MicroRNA and Diabetic Complications: A Clinical Perspective

Lessons and Applications of Omics Research in Diabetes Epidemiology

PURPOSE OF REVIEW

Recent advances in genomic technology and molecular techniques have greatly facilitated the identification of disease biomarkers, advanced understanding of pathogenesis of different common diseases, and heralded the dawn of precision medicine. Much of these advances in the area of diabetes have been made possible through deep phenotyping of epidemiological cohorts, and analysis of the different omics data in relation to detailed clinical information. In this review, we aim to provide an overview on how omics research could be incorporated into the design of current and future epidemiological studies.

RECENT FINDINGS

We provide an up-to-date review of the current understanding in the area of genetic, epigenetic, proteomic and metabolomic markers for diabetes and related outcomes, including polygenic risk scores. We have drawn on key examples from the literature, as well as our own experience of conducting omics research using the Hong Kong Diabetes Register and Hong Kong Diabetes Biobank, as well as other cohorts, to illustrate the potential of omics research in diabetes. Recent studies highlight the opportunity, as well as potential benefit, to incorporate molecular profiling in the design and set-up of diabetes epidemiology studies, which can also advance understanding on the heterogeneity of diabetes. Learnings from these examples should facilitate other researchers to consider incorporating research on omics technologies into their work to advance the field and our understanding of diabetes and its related co-morbidities. Insights from these studies would be important for future development of precision medicine in diabetes.

Inhibition of miR-543 alleviates cardiac fibroblast-to-myofibroblast transformation and collagen expression in insulin resistance via targeting PTEN

BACKGROUND

Myocardial interstitial fibrosis is an important manifestation of diabetic heart disease, and insulin resistance is one of the mechanisms of myocardial interstitial fibrosis. Some studies have found that miR-543 is associated with insulin resistance, but whether it plays a role in diabetic myocardial interstitial fibrosis remains unclear. This study aimed to investigate the role of miR-543 in diabetic myocardial interstitial fibrosis.

METHODS

The combination of high glucose and high insulin was used to establish an insulin-resistant myocardial fibroblast model. The expression levels of miR-543, α-SMA, collagen Ⅰ, collagen Ⅲ and PTEN were detected. Cell proliferation and migration were detected. Luciferase reporter gene assay was used to verify the targeting relationship between miR-543 and PTEN.

RESULTS

The expression of miR-543 was up-regulated in myocardial fibroblasts with insulin resistance, which was consistent with the results of bioinformatics analysis. The proliferation and migration levels of myocardial fibroblasts in insulin-resistant states were increased, and the expression levels of α-SMA, collagen Ⅰ and collagen Ⅲ were also increased. Inhibition of miR-543 expression could reverse the above changes. Target gene prediction and dual luciferase reporter assay demonstrated that miR-543 could bind to the 3'UTR region of PTEN. Moreover, the effect of miR-543 on insulin-resistant myocardial fibroblasts is mediated by targeting PTEN.

CONCLUSIONS

Inhibition of miR-543 can reduce myocardial fibroblast-myofibroblast transformation and collagen expression in insulin-resistant states by targeting PTEN.

DNA methylation markers for kidney function and progression of diabetic kidney disease

Epigenetic markers are potential biomarkers for diabetes and related complications. Using a prospective cohort from the Hong Kong Diabetes Register, we perform two independent epigenome-wide association studies to identify methylation markers associated with baseline estimated glomerular filtration rate (eGFR) and subsequent decline in kidney function (eGFR slope), respectively, in 1,271 type 2 diabetes subjects. Here we show 40 (30 previously unidentified) and eight (all previously unidentified) CpG sites individually reach epigenome-wide significance for baseline eGFR and eGFR slope, respectively. We also develop a multisite analysis method, which selects 64 and 37 CpG sites for baseline eGFR and eGFR slope, respectively. These models are validated in an independent cohort of Native Americans with type 2 diabetes. Our identified CpG sites are near genes enriched for functional roles in kidney diseases, and some show association with renal damage. This study highlights the potential of methylation markers in risk stratification of kidney disease among type 2 diabetes individuals.

Profile of crosstalk between glucose and lipid metabolic disturbance and diabetic cardiomyopathy: Inflammation and oxidative stress

In recent years, the risk, such as hypertension, obesity and diabetes mellitus, of cardiovascular diseases has been increasing explosively with the development of living conditions and the expansion of social psychological pressure. The disturbance of glucose and lipid metabolism contributes to both collapse of myocardial structure and cardiac dysfunction, which ultimately leads to diabetic cardiomyopathy. The pathogenesis of diabetic cardiomyopathy is multifactorial, including inflammatory cascade activation, oxidative/nitrative stress, and the following impaired Ca2+ handling induced by insulin resistance/hyperinsulinemia, hyperglycemia, hyperlipidemia in diabetes. Some key alterations of cellular signaling network, such as translocation of CD36 to sarcolemma, activation of NLRP3 inflammasome, up-regulation of AGE/RAGE system, and disequilibrium of micro-RNA, mediate diabetic oxidative stress/inflammation related myocardial remodeling and ventricular dysfunction in the context of glucose and lipid metabolic disturbance. Here, we summarized the detailed oxidative stress/inflammation network by which the abnormality of glucose and lipid metabolism facilitates diabetic cardiomyopathy.

Association of serum MicroRNA-145-5p levels with microvascular complications of type 1 Diabetes: The EURODIAB prospective complications study

AIMS

To investigate whether serum miR-145-5p levels were associated with micro-macrovascular chronic complications in patients with type 1 diabetes (DM1).

METHODS

A nested case-control study from the EURODIAB Prospective Complications Study was performed. Cases (n = 289) had one or more complications of diabetes, whereas controls (n = 153) did not have any complication. We measured miR-145-5p levels by qPCR and investigated the association with diabetes complications.

RESULTS

Mean miR-145-5p levels were significantly lower in cases with microangiopathy [2.12 (0.86-4.94)] compared to controls [3.15 (1.21-7.36), P < 0.05] even after adjustment for age, gender, and diabetes duration. In logistic regression analysis, miR-145-5p levels in the lowest tertile were associated with an over three-fold increased odds ratio (OR) of albuminuria [3.22 (1.17-8.81)], independently of both demographic and diabetes-related factors. In addition, mir145-5p levels in the lowest tertile were independently and inversely associated with arterial hypertension [1.96 (1.08-3.56)] and hypertension was the mediator of the relationship between miR-145-5p and albuminuria.

CONCLUSIONS

In this large cohort of DM1 patients, we found an inverse association between miR-145-5p and albuminuria that was mediated by systemic hypertension.

MiR-192 attenuates high glucose-induced pyroptosis in retinal pigment epithelial cells via inflammasome modulation

Diabetic retinopathy is one of the most characteristic complications of diabetes mellitus, and pyroptosis plays acrucial role in the onset and development of diabetic retinopathy. Although microRNA-192 (miR-192) has been demonstrated to be involved in diabetic retinopathy progression, to the best of our knowledge, its potential and mechanism in cell pyroptosis in diabetic retinopathy have not been studied. The present study demonstrated that high glucose (HG) contributes to the pyroptosis of retinal pigment epithelial (RPE) cells in a dose-dependent manner. The results revealed that miR-192 was weakly expressed in HG-induced RPE cells. Furthermore, overexpression of miR-192 abrogated the role of HG in RPE cell pyroptosis. Based on the bioinformatics analysis, a dual-luciferase reporter assay, and an RNA pull-down assay, FTO α-ketoglutarate-dependent dioxygenase (FTO) was demonstrated to be a direct target of miR-192. Additionally, upregulation of FTO abolished the effects of miR-192 on RPE cells treated with HG. Nucleotide-binding domain leucine-rich repeat family protein 3 (NLRP3) inflammasome activation is vital for cell pyroptosis, and FTO functions as a pivotal modulator in the N⁶-methyladenosine modifications of various genes. Mechanistically, FTO enhanced NLRP3 expression by facilitating demethylation of NLRP3. In conclusion, the present results demonstrate that miR-192 represses RPE cell pyroptosis triggered by HG via regulation of the FTO/NLRP3 signaling pathway.

Changes in microRNA expression profiles in diabetic cardiomyopathy rats following H3 relaxin treatment

ABSTRACT

MicroRNAs (miRNAs) are noncoding RNAs that play an important role in the mechanisms of diabetic cardiomyopathy (DCM); however, whether human recombinant relaxin-3 (H3 relaxin) inhibits myocardial injury in DCM rats and the underlying mechanisms involving miRNAs remain unknown. miRNA expression profiles were detected using miRNA microarray and bioinformatics analyses of myocardial tissues from control, DCM, and H3 relaxin-administered DCM groups, and the regulatory mechanisms of the miRNAs were investigated. A total of five miRNAs were downregulated in the myocardial tissues of DCM rats and upregulated in H3 relaxin-treated DCM rats, and one miRNA (miRNA let-7d-3p) was increased in the myocardial tissue of DCM rats, and decreased in H3 relaxin-treated DCM rats as revealed by miRNA microarray and validated by real-time PCR. Important signaling pathways were found to be triggered by the differentially expressed miRNAs, including metabolism, cancer, Rap1, PI3K-Akt, and MAPK signaling pathways. The study revealed that H3 relaxin improved glucose uptake in DCM rats, potentially via regulation of miRNA let-7d-3p.

MicroRNA-10 negatively regulates inflammation in diabetic kidney via targeting activation of the NLRP3 inflammasome

NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3) inflammasome activation has emerged as a central mediator of kidney inflammation in diabetic kidney disease (DKD). However, the mechanism underlying this activation in DKD remains poorly defined. In this study, we found that kidney-enriched microRNA-10a and -10b (miR-10a/b), predominantly expressed in podocytes and tubular epithelial cells, were downregulated in kidney from diabetic mice and patients with DKD. High glucose decreased miR-10a/b expression in vitro in an osmolarity-independent manner. miR-10a/b functioned as negative regulators of the NLRP3 inflammasome through targeting the 3'untranslated region of NLRP3 mRNA, inhibiting assembly of the NLRP3 inflammasome and decreasing caspase-1-dependent release of pro-inflammatory cytokines. Delivery of miR-10a/b into kidney prevented NLRP3 inflammasome activation and renal inflammation, and it reduced albuminuria in streptozotocin (STZ)-treated mice, whereas knocking down miR-10a/b increased NLRP3 inflammasome activation. Restoration of miR-10a/b expression in established DKD ameliorated kidney inflammation and mitigated albuminuria in both db/db and STZ-treated mice. These results suggest a novel intervention strategy for inhibiting kidney inflammation in DKD by targeting the NLRP3 inflammasome.

Epigenetic Remodeling in Obesity-Related Vascular Disease

Significance: The prevalence of obesity and cardiometabolic phenotypes is alarmingly increasing across the globe and is associated with atherosclerotic vascular complications and high mortality. In spite of multifactorial interventions, vascular residual risk remains high in this patient population, suggesting the need for breakthrough therapies. The mechanisms underpinning obesity-related vascular disease remain elusive and represent an intense area of investigation. Recent Advances: Epigenetic modifications-defined as environmentally induced chemical changes of DNA and histones that do not affect DNA sequence-are emerging as a potent modulator of gene transcription in the vasculature and might significantly contribute to the development of obesity-induced endothelial dysfunction. DNA methylation and histone post-translational modifications cooperate to build complex epigenetic signals, altering transcriptional networks that are implicated in redox homeostasis, mitochondrial function, vascular inflammation, and perivascular fat homeostasis in patients with cardiometabolic disturbances. Critical Issues: Deciphering the epigenetic landscape in the vasculature is extremely challenging due to the complexity of epigenetic signals and their function in regulating transcription. An overview of the most important epigenetic pathways is required to identify potential molecular targets to treat or prevent obesity-related endothelial dysfunction and atherosclerotic disease. This would enable the employment of precision medicine approaches in this setting. Future Directions: Current and future research efforts in this field entail a better definition of the vascular epigenome in obese patients as well as the unveiling of novel, cell-specific chromatin-modifying drugs that are able to erase specific epigenetic signals that are responsible for maladaptive transcriptional alterations and vascular dysfunction in obese patients. Antioxid. Redox Signal. 34, 1165-1199.

Parallel Multi-Omics in High-Risk Subjects for the Identification of Integrated Biomarker Signatures of Type 1 Diabetes

BACKGROUND

Biomarkers are crucial for detecting early type-1 diabetes (T1D) and preventing significant β-cell loss before the onset of clinical symptoms. Here, we present proof-of-concept studies to demonstrate the potential for identifying integrated biomarker signature(s) of T1D using parallel multi-omics.

METHODS

Blood from human subjects at high risk for T1D (and healthy controls; n = 4 + 4) was subjected to parallel unlabeled proteomics, metabolomics, lipidomics, and transcriptomics. The integrated dataset was analyzed using Ingenuity Pathway Analysis (IPA) software for disturbances in the at-risk subjects compared to controls.

RESULTS

The final quadra-omics dataset contained 2292 proteins, 328 miRNAs, 75 metabolites, and 41 lipids that were detected in all samples without exception. Disease/function enrichment analyses consistently indicated increased activation, proliferation, and migration of CD4 T-lymphocytes and macrophages. Integrated molecular network predictions highlighted central involvement and activation of NF-κB, TGF-β, VEGF, arachidonic acid, and arginase, and inhibition of miRNA Let-7a-5p. IPA-predicted candidate biomarkers were used to construct a putative integrated signature containing several miRNAs and metabolite/lipid features in the at-risk subjects.

CONCLUSIONS

Preliminary parallel quadra-omics provided a comprehensive picture of disturbances in high-risk T1D subjects and highlighted the potential for identifying associated integrated biomarker signatures. With further development and validation in larger cohorts, parallel multi-omics could ultimately facilitate the classification of T1D progressors from non-progressors.

Circulating microRNA-194 levels in Chinese patients with diabetic kidney disease: a case-control study

OBJECTIVE

MicroRNAs (miRNAs) regulate gene expression and are involved in diabetic kidney disease (DKD) pathogenesis. We investigated circulating miRNA-194 levels as a biomarker of DKD prevalence and incidence, and the relationship between miRNA-194 and CCAAT/enhancer binding protein (C/EBP) homologous protein (CHOP).

METHODS

We recruited 136 type-2 diabetes mellitus (T2DM) patients at the First People's Hospital of Lianyungang and 127 healthy individuals. Circulating miRNA-194 and CHOP levels were measured using quantitative reverse transcription qRT-PCR and enzyme-linked immunosorbent assay (ELISA), respectively. Anthropometric and biochemistry measurements were also made.

RESULTS

T2DM patients showed higher circulating miRNA-194 (p = 0.029) and lower circulating CHOP (p < 0.001) levels than controls. Circulating miRNA-194 levels were significantly higher in T2DM patients with a microalbumin/creatinine ratio (UmALB/Cr) ⩾ 300 mg/g (p < 0.001). In addition, there were significant intergroup differences in the circulating CHOP concentrations (p = 0.005). Bivariate analysis revealed that circulating miR-194 levels were negatively correlated with alpha-fetoprotein and CHOP levels (r = -0.222, -0.301; p = 0.018, 0.001, respectively), but positively correlated with fasting glucose, UmALB/Cr, Cr, Cystatin C, quantitative insulin check index (QUICKI) (r = 0.193, 0.446, 0.260, 0.339, and 0.250, respectively; p = 0.036, <0.001, 0.005, <0.001, and 0.006, respectively), particularly UmALB/Cr and Cystatin C (p < 0.001). Logistic regression analysis after adjusting for covariates associated with UmALB/Cr identified duration of T2DM, systolic blood pressure, Cr, estimated glomerular filtration rate, and waist circumference as independent factors associated with T2DM patients with UmALB/Cr > 300 (p = 0.030, 0.013, <0.001, <0.001, and 0.031, respectively).

CONCLUSION

Circulating miRNA-194 levels could be a novel biomarker for DKD.

miR-448-3p alleviates diabetic vascular dysfunction by inhibiting endothelial-mesenchymal transition through DPP-4 dysregulation

Diabetes mellitus (DM) often causes vascular endothelial damage and alters vascular microRNA (miR) expression. miR-448-3p has been reported to be involved in the development of DM, but whether miR-448-3p regulates diabetic vascular endothelial dysfunction remains unclear. To investigate the molecular mechanism of diabetic vascular endothelial dysfunction and the role of miR-448-3p therein, Sprague-Dawley rats were injected with streptozotocin (STZ) to establish diabetic animal model and the rat aortic endothelial cells were treated with high glucose to establish diabetic cell model. For the treatment group, after the induction of diabetes, the miR-448-3p levels in vivo and in vitro were upregulated by adeno-associated virus serotype 2 (AAV2)-miR-448-3p injection and miR-448-3p mimic transfection, respectively. Our results showed that AAV2-miR-448-3p injection alleviated the body weight loss and blood glucose level elevation induced by STZ injection. The miR-448-3p level was significantly decreased and the dipeptidyl peptidase-4 (DPP-4) messenger RNA level was increased in diabetic animal and cell models, which was reversed by miR-448-3p treatment. Moreover, the diabetic rats exhibited endothelial damage and endothelial-mesenchymal transition (EndMT), while AAV2-miR-448-3p injection relieved those situations. In vitro experiments demonstrated that miR-448-3p overexpression in endothelial cells alleviated endothelial damage by inhibiting EndMT through blocking the transforming growth factor-β/Smad pathway. We further proved that miR-448-3p negatively regulated DPP-4 by binding to its 3'-untranslated region, and DPP-4 overexpression reversed the effect of miR-448-3p overexpression on EndMT. Overall, we conclude that miR-448-3p overexpression inhibits EndMT via targeting DPP-4 and further ameliorates diabetic vascular endothelial dysfunction, indicating that miR-448-3p may serve as a promising therapeutic target for diabetic endothelial dysfunction.

Y RNAs: Biogenesis, Function and Implications for the Cardiovascular System

In recent years, progress in the field of high-throughput sequencing technology and its application to a wide variety of biological specimens has greatly advanced the discovery and cataloging of a diverse set of non-coding RNAs (ncRNAs) that have been found to have unexpected biological functions. Y RNAs are an emerging class of highly conserved, small ncRNAs. There is a growing number of reports in the literature demonstrating that Y RNAs and their fragments are not just random degradation products but are themselves bioactive molecules. This review will outline what is currently known about Y RNA including biogenesis, structure and functional roles. In addition, we will provide an overview of studies reporting the presence and functions attributed to Y RNAs in the cardiovascular system.

In silico transcriptional analysis of mRNA and miRNA reveals unique biosignatures that characterizes different types of diabetes

Diabetes (DM) has a significant impact on public health. We performed an in silico study of paired datasets of messenger RNA (mRNA) micro-RNA (miRNA) transcripts to delineate potential biosignatures that could distinguish prediabetes (pre-DM), type-1DM (T1DM) and type-2DM (T2DM). Two publicly available datasets containing expression values of mRNA and miRNA obtained from individuals diagnosed with pre-DM, T1DM or T2DM, and normoglycemic controls (NC), were analyzed using systems biology approaches to define combined signatures to distinguish different clinical groups. The mRNA profile of both pre-DM and T2DM was hallmarked by several differentially expressed genes (DEGs) compared to NC. Nevertheless, T1DM was characterized by an overall low number of DEGs. The miRNA signature profiles were composed of a substantially lower number of differentially expressed targets. Gene enrichment analysis revealed several inflammatory pathways in T2DM and fewer in pre-DM, but with shared findings such as Tuberculosis. The integration of mRNA and miRNA datasets improved the identification and discriminated the group composed by pre-DM and T2DM patients from that constituted by normoglycemic and T1DM individuals. The integrated transcriptomic analysis of mRNA and miRNA expression revealed a unique biosignature able to characterize different types of DM.

Circulating MicroRNA-15a Associates With Retinal Damage in Patients With Early Stage Type 2 Diabetes

Circulating microRNAs are potential biomarkers of type 2 diabetes mellitus (T2DM) and related complications. Here, we investigated the association of microRNA-15a with early retinal damage in T2DM. A cohort of untreated subjects screened for intermediate/high risk of T2DM, according to a score assessment questionnaire, and then recognized to have a normal (NGT) or impaired (IGT) glucose tolerance or T2DM was studied. The thickness of the ganglion cell complex (GCC), an early marker of retinal degeneration anteceding overt retinopathy was assessed by Optical Coherence Tomography. Total and extracellular vesicles (EV)-associated microRNA-15a quantity was measured in plasma by real time PCR. MicroRNA-15a level was significantly higher in subjects with IGT and T2DM compared with NGT. MicroRNA-15a abundance was correlated to body mass index and classical diabetes biomarkers, including fasting glucose, HbA1c, insulinemia, and HOMA-IR. Moreover, GCC thickness was significantly reduced in IGT and T2DM subjects compared with NGT controls. Importantly, total microRNA-15a correlated with GCC in IGT subjects, while in T2DM subjects, EV-microRNA-15a negatively correlated with GCC, suggesting that microRNA-15a may monitor initial retinal damage. The assessment of plasma microRNA-15a may help refining risk assessment and secondary prevention in patients with preclinical T2DM.

DNA nanotechnology approaches for microRNA detection and diagnosis

MicroRNAs are involved in the crucial processes of development and diseases and have emerged as a new class of biomarkers. The field of DNA nanotechnology has shown great promise in the creation of novel microRNA biosensors that have utility in lab-based biosensing and potential for disease diagnostics. In this Survey and Summary, we explore and review DNA nanotechnology approaches for microRNA detection, surveying the literature for microRNA detection in three main areas of DNA nanostructures: DNA tetrahedra, DNA origami, and DNA devices and motifs. We take a critical look at the reviewed approaches, advantages and disadvantages of these methods in general, and a critical comparison of specific approaches. We conclude with a brief outlook on the future of DNA nanotechnology in biosensing for microRNA and beyond.

Nicotinamide mononucleotide (NMN) supplementation promotes anti-aging miRNA expression profile in the aorta of aged mice, predicting epigenetic rejuvenation and anti-atherogenic effects

Understanding molecular mechanisms involved in vascular aging is essential to develop novel interventional strategies for treatment and prevention of age-related vascular pathologies. Recent studies provide critical evidence that vascular aging is characterized by NAD+ depletion. Importantly, in aged mice, restoration of cellular NAD+ levels by treatment with the NAD+ booster nicotinamide mononucleotide (NMN) exerts significant vasoprotective effects, improving endothelium-dependent vasodilation, attenuating oxidative stress, and rescuing age-related changes in gene expression. Strong experimental evidence shows that dysregulation of microRNAs (miRNAs) has a role in vascular aging. The present study was designed to test the hypothesis that age-related NAD+ depletion is causally linked to dysregulation of vascular miRNA expression. A corollary hypothesis is that functional vascular rejuvenation in NMN-treated aged mice is also associated with restoration of a youthful vascular miRNA expression profile. To test these hypotheses, aged (24-month-old) mice were treated with NMN for 2 weeks and miRNA signatures in the aortas were compared to those in aortas obtained from untreated young and aged control mice. We found that protective effects of NMN treatment on vascular function are associated with anti-aging changes in the miRNA expression profile in the aged mouse aorta. The predicted regulatory effects of NMN-induced differentially expressed miRNAs in aged vessels include anti-atherogenic effects and epigenetic rejuvenation. Future studies will uncover the mechanistic role of miRNA gene expression regulatory networks in the anti-aging effects of NAD+ booster treatments and determine the links between miRNAs regulated by NMN and sirtuin activators and miRNAs known to act in the conserved pathways of aging and major aging-related vascular diseases.

miRNA-181a over-expression in mesenchymal stem cell-derived exosomes influenced inflammatory response after myocardial ischemia-reperfusion injury

AIMS

The inflammation modulation effects of mesenchymal stromal cell-derived exosomes (MSC-EXO) are well established. We aimed to explore the mechanism behind the inflammatory responses of numerous exosomal cargo molecules that have been neglected in molecular biology research, and to develop an exosomal cargo delivery system that can exert a stronger therapeutic effect on myocardial ischemia-reperfusion (I/R) injury.

MAIN METHODS

Computational approaches were used to identify key exosomal miRNAs and their downstream mRNAs that are expressed in the inflammatory response. Direct interactions between miRNA-181a and the c-Fos mRNA complex were confirmed by luciferase reporter assay. MSC-EXO carrying miRNA-181a-overexpressing lentiviruses were intramyocardially injected into a mouse model of myocardial I/R injury. I/R progression was evaluated through echocardiography and immunofluorescence microscopy.

KEY FINDINGS

miRNA-181a provided substantial coverage against a host of immune-related genes through the miRNA-mRNA network. miRNA-181a delivery by MSC-EXO combined the immune-suppressing effect of miRNA-181a and the cell targeting capability of MSC-EXO to exert a stronger therapeutic effect on myocardium I/R injury.

SIGNIFICANCE

We showed the potential of MSC-EXO as a tool for the specific delivery of small RNAs in vivo. This study shed new light on the potential application of miRNA-181a-overexpressing MSC-EXO as a therapeutic strategy for myocardial I/R injury.

Can Epigenetics of Endothelial Dysfunction Represent the Key to Precision Medicine in Type 2 Diabetes Mellitus?

In both developing and industrialized Countries, the growing prevalence of Type 2 Diabetes Mellitus (T2DM) and the severity of its related complications make T2DM one of the most challenging metabolic diseases worldwide. The close relationship between genetic and environmental factors suggests that eating habits and unhealthy lifestyles may significantly affect metabolic pathways, resulting in dynamic modifications of chromatin-associated proteins and homeostatic transcriptional responses involved in the progression of T2DM. Epigenetic mechanisms may be implicated in the complex processes linking environmental factors to genetic predisposition to metabolic disturbances, leading to obesity and type 2 diabetes mellitus (T2DM). Endothelial dysfunction represents an earlier marker and an important player in the development of this disease. Dysregulation of the endothelial ability to produce and release vasoactive mediators is recognized as the initial feature of impaired vascular activity under obesity and other insulin resistance conditions and undoubtedly concurs to the accelerated progression of atherosclerotic lesions and overall cardiovascular risk in T2DM patients. This review aims to summarize the most current knowledge regarding the involvement of epigenetic changes associated with endothelial dysfunction in T2DM, in order to identify potential targets that might contribute to pursuing “precision medicine” in the context of diabetic illness.

Endothelial dysfunction in diabetes and hypertension: Role of microRNAs and long non-coding RNAs

The vascular endothelium acts as a barrier between the blood flow and the inner lining of the vessel wall, and it functions as a filtering machinery to filter out any unwanted transfer of materials from both sides (i.e. the blood and the surrounding tissues). It is evident that diseases such as diabetes, obesity, and hypertension disturb the normal endothelial functions in humans and lead to endothelial dysfunction, which may further precede to the development of atherosclerosis. Long non-coding RNAs and micro RNAs both are types of non-coding RNAs which, in the recent years, have increasingly been studied in the pathophysiology of many diseases including diabetes, obesity, cardiovascular diseases, neurological diseases, and others. Recent findings have pointed out important aspects on their relevance to endothelial function as well as dysfunction of the system which may arise from presence of diseases such as diabetes and hypertension. Diabetes or hypertension-mediated endothelial dysfunction show characteristics such as reduced nitric oxide synthesis through suppression of endothelial nitric oxide synthase activity in endothelial cells, reduced sensitivity of nitric oxide in smooth muscle cells, and inflammation - all of which have been either shown to be directly caused by gene regulatory mechanisms of non-coding RNAs or shown to be having a correlation with them. In this review, we aim to discuss such findings on the role of these non-coding RNAs in diabetes or hypertension-associated endothelial dysfunction and the related mechanisms that may pave the way for alleviating endothelial dysfunction and its related complications such as atherosclerosis.

Precision medicine in diabetes prevention, classification and management

Diabetes has become a major burden of healthcare expenditure. Diabetes management following a uniform treatment algorithm is often associated with progressive treatment failure and development of diabetic complications. Recent advances in our understanding of the genomic architecture of diabetes and its complications have provided the framework for development of precision medicine to personalize diabetes prevention and management. In the present review, we summarized recent advances in the understanding of the genetic basis of diabetes and its complications. From a clinician's perspective, we attempted to provide a balanced perspective on the utility of genomic medicine in the field of diabetes. Using genetic information to guide management of monogenic forms of diabetes represents the best-known examples of genomic medicine for diabetes. Although major strides have been made in genetic research for diabetes, its complications and pharmacogenetics, ongoing efforts are required to translate these findings into practice by incorporating genetic information into a risk prediction model for prioritization of treatment strategies, as well as using multi-omic analyses to discover novel drug targets with companion diagnostics. Further research is also required to ensure the appropriate use of this information to empower individuals and healthcare professionals to make personalized decisions for achieving the optimal outcome.

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.