Serum microRNA-1 and microRNA-133a levels reflect myocardial steatosis in uncomplicated type 2 diabetes

Interplay Between TGF-β Signaling and MicroRNA in Diabetic Cardiomyopathy

In diabetic patients, concomitant cardiovascular disease is the main factor contributing to their morbidity and mortality. Diabetic cardiomyopathy (DCM) is a form of cardiovascular disease associated with diabetes that can result in heart failure. Transforming growth factor-β (TGF-β) isoforms play a crucial role in heart remodeling and repair and are elevated and activated in myocardial disorders. Alterations in certain microRNAs (miRNA) are closely related to diabetic cardiomyopathy. One or more miRNA molecules target the majority of TGF-β pathway components, and TGF-β directly or via SMADs controls miRNA synthesis. Based on these interactions, this review discusses potential cross-talk between TGF-β signaling and miRNA in DCM in order to investigate the creation of potential therapeutic targets.

Start small, think big: MicroRNAs in diabetes mellitus and relevant cardiorenal-liver metabolic health spectrum

Diabetes mellitus (DM), co-existing with metabolic disorder of cardio-renal-liver, is one of the most difficult problems in medicine that attracts global concern with high mortality. MicroRNAs (miRNAs) are a class of small non-coding RNA molecules that negatively regulates gene expression and exerts active against a large proportion of the transcriptome, due to their high evolutionary conservation. Emerging evidence prove that miRNAs are involved in the pathogenesis of DM and associated metabolic disorders, manifested by their variable alteration in the blood, urine, tissues, or organs, principally contributing to modulate the interconnections between DM and cardio-renal-liver metabolism. Mechanistically, miRNAs regulate various biological processes, such as metabolism of insulin, lipid, glucose, inflammatory response, fibrosis, oxidative stress, apoptosis, and angiogenesis, etc. This review emphasizes the function of miRNAs and highlights the physiopathological regulation of miRNA in DM and related complications, especially the dysfunction of cardiovascular system, kidneys, and liver, with the aim of providing promising biomarkers for assisting early diagnosis of DM with cardio-renal-liver- specific metabolic disorders, as well as for the development of miRNA-targeting agents.

Mechanistic insight into the role of cardiac-enriched microRNAs in diabetic heart injury

Cardiovascular complications, particularly diabetic cardiomyopathy (DCM), are the primary causes of morbidity and mortality among individuals with diabetes. Hyperglycemia associated with diabetes leads to cardiomyocyte hypertrophy, apoptosis, and myocardial fibrosis, culminating in heart failure (HF). Patients with diabetes face a 2-4 times greater risk of developing HF compared with those without diabetes. Consequently, there is a growing interest in exploring the molecular mechanisms that contribute to the development of DCM. MicroRNAs (miRNAs) are short, single-stranded, noncoding RNA molecules that participate in the maintenance of physiological homeostasis through the regulation of essential processes such as metabolism, cell proliferation, and apoptosis. At the posttranscriptional level, miRNAs modulate gene expression by binding directly to genes' mRNAs. Multiple cardiac-enriched miRNAs were reported to be dysregulated under diabetic conditions. Different studies revealed the role of specific miRNAs in the pathogenesis of diabetes and related cardiovascular complications, including cardiomyocyte hypertrophy and fibrosis, mitochondrial dysfunction, metabolic impairment, inflammatory response, or cardiomyocyte death. Circulating miRNAs have been shown to represent the potential biomarkers for early detection of diabetic heart injury. A deeper understanding of miRNAs and their role in diabetes-related pathophysiological processes could lead to new therapeutic strategies for addressing cardiac complications associated with diabetes.

Shared Genomic Features Between Lung Adenocarcinoma and Type 2 Diabetes: A Bioinformatics Study

BACKGROUND

Lung adenocarcinoma (LUAD) is a common histopathological variant of non-small cell lung cancer. Individuals with type 2 diabetes (T2DM) face an elevated risk of developing LUAD. We examined the common genomic characteristics between LUAD and T2DM through bioinformatics analysis.

METHODS

We acquired the GSE40791, GSE25724, GSE10072, and GSE71416 datasets. Differentially expressed genes (DEGs) were identified through R software, particularly its version 4.1.3 and analyzed via gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Subsequently, we analyzed the relationship between immune cell infiltration and DEGs. we constructed a protein-protein interaction network using STRING and visualized it with Cytoscape. Moreover, gene modules were identified utilizing the MCODE plugin, and hub genes were selected through the CytoHubba plugin. Additionally, we evaluated the predictive significance of hub genes using receiver operating characteristic curves and identified the final central hub genes. Finally, we forecasted the regulatory networks of miRNA and transcription factors for the central hub genes.

RESULTS

A total of 748 DEGs were identified. Analysis of immune infiltration showed a notable accumulation of effector-memory CD8 T cells, T follicular helper cells, type 1 T helper cells, activated B cells, natural killer cells, macrophages, and neutrophils in both LUAD and T2DM. Moreover, these DEGs were predominantly enriched in immune-related pathways, including the positive regulation of I-κB kinase/NF-κB signaling, positive regulation of immunoglobulin production, cellular response to interleukin-7, and cellular response to interleukin-4. The TGF-β signaling pathway was significantly important among them. Additionally, seven hub genes were identified, including ATR, RFC4, MCM2, NUP155, NUP107, NUP85, and NUP37. Among them, ATR, RFC4, and MCM2 were identified as pivotal hub genes. Additionally, hsa-mir147a, hsa-mir16-5p, and hsa-mir-1-3p were associated with LUAD and T2DM. SP1 (specific protein 1) and KDM5A (lysine-specific demethylase 5A) regulated MCM2, ATR, and RFC4.

CONCLUSIONS

Our study elucidates the common mechanisms of immune response, TGF-β signaling pathway, and natural killer cells in LUAD and T2DM, and identifies ATR, RFC4, and MCM2 as key potential biomarkers and therapeutic targets for the comorbidity of these two conditions.

MicroRNAs in atrial fibrillation - have we discovered the Holy Grail or opened a Pandora's box?

Atrial fibrillation (AF) causes a heavy socio-economic burden on healthcare systems around the globe. Identification of new preventive, diagnostic, and treatment methods is imperative. In recent years, special attention has been paid to microRNAs (miRNAs) as potential regulators of AF pathogenesis. Through post-transcriptional regulation of genes, miRNAs have been shown to play crucial roles in AF-related structural and electrical atrial remodeling. Altered expression of different miRNAs has been related to proarrhythmic changes in the duration of action potentials and atrial fibrosis. In clinical studies, miRNA changes have been associated with AF, whereas in experimental studies miRNA manipulation has emerged as a potential therapeutic approach. It would appear that, with the advent of miRNAs, we may have found the Holy Grail, and that efficient and personalized AF therapy may be one step away. Yet, the clinical relevance of miRNA evaluation and manipulation remains questionable. Studies have identified numerous miRNAs associated with AF, but none of them have shown sufficient specificity for AF. MicroRNAs are not gene-specific but regulate the expression of a myriad of genes. Cardiac and non-cardiac off-target effects may thus occur following miRNA manipulation. A Pandora's box might thus have opened with the advent of these sophisticated molecules. In this paper, we provide a critical analysis of the clinical and experimental, epidemiological and mechanistic data linking miRNAs to AF, we discuss the most promising miRNA therapeutic approaches, we emphasize a number of questions that remain to be answered, and we identify hotspots for future research.

Effect of green coffee on miR-133a, miR-155 and inflammatory biomarkers in obese individuals

OBJECTIVES

Metabolic syndrome is a cluster of conditions that increases the risk of atherosclerotic cardiovascular diseases. The current study was a randomized, double blind, placebo-controlled study that aimed to determine the impact of green coffee (GC) in obese patients with metabolic syndrome through analysis of miRNA-155, miRNA-133a and the inflammatory biomarkers such as resistin, TNF-α, total sialic acid, homocysteine, high sensitivity C-reactive protein (hs-CRP), and the anti-inflammatory cytokine, adiponectin.

METHODS

One hundred-sixty obese patients were randomly supplemented either with GC capsules (800 mg) or placebo daily for six months. Both groups were advised to take a balanced diet. Blood samples were collected at baseline and after six months of supplementation.

RESULTS

GC supplementation for 6 months reduced BMI (p = 0.002), waist circumference (p = 0.038), blood glucose (p = 0.002), HbA1c% (p = 0.000), Insulin (p = 0.000), systolic blood pressure (p = 0.005), diastolic BP (p = 0.001) compared with placebo. GC significantly decreased total cholesterol (TC, p = 0.000), LDL-C (p = 0.001), triglycerides (TG, p = 0.002) and increased HDL-C (p = 0.008) compared with placebo group. In addition, GC significantly (p ≤ 0.005) reduced total sialic acid, homocysteine, resistin, TNF-α, hs-CRP and the oxidative stress marker malondialdehyde (MDA), but increased serum adiponectin (p = 0.000) compared to placebo group. There was a significant reduction in the gene expression of miR-133a (p = 0.000) in GC group as compared with baseline levels and with the control placebo group (p = 0.001) after 6 months.

CONCLUSION

GC administration modulated metabolic syndrome by decreasing BMI, high BP, blood glucose, dyslipidemia, miRNA-133a and inflammatory biomarkers that constitute risk factors for cardiovascular diseases.

CLINICALTRIALS

gov registration No. is NCT05688917.

MicroRNA-34a and promoter methylation contribute to peroxisome proliferator-activated receptor gamma gene expression in patients with type 2 diabetes

AIMS

This study aimed to investigate the roles of DNA methylation and miR-34a in the regulation of peroxisome proliferator-activated receptor gamma (PPARγ) in patients with type 2 diabetes (T2D).

METHODS

We investigated the methylation status of four regions of the PPARγ promoter and PPARγ expression in a panel of 84 T2D patients using methylation-specific PCR (MSP) and RT-qPCR, respectively. Moreover, we quantified DNA methyltransferases (DNMTs) expression and global DNA methylation levels by RT-qPCR and ELISA, respectively. We measured the expression levels of miR-34a and protein expression of PPARγ by stem-loop RT-qPCR and ELISA, respectively.

RESULTS

We found significant DNA hypermethylation in the R2 and R3 regions of the PPARγ promoter in people with diabetes. Functionally, this was associated with a significant reduction in PPARγ expression. In addition, we observed a significant increase in 5-methylcytosine levels in people with diabetes. A marked increase in circulating miR-34a in the early stages of T2D (up to 10 years) and a significant decrease in circulating miR-34a with increasing diabetes duration from 10 years after the onset of diabetes. Interestingly, upregulation of DNA methyltransferases 1 (DNMT1), DNMT3A, and DNMT3B was observed in people with diabetes, and the average expression of DNMTs was negatively correlated with circulating miR-34a levels. In contrast, the serum protein level of PPARγ, a direct target of miR-34a, increased considerably with diabetes duration and showed a negative correlation with circulating miR-34a, cholesterol, triglyceride, and low-density lipoprotein.

CONCLUSION

PPARγ promoter hypermethylation and miR-34a upregulation are associated with T2D pathogenesis through PPARγ dysregulation.

Identifying miRNA Signatures Associated with Pancreatic Islet Dysfunction in a FOXA2-Deficient iPSC Model

The pathogenesis of diabetes involves complex changes in the expression profiles of mRNA and non-coding RNAs within pancreatic islet cells. Recent progress in induced pluripotent stem cell (iPSC) technology have allowed the modeling of diabetes-associated genes. Our recent study using FOXA2-deficient human iPSC models has highlighted an essential role for FOXA2 in the development of human pancreas. Here, we aimed to provide further insights on the role of microRNAs (miRNAs) by studying the miRNA-mRNA regulatory networks in iPSC-derived islets lacking the FOXA2 gene. Consistent with our previous findings, the absence of FOXA2 significantly downregulated the expression of islet hormones, INS, and GCG, alongside other key developmental genes in pancreatic islets. Concordantly, RNA-Seq analysis showed significant downregulation of genes related to pancreatic development and upregulation of genes associated with nervous system development and lipid metabolic pathways. Furthermore, the absence of FOXA2 in iPSC-derived pancreatic islets resulted in significant alterations in miRNA expression, with 61 miRNAs upregulated and 99 downregulated. The upregulated miRNAs targeted crucial genes involved in diabetes and pancreatic islet cell development. In contrary, the absence of FOXA2 in islets showed a network of downregulated miRNAs targeting genes related to nervous system development and lipid metabolism. These findings highlight the impact of FOXA2 absence on pancreatic islet development and suggesting intricate miRNA-mRNA regulatory networks affecting pancreatic islet cell development.

A Review of MicroRNAs and lncRNAs in Atherosclerosis as Well as Some Major Inflammatory Conditions Affecting Atherosclerosis

It is generally accepted that atherosclerosis is a chronic inflammatory disease. The link between atherosclerosis and other inflammatory diseases such as psoriasis, type 2 diabetes mellitus (T2DM), and rheumatoid arthritis (RA) via metabolic, inflammatory, and immunoregulatory pathways is well established. The aim of our review was to summarize the associations between selected microRNAs (miRs) and long non-coding RNAs (lncRNAs) and atherosclerosis, psoriasis, T2DM, and RA. We reviewed the role of miR-146a, miR-210, miR-143, miR-223, miR-126, miR-21, miR-155, miR-145, miR-200, miR-133, miR-135, miR-221, miR-424, let-7, lncRNA-H19, lncRNA-MEG3, lncRNA-UCA1, and lncRNA-XIST in atherosclerosis and psoriasis, T2DM, and RA. Extracellular vesicles (EVs) are a method of intracellular signal transduction. Their function depends on surface expression, cargo, and the cell from which they originate. The majority of the studies that investigated lncRNAs and some miRs had relatively small sample sizes, which limits the generalizability of their findings and indicates the need for more research. Based on the studies reviewed, miR-146a, miR-155, miR-145, miR-200, miR-133, and lncRNA-H19 are the most promising potential biomarkers and, possibly, therapeutic targets for atherosclerosis as well as T2DM, RA, and psoriasis.

The Role of Adipose Tissue-derived Exosomes in Chronic Metabolic Disorders

Excessive fat deposition in obese subjects promotes the occurrence of metabolic diseases, such as type 2 diabetes mellitus (T2DM), cardiovascular diseases, and non-alcoholic fatty liver disease (NAFLD). Adipose tissue is not only the main form of energy storage but also an endocrine organ that not only secretes adipocytokines but also releases many extracellular vesicles (EVs) that play a role in the regulation of whole-body metabolism. Exosomes are a subtype of EVs, and accumulating evidence indicates that adipose tissue exosomes (AT Exos) mediate crosstalk between adipose tissue and multiple organs by being transferred to targeted cells or tissues through paracrine or endocrine mechanisms. However, the roles of AT Exos in crosstalk with metabolic organs remain to be fully elucidated. In this review, we summarize the latest research progress on the role of AT Exos in the regulation of metabolic disorders. Moreover, we discuss the potential role of AT Exos as biomarkers in metabolic diseases and their clinical application.

Extracellular Vesicles in Metabolic and Vascular Insulin Resistance

BACKGROUND

Insulin resistance is a major etiological factor in obesity, type 2 diabetes, and cardiovascular disease (CVD). Endothelial dysfunction may precede impairments in insulin-stimulated glucose uptake, thereby making it a key feature in development of CVD. However, the mechanism by which vascular tissue becomes dysfunctional is not clear.

SUMMARY

Extracellular vesicles (EVs) have emerged as potential mediators of insulin resistance and vascular dysfunction. EVs are membrane-bound particles released by tissues following cellular stress or activation. They carry "cargo" (e.g., insulin signaling proteins, eNOS-nitric oxide, and miRNA) that are believed to promote inter-cellular and interorgan communications. Herein, we review the underlying physiology of EVs in relation to type 2 diabetes and CVD risk. Specifically, we discuss how EVs may modulate metabolic (e.g., skeletal muscle, liver, and adipose) insulin sensitivity, and propose that EVs may modulate vascular insulin action to influence both endothelial function and arterial stiffness. We lastly identify how EVs may play a unique role following exercise to promote metabolic and vascular insulin sensitivity changes.

KEY MESSAGE

Gaining insight toward insulin-mediated EV mechanism has potential to identify novel pathways regulating cardiometabolic health and provide foundation for examining EVs as unique biomarkers and targets to prevent and/or treat chronic diseases.

Mapping novel QTL and fine mapping of previously identified QTL associated with glucose tolerance using the collaborative cross mice

A chronic metabolic illness, type 2 diabetes (T2D) is a polygenic and multifactorial complicated disease. With an estimated 463 million persons aged 20 to 79 having diabetes, the number is expected to rise to 700 million by 2045, creating a significant worldwide health burden. Polygenic variants of diabetes are influenced by environmental variables. T2D is regarded as a silent illness that can advance for years before being diagnosed. Finding genetic markers for T2D and metabolic syndrome in groups with similar environmental exposure is therefore essential to understanding the mechanism of such complex characteristic illnesses. So herein, we demonstrated the exclusive use of the collaborative cross (CC) mouse reference population to identify novel quantitative trait loci (QTL) and, subsequently, suggested genes associated with host glucose tolerance in response to a high-fat diet. In this study, we used 539 mice from 60 different CC lines. The diabetogenic effect in response to high-fat dietary challenge was measured by the three-hour intraperitoneal glucose tolerance test (IPGTT) test after 12 weeks of dietary challenge. Data analysis was performed using a statistical software package IBM SPSS Statistic 23. Afterward, blood glucose concentration at the specific and between different time points during the IPGTT assay and the total area under the curve (AUC0-180) of the glucose clearance was computed and utilized as a marker for the presence and severity of diabetes. The observed AUC0-180 averages for males and females were 51,267.5 and 36,537.5 mg/dL, respectively, representing a 1.4-fold difference in favor of females with lower AUC0-180 indicating adequate glucose clearance. The AUC0-180 mean differences between the sexes within each specific CC line varied widely within the CC population. A total of 46 QTL associated with the different studied phenotypes, designated as T2DSL and its number, for Type 2 Diabetes Specific Locus and its number, were identified during our study, among which 19 QTL were not previously mapped. The genomic interval of the remaining 27 QTL previously reported, were fine mapped in our study. The genomic positions of 40 of the mapped QTL overlapped (clustered) on 11 different peaks or close genomic positions, while the remaining 6 QTL were unique. Further, our study showed a complex pattern of haplotype effects of the founders, with the wild-derived strains (mainly PWK) playing a significant role in the increase of AUC values.

Unraveling the Signaling Dynamics of Small Extracellular Vesicles in Cardiac Diseases

Effective intercellular communication is essential for cellular and tissue balance maintenance and response to challenges. Cellular communication methods involve direct cell contact or the release of biological molecules to cover short and long distances. However, a recent discovery in this communication network is the involvement of extracellular vesicles that host biological contents such as proteins, nucleic acids, and lipids, influencing neighboring cells. These extracellular vesicles are found in body fluids; thus, they are considered as potential disease biomarkers. Cardiovascular diseases are significant contributors to global morbidity and mortality, encompassing conditions such as ischemic heart disease, cardiomyopathies, electrical heart diseases, and heart failure. Recent studies reveal the release of extracellular vesicles by cardiovascular cells, influencing normal cardiac function and structure. However, under pathological conditions, extracellular vesicles composition changes, contributing to the development of cardiovascular diseases. Investigating the loading of molecular cargo in these extracellular vesicles is essential for understanding their role in disease development. This review consolidates the latest insights into the role of extracellular vesicles in diagnosis and prognosis of cardiovascular diseases, exploring the potential applications of extracellular vesicles in personalized therapies, shedding light on the evolving landscape of cardiovascular medicine.

The role of exosomes and exosomal microRNA in diabetic cardiomyopathy

Diabetic cardiomyopathy, a formidable cardiovascular complication linked to diabetes, is witnessing a relentless surge in its incidence. Despite extensive research efforts, the primary pathogenic mechanisms underlying this condition remain elusive. Consequently, a critical research imperative lies in identifying a sensitive and dependable marker for early diagnosis and treatment, thereby mitigating the onset and progression of diabetic cardiomyopathy (DCM). Exosomes (EXOs), minute vesicles enclosed within bilayer lipid membranes, have emerged as a fascinating frontier in this quest, capable of transporting a diverse cargo that mirrors the physiological and pathological states of their parent cells. These exosomes play an active role in the intercellular communication network of the cardiovascular system. Within the realm of exosomes, MicroRNA (miRNA) stands as a pivotal molecular player, revealing its profound influence on the progression of DCM. This comprehensive review aims to offer an introductory exploration of exosome structure and function, followed by a detailed examination of the intricate role played by exosome-associated miRNA in diabetic cardiomyopathy. Our ultimate objective is to bolster our comprehension of DCM diagnosis and treatment strategies, thereby facilitating timely intervention and improved outcomes.

Extracellular vesicles in cardiovascular diseases: From pathophysiology to diagnosis and therapy

Extracellular vesicles (EVs), encompassing exosomes, microvesicles (MVs), and apoptotic bodies (ABs), are cell-derived heterogeneous nanoparticles with a pivotal role in intercellular communication. EVs are enclosed by a lipid-bilayer membrane to escape enzymatic degradation. EVs contain various functional molecules (e.g., nucleic acids, proteins, lipids and metabolites) which can be transferred from donor cells to recipient cells. EVs provide many advantages including accessibility, modifiability and easy storage, stability, biocompatibility, heterogeneity and they readily penetrate through biological barriers, making EVs ideal and promising candidates for diagnosis/prognosis biomarkers and therapeutic tools. Recently, EVs were implicated in both physiological and pathophysiological settings of cardiovascular system through regulation of cell-cell communication. Numerous studies have reported a role for EVs in the pathophysiological progression of cardiovascular diseases (CVDs) and have evaluated the utility of EVs for the diagnosis/prognosis and therapeutics of CVDs. In this review, we summarize the biology of EVs, evaluate the perceived biological function of EVs in different CVDs along with a consideration of recent progress for the application of EVs in diagnosis/prognosis and therapies of CVDs.

Network analysis identifies circulating miR-155 as predictive biomarker of type 2 diabetes mellitus development in obese patients: a pilot study

Obesity is the main risk factor for many non-communicable diseases. In clinical practice, unspecific markers are used for the determination of metabolic alterations and inflammation, without allowing the characterization of subjects at higher risk of complications. Circulating microRNAs represent an attractive approach for early screening to identify subjects affected by obesity more at risk of developing connected pathologies. The aim of this study was the identification of circulating free and extracellular vesicles (EVs)-embedded microRNAs able to identify obese patients at higher risk of type 2 diabetes (DM2). The expression data of circulating microRNAs derived from obese patients (OB), with DM2 (OBDM) and healthy donors were combined with clinical data, through network-based methodology implemented by weighted gene co-expression network analysis. The six circulating microRNAs overexpressed in OBDM patients were evaluated in a second group of patients, confirming the overexpression of miR-155-5p in OBDM patients. Interestingly, the combination of miR-155-5p with serum levels of IL-8, Leptin and RAGE was useful to identify OB patients most at risk of developing DM2. These results suggest that miR-155-5p is a potential circulating biomarker for DM2 and that the combination of this microRNA with other inflammatory markers in OB patients can predict the risk of developing DM2.

Zinc Improves Semen Parameters in High-Fat Diet-Induced Male Rats by Regulating the Expression of LncRNA in Testis Tissue

This study aimed to identify differentially expressed LncRNAs in testis tissue of male rats induced by high-fat diet and their changes after zinc supplementation, by constructing a high-fat feeding rat model, and then supplemented with zinc, and observed the expression of LncRNA in three groups of normal, high-fat fed, and zinc-intervened rats. Experimental studies show that the semen parameters of male rats with high-fat diet were decreased but recovered after zinc supplementation, and the related LncRNA also changed. Zinc may improve the high-fat diet-induced reduction of semen parameters by changing the expression of related LncRNA.

Exosomes as biomarkers and therapy in type 2 diabetes mellitus and associated complications

Type 2 diabetes mellitus (T2DM) is one of the most prevalent metabolic disorders worldwide. However, T2DM still remains underdiagnosed and undertreated resulting in poor quality of life and increased morbidity and mortality. Given this ongoing burden, researchers have attempted to locate new therapeutic targets as well as methodologies to identify the disease and its associated complications at an earlier stage. Several studies over the last few decades have identified exosomes, small extracellular vesicles that are released by cells, as pivotal contributors to the pathogenesis of T2DM and its complications. These discoveries suggest the possibility of novel detection and treatment methods. This review provides a comprehensive presentation of exosomes that hold potential as novel biomarkers and therapeutic targets. Additional focus is given to characterizing the role of exosomes in T2DM complications, including diabetic angiopathy, diabetic cardiomyopathy, diabetic nephropathy, diabetic peripheral neuropathy, diabetic retinopathy, and diabetic wound healing. This study reveals that the utilization of exosomes as diagnostic markers and therapies is a realistic possibility for both T2DM and its complications. However, the majority of the current research is limited to animal models, warranting further investigation of exosomes in clinical trials. This review represents the most extensive and up-to-date exploration of exosomes in relation to T2DM and its complications.

Therapeutic Potential of EVs: Targeting Cardiovascular Diseases

Due to their different biological functions, extracellular vesicles (EVs) have great potential from a therapeutic point of view. They are released by all cell types, carrying and delivering different kinds of biologically functional cargo. Under pathological events, cells can increase their secretion of EVs and can release different amounts of cargo, thus making EVs great biomarkers as indicators of pathological progression. Moreover, EVs are also known to be able to transport and deliver cargo to different recipient cells, having an important role in cellular communication. Interestingly, EVs have recently been explored as biological alternatives for the delivery of therapeutics, being considered natural drug delivery carriers. Because cardiovascular disorders (CVDs) are the leading cause of death worldwide, in this review, we will discuss the up-to-date knowledge regarding the biophysical properties and biological components of EVs, focusing on myocardial infarction, diabetic cardiomyopathy, and sepsis-induced cardiomyopathy, three very different types of CVDs.

The role of extracellular vesicle-derived miRNAs in adipose tissue function and metabolic health

Extracellular vesicles (EVs) are nanometer size lipid particles that are released from virtually every cell type. Recent studies have shown that miRNAs carried by EVs play important roles in intercellular and interorgan communication. In the context of obesity and insulin resistance, EV-derived miRNAs functionally bridge major metabolic organs, including the adipose tissue, skeletal muscle, liver, and pancreas, to regulate insulin secretion and signaling. As a result, many of these EV-derived miRNAs have been proposed as potential disease biomarkers and/or therapeutic agents. However, the field's knowledge of EV miRNA-mediated regulation of mammalian metabolism is still in its infancy. Here, we review the evidence indicating that EV-derived miRNAs provide cell-to-cell and organ-to-organ communication to support metabolic health, highlight the potential medical relevance of these discoveries, and discuss the most important knowledge gaps and future directions for this field.

Emerging Biomarkers of Acute Myocardial Infarction, An Overview of the Newest MicroRNAs

Globally, acute myocardial infarction (AMI) is the leading cause of death. Early and precise diagnosis is essential for medical care to enhance prognoses and reduce mortality. The diagnosis of AMI relies primarily on conventional circulating biomarkers. However, these markers have many drawbacks. Non-coding RNAs (ncRNAs) form a significant fraction of the transcriptome and have been shown to be essential for many biological processes, including the pathogenesis of the disease. ncRNAs can be utilized as biomarkers due to their important role in the disease's development. The current manuscript describes recent progress on the role of ncRNAs as new AMI biomarkers.

Emerging Biomarkers of Acute Myocardial Infarction, An Overview of the Newest MicroRNAs

Globally, acute myocardial infarction (AMI) is the leading cause of death. Early and precise diagnosis is essential for medical care to enhance prognoses and reduce mortality. The diagnosis of AMI relies primarily on conventional circulating biomarkers. However, these markers have many drawbacks. Non-coding RNAs (ncRNAs) form a significant fraction of the transcriptome and have been shown to be essential for many biological processes, including the pathogenesis of the disease. ncRNAs can be utilized as biomarkers due to their important role in the disease's development. The current manuscript describes recent progress on the role of ncRNAs as new AMI biomarkers.

Circulating miRNA expression in long-standing type 1 diabetes mellitus

Type 1 diabetes is a chronic autoimmune disease which results in inefficient regulation of glucose homeostasis and can lead to different vascular comorbidities through life. In this study we aimed to analyse the circulating miRNA expression profile of patients with type 1 diabetes, and with no other associated pathology. For this, fasting plasma was obtained from 85 subjects. Next generation sequencing analysis was firstly performed to identify miRNAs that were differentially expressed between groups (20 patients vs. 10 controls). hsa-miR-1-3p, hsa-miR-200b-3p, hsa-miR-9-5p, and hsa-miR-1200 expression was also measured by Taqman RT-PCR to validate the observed changes (34 patients vs. 21 controls). Finally, through a bioinformatic approach, the main pathways affected by the target genes of these miRNAs were studied. Among the studied miRNAs, hsa-miR-1-3p expression was found significantly increased in patients with type 1 diabetes compared to controls, and positively correlated with glycated haemoglobin levels. Additionally, by using a bioinformatic approach, we could observe that changes in hsa-miR-1-3p directly affect genes involved in vascular development and cardiovascular pathologies. Our results suggest that, circulating hsa-miR-1-3p in plasma, together with glycaemic control, could be used as prognostic biomarkers in type 1 diabetes, helping to prevent the development of vascular complications in these patients.

Cardiovascular complications of diabetes: role of non-coding RNAs in the crosstalk between immune and cardiovascular systems

Diabetes mellitus, a group of metabolic disorders characterized by high levels of blood glucose caused by insulin defect or impairment, is a major risk factor for cardiovascular diseases and related mortality. Patients with diabetes experience a state of chronic or intermittent hyperglycemia resulting in damage to the vasculature, leading to micro- and macro-vascular diseases. These conditions are associated with low-grade chronic inflammation and accelerated atherosclerosis. Several classes of leukocytes have been implicated in diabetic cardiovascular impairment. Although the molecular pathways through which diabetes elicits an inflammatory response have attracted significant attention, how they contribute to altering cardiovascular homeostasis is still incompletely understood. In this respect, non-coding RNAs (ncRNAs) are a still largely under-investigated class of transcripts that may play a fundamental role. This review article gathers the current knowledge on the function of ncRNAs in the crosstalk between immune and cardiovascular cells in the context of diabetic complications, highlighting the influence of biological sex in such mechanisms and exploring the potential role of ncRNAs as biomarkers and targets for treatments. The discussion closes by offering an overview of the ncRNAs involved in the increased cardiovascular risk suffered by patients with diabetes facing Sars-CoV-2 infection.

MicroRNA-mediated control of myocardial infarction in diabetes

Diabetes mellitus is a global public health problem whose cases will continue to rise along with the progressive increase in obesity and the aging of the population. People with diabetes exhibit higher risk of cardiovascular complications, especially myocardial infarction (MI). microRNAs (miRNAs) are evolutionary conserved small non-coding RNAs involved in the regulation of biological processes by interfering in gene expression at the post-transcriptional level. Accumulating studies in the last two decades have uncovered the role of stage-specific miRNAs associated with key pathobiological events observed in the hearts of people with diabetes and MI, including cardiomyocyte death, angiogenesis, inflammatory response, myocardial remodeling, and myocardial lipotoxicity. A better understanding of the importance of these miRNAs and their targets may provide novel opportunities for RNA-based therapeutic interventions to address the increased risk of MI in diabetes.

Non-coding RNAs regulating mitochondrial function in cardiovascular diseases

Cardiovascular disease (CVD) is the leading cause of disease-related death worldwide and a significant obstacle to improving patients' health and lives. Mitochondria are core organelles for the maintenance of myocardial tissue homeostasis, and their impairment and dysfunction are considered major contributors to the pathogenesis of various CVDs, such as hypertension, myocardial infarction, and heart failure. However, the exact roles of mitochondrial dysfunction involved in CVD pathogenesis remain not fully understood. Non-coding RNAs (ncRNAs), particularly microRNAs, long non-coding RNAs, and circular RNAs, have been shown to be crucial regulators in the initiation and development of CVDs. They can participate in CVD progression by impacting mitochondria and regulating mitochondrial function-related genes and signaling pathways. Some ncRNAs also exhibit great potential as diagnostic and/or prognostic biomarkers as well as therapeutic targets for CVD patients. In this review, we mainly focus on the underlying mechanisms of ncRNAs involved in the regulation of mitochondrial functions and their role in CVD progression. We also highlight their clinical implications as biomarkers for diagnosis and prognosis in CVD treatment. The information reviewed herein could be extremely beneficial to the development of ncRNA-based therapeutic strategies for CVD patients.

Exosomal non coding RNAs as a novel target for diabetes mellitus and its complications

Diabetes mellitus (DM) is a first-line priority among the problems facing medical science and public health in almost all countries of the world. The main problem of DM is the high incidence of damage to the cardiovascular system, which in turn leads to diseases such as myocardial infarction, stroke, gangrene of the lower extremities, blindness and chronic renal failure. As a result, the study of the molecular genetic mechanisms of the pathogenesis of DM is of critical importance for the development of new diagnostic and therapeutic strategies. Molecular genetic aspects of the etiology and pathogenesis of diabetes mellitus are intensively studied in well-known laboratories around the world. One of the strategies in this direction is to study the role of exosomes in the pathogenesis of DM. Exosomes are microscopic extracellular vesicles with a diameter of 30-100 nm, released into the intercellular space by cells of various tissues and organs. The content of exosomes depends on the cell type and includes mRNA, non-coding RNAs, DNA, and so on. Non-coding RNAs, a group of RNAs with limited transcriptional activity, have been discovered to play a significant role in regulating gene expression through epigenetic and posttranscriptional modulation, such as silencing of messenger RNA. One of the problems of usage exosomes in DM is the identification of the cellular origin of exosomes and the standardization of protocols for molecular genetic studies in clinical laboratories. In addition, the question of the target orientation of exosomes and their targeted activity requires additional study. Solving these and other problems will make it possible to use exosomes for the diagnosis and delivery of drugs directly to target cells in DM. This study presents an analysis of literature data on the role of exosomes and ncRNAs in the development and progression of DM, as well as the prospects for the use of exosomes in clinical practice in this disease.

Regulation of HIF-1 by MicroRNAs in Various Cardiovascular Diseases

Today, we see an increase in death due to cardiovascular diseases all over the world, which has a lot to do with the regulation of oxygen homeostasis. Also, hypoxia-inducing factor 1 (HIF-1) is considered a vital factor in hypoxia and its physiological and pathological changes. HIF- 1 is involved in cellular activities, including proliferation, differentiation, and cell death in endothelial cells (ECs) and cardiomyocytes. Similar to HIF-1α, which acts as a protective element against various diseases in the cardiovascular system, the protective role of microRNAs (miRNAs) has also been proved using animal models. The number of miRNAs identified in the regulation of gene expression responsive to hypoxia and the importance of investigating the involvement of the non-coding genome in cardiovascular diseases is increasing, which shows the issue's importance. In this study, the molecular regulation of HIF-1 by miRNAs is considered to improve therapeutic approaches in clinical diagnoses of cardiovascular diseases.

Current Insights into miRNA and lncRNA Dysregulation in Diabetes: Signal Transduction, Clinical Trials and Biomarker Discovery

Diabetes is one of the most frequently occurring metabolic disorders, affecting almost one tenth of the global population. Despite advances in antihyperglycemic therapeutics, the management of diabetes is limited due to its complexity and associated comorbidities, including diabetic neuropathy, diabetic nephropathy and diabetic retinopathy. Noncoding RNAs (ncRNAs), including microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), are involved in the regulation of gene expression as well as various disease pathways in humans. Several ncRNAs are dysregulated in diabetes and are responsible for modulating the expression of various genes that contribute to the 'symptom complex' in diabetes. We review various miRNAs and lncRNAs implicated in diabetes and delineate ncRNA biological networks as well as key ncRNA targets in diabetes. Further, we discuss the spatial regulation of ncRNAs and their role(s) as prognostic markers in diabetes. We also shed light on the molecular mechanisms of signal transduction with diabetes-associated ncRNAs and ncRNA-mediated epigenetic events. Lastly, we summarize clinical trials on diabetes-associated ncRNAs and discuss the functional relevance of the dysregulated ncRNA interactome in diabetes. This knowledge will facilitate the identification of putative biomarkers for the therapeutic management of diabetes and its comorbidities. Taken together, the elucidation of the architecture of signature ncRNA regulatory networks in diabetes may enable the identification of novel biomarkers in the discovery pipeline for diabetes, which may lead to better management of this metabolic disorder.

Enhanced genomic stability of new miRNA-regulated oncolytic coxsackievirus B3

Genetic modification of coxsackievirus B3 (CVB3) by inserting target sequences (TS) of tumor-suppressive and/or organ-selective microRNAs (miRs) into viral genome can efficiently eliminate viral pathogenesis without significant impacts on its oncolytic activity. Nonetheless, reversion mutants (loss of miR-TS inserts) were identified as early as day 35 post-injection in ∼40% immunodeficient mice. To improve the stability, here we re-engineered CVB3 by (1) replacing the same length of viral genome at the non-coding region with TS of cardiac-selective miR-1/miR-133 and pancreas-enriched miR-216/miR-375 or (2) inserting the above miR-TS into the coding region (i.e., P1 region) of viral genome. Serial passaging of these newly established miR-CVB3s in cultured cells for 20 rounds demonstrated significantly improved stability compared with the first-generation miR-CVB3 with 5'UTR insertion of miR-TS. The safety and stability of these new miR-CVB3s was verified in immunocompetent mice. Moreover, we showed that these new viruses retained the ability to suppress lung tumor growth in a xenograft mouse model. Finally, we observed that miR-CVB3 with insertion in P1 region was more stable than miR-CVB3 with preserved length of the 5'UTR, whereas the latter displayed significantly higher oncolytic activity. Overall, we presented here valid strategies to enhance the genomic stability of miR-CVB3 for virotherapy.

The role of microRNAs in the pathophysiology, diagnosis, and treatment of diabetic cardiomyopathy

INTRODUCTION

Diabetic cardiomyopathy (DCM) is an end-point macrovascular complication associated with increased morbidity and mortality in 12% of diabetic patients. MicroRNAs (miRNAs) are small noncoding RNAs that can act as cardioprotective or cardiotoxic agents in DCM.

METHODS

We used PubMed as a search engine to collect and analyse data in published articles on the role of miRNAs on the pathophysiology, diagnosis and treatment of DCM.

RESULTS

MiRNAs play an essential role in the pathophysiology, diagnosis and treatment of DCM due to their distinct gene expression patterns in diabetic patients compared to healthy individuals. Advances in gene therapy have led to the discovery of potential circulating miRNAs, which can be used as biomarkers for DCM diagnosis and prognosis. Furthermore, targeted miRNA therapies in preclinical and clinical studies, such as using miRNA mimics and anti-miRNAs, have yielded promising results. Application of miRNA mimics and anti-miRNAs via different nanodrug delivery systems alleviate hypertrophy, fibrosis, oxidative stress and apoptosis of cardiomyocytes.

CONCLUSION

MiRNAs serve as attractive potential targets for DCM diagnosis, prognosis and treatment due to their distinctive expression profile in DCM development.

miR-133a-A Potential Target for Improving Cardiac Mitochondrial Health and Regeneration After Injury

ABSTRACT

The various roles of muscle secretory factors and myokines have been well studied, but in recent decades, the role of myocyte-specific microRNAs (myomiRs) has gained momentum. These myomiRs are known to play regulatory roles in muscle health in general, both skeletal muscle and cardiac muscle. In this review, we have focused on the significance of a myomiR termed miR-133a in cardiovascular health. The available literature supports the claim that miR-133a could be helpful in the healing process of muscle tissue after injury. The protective function could be due to its regulatory effect on muscle or stem cell mitochondrial function. In this review, we have shed light on the protective mechanisms offered by miR-133a. Most of the beneficial effects are due to the presence of miR-133a in circulation or tissue-specific expression. We have also reviewed the potential mechanisms by which miR-133a could interact with cell surface receptors and also transcriptional mechanisms by which they offer cardioprotection and regeneration. Understanding these mechanisms will help in finding an ideal strategy to repair cardiac tissue after injury.

Exosomal microRNAs in diabetic heart disease

Diabetes is a metabolic disorder that affects millions of people worldwide. Diabetic heart disease (DHD) comprises coronary artery disease, heart failure, cardiac autonomic neuropathy, peripheral arterial disease, and diabetic cardiomyopathy. The onset and progression of DHD have been attributed to molecular alterations in response to hyperglycemia in diabetes. In this context, microRNAs (miRNAs) have been demonstrated to have a significant role in the development and progression of DHD. In addition to their effects on the host cells, miRNAs can be released into circulation after encapsulation within the exosomes. Exosomes are extracellular nanovesicles ranging from 30 to 180 nm in diameter secreted by all cell types. They carry diverse cargos that are altered in response to various conditions in their parent cells. Exosomal miRNAs have been extensively studied in recent years due to their role and therapeutic potential in DHD. This review will first provide an overview of exosomes, their biogenesis and function, followed by the role of exosomes in cardiovascular disease and then focuses on the known role of exosomes and associated miRNAs in DHD.

Biomarkers for the prediction of heart failure and cardiovascular events in patients with type 2 diabetes: a position statement from the Heart Failure Association of the European Society of Cardiology

Knowledge on risk predictors of incident heart failure (HF) in patients with type 2 diabetes (T2D) is crucial given the frequent coexistence of the two conditions and the fact that T2D doubles the risk of incident HF. In addition, HF is increasingly being recognized as an important endpoint in trials in T2D. On the other hand, the diagnostic and prognostic performance of established cardiovascular biomarkers may be modified by the presence of T2D. The present position paper, derived by an expert panel workshop organized by the Heart Failure Association of the European Society of Cardiology, summarizes the current knowledge and gaps in evidence regarding the use of a series of different biomarkers, reflecting various pathogenic pathways, for the prediction of incident HF and cardiovascular events in patients with T2D and in those with established HF and T2D.

Dietary Acid Load Modulation of Asthma-Related miRNAs in the Exhaled Breath Condensate of Children

Individual nutrients and bioactive compounds have been implicated in the expression of microRNAs (miRNAs), which are related to inflammation and asthma. However, evidence about the impact of diet is scarce. Therefore, we aimed to assess the association between dietary acid load and asthma-related miRNA in the exhaled breath condensate (EBC) of school-aged children. This cross-sectional analysis included 150 participants aged 7 to 12 years (52% girls) from a nested case–control study, which randomly selected 186 children attending 71 classrooms from 20 public schools located in city of Porto, Portugal. Dietary data were collected by one 24 h-recall questionnaire. Dietary acid load was assessed using the potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores. Based on previous studies, eleven asthma-related miRNAs were chosen and analyzed in EBC by reverse transcription-quantitative real-time PCR. PRAL, NEAP and miRNAs were categorized as high or low according to the median. Logistic regression models were performed to assess the association between dietary acid load scores and miRNAs. Children in high dietary acid load groups (PRAL ≥ 14.43 and NEAP ≥ 55.79 mEq/day) have significantly increased odds of having high miR-133a-3p levels. In conclusion, higher dietary acid loads possibly modulate asthma-related miRNAs of school-aged children.

Regulation of microRNAs in Alzheimer´s disease, type 2 diabetes, and aerobic exercise training

Alzheimer's disease (AD) is the most common type of dementia. The evolution and aggregation of amyloid beta (β) oligomers is linked to insulin resistance in AD, which is also the major characteristic of type 2 diabetes (T2D). Being physically inactive can contribute to the development of AD and/or T2D. Aerobic exercise training (AET), a type of physical exercise, can be useful in preventing or treating the negative outcomes of AD and T2D. AD, T2D and AET can regulate the expression of microRNAs (miRNAs). Here, we review some of the changes in miRNAs expression regulated by AET, AD and T2D. MiRNAs play an important role in the gene regulation of key signaling pathways in both pathologies, AD and T2D. MiRNA dysregulation is evident in AD and has been associated with several neuropathological alterations, such as the development of a reactive gliosis. Expression of miRNAs are associated with many pathophysiological mechanisms involved in T2D like insulin synthesis, insulin resistance, glucose intolerance, hyperglycemia, intracellular signaling, and lipid profile. AET regulates miRNAs levels. We identified 5 miRNAs (miR-21, miR-29a/b, miR-103, miR-107, and miR-195) that regulate gene expression and are modulated by AET on AD and T2D. The identified miRNAs are potential targets to treat the symptoms of AD and T2D. Thus, AET is a non-pharmacological tool that can be used to prevent and fight the negative outcomes in AD and T2D.

Biological Functions and Clinical Prospects of Extracellular Non-Coding RNAs in Diabetic Cardiomyopathy: an Updated Review

Diabetic cardiomyopathy (DCM) is one of the major causes of heart failure in diabetic patients. However, the pathogenesis of diabetic cardiomyopathy has not been fully elucidated. Diagnosis and therapeutic strategy of DCM is still challenging. Various non-coding RNAs (ncRNA) are implicated in the onset and progression of DCM. Interestingly, ncRNAs not only are regulators intracellularly, but also can exist and function in extracellular space. Recent evidences have demonstrated that extracellular ncRNAs play emerging roles in both intracardiac and inter-organ communication during the pathogenesis of DCM; thus, extracellular ncRNAs are attractive diagnostic biomarkers and potential therapeutic targets for DCM. This article will review the current knowledge of the roles of extracellular ncRNAs in DCM, especially focusing on their physio-pathological properties and perspectives of potential clinical translation for biomarkers and therapies. Recent evidences have demonstrated that extracellular ncRNA play emerging roles in both intracardiac and inter-organ communication involved in the pathogenesis of diabetic cardiomyopathy (DCM), thus shown as attractive diagnostic biomarkers and potential therapeutics for DCM. In the current review, we first summarize the progress regarding the paracrine role of extracellular ncRNA in DCM. miRNAs and circRNAs have been shown to mediate the communication among cardiomyocytes, endothelial cells, and vascular smooth muscle cells in the diabetic heart. Subsequently, we systematically describe that extracellular ncRNAs contribute to the crosstalk between the heart and other organs in the context of diabetes. Researches have indicated that miRNAs acted as hepatokines and adipokines to mediates the injure effect of distal organs on hearts. As for clinical application, extracellular ncRNAs are promising biomarker and have therapeutic potential. (Created with BioRender.com).

An Update in Epigenetics in Metabolic-Associated Fatty Liver Disease

Metabolic-associated fatty liver disease (MAFLD) is characterized by hepatic steatosis accompanied by one of three features: overweight or obesity, T2DM, or lean or normal weight with evidence of metabolic dysregulation. It is distinguished by excessive fat accumulation in hepatocytes, and a decrease in the liver's ability to oxidize fats, the accumulation of ectopic fat, and the activation of proinflammatory pathways. Chronic damage will keep this pathophysiologic cycle active causing progression from hepatic steatosis to cirrhosis and eventually, hepatocarcinoma. Epigenetics affecting gene expression without altering DNA sequence allows us to study MAFLD pathophysiology from a different perspective, in which DNA methylation processes, histone modifications, and miRNAs expression have been closely associated with MAFLD progression. However, these considerations also faced us with the circumstance that modifying those epigenetics patterns might lead to MAFLD regression. Currently, epigenetics is an area of great interest because it could provide new insights in therapeutic targets and non-invasive biomarkers. This review comprises an update on the role of epigenetic patterns, as well as innovative therapeutic targets and biomarkers in MAFLD.

MicroRNAs in type 2 diabetes mellitus: potential role of physical exercise

Type 2 diabetes mellitus (T2DM) is a multifactorial metabolic disease, and its prevalence has grown worldwide. Several pathophysiological processes contribute to the development, progression and aggravating of the disease, for example, decreased insulin synthesis and secretion, insulin resistance, inflammation, and apoptosis, all these processes are regulated by various epigenetic factors, including microRNAs (miRNAs). MiRNAs are small non-coding RNAs, which are around 20 nucleotides in length and are regulators of gene expression at the post-transcriptional level, have a specific function of inhibiting or degrading a messenger RNA target. Thus, miRNAs modulate the expression of many associated genes with the pathophysiological processes in T2DM. On the other hand, miRNAs are also modulated through physical exercise (PE), which induces a change in their expression pattern during and after exercise. Some scientific evidence shows that PE modulates miRNAs beneficially and improves the signaling pathway of insulin resistance, however, little is known about the function of PE modulating miRNAs associated with the processes of insulin secretion, inflammation, and apoptosis. Thus, the objective of this review is to identify the miRNAs expression pattern in T2DM and compare it with the exercise-induced miRNAs expression pattern, identifying the signaling pathways that these miRNAs are regulating in the processes of insulin secretion, insulin resistance, inflammation, and apoptosis in T2DM, and how PE may have a potential role in modulating these signal transduction pathways, promoting benefits for patients with T2DM.

Eight weeks of combined exercise training do not alter circulating microRNAs-29a, -133a, -133b, and -155 in young, healthy men

PURPOSE

Individuals with a family history of type 2 diabetes (FH +) have an increased risk of developing type 2 diabetes. Circulating microRNAs (miRNAs) have been implicated as biomarkers of type 2 diabetes risk. Here, we investigated if four circulating miRNAs related to glucose metabolism were altered in men with a FH + and we conducted a preliminary analysis to determine if miRNA expressions were responsive to 8 weeks of combined exercise training.

METHODS

Sixteen young healthy men (mean ± SD; age 22.5 ± 2.5; BMI 26.4 ± 4.0) with FH + or without a family history of type 2 diabetes (FH -) underweight 8 weeks of combined endurance and resistance exercise training (n = 8 FH -; n = 8 FH +). The expression of miR-29a, miR-133a, miR-133b, and miR-155 were measured in serum before and after exercise training. QIAGEN's Ingenuity^® Pathway Analysis was used to examine miRNA target genes and their involvement in glucose metabolism signaling pathways.

RESULTS

There were no differences in miRNA expressions between FH - and FH + . Exercise training did not alter miRNA expressions in either FH - or FH + despite improvements in insulin sensitivity, aerobic capacity, and muscular strength. miR-29a and miR-155 were inversely related to fasting glucose, and miR-133a and miR-133b were negatively correlated with glucose tolerance; however, correlations were not observed with insulin sensitivity.

CONCLUSIONS

The circulating miRNAs- miR-29a, miR-133a, miR-133b, and miR-155 are related to measures of glucose metabolism in healthy, normoglycemic men, but do not reflect peripheral insulin sensitivity or improvements in metabolic health following 8 weeks of combined exercise training.

Diagnostic and Therapeutic Application of Exosomal microRNAs Inducing Inflammation in Type 2 Diabetes Mellitus

Diabetes mellitus is a class of noncommunicable chronic metabolic disorders marked by hyperglycemia due to insulin production, insulin action or both and has reached epidemic levels around the world. The two most frequent types of diabetes are type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). Despite substantial improvements in the knowledge and treatment of DM, the associated incidence and mortality rates remain steadily increased. Reliable markers for the early detection, monitoring and focused treatment of DM are desperately required. Conversely, microRNAs (miRNAs) have received much significance due to their regulatory involvement in gene expression. Fascinatingly, exosomes can be enclosed into miRNAs to transport or distribute them into the target cells or tissues in which they have a physiological regulatory action. Thus, exosomal miRNAs are proving to be important regulators in the establishment and maintenance of DM, however, further mode of action will be needed to investigate in order to fully comprehend the pathophysiological process. Hereby, this review outlines the recent findings on the role of exosomal miRNAs intending to understand the precise function in diagnostic and therapeutic aspects in T2DM disease.

Serum MicroRNA Expression Patterns in Subjects After the 5-km Exercise Are Strongly Associated With Cardiovascular Adaptation

Circulating microRNAs (miRNAs) have been reported dysregulated during exercise. However, the changes of specific serum miRNAs during the 5-km run test with intensity of 51–52% maximum oxygen uptake (V̇O₂max) and their association with traditional cardiovascular-related indicators remain well-characterized. Levels of miR-1, miR-21, miR-146a, miR-155, miR-181, and miR-210 were detected in 120 young subjects before and after the exercise training by quantitative reverse-transcription PCR (RT-qPCR). Besides, the levels of cardiac troponin I (cTNI), myoglobin (Myo), creatine kinase (CK), creatine kinase-MB (CK-MB), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), ischemia-modified albumin (IMA), interleukin-6 (IL-6), and C-reactive protein (CRP) were measured and the correlation between levels of serum miRNAs and biochemical parameters was also analyzed. Compared with resting state, the serum levels of miR-1, miR-146a, miR-155, miR-181, and miR-210 were significantly increased after exercise training. Serum levels of miR-146a, miR-155, and miR-210 after exercise training were positively correlated with Myo, CK-MB, and LDH, respectively, while miR-1, miR-146a, miR-181, and miR-155 were positively correlated with the levels of IL-6. Additionally, all the five miRNAs were negatively correlated with IMA levels. The multivariate logistic regression analysis showed that high levels of miR-146a, AST, LDH, and IL-6 in serum were risk factors, while low IMA contents were a protective factor for cardiovascular adaptation during exercise. In conclusion, the dynamic changes of miRNAs under the condition of the 5-km continuous running contribute to the adaptive regulation of the cardiovascular function of the body.

Exosome microRNAs in Metabolic Syndrome as Tools for the Early Monitoring of Diabetes and Possible Therapeutic Options

Exosomes are nano-sized extracellular vesicles produced and released by almost all cell types. They play an essential role in cell-cell communications by delivering cellular bioactive compounds such as functional proteins, metabolites, and nucleic acids, including microRNA, to recipient cells. Thus, they are involved in various physio-pathological conditions. Exosome-miRNAs are associated with numerous diseases, including type 2 diabetes, a complex multifactorial metabolic disorder linked to obesity. In addition, exosome-miRNAs are emerging as essential regulators in the progression of diabetes, principally for pancreatic β-cell injury and insulin resistance. Here, we have clustered the recent findings concerning exosome-miRNAs associated with β-cell dysfunction to provide a novel approach for the early diagnosis and therapy of diabetes.

Molecular Mechanisms of Nutrient-Mediated Regulation of MicroRNAs in Pancreatic β-cells

Pancreatic β-cells within the islets of Langerhans respond to rising blood glucose levels by secreting insulin that stimulates glucose uptake by peripheral tissues to maintain whole body energy homeostasis. To different extents, failure of β-cell function and/or β-cell loss contribute to the development of Type 1 and Type 2 diabetes. Chronically elevated glycaemia and high circulating free fatty acids, as often seen in obese diabetics, accelerate β-cell failure and the development of the disease. MiRNAs are essential for endocrine development and for mature pancreatic β-cell function and are dysregulated in diabetes. In this review, we summarize the different molecular mechanisms that control miRNA expression and function, including transcription, stability, posttranscriptional modifications, and interaction with RNA binding proteins and other non-coding RNAs. We also discuss which of these mechanisms are responsible for the nutrient-mediated regulation of the activity of β-cell miRNAs and identify some of the more important knowledge gaps in the field.

MicroRNA targets and biomarker validation for diabetes-associated cardiac fibrosis

Cardiac fibrosis is one of the main characteristics of diabetic cardiomyopathy and manifests excessive accumulation of extracellular matrix proteins in the heart. Several signaling pathways have been proposed for pathogenesis of cardiac fibrosis in the diabetic heart. TGF-β/Smad2/3-dependent or independent pathway is the major signaling molecule core in the pathogenesis of cardiac fibrosis. MicroRNAs (miRNAs, miR) are ~22-nuceotide regulatory RNAs that are involved in gene silencing through the degradation of post-transcriptional mRNA or suppression of the expressed proteins. Hyperglycemia in the diabetic heart regulates expression of some miRNAs. Target molecules of miRNAs can be identified through biocomputational database initial screening and dual luciferase assay validation. miR-21, miR-150-5p, miR-155, miR-216a-3p, miR-221-3p, miR-223, and miR-451 were up-regulated in the diabetic heart and promoted cardiac fibrosis through targeting signaling pathways in cardiac fibroblasts, endothelial cells, and cardiac myocytes. miR-15a/-15b, miR-18a-5p, miR-20a-5p, miR-26b-5p, miR-29, miR-133a, miR-141, miR-146, miR-200b, miR-203, miR-222, and miR-551b-5p were down-regulated in the diabetic heart and exhibited anti-fibrosis when they were overexpressed. miRNAs are stable molecules and may reflect the pathological changes of organs. Some miRNAs have been detected in the plasma or serum in patients with diabetes mellitus or heart failure. Exploration of targets and biomarkers of miRNA may provide additional information on pathogenesis and diagnosis of cardiac fibrosis and novel targets to tackle diabetic cardiomyopathy.

Noncoding RNAs and RNA-binding proteins in diabetic wound healing

Poor wound healing is a common complication in diabetic patients. It often leads to intractable infections and lower limb amputations and is associated with cardiovascular morbidity and mortality. NcRNAs, which can regulate gene expression, have emerged as important regulators of various physiological processes. Herein, we summarize the diverse roles of ncRNAs in the key stages of diabetic wound healing, including inflammation, angiogenesis, re-epithelialization, and extracellular matrix remodeling. Meanwhile, the potential use of ncRNAs as novel therapeutic targets for wound healing in diabetic patients is also discussed. In addition, we summarize the role of RNA-binding proteins (RBPs) in the regulation of gene expression and signaling pathways during skin repair, which may provide opportunities for therapeutic intervention for this potentially devastating disease. However, so far, research on the modulated drug based on ncRNAs that lead to significantly altered gene expression in diabetic patients is scarce. We have compiled some drugs that may be able to modulate ncRNAs, which significantly regulate the gene expression in diabetic patients.

Clinical significance of serum miR-129-5p in patients with diabetes mellitus presenting macrovascular complications

BACKGROUND

Diabetic macrovascular complications (DMCs) are the most common complications encountered during the course of diabetes mellitus (DM) with extremely high mortality rates. Therefore, there is an urgent need to identify specific and sensitive biomarkers for the early diagnosis of DMCs.

AIM

To investigate the expression and significance of serum miR-129-5p in patients with DM and macrovascular complications.

METHODS

Serum samples were collected from 36 healthy controls, 58 patients with DM presenting no macrovascular complications, and 62 patients with DMCs. The expression of miR-129-5p was detected using quantitative real-time polymerase chain reaction. Pearson's correlation assay was performed to analyze the correlation between serum miR-129-5p levels and clinical indicators. Receiver operator characteristic (ROC) analysis was conducted to analyze the diagnostic value of serum miR-129-5p in patients with DM or DMCs.

RESULTS

There was a 4.378-fold and 7.369-fold increase in serum miR-129-5p expression in the DM (5.346 ± 0.405) and DMCs (8.998 ± 0.631) groups, respectively (P < 0.001), compared with the control group (1.221±0.090). In addition, the expression of serum miR-129-5p in patients with DMCs was higher than that in patients with DM, revealing a 1.683-fold increase (P < 0.001). Additionally, serum miR-129-5p expression significantly correlated with smoking history, disease duration, and glycated hemoglobin (HbA1c) in patients with DMCs (P < 0.001). The area under the ROC curve (AUC) of miR-129-5p as a serum marker was 0.964 (95% confidence interval [CI]: 0.930-0.997, P < 0.001) in distinguishing between patients with DM and healthy controls, whereas the AUC of miR-129-5p as a serum marker was 0.979 (95%CI: 0.959-0.999, P < 0.001) in distinguishing between patients with DMCs and healthy controls.

CONCLUSION

Elevated serum miR-129-5p expression levels correlate with the development of DMCs and can be utilized as a novel early diagnostic biomarker for DM combined with macrovascular complications.

The Diabetic Cardiomyopathy: The Contributing Pathophysiological Mechanisms

Individuals with diabetes mellitus (DM) disclose a higher incidence and a poorer prognosis of heart failure (HF) than non-diabetic people, even in the absence of other HF risk factors. The adverse impact of diabetes on HF likely reflects an underlying “diabetic cardiomyopathy” (DM–CMP), which may by exacerbated by left ventricular hypertrophy and coronary artery disease (CAD). The pathogenesis of DM-CMP has been a hot topic of research since its first description and is still under active investigation, as a complex interplay among multiple mechanisms may play a role at systemic, myocardial, and cellular/molecular levels. Among these, metabolic abnormalities such as lipotoxicity and glucotoxicity, mitochondrial damage and dysfunction, oxidative stress, abnormal calcium signaling, inflammation, epigenetic factors, and others. These disturbances predispose the diabetic heart to extracellular remodeling and hypertrophy, thus leading to left ventricular diastolic and systolic dysfunction. This Review aims to outline the major pathophysiological changes and the underlying mechanisms leading to myocardial remodeling and cardiac functional derangement in DM-CMP.

Identification of Circulating hsa_circ_0063425 and hsa_circ_0056891 as Novel Biomarkers for Detection of Type 2 Diabetes

CONTEXT

Circular RNAs (circRNAs), which are involved in the development of diseases by regulating gene expression, have become promising novel biomarkers for diseases.

OBJECTIVE

The aim of the present study was to identify the circulating circRNA biomarkers for early detection of type 2 diabetes (T2D).

METHODS

The circRNA expression profiles were screened by microarray and compared between 5 new T2D cases and 5 healthy controls. The expression of candidate circRNAs that may be involved in the insulin phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway were validated by RT-qPCR in a second sample with 30 T2D cases and 30 controls. The association between circRNAs and T2D and their clinical significances were further assessed by logistic regression model, correlation analysis, and ROC curve in a large cohort comprising 313 subjects. The microRNA (miRNA) targets of circRNAs were verified by dual-luciferase reporter assay and RNA immunoprecipitation assay.

RESULTS

Low expressed circ_0063425 and hsa_circ_0056891 were independent predictors of T2D, impaired fasting glucose (IFG), and insulin resistance. The 2-circRNA panel had a high diagnostic accuracy for discriminating T2D and IFG from healthy controls, especially when body mass index was integrated. miR-19a-3p and miR-1-3p were identified as the miRNA targets of hsa_circ_0063425 and hsa_circ_0056891, respectively. Significant positive correlations were found between the expression levels of AKT and hsa_circ_0063425, PI3K and hsa_circ_0056891, in the total sample and subgroups stratified by glucose levels.

CONCLUSION

Downregulated hsa_circ_0063425 and hsa_circ_0056891 might contribute to the pathogenesis of T2D. They are valuable circulating biomarkers for early detection of T2D, which may be involved in regulation of PI3K/AKT signaling.

Emerging roles of exosomal miRNAs in diabetes mellitus

Exosomes are small extracellular vesicles 40-160 nm in diameter that are secreted by almost all cell types. Exosomes can carry diverse cargo including RNA, DNA, lipids, proteins, and metabolites. Exosomes transfer substances and information between cells by circulating in body fluids and are thus involved in diverse physiological and pathological processes in the human body. Recent studies have closely associated exosomal microRNAs (miRNAs) with various human diseases, including diabetes mellitus (DM), which is a complex multifactorial metabolic disorder disease. Exosomal miRNAs are emerging as pivotal regulators in the progression of DM, mainly in terms of pancreatic β-cell injury and insulin resistance. Exosomal miRNAs are closely associated with DM-associated complications, such as diabetic retinopathy (DR), diabetic nephropathy (DN), and diabetic cardiomyopathy (DCM), etc. Further investigations of the mechanisms of action of exosomal miRNAs and their role in DM will be valuable for the thorough understanding of the physiopathological process of DM. Here, we have summarized recent findings regarding exosomal miRNAs associated with DM to provide a new strategy for identifying potential diagnostic biomarkers and drug targets for the early diagnosis and treatment, respectively, of DM.