Circulating endothelium-enriched microRNA-126 as a potential biomarker for coronary artery disease in type 2 diabetes mellitus patients

Unraveling the epigenetic fabric of type 2 diabetes mellitus: pathogenic mechanisms and therapeutic implications

Type 2 diabetes mellitus (T2DM) is a rapidly escalating global health concern, with its prevalence projected to increase significantly in the near future. This review delves into the intricate role of epigenetic modifications - including DNA methylation, histone acetylation, and micro-ribonucleic acid (miRNA) expression - in the pathogenesis and progression of T2DM. We critically examine how these epigenetic changes contribute to the onset and exacerbation of T2DM by influencing key pathogenic processes such as obesity, insulin resistance, β-cell dysfunction, cellular senescence, and mitochondrial dysfunction. Furthermore, we explore the involvement of epigenetic dysregulation in T2DM-associated complications, including diabetic retinopathy, atherosclerosis, neuropathy, and cardiomyopathy. This review highlights recent studies that underscore the diagnostic and therapeutic potential of targeting epigenetic modifications in T2DM. We also provide an overview of the impact of lifestyle factors such as exercise and diet on the epigenetic landscape of T2DM, underscoring their relevance in disease management. Our synthesis of the current literature aims to illuminate the complex epigenetic underpinnings of T2DM, offering insights into novel preventative and therapeutic strategies that could revolutionize its management.

Epigenetics of the Pathogenesis and Complications of Type 2 Diabetes Mellitus

Epigenetics of type 2 diabetes mellitus (T2DM) has widened our knowledge of various aspects of the disease. The aim of this review is to summarize the important epigenetic changes implicated in the disease risks, pathogenesis, complications and the evolution of therapeutics in our current understanding of T2DM. Studies published in the past 15 years, from 2007 to 2022, from three primary platforms namely PubMed, Google Scholar and Science Direct were included. Studies were searched using the primary term 'type 2 diabetes and epigenetics' with additional terms such as 'risks', 'pathogenesis', 'complications of diabetes' and 'therapeutics'. Epigenetics plays an important role in the transmission of T2DM from one generation to another. Epigenetic changes are also implicated in the two basic pathogenic components of T2DM, namely insulin resistance and impaired insulin secretion. Hyperglycaemia-i nduced permanent epigenetic modifications of the expression of DNA are responsible for the phenomenon of metabolic memory. Epigenetics influences the development of micro-and macrovascular complications of T2DM. They can also be used as biomarkers in the prediction of these complications. Epigenetics has expanded our understanding of the action of existing drugs such as metformin, and has led to the development of newer targets to prevent vascular complications. Epigenetic changes are involved in almost all aspects of T2DM, from risks, pathogenesis and complications, to the development of newer therapeutic targets.

Emerging role of miRNAs in the regulation of ferroptosis

Ferroptosis is a kind of cell death which has distinctive features differentiating it from autophagy, necrosis and apoptosis. This iron-dependent form of cell death is described by an increase in lipid reactive oxygen species, shrinkage of mitochondria and decrease in mitochondrial cristae. Ferroptosis is involved in the initiation and progression of many diseases and is regarded as a hotspot of investigations on treatment of disorders. Recent studies have shown that microRNAs partake in the regulation of ferroptosis. The impact of microRNAs on this process has been verified in different cancers as well as intervertebral disc degeneration, acute myocardial infarction, vascular disease, intracerebral hemorrhage, preeclampsia, hemorrhagic stroke, atrial fibrillation, pulmonary fibrosis and atherosclerosis. miR-675, miR-93, miR-27a, miR-34a and miR-141 have been shown to affect iron metabolism, antioxidant metabolism and lipid metabolism, thus influencing all pivotal mechanisms in the ferroptosis process. In the current review, we summarize the role of microRNAs in ferroptosis and their involvement in the pathetiology of malignant and non-malignant disorders.

MicroRNAs as Biomarkers for Coronary Artery Disease Related to Type 2 Diabetes Mellitus-From Pathogenesis to Potential Clinical Application

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease with still growing incidence among adults and young people worldwide. Patients with T2DM are more susceptible to developing coronary artery disease (CAD) than non-diabetic individuals. The currently used diagnostic methods do not ensure the detection of CAD at an early stage. Thus, extensive research on non-invasive, blood-based biomarkers is necessary to avoid life-threatening events. MicroRNAs (miRNAs) are small, endogenous, non-coding RNAs that are stable in human body fluids and easily detectable. A number of reports have highlighted that the aberrant expression of miRNAs may impair the diversity of signaling pathways underlying the pathophysiology of atherosclerosis, which is a key player linking T2DM with CAD. The preclinical evidence suggests the atheroprotective and atherogenic influence of miRNAs on every step of T2DM-induced atherogenesis, including endothelial dysfunction, endothelial to mesenchymal transition, macrophage activation, vascular smooth muscle cells proliferation/migration, platelet hyperactivity, and calcification. Among the 122 analyzed miRNAs, 14 top miRNAs appear to be the most consistently dysregulated in T2DM and CAD, whereas 10 miRNAs are altered in T2DM, CAD, and T2DM-CAD patients. This up-to-date overview aims to discuss the role of miRNAs in the development of diabetic CAD, emphasizing their potential clinical usefulness as novel, non-invasive biomarkers and therapeutic targets for T2DM individuals with a predisposition to undergo CAD.

MicroRNAs as biomarkers for monitoring cardiovascular changes in Type II Diabetes Mellitus (T2DM) and exercise

Introduction

MicroRNAs (miRNAs) have been shown to be altered in both CVD and T2DM and can have an application as diagnostic and prognostic biomarkers. miRNAs are released into circulation when the cardiomyocyte is subjected to injury and damage.

Objectives

Measuring circulating miRNA levels in human plasma may be of great potential use for measuring the extent of damage to cardiomyocytes and response to exercise. This review is aimed to highlight the potential application of miRNAs as biomarkers of CVD progression in T2DM, and the impact of exercise on recovery.

Methods

The review aims to examine whether the health improvements following exercise in T2DM patients are reflective of changes in expression of plasma miRNAs. For this purpose, studies were identified from the literature that have established a correlation between diabetes, disease progression and plasma miRNA levels. We also reviewed studies which looked at the effect of exercise on plasma miRNA levels.

Results

The review identified miRNA signatures that are affected by T2DM and DHD and a subset of these miRNAs that are also affected by different types of exercise. This approach helped us to identify those miRNAs whose expression and function can be altered by regular bouts of exercise.

Conclusions

miRNAs identified as part of this review can serve as tools to monitor the cardio-protective, anti-inflammatory and metabolic effects of exercise in people suffering from T2DM. Future research should focus on regulation of these miRNAs in T2DM and how they can be altered by appropriate exercise interventions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-022-01066-4.

Circulating miRNA as potential biomarkers for diabetes mellitus type 2: should we focus on searching for sex differences?

microRNAs are non-coding molecules, approximately 22 nucleotides in length, that regulate various cellular processes. A growing body of evidence has suggested that their dysregulated expression is involved in the pathogenesis of diverse diseases, including diabetes mellitus type 2 (DM2). Early onset of this chronic and complex metabolic disorder is frequently undiagnosed, leading to the development of severe diabetic complications. Notably, DM2 prevalence is rising globally and an increasing number of articles demonstrate that DM2 susceptibility, development, and progression differ between males and females. Therefore, this paper discusses the role of microRNAs as a source of novel diagnostic biomarkers for DM2 and aims to underline the importance of sex disparity in biomarkers research. Taking into account an urgent need for the development of sex-specific diagnostic strategies in DM2, recent results have shown that circulating miRNAs are promising candidates for sex-biased biomarkers.

Circulating Nucleic Acid-Based Biomarkers of Type 2 Diabetes

Type 2 diabetes (T2D) is a deficiency in how the body regulates glucose. Uncontrolled T2D will result in chronic high blood sugar levels, eventually resulting in T2D complications. These complications, such as kidney, eye, and nerve damage, are even harder to treat. Identifying individuals at high risk of developing T2D and its complications is essential for early prevention and treatment. Numerous studies have been done to identify biomarkers for T2D diagnosis and prognosis. This review focuses on recent T2D biomarker studies based on circulating nucleic acids using different omics technologies: genomics, transcriptomics, and epigenomics. Omics studies have profiled biomarker candidates from blood, urine, and other non-invasive samples. Despite methodological differences, several candidate biomarkers were reported for the risk and diagnosis of T2D, the prognosis of T2D complications, and pharmacodynamics of T2D treatments. Future studies should be done to validate the findings in larger samples and blood-based biomarkers in non-invasive samples to support the realization of precision medicine for T2D.

Salivary microRNA-126 and 135a: a potentially non-invasive diagnostic biomarkers of type- 2 diabetes

Purpose

Emerging of miRNAs have illustrated the new mechanistic layer to regulate type 2 diabetes process and suggests a possible role of these RNAs in this defect. Thus, we designed this study to improve our understanding of salivary miRNA-126 and 135a expression utility as an easy of collection and non-invasive way in diabetic patients instead of blood sample.

Methods

This case-control study was done on T₂D (n = 40) and healthy individuals (n = 40). The level of biochemical parameters were determined by enzymatic methods as well as glycosylated hemoglobin (HbA1c) was measured by immunoturbidimetry. We used the pooled whole stimulated saliva sample from cases and controls to assess the differentiation expression of miRNA 126 and 135-a with quantitative RT-PCR method. Unpaired Student's t test, Pearson's correlation coefficient and Receiver Operating Characteristic (ROC) analysis were used.

Results

A correlation was observed between the level of HbA1c, glucose and lipid profiles (TG, TC, and LDL) in serum and whole stimulated saliva samples in T₂D patients compared to control (p < 0.001). miR-135a expression was considerably higher by 4.7-fold in T₂D compared to the control group (1.8-fold) (p < 0.001) while the miR126 expression was significantly decreased by 3.9-fold in T₂D compared to the controls (6.3-fold) (p < 0.001).

Conclusions

The results of this case and control study showed that miR-135a and miR126 expression in saliva fluid as a reliable biomarkers and non-invasive approach in combination by change of lipid profiles, glucose and HbA1c may be used to monitor diabetic and non-diabetic patients, while further research is needed to investigate the relationship of these salivary miRNAs (miR135a, miR126) levels change on shifting the levels of clinical laboratory outcomes.

LncRNAs: Novel Biomarkers for Pancreatic Cancer

Pancreatic cancer is one of the most deadly neoplasms and the seventh major cause of cancer-related deaths among both males and females. This cancer has a poor prognosis due to the lack of appropriate methods for early detection of cancer. Long non-coding RNAs (lncRNAs) have been recently found to influence the progression and initiation of pancreatic cancer. MACC1-AS1, LINC00976, LINC00462, LINC01559, HOXA-AS2, LINC00152, TP73-AS1, XIST, SNHG12, LUCAT1, and UCA1 are among the oncogenic lncRNAs in pancreatic cancer. On the other hand, LINC01111, LINC01963, DGCR5, MEG3, GAS5, and LINC00261 are among tumor suppressor lncRNAs in this tissue. In the current review, we summarize the roles of these two classes of lncRNAs in pancreatic cancer and discuss their potential as attractive diagnostic and prognostic biomarkers for pancreatic cancer. We also identified that the low expression of MEG3, LINC01963, and LINC00261 and the high expression of MACC1-AS1, LINC00462, LINC01559, and UCA1 were significantly correlated with worse survival in pancreatic cancer patients. Further research on these lncRNAs will provide new clues that could potentially improve the early diagnosis, prognostic prediction, and personalized treatments of patients with pancreatic cancer.

Novel Cardiovascular Risk Factors in Patients with Diabetic Kidney Disease

Patients with diabetic kidney disease (DKD) are at very high risk for cardiovascular events. Only part of this increased risk can be attributed to the presence of diabetes mellitus (DM) and to other DM-related comorbidities, including hypertension and obesity. The identification of novel risk factors that underpin the association between DKD and cardiovascular disease (CVD) is essential for risk stratification, for individualization of treatment and for identification of novel treatment targets.In the present review, we summarize the current knowledge regarding the role of emerging cardiovascular risk markers in patients with DKD. Among these biomarkers, fibroblast growth factor-23 and copeptin were studied more extensively and consistently predicted cardiovascular events in this population. Therefore, it might be useful to incorporate them in risk stratification strategies in patients with DKD to identify those who would possibly benefit from more aggressive management of cardiovascular risk factors.

miRNAs as biomarkers for diagnosis of type 2 diabetes: A systematic review

BACKGROUND

This systematic review summarizes results of studies that evaluated the expression of microRNAs (miRs) in prediabetes or type 2 diabetes (T2D).

METHODS

The information was obtained from PubMed, EMBL-EBI, Wanfang, Trip Database, Lilacs, CINAHL, Human microRNA Disease Database (HMDD) v3.0, and Google. A qualitative synthesis of the results was performed and miRs frequency was graphically represented. From 1893 identified studies, only 55 fulfilled the inclusion criteria. These 55 studies analyzed miRs in T2D, and of them, 13 also described data of prediabetes.

RESULTS

In diabetics, 122 miRs were reported and 35 miRs for prediabetics. However, we identified that five miRs (-122-5p, 144-3p, 210, 375, and -126b) were reported more often in diabetics and four (144-3p, -192, 29a, and -30d) in prediabetics.

CONCLUSIONS

Circulating miRs could be used as biomarkers of T2D. However, it is necessary to validate these microRNAs in prospective and multicenter studies with different population subgroups, considering age, gender, and risk factors.

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.

Epigenetics, microRNA and Metabolic Syndrome: A Comprehensive Review

Epigenetics refers to the DNA chemistry changes that result in the modification of gene transcription and translation independently of the underlying DNA coding sequence. Epigenetic modifications are reported to involve various molecular mechanisms, including classical epigenetic changes affecting DNA methylation and histone modifications and small RNA-mediated processes, particularly that of microRNAs. Epigenetic changes are reversible and are closely interconnected. They are recognised to play a critical role as mediators of gene regulation, and any alteration in these mechanisms has been identified to mediate various pathophysiological conditions. Moreover, genetic predisposition and environmental factors, including dietary alterations, lifestyle or metabolic status, are identified to interact with the human epigenome, highlighting the importance of epigenetic factors as underlying processes in the aetiology of various diseases such as MetS. This review will reflect on how both the classical and microRNA-regulated epigenetic changes are associated with the pathophysiology of metabolic syndrome. We will then focus on the various aspects of epigenetic-based strategies used to modify MetS outcomes, including epigenetic diet, epigenetic drugs, epigenome editing tools and miRNA-based therapies.

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.

Circulating microRNAs associated with prediabetes and geographic location in Latinos

Background

Globally, type 2 diabetes is highly prevalent in individuals of Latino ancestry. The reasons underlying this high prevalence are not well understood, but both genetic and lifestyle factors are contributors. Circulating microRNAs are readily detectable in blood and are promising biomarkers to characterize biological responses (i.e., changes in gene expression) to lifestyle factors. Prior studies identified relationships between circulating microRNAs and risk for type 2 diabetes, but Latinos have largely been under-represented in these study samples.

Aims/hypothesis

The aim of this study was to assess for differences in expression levels of three candidate microRNAs (miR-126, miR-146, miR-15) between individuals who had prediabetes compared to normal glycemic status and between individuals who self-identified with Latino ancestry in the United States (US) and native Mexicans living in or near Leon, Mexico.

Methods

This was a cross-sectional study that included 45 Mexicans and 21 Latino participants from the US. Prediabetes was defined as fasting glucose 100–125 mg/dL or 2-h post-glucose challenge between 140 and 199 mg/dL. Expression levels of microRNAs from plasma were measured by qPCR. Linear and logistic regression models were used to assess relationships between individual microRNAs and glycemic status or geographic site.

Results

None of the three microRNAs was associated with risk for type 2 diabetes. MiR-146a and miR-15 were significantly lower in the study sample from Mexico compared to the US. There was a significant interaction between miR-146a and BMI associated with fasting blood glucose.

Conclusions/interpretation

This study did not replicate in Latinos prior observations from other racial groups of associations between miR-126, miR-146a, and miR-15 and risk for type 2 diabetes. Future studies should consider other microRNAs related to different biological pathways as possible biomarkers for type 2 diabetes in Latinos.

Research Status of Differentially Expressed Noncoding RNAs in Type 2 Diabetes Patients

AIMS

Noncoding RNAs (ncRNAs) play an important role in the occurrence and development of type 2 diabetes mellitus (T2DM). This paper summarized the current evidences of the involvement microRNAs, long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs) in the differential expressions and their interaction with each other in T2DM.

METHODS

The differentially expressed miRNAs, lncRNAs, and circRNAs in the blood circulation (plasma, serum, whole blood, and peripheral blood mononuclear cells) of patients with T2DM were found in PubMed, GCBI, and other databases. The interactions between ncRNAs were predicted based on the MiRWalk and the DIANA Tools databases. The indirect and direct target genes of lncRNAs and circRNAs were predicted based on the starBase V2.0, DIANA Tools, and LncRNA-Target databases. Then, GO and KEGG analysis on all miRNA, lncRNA, and circRNA target genes was performed using the mirPath and Cluster Profile software package in R language. The lncRNA-miRNA and circRNA-miRNA interaction diagram was constructed with Cytoscape. The aim of this investigation was to construct a mechanism diagram of lncRNA involved in the regulation of target genes on insulin signaling pathways and AGE-RAGE signaling pathways of diabetic complications.

RESULTS

A total of 317 RNAs, 283 miRNAs, and 20 lncRNAs and circRNAs were found in the circulation of T2DM. Dysregulated microRNAs and lncRNAs were found to be involved in signals related to metabolic disturbances, insulin signaling, and AGE-RAGE signaling in T2DM. In addition, lncRNAs participate in the regulation of key genes in the insulin signaling and AGE-RAGE signaling pathways through microRNAs, which leads to insulin resistance and diabetic vascular complications.

CONCLUSION

Noncoding RNAs participate in the occurrence and development of type 2 diabetes and lead to its vascular complications by regulating different signaling pathways.

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.

Exercise Regulates MicroRNAs to Preserve Coronary and Cardiac Function in the Diabetic Heart

RATIONALE

Diabetic heart disease (DHD) is a debilitating manifestation of type 2 diabetes mellitus. Exercise has been proposed as a potential therapy for DHD, although the effectiveness of exercise in preventing or reversing the progression of DHD remains controversial. Cardiac function is critically dependent on the preservation of coronary vascular function.

OBJECTIVE

We aimed to elucidate the effectiveness and mechanisms by which exercise facilitates coronary and cardiac-protection during the onset and progression of DHD.

METHODS AND RESULTS

Diabetic db/db and nondiabetic mice, with or without underlying cardiac dysfunction (16 and 8 weeks old, respectively) were subjected to either moderate-intensity exercise or high-intensity exercise for 8 weeks. Subsequently, synchrotron microangiography, immunohistochemistry, Western blot, and real-time polymerase chain reaction were used to assess time-dependent changes in cardiac and coronary structure and function associated with diabetes mellitus and exercise and determine whether these changes reflect the observed changes in cardiac-enriched and vascular-enriched microRNAs (miRNAs). We show that, if exercise is initiated from 8 weeks of age, both moderate-intensity exercise and high-intensity exercise prevented the onset of coronary and cardiac dysfunction, apoptosis, fibrosis, microvascular rarefaction, and disruption of miRNA signaling, as seen in the nonexercised diabetic mice. Conversely, the cardiovascular benefits of moderate-intensity exercise were absent if the exercise was initiated after the diabetic mice had already established cardiac dysfunction (ie, from 16 weeks of age). The experimental silencing or upregulation of miRNA-126 activity suggests the mechanism underpinning the cardiovascular benefits of exercise were mediated, at least in part, through tissue-specific miRNAs.

CONCLUSIONS

Our findings provide the first experimental evidence for the critical importance of early exercise intervention in ameliorating the onset and progression of DHD. Our results also suggest that the beneficial effects of exercise are mediated through the normalization of cardiovascular-enriched miRNAs, which are dysregulated in DHD.

Circulating microRNA expression profiling and bioinformatics analysis of patients with coronary artery disease by RNA sequencing

BACKGROUND

MicroRNAs play a vital role in coronary artery disease. Abnormal expression of microRNAs has been found to be associated with the occurrence of CAD.

METHODS

We identified significantly differentially expressed microRNAs in plasma between 40 patients with CAD and 10 controls with NCA using RNA sequencing. The differentially expressed microRNAs were analyzed for Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment.

RESULTS

Fifty cDNA libraries were constructed and sequenced, and a total of 1871.82 M raw reads were obtained, and 2135 microRNAs were found. Compared to the expressed microRNAs of NCA controls, 159 microRNAs were differentially expressed in CAD patients, including 119 upregulated microRNAs and 40 downregulated microRNAs. The top 10 upregulated miRNAs were miR-144-3p, miR-34a-5p, miR-15b-3p, miR-22-3p, miR-29b-3p, miR-1270, miR-6891-5p, miR-106a-5p, miR-15b-5p, and hsa-miR-499b-3p. The top ten downregulated miRNAs were miR-4437, miR-6842-3p, miR-4664-3p, miR-671-3p, miR-219a-1-3p, miR-7848-3p, miR-664a-3p, miR-1284, miR-361-3p, and miR-6780a-5p. The target genes of differentially expressed microRNAs were related to many basic biological terms, such as biological process, cellular component, and molecular function. According to the KEGG pathway analysis, the most enriched pathways of the differentially expressed microRNAs were endocytosis, focal adhesion, axon guidance, and so on. Furthermore, six upregulated and two downregulated microRNAs were detected by qRT-PCR (Quantitative Real-time PCR) and ROC analysis for diagnosing CAD.

CONCLUSION

The results suggest that the expression levels of some microRNAs may play a vital role in the physiological and pathological course of CAD. Our study may provide useful information for the diagnosis and treatment of CAD.

Dysregulation of MicroRNA Regulatory Network in Lower Extremities Arterial Disease

Atherosclerosis and its comorbidities are the major contributors to the global burden of death worldwide. Lower extremities arterial disease (LEAD) is a common manifestation of atherosclerotic disease of arteries of lower extremities. MicroRNAs belong to epigenetic factors that regulate gene expression and have not yet been extensively studied in LEAD. We aimed to indicate the most promising microRNA and gene expression signatures of LEAD, to identify interactions between microRNA and genes and to describe potential effect of modulated gene expression. High-throughput sequencing was employed to examine microRNAome and transcriptome of peripheral blood mononuclear cells of patients with LEAD, in relation to controls. Statistical significance of microRNAs and genes analysis results was evaluated using DESeq2 and uninformative variable elimination by partial least squares methods. Altered expression of 26 microRNAs (hsa-let-7f-1-3p, hsa-miR-34a-5p, -122-5p, -3591-3p, -34a-3p, -1261, -21-5p, -15a-5p, -548d-5p, -34b-5p, -424-3p, -548aa, -548t-3p, -4423-3p, -196a-5p, -330-3p, -766-3p, -30e-3p, -125b-5p, -1301-3p, -3184-5p, -423-3p, -339-3p, -138-5p, -99a-3p, and -6087) and 14 genes (AK5, CD248, CDS2, FAM129A, FBLN2, GGT1, NOG, NRCAM, PDE7A, RP11-545E17.3, SLC12A2, SLC16A10, SLC4A10, and ZSCAN18) were the most significantly differentially expressed in LEAD group compared to controls. Discriminative value of revealed microRNAs and genes were confirmed by receiver operating characteristic analysis. Dysregulations of 26 microRNAs and 14 genes were used to propose novel biomarkers of LEAD. Regulatory interactions between biomarker microRNAs and genes were studied in silico using R multiMiR package. Functional analysis of genes modulated by proposed biomarker microRNAs was performed using DAVID 6.8 tools and revealed terms closely related to atherosclerosis and, interestingly, the processes involving nervous system. The study provides new insight into microRNA-dependent regulatory mechanisms involved in pathology of LEAD. Proposed microRNA and gene biomarkers of LEAD may provide new diagnostic and therapeutic opportunities.

Upregulation of Circulating Cardiomyocyte-Enriched miR-1 and miR-133 Associate with the Risk of Coronary Artery Disease in Type 2 Diabetes Patients and Serve as Potential Biomarkers

Circulating miRNAs are increasingly suggested as clinical biomarker for diseases. We evaluated the expression of circulating cardiomyocyte-enriched miR-1 and miR-133 by real-time PCR in blood from patients with type 2 diabetes (T2D) without and with coronary artery disease (CAD) and healthy controls, investigated their association with the risk of CAD risk and their potential as biomarkers. The two miRNAs were upregulated in patients with T2D and CAD compared with controls, associated with CAD risk and remained significant after adjustment for multiple confounders. LDL-C was a positive predictor for miR-1 and miR-133, and mean blood pressure was also a positive predictor for miR-133. Both miRNAs strongly distinguished CAD from controls. miR-1 significantly distinguished CAD from T2D with higher diagnostic ability than miR-133, whereas the miR-1/miR-133 combination improved the diagnostic value. Upregulation of circulating miR-1 and miR-133 associate with the risk of CAD in T2D patients and may serve as diagnostic biomarkers.

Deciphering Non-coding RNAs in Cardiovascular Health and Disease

After being long considered as “junk” in the human genome, non-coding RNAs (ncRNAs) currently represent one of the newest frontiers in cardiovascular disease (CVD) since they have emerged in recent years as potential therapeutic targets. Different types of ncRNAs exist, including small ncRNAs that have fewer than 200 nucleotides, which are mostly known as microRNAs (miRNAs), and long ncRNAs that have more than 200 nucleotides. Recent discoveries on the role of ncRNAs in epigenetic and transcriptional regulation, atherosclerosis, myocardial ischemia/reperfusion (I/R) injury and infarction (MI), adverse cardiac remodeling and hypertrophy, insulin resistance, and diabetic cardiomyopathy prompted vast interest in exploring candidate ncRNAs for utilization as potential therapeutic targets and/or diagnostic/prognostic biomarkers in CVDs. This review will discuss our current knowledge concerning the roles of different types of ncRNAs in cardiovascular health and disease and provide some insight on the cardioprotective signaling pathways elicited by the non-coding genome. We will highlight important basic and clinical breakthroughs that support employing ncRNAs for treatment or early diagnosis of a variety of CVDs, and also depict the most relevant limitations that challenge this novel therapeutic approach.

Blood-based microRNAs as diagnostic biomarkers to discriminate localized prostate cancer from benign prostatic hyperplasia and allow cancer-risk stratification

Prostate cancer (PCa) is the second most diagnosed malignancy, and the leading cause of cancer-associated mortality among males. Prostate-specific antigen (PSA) has long been used for the detection of PCa. However, PSA levels increase in PCa and benign prostatic hyperplasia (BPH), and are associated with a poor disease outcome. Circulating microRNAs (miRNAs) have been determined to be highly stable in the circulation, and could be utilized as biomarkers to improve disease diagnosis and management. In the present study, the effectiveness of four PCa-associated miRNAs in the discrimination of PCa from BPH and the risk-stratification of PCa was assessed. The study included 100 participants: 35 patients with localized PCa, 35 patients with BPH and 30 healthy subjects. Patients with PCa were categorized based on their tumor stage (T), PSA level and Gleason score (GS) into low-(T 1/2, PSA <10 ng/ml or GS ≤7) and high-risk groups (T 3/4, PSA >20 ng/ml or GS ≥8). Reverse transcription-quantitative polymerase chain reaction was employed to assess the miRNA expression in peripheral blood samples. Significantly reduced expression of miR-15a, miR-126, miR-192 and miR-377 was observed in patients with PCa compared with patients with BPH and healthy subjects. In addition, the expression of the four miRNAs was lower in high-risk PCa patients than in low-risk PCa patients, with miR-126 being the most downregulated. The expression of the four miRNAs was also significantly and independently associated with PCa. Receiver operating characteristic curve analysis revealed a significant ability of the miRNAs to distinguish patients with PCa from those with BPH, patients with PCa from controls and low-risk PCa from high-risk PCa. These data suggested that expression of these miRNAs in the blood circulation may be promising, non-invasive biomarkers for the early detection of localized PCa, and for PCa risk stratification. Further validations of the clinical implementation of these results are warranted in a larger cohort.

Expression of microRNA‑377 and microRNA‑192 and their potential as blood‑based biomarkers for early detection of type 2 diabetic nephropathy

The increased incidence of diabetic nephropathy (DN) in type 2 diabetes (T2D) requires novel markers for the early detection of DN. Previously, microRNAs (miRs) have been demonstrated to be promising disease biomarkers. The present study evaluated the biomarker potential of DN‑associated miR‑377 and miR‑192 in the early stages of DN. The study included 85 participants: 55 patients with T2D (30 without DN and 25 with DN) and 30 healthy controls. The patients with T2D were classified according to albumin‑to‑creatinine ratio and were split into three groups: Normoalbuminuric group (n=30), microalbuminuric group (n=15) and macroalbuminuric group (n=10). Reverse transcription‑quantitative polymerase chain reaction analysis was used to evaluate blood miR expression. It was observed that there was higher miR‑377 expression and lower miR‑192 expression in T2D patients with and without DN compared with healthy controls (P<0.05). miR‑377 was higher in the normoalbuminuric group and gradually increased in the microalbuminuric and macroalbuminuric groups (P<0.05), whereas miR‑192 was lower in the macroalbuminuric group compared with the normoalbuminuric group (P<0.05). Regression analysis revealed direct associations between the two miRs and albuminuria (P<0.05). miR‑377 was independently associated with DN risk, even following multivariable adjustment, and albuminuria was the only predictor of miR‑377 (P<0.001). In discriminating overall patients from healthy subjects, ROC analysis revealed areas under the curve (AUCs) of 0.851 for miR377 and 0.774 for miR‑192 (P<0.001). In discriminating the normoalbuminuric group from the microalbuminuric/macroalbuminuric groups, the AUCs were 0.711 (P=0.008) and 0.70 (P=0.049) for miR‑377 and miR‑192, respectively. In patients with microalbuminuria and macroalbuminuria, miR‑377 correlated positively with albuminuria and negatively with renal function, whereas miR‑192 correlated negatively with albuminuria and positively with renal function (P=0.001), and the two miRs were correlated with known risk factors of DN (P<0.05). The results suggested that blood‑based miR‑377 and miR‑192 may serve as potential biomarkers for early detection of DN. Further validation studies are required with larger sample sizes.

miR-181c-3p and -5p promotes high-glucose-induced dysfunction in human umbilical vein endothelial cells by regulating leukemia inhibitory factor

Diabetes mellitus is a chronic metabolic disease with high blood glucose level and closely related to endothelial dysfunction, an important factor in the pathogenesis of vascular changes. Several miRNAs have been reported to be altered in a diabetic environment including miR-181c. In the article, we found that the expression of miR-181c-3p and miR-181c-5p was significantly downregulated under glucose treatment in a dose-dependent manner and in peripheral blood from diabetic patients compared with healthy participants. We explored the role of miR-181c-3p and miR-181c-5p in high glucose (HG)-induced dysfunction in human umbilical vein endothelial cells (HUVECs) by regulating leukemia inhibitory factor (LIF), their potential target with binding sites in 3-UTR region, that is also closely related to glucose metabolism. In addition, miR-181c-3p and miR-181c-5p significantly enhanced HG-induced oxidative stress injury by increasing malondialdehyde (MDA) and reactive oxygen species (ROS) production and promoted HG-induced HUVECs apoptosis, confirmed by TUNEL staining. LIF partially reduced those effects by decreasing oxidative stress and inhibiting cell apoptosis. Therefore, knocking down of LIF in HUVECs by LIF siRNA transfection, significantly increased HG-induced MDA and ROS production and induced more intense HUVECs apoptosis. Our results indicate that miR-181c-3p and miR-181c-5p promote HG-induced HUVECs injury through their target LIF.

Potential value of circulating microRNA-126 and microRNA-210 as biomarkers for type 2 diabetes with coronary artery disease

BACKGROUND

Macrovascular complications are the main cause of morbidity and mortality among the diabetic patients. MicroRNAs (miRNAs), a family of small non-coding RNAs, play vital roles in the regulation of blood glucose level and the concurrent cardiovascular complications of type 2 diabetes. We hypothesized that plasma miR-126 and miR-210 are linked to coronary artery disease (CAD) in these diabetes patients.

METHODS

Fasting blood samples were collected from 20 healthy volunteers and 100 patients with diabetes (54 patients without CAD and 46 patients with CAD). Plasma miR-126 and miR-210 expressions were assessed by quantitative real time PCR. Specificity and sensitivity of miR-126 and miR-210 to discriminate CAD with diabetes was determined by receiver operating characteristic curve analysis. Correlations between miR-126 and miR-210 and studied characteristics in diabetes patients with and without CAD were compared.

RESULTS

Plasma relative expressions of miR-126 and miR-210 were 0.38 ± 0.03 and 5.3 ± 0.56 in diabetes alone vs. 0.08 ± 0.03 and 21.44 ± 0.97 in diabetes with CAD, respectively (both p < 0.0001). Levels of miR-126 and miR-210 significantly correlated with certain glycemic and lipid indices. The miRNAs significantly discriminated between diabetes with and without CAD at cut-off values of 0.055 (sensitivity 91.3%, specificity 100%) for miR-126 and of 17.59 (sensitivity 93.5%, specificity 100%) for miR-210.

CONCLUSION

Plasma miR-126 and miR-210 levels may be biomarkers for diabetes with or without CAD.

Evaluation of Two-Diabetes Related microRNAs Suitability as Earlier Blood Biomarkers for Detecting Prediabetes and type 2 Diabetes Mellitus

Increased the incidence of prediabetes and type 2 diabetes (T2D) worldwide raises an urgent need to develop effective tools for early disease detection to facilitate future preventive interventions and improve patient’s care. We evaluated the suitability of diabetes-related miR-375 and miR-9 as earlier biomarkers for detecting prediabetes and T2D.TaqMan-based RT-qPCR was used to quantify the expression of miRNAs in peripheral blood of 30 prediabetes patients, 30 T2D patients and 30 non-diabetic healthy controls. Compared to controls, miR-375 and miR-9 were expressed at higher levels in prediabetes patients and progressively more enriched in T2D patients. Both miRNAs were directly associated with the presence of prediabetes and T2D independently of known risk factors to T2D and miR-375 was independently associated with the development of T2D. Both miRNAs were positively correlated with the glycemic status and other T2D risk factors. The ROC analysis indicated good diagnostic abilities for miR-375 to distinguish overall patients from control and prediabetes from T2D patients. Whereas, miR-9 showed lower values and borderline significance in discriminating the subject groups. The combination of miRNAs enhanced the predictability to discriminate patients from control. These results suggest that miR-375 and miR-9 are associated with the susceptibility to developing T2D and miR-375 alone or in combination with miR-9 could serve as biomarkers for early detection of prediabetes and T2D.

MicroRNAs in the pathogenesis of type 2 diabetes: new research progress and future direction

miRNA is a short non-coding RNA that can influence mRNA processing at the post-transcriptional level. A large number of miRNAs have been found in virtually all species so far, and these small molecules play an important role in many different physiological processes and various pathologic conditions, such as cell metabolism, cancer, autoimmune disease, and diabetes mellitus. T2D arises from a dysregulated response to the elevated glucose level in the circulation. The prevalence of T2D has increased dramatically in all age groups, and T2D in older adults is associated with more T2D complications and higher mortality. Despite the existing findings describing the pathological mechanism, T2D pathology is more complex and the pathophysiology of the disease is still not fully elucidated. In this review, we summarize the current understanding of miRNA-mediated modulation of gene expression in T2D pathogenesis, as well as related signaling pathways, and insight into the important role of miRNA in various T2D complications. Furthermore, the potential therapeutic value of miRNA for T2D patients is also discussed in detail.

Regulatory RNAs and cardiovascular disease - with a special focus on circulating microRNAs

MicroRNAs (miRNAs) are a class of short non-coding regulatory RNA molecules which play an important role in intracellular communication and cell signaling and which influence cellular processes such as proliferation, differentiation, and cellular death. Over the past two decades, the crucial role of microRNAs in controlling tissue homeostasis and disease in cardiovascular systems has become widely recognized. By controlling the expression levels of their targets, several miRNAs have been shown to modulate the function of endothelial cells (miR-221/222 and -126), vascular smooth muscle cells (miR-143/145) and macrophages (miR-33, -758, and -26), thereby regulating the development and progression of atherosclerosis. The stability of miRNAs within the blood suggests that circulating miRNAs may function as important biomarkers of disease development and progression. Numerous circulating miRNAs have been found to be dysregulated in a wide variety of different disease states, including diabetes, cancer, and cardiovascular disease.

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.

microRNA in Cardiovascular Aging and Age-Related Cardiovascular Diseases

Over the last decades, life expectancy has significantly increased although several chronic diseases persist in the population, with aging as the leading risk factor. Despite improvements in diagnosis and treatment, many elderlies suffer from cardiovascular problems that are much more frequent in an older, more fragile organism. In the long term, age-related cardiovascular diseases (CVDs) contribute to the decline of quality of life and ability to perform normal activities of daily living. microRNAs (miRNAs) are a class of small non-coding RNAs that regulate gene expression at the posttranscriptional level in both physiological and pathological conditions. In this review, we will focus on the role of miRNAs in aging and age-related CVDs as heart failure, hypertension, atherosclerosis, atrial fibrillation, and diabetes mellitus. miRNAs are key regulators of complex biological mechanisms, representing an exciting potential therapeutic target in CVDs. Moreover, one major challenge in geriatric medicine is to find reliable biomarkers for diagnosis, prognosis, and prediction of the response to specific drugs. miRNAs represent a very promising tool due to their stability in the circulation and unique signature in CVDs. However, further studies are needed to investigate their translational potential in the real clinical practice.

Circulating microRNAs and diabetes mellitus: a novel tool for disease prediction, diagnosis, and staging?

Diabetes is a complex, multifactorial group of metabolic diseases characterized by chronic hyperglycaemia due to pancreatic beta-cell dysfunction and/or loss. It is characterized by an asymptomatic and highly variable prodromic phase, which renders diabetes mellitus difficult to be predicted with sufficient accuracy. Despite several efforts in the identification and standardization of newly trustable. Biomarkers able to predict and follow-up diabetes and to specifically subtype its different forms, few of them have proven of clinical utility. Recently, a new class of endogenous non-coding small RNAs, namely microRNAs, have been indicated as putative biomarkers, being released by cells and tissues and found in a cell-free circulating form in many biological fluids, including serum and/or plasma. MicroRNAs have been initially identified as promising biomarkers in cancer, and nowadays their application has been extended to other diseases, including diabetes. Although an increasing number of studies focused on the evaluation of circulating microRNAs in diabetes, few reproducibly identified microRNAs as biomarkers for disease prediction or follow-up. Technological problems as well as the need to obtain highly standardized operating procedures and methods are still an issue in such research field. In this review, we comprehensively resume the main and most recent findings on circulating microRNAs, and their possible use as biomarkers to predict and follow-up diabetes and its complications, as well as the methodological challenges to standardize accurate operating procedures for their analysis.

MicroRNAs and Cardiovascular Disease in Diabetes Mellitus

Cardiovascular disease (CVD) is the major macrovascular complication of diabetes mellitus. Recently, although CVD morbidity and mortality have decreased as a result of comprehensive control of CVD risk factors, CVD remains the leading cause of death of patients with diabetes in many countries, indicating the potential underlying pathophysiological mechanisms. MicroRNAs are a class of noncoding, single-stranded RNA molecules that are involved in β-cell function, insulin secretion, insulin resistance, skeletal muscle, and adipose tissue and which play an important role in glucose homeostasis and the pathogenesis of diabetic complications. Here, we review recent progress in research on microRNAs in endothelial cell and vascular smooth muscle cell dysfunction, macrophage and platelet activation, lipid metabolism abnormality, and cardiomyocyte repolarization in diabetes mellitus. We also review the progress of microRNAs as potential biomarkers and therapeutic targets of CVD in patients with diabetes.

Recent advances in molecular biomarkers for diabetes mellitus: a systematic review

CONTEXT

Diabetes is a growing global metabolic epidemic. Current research is focussing on exploring how the biological processes and clinical outcomes of diabetes are related and developing novel biomarkers to measure these relationships, as this can subsequently improve diagnostic, therapeutic and management capacity.

OBJECTIVE

The objective of this study is to identify the most recent advances in molecular biomarkers of diabetes and directions that warrant further research.

METHODS

Using a systematic search strategy, the MEDLINE, CINAHL and OVID MEDLINE databases were canvassed for articles that investigated molecular biomarkers for diabetes. Initial selections were made based on article title, whilst final inclusion was informed by a critical appraisal of the full text of each article.

RESULTS

The systematic search returned 246 records, of which 113 were unique. Following screening, 29 records were included in the final review. Three main research strategies (the development of novel technologies, broad biomarker panels, and targeted approaches) identified a number of potential biomarkers for diabetes including miR-126, C-reactive protein, 2-aminoadipic acid and betatrophin.

CONCLUSION

The most promising research avenue identified is the detection and quantification of micro RNA. Further, the utilisation of functionalised electrodes as a means to detect biomarker compounds also warrants attention.

Molecular Approaches in HFpEF: MicroRNAs and iPSC-Derived Cardiomyocytes

Heart failure with preserved left ventricular ejection fraction (HFpEF) has emerged as one of the largest unmet needs in cardiovascular medicine. HFpEF is increasing in prevalence and causes significant morbidity, mortality, and health care resource utilization. Patients have multiple co-morbidities which contribute to the disease complexity. To date, no effective treatment for HFpEF has been identified. The paucity of cardiac biopsies from this patient population and the absence of well-accepted animal models limit our understanding of the underlying molecular mechanisms of HFpEF. In this review, we discuss combining state-of-the-art technologies of microRNA profiling and human induced pluripotent cell-derived cardiomyocytes (iPSC-CMs) in order to uncover novel molecular pathways that may contribute to the development of HFpEF. Here, we focus the advantages and limitations of microRNA profiling and iPSC-CMs as a disease model system to discover molecular mechanisms in HFpEF.

Regulatory Roles of MicroRNAs in Diabetes

MicroRNAs (miRNAs), a class of endogenous small noncoding RNAs in eukaryotes, have been recognized as significant regulators of gene expression through post-transcriptional mechanisms. To date, >2000 miRNAs have been identified in the human genome, and they orchestrate a variety of biological and pathological processes. Disruption of miRNA levels correlates with many diseases, including diabetes mellitus, a complex multifactorial metabolic disorder affecting >400 million people worldwide. miRNAs are involved in the pathogenesis of diabetes mellitus by affecting pancreatic β-cell functions, insulin resistance, or both. In this review, we summarize the investigations of the regulatory roles of important miRNAs in diabetes, as well as the potential of circulating miRNAs as diagnostic markers for diabetes mellitus.