genotyping were determined by using PCR-RFLP in all subjects. The genotype frequency and allele distributions of all subjects were evaluated using Fisher's exact test directed by SPSS v.20. The genotype and allele frequencies of the miR-146a polymorphism (rs2910164) significantly differ between PCOS and healthy controls. The frequencies of CC genotype (p = .054) and 'C' allele (p = .0001) of the miR-146a variant indicated a significant incidence in cases compared to controls. Such association was obtained in co-dominant (OR = 3.16) and dominant (OR = 2.29) models. Result of this study can be proposed that women with miR-146a variation are at a higher risk for developing PCOS, which can be due to up-regulation of miR-146a.

A Meta-Analysis of the Association between Microrna-196A2 and Risk of Ischemic Stroke and Coronary Artery Disease in Asian Population

OBJECT

Single nucleotide polymorphisms (SNPs) of small non-coding RNAs (sncRNAs) that affect the sncRNA function and target gene expression to mediate the risk of certain diseases. The association between the miR-196a2 rs11614913 and ischemic stroke (IS) and coronary artery disease (CAD) is still conflicting and inconclusive. This meta-analysis aimed at analysing studies which have been done so far to get a more precise assessment of the association between the mutation and these two diseases.

METHODS

Electronic databases dated up to April 2018 were searched, retrieved and used. Revman 5.2 software and STATA version 12.0 were used for statistical analysis. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to identify any potential associations. Heterogeneity, publication bias and sensitivity analysis were conducted to measure the robustness of our findings.

RESULTS

The overall meta-analysis results showed that miR-196a2 rs11614913 T > C polymorphism was significantly associated with CAD risk in certain genetic models, as well as in subgroup analysis (CC versus TT, OR = .43, 95%CI = .39-.47, P < .00001). However, no significant association was detected between the miR-196a2 rs11614913 T > C and IS risk in all genetic models.

CONCLUSIONS

Our study suggests that miR-196a2 rs11614913 T > C may contribute to CAD susceptibility but further well-designed studies with larger sample size and comprehensive data are needed to confirm our findings and provide a profound conclusion.

Association Between MicroRNAs Polymorphisms and Risk of Ischemic Stroke: A Meta-Analysis in Chinese Individuals

Objective: Previous studies have demonstrated that some single-nucleotide polymorphisms (SNPs) in miRNAs are related to the risk of ischemic stroke (IS), but the conclusions are still controversial and inconclusive. We performed this meta-analysis to further assess the association between miR-146a C>G (rs2910164), miR-149 T>C (rs2292832), miR-196a2 T>C (rs11614913), miR-499 A>G (rs3746444) and risk of IS in Chinese individuals. Methods: Relevant studies were identified in the databases of PubMed, Embase. The strength of correlation between microRNAs polymorphisms and IS risk was assessed by odds ratios (ORs) and 95% confidence intervals (95% CIs) under five genetic models. Results: 5 studies, containing 2,632 cases and 3,191 controls, were included in this meta-analysis. The overall results of meta-analysis indicated that there were no significant association between miR-146a C>G (rs2910164), miR-149 T>C (rs2292832), miR-196a2 T>C (rs11614913), and the IS risk in the overall analyses. MiR-499 A>G (rs3746444) was associated with an increased IS risk under allele model (OR = 1.30, 95% CI = 1.02-1.66), heterozygous model (OR = 1.35, 95% CI = 1.01-1.79) and dominant model (OR = 1.36, 95% CI = 1.02-1.80) in Chinese. The sensitivity analysis results of these four polymorphisms were similar to the overall results. Conclusion: MiR-499 A>G (rs3746444) G allele and AG, AG + AA genotype might be risk factors of IS in Chinese. No significant association was observed between miR-146a C>G (rs2910164), miR-149 T>C (rs2292832), miR-196a2 T>C (rs11614913), and IS risk. The associations may be different due to geographical factors of China. More explorations in more diverse geographically regions with large sample size are expected to further verify the findings in the future.

Significant association between functional microRNA polymorphisms and coronary heart disease susceptibility: a comprehensive meta-analysis involving 16484 subjects

Molecular epidemiological studies suggest that microRNA polymorphisms may be associated with an increased risk of coronary heart disease (CHD). However, the results of these studies were inconsistent and inconclusive. To derive a more precise evaluation, we performed a meta-analysis focused on the associations between microRNA polymorphisms and CHD risk. PubMed, Embase, CNKI and Wanfang databases were searched. Odds ratios (ORs) with 95% confidence intervals (CIs) were applied to assess the association between microRNA-146a rs2910164, microRNA-196a2 rs11614913, microRNA-499 rs3746444 and microRNA-149 rs71428439 polymorphisms and CHD susceptibility. Heterogeneity, publication bias and sensitivity analysis were conducted to measure the robustness of our findings. A total of thirteen related studies involving 8,120 patients and 8,364 controls were analyzed. Significant associations between microRNA-146a rs2910164 polymorphism and CHD risk were observed in the total population, as well as in subgroup analysis. For microRNA-196a2 rs11614913 and microRNA-499 rs3746444, similarly increased risks were also found. In addition, no significant association was detected between microRNA-149 rs71428439 polymorphism and CHD risk. In conclusion, our meta-analyses suggest that microRNA polymorphisms may be associated with increased risk of CHD development.

Association between a MIR499A polymorphism and diabetic neuropathy in type 2 diabetes

AIMS

Diabetic polyneuropathy (DPN) and cardiovascular autonomic neuropathy (CAN) affect a large percentage of diabetic people and impact severely on quality of life. As it seems that miRNAs and their variations might play a role in these complications, we investigated whether the rs3746444 SNP in the MIR499A gene could be associated with susceptibility to DPN and/or CAN.

METHODS

We analyzed 150 participants with type 2 diabetes. DNA was extracted from peripheral blood samples and genotyping was performed by TaqMan genotyping assay. Cardiovascular tests, MNSI-Q and MDNS for neuropathic symptoms and signs, VPT, and thermal thresholds were used for CAN and DPN assessment. We performed a genotype-phenotype correlation analysis.

RESULTS

We observed that the GG genotype was associated with a higher risk of developing CAN (P=0.002 and OR=16.08, P=0.0005 and OR=35.02, for early and confirmed CAN, respectively) and DPN (P=0.037 and OR=6.56), after correction for BMI, sex, age, HbA1c and disease duration. Moreover, the GG genotype was associated with worse values of MDNS (P=0.017), VPT (P=0.01), thermal thresholds (P=0.01), and CAN score (P<0.001). A logistic multivariate analysis confirmed that MIR499A GG genotype, disease duration and HbA1c contributed to early CAN (R²=0.26), while the same variables and age contributed to DPN (R²=0.21). With a multiple linear regression, we observed that GG genotype (P=0.001) and disease duration (P=0.035) were the main variables contributing to the CAN score (R²=0.35).

CONCLUSIONS

We described for the first time that the MIR499A genetic variation could be involved in diabetic neuropathies susceptibility. In particular, patients carrying the rs3746444 GG genotype had a higher risk of CAN development, together with a more severe form of CAN.

miRNAs as potential therapeutic targets and diagnostic biomarkers for cardiovascular disease with a particular focus on WO2010091204

INTRODUCTION

A number of miRNAs have been reported to be critically involved in the regulation of cardiovascular disease (CVDs). Therefore, the development of potent analogues/inhibitors for miRNAs have thus become a key focus in the present drug discovery. In this review, we discuss the basic research and clinical use of miRNAs as the early diagnosis and therapeutic targets for CVD. We have also focused on the efficiency of therapeutically targeting miR-499, which is considered as one of the most promising molecules for treating CVDs. Areas covered: In this review, we have discussed the patents and patent applications related to miRNAs detected in CVD patients published in recent years. This review also covers the expression pattern of miR-499, as well as it highlights functions of its inhibitors in CVD. We used Google and Pubmed search engines to find relevant patents. Expert opinion: Although a massive number of miRNAs are patented as CVD biomarkers, further work is absolutely required to evaluate the reliable diagnostic values and therapeutic potential of these candidates. Overall, targeting miRNAs is definitely a promising strategy to be investigated for diagnosis and treatment of CVDs in future, however, the delivery system and off-targets effects are still a difficult challenge need to be elucidated.

Associations of microRNA single nucleotide polymorphisms and disease risk and pathophysiology

Single nucleotide polymorphisms (SNPs) are genetic variations that contribute to human phenotypes associated with various diseases. SNPs are involved in the regulation of a broad range of physiological and pathological processes, such as cellular senescence, apoptosis, inflammation, and immune response, by upregulating the expression of classical inflammation markers. Recent studies have suggested that SNPs located in gene-encoding microRNAs (miRNAs) affect various aspects of diseases by regulating the expression or activity of miRNAs. In the last few years, miRNA polymorphisms that increase and/or reduce the risk of developing many diseases, such as cancers, autoimmune diseases, and cardiovascular diseases, have attracted increasing attention not only because of their involvement in the pathophysiology of diseases but also because they can be used as prognostic biomarkers for a variety of diseases. In this review, we summarize the relationships between miRNA SNPs and the pathophysiology and risk of diseases.

A functional variant of miRNA-149 confers risk for allergic rhinitis and comorbid asthma in Chinese children

The prevalence of allergic rhinitis (AR) and asthma has been increasing, and the comorbidity rates of these diseases are very high. Here, 176 AR patients, 124 patients with comorbid AR and asthma (AR-A) and 206 healthy Chinese children as controls were included in a case-control study. Six single-nucleotide polymorphisms (SNPs), miR-146a (rs2910164, rs57095329 and rs6864584), miR-196a2 (rs11614913), miR-499 (rs3746444) and miR-149 (rs2292832), were genotyped. The prevalence of homozygous miR-149 (rs2292832) CC genotype and C allele were considerably increased in AR and AR-A patients, compared with the controls. AR-A group showed higher frequencies of CC genotype and C allele of rs2292832 than AR group. No significant difference in the genotypic and allelic frequencies of other miRNA SNPs was found between the groups. MiR-149 levels in peripheral blood mononuclear cells (PBMCs) were significantly lower in CC (variant type) cases compared with TT (wild-type) cases. In further experiments, PBMCs obtained from the healthy controls with CC, CT and TT genotypes were stimulated by house dust mite extracts, which led to a significant decrease in the levels of miR-149 in PBMCs obtained from CC and TT individuals. This decrease was more pronounced in CC compared with TT cases. Our results demonstrate that miR-149 rs2292832 variant is not only strongly associated with AR and AR-A, but it may lead to an increase in the susceptibility to allergies following the stimulation with an allergen, through the changes in miR149 expression. Additionally, AR patients with CC genotypes were shown to be more susceptible to asthma.