Decreased expression of miR-150, miR146a and miR424 in type 1 diabetic patients: Association with ongoing islet autoimmunity

microRNAs in Type 1 Diabetes: Roles, Pathological Mechanisms, and Therapeutic Potential

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by the progressive destruction of pancreatic β-cells, leading to insulin deficiency. The primary drivers of β-cell destruction in T1D involve autoimmune-mediated processes that trigger chronic inflammation and ultimately β-cell loss. Regulatory microRNAs (miRNAs) play a crucial role in modulating these processes by regulating gene expression through post-transcriptional suppression of target mRNAs. Dysregulated miRNAs have been implicated in T1D pathogenesis, serving as both potential diagnostic biomarkers and therapeutic targets. This review explores the role of miRNAs in T1D, highlighting their involvement in disease mechanisms across both rodent models and human patients. While current antidiabetic therapies manage T1D symptoms, they do not prevent β-cell destruction, leaving patients reliant on lifelong insulin therapy. By summarizing key miRNA expression profiles in diabetic animal models and patients, this review explores the potential of miRNA-based therapies to restore β-cell function and halt or slow the progression of the disease.

Evaluation of miRNA-146a, miRNA-34a, and pro-inflammatory cytokines as a potential early indicators for type 1 diabetes mellitus

Background

Type I diabetes mellitus (T1DM) is one of the most common chronic autoimmune diseases worldwide. miRNAs are a class of small non-coding RNA molecules that have been linked to immune system functions, β-cell metabolism, proliferation, and death, all of which contribute to pathogenesis of TIDM. Dysregulated miRNAs have been identified in Egyptian TIDM patients.

Aim

Several miRNAs were profiled in Egyptian TIDM patients to determine whether they can be used as molecular biomarkers for T1DM. The relationship between the investigated miRNAs and pro-inflammatory cytokines (TNF-α and IL-6) has also been evaluated in the development of TIDM, in addition to the creation of a proposed model for TIDM prediction.

Patients & methods

Case-control study included 177 Egyptian patients with confirmed type I diabetes mellitus and 177 healthy individuals. MiRNA-34 and miRNA-146 were detected in serum samples using real-time PCR, whereas TNF-α and IL-6 levels were assessed using ELIZA.

Results

Patients with TIDM showed a significant decrease in the expression of miRNA-146, with a cut-off value ≤ 3.3, 48 % specificity, and 92.1 % sensitivity, whereas miRNA-34 had the highest sensitivity (95.5 %) and specificity (97.2 %) for differentiating diabetic patients from controls. Furthermore, other diagnostic proinflammatory markers showed lower sensitivity and specificity.

Conclusion

Serum levels of miRNA-34a, miRNA-146, IL-6, and TNF-α provide new insights into T1DM pathogenesis and could be used for screening and diagnosis purposes. They can be also a potential therapeutic target, as well as allowing for more strategies to improve T1DM disease outcomes.

A set of circulating microRNAs belonging to the 14q32 chromosome locus identifies two subgroups of individuals with recent-onset type 1 diabetes

Circulating microRNAs (miRNAs) are linked to the onset and progression of type 1 diabetes mellitus (T1DM), thus representing potential disease biomarkers. In this study, we employed a multiplatform sequencing approach to analyze circulating miRNAs in an extended cohort of prospectively evaluated recent-onset T1DM individuals from the INNODIA consortium. Our findings reveal that a set of miRNAs located within T1DM susceptibility chromosomal locus 14q32 distinguishes two subgroups of individuals. To validate our results, we conducted additional analyses on a second cohort of T1DM individuals, confirming the identification of these subgroups, which we have named cluster A and cluster B. Remarkably, cluster B T1DM individuals, who exhibit increased expression of a set of 14q32 miRNAs, show better glycemic control and display a different blood immunomics profile. Our findings suggest that this set of circulating miRNAs can identify two different T1DM subgroups with distinct blood immunomics at baseline and clinical outcomes during follow-up.

Clinical Variables Influence the Ability of miR-101, miR-150, and miR-21 to Predict Ventricular Remodeling after ST-Elevation Myocardial Infarction

Left ventricle remodeling (LVR) after acute myocardial infarction (MI) leads to impairment of both systolic and diastolic function, a significant contributor to heart failure (HF). Despite extensive research in the field, predicting post-MI LVR and HF is still a challenge. Several circulant microRNAs have been proposed as LVR predictors; however, their clinical value is controversial. Here, we used real-time quantitative PCR to quantify the plasma levels of hsa-miR-101, hsa-miR-150, and hsa-miR-21 on the first day of hospital admission of MI patients with ST-elevation (STEMI). We analyzed their correlation to the patient's clinical and paraclinical variables and evaluated their ability to discriminate between post-MI LVR and non-LVR. We show that, despite being excellent MI discriminators, none of these microRNAs can distinguish between LVR and non-LVR patients. Furthermore, we found that diabetes mellitus (DM), Hb level, and the number of erythrocytes significantly influence all three plasma microRNA levels. This suggests that plasma microRNAs' diagnostic and prognostic value in STEMI patients should be reevaluated and interpreted in the context of associated pathologies.

Text mining-based identification of promising miRNA biomarkers for diabetes mellitus

Introduction

MicroRNAs (miRNAs) are small, non-coding RNAs that play a critical role in diabetes development. While individual studies investigating the mechanisms of miRNA in diabetes provide valuable insights, their narrow focus limits their ability to provide a comprehensive understanding of miRNAs' role in diabetes pathogenesis and complications.

Methods

To reduce potential bias from individual studies, we employed a text mining-based approach to identify the role of miRNAs in diabetes and their potential as biomarker candidates. Abstracts of publications were tokenized, and biomedical terms were extracted for topic modeling. Four machine learning algorithms, including Naïve Bayes, Decision Tree, Random Forest, and Support Vector Machines (SVM), were employed for diabetes classification. Feature importance was assessed to construct miRNA-diabetes networks.

Results

Our analysis identified 13 distinct topics of miRNA studies in the context of diabetes, and miRNAs exhibited a topic-specific pattern. SVM achieved a promising prediction for diabetes with an accuracy score greater than 60%. Notably, miR-146 emerged as one of the critical biomarkers for diabetes prediction, targeting multiple genes and signal pathways implicated in diabetic inflammation and neuropathy.

Conclusion

This comprehensive approach yields generalizable insights into the network miRNAs-diabetes network and supports miRNAs' potential as a biomarker for diabetes.

Association of MicroRNA-146a with Type 1 and 2 Diabetes and their Related Complications

Most medical investigations have found a reduced blood level of miR-146a in type 2 diabetes (T2D) patients, suggesting an important role for miR-146a (microRNA-146a) in the etiology of diabetes mellitus (DM) and its consequences. Furthermore, injection of miR-146a mimic has been confirmed to alleviate diabetes mellitus in diabetic animal models. In this line, deregulation of miR-146a expression has been linked to the progression of nephropathy, neuropathy, wound healing, olfactory dysfunction, cardiovascular disorders, and retinopathy in diabetic patients. In this review, besides a comprehensive review of the function of miR-146a in DM, we discussed new findings on type 1 (T1MD) and type 2 (T2DM) diabetes mellitus, highlighting the discrepancies between clinical and preclinical investigations and elucidating the biological pathways regulated through miR-146a in DM-affected tissues.

Multiple functions and regulatory network of miR-150 in B lymphocyte-related diseases

MicroRNAs (miRNAs) play vital roles in the post-transcriptional regulation of gene expression. Previous studies have shown that miR-150 is a crucial regulator of B cell proliferation, differentiation, metabolism, and apoptosis. miR-150 regulates the immune homeostasis during the development of obesity and is aberrantly expressed in multiple B-cell-related malignant tumors. Additionally, the altered expression of MIR-150 is a diagnostic biomarker of various autoimmune diseases. Furthermore, exosome-derived miR-150 is considered as prognostic tool in B cell lymphoma, autoimmune diseases and immune-mediated disorders, suggesting miR-150 plays a vital role in disease onset and progression. In this review, we summarized the miR-150-dependent regulation of B cell function in B cell-related immune diseases.

MicroRNA-150 (miR-150) and Diabetic Retinopathy: Is miR-150 Only a Biomarker or Does It Contribute to Disease Progression?

Diabetic retinopathy (DR) is a chronic disease associated with diabetes mellitus and is a leading cause of visual impairment among the working population in the US. Clinically, DR has been diagnosed and treated as a vascular complication, but it adversely impacts both neural retina and retinal vasculature. Degeneration of retinal neurons and microvasculature manifests in the diabetic retina and early stages of DR. Retinal photoreceptors undergo apoptosis shortly after the onset of diabetes, which contributes to the retinal dysfunction and microvascular complications leading to vision impairment. Chronic inflammation is a hallmark of diabetes and a contributor to cell apoptosis, and retinal photoreceptors are a major source of intraocular inflammation that contributes to vascular abnormalities in diabetes. As the levels of microRNAs (miRs) are changed in the plasma and vitreous of diabetic patients, miRs have been suggested as biomarkers to determine the progression of diabetic ocular diseases, including DR. However, few miRs have been thoroughly investigated as contributors to the pathogenesis of DR. Among these miRs, miR-150 is downregulated in diabetic patients and is an endogenous suppressor of inflammation, apoptosis, and pathological angiogenesis. In this review, how miR-150 and its downstream targets contribute to diabetes-associated retinal degeneration and pathological angiogenesis in DR are discussed. Currently, there is no effective treatment to stop or reverse diabetes-caused neural and vascular degeneration in the retina. Understanding the molecular mechanism of the pathogenesis of DR may shed light for the future development of more effective treatments for DR and other diabetes-associated ocular diseases.

MicroRNAs and Diabetes Mellitus Type 1

Type 1 diabetes mellitus is a multifactorial, progressive, autoimmune disease with a strong genetic feature that can affect multiple organs, including the kidney, eyes, and nerves. Early detection of type 1 diabetes can help critically to avoid serious damages to these organs. MicroRNAs are small RNA molecules that act in post-transcriptional gene regulation by attaching to the complementary sequence in the 3'-untranslated region of their target genes. Alterations in the expression of microRNA coding genes are extensively reported in several diseases, such as type 1 diabetes. Presenting non-invasive biomarkers for early detection of type 1 diabetes by quantifying microRNAs gene expression level can be a significant step in biotechnology and medicine. This review discusses the area of microRNAs dysregulation in type 1 diabetes and affected molecular mechanisms involved in pancreatic islet cell formation and dysregulation in the expression of inflammatory elements as well as pro-inflammatory cytokines.

Circulating microRNAs are associated with variability in fasting blood glucose over 12-months and target pathways related to type 2 diabetes: A pilot study

INTRODUCTION

MicroRNAs (miRs) may be important regulators of risk for type 2 diabetes (T2D). Circulating miRs may provide information about which individuals are at risk for T2D. The purpose of this study was to assess longitudinal associations between circulating miR expression and variability in fasting blood glucose (FBG) and to identify miR-targeted genes and biological pathways.

METHODS

Variability in FBG was estimated using standard deviation from participants (n = 20) in a previously completed yoga trial. Expression of 402 miRs was measured using hydrogel particle lithography. MirTarBase was used to identify mRNAs, and miRPathDB was used to identify pathways targeted by differentially expressed miRs.

RESULTS

Six circulating miRs (miR-192, miR-197, miR-206, miR-424, miR-486, and miR-93) were associated with variability in FBG and targeted 143 genes and 23 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Six mRNAs (AKT1, CCND1, ESR1, FASN, SMAD7, and VEGFA) were targeted by at least two miRs and four of those were located in miR-targeted KEGG pathways.

CONCLUSIONS

Circulating miRs are associated with variability in FBG in individuals at risk for T2D. Further studies are needed to determine whether miRs may be prodromal biomarkers that can identify which individuals are at greatest risk to progress to T2D and which biological pathways underlie this risk.

MicroRNA-150 and its target ETS-domain transcription factor 1 contribute to inflammation in diabetic photoreceptors

Obesity‐associated type 2 diabetes (T2D) is on the rise in the United States due to the obesity epidemic, and 60% of T2D patients develop diabetic retinopathy (DR) in their lifetime. Chronic inflammation is a hallmark of obesity and T2D and a well‐accepted major contributor to DR, and retinal photoreceptors are a major source of intraocular inflammation and directly contribute to vascular abnormalities in diabetes. However, how diabetic insults cause photoreceptor inflammation is not well known. In this study, we used a high‐fat diet (HFD)‐induced T2D mouse model and cultured photoreceptors treated with palmitic acid (PA) to decipher major players that mediate high‐fat‐induced photoreceptor inflammation. We found that PA‐elicited microRNA‐150 (miR‐150) decreases with a consistent upregulation of ETS‐domain transcription factor 1 (Elk1), a downstream target of miR‐150, in PA‐elicited photoreceptor inflammation. We compared wild‐type (WT) and miR‐150 null (miR‐150^−/−) mice fed with an HFD and found that deletion of miR‐150 exacerbated HFD‐induced photoreceptor inflammation in conjunction with upregulated ELK1. We further delineated the critical cellular localization of phosphorylated ELK1 at serine 383 (pELK1_S383) and found that decreased miR‐150 exacerbated the T2D‐induced inflammation in photoreceptors by upregulating ELK1 and pELK1_S383, and knockdown of ELK1 alleviated PA‐elicited photoreceptor inflammation.

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.

The complex functions of microRNA-150 in allergy, autoimmunity and immune tolerance

<abstract> <p>At present, special efforts are being made to develop the strategies allowing for activation of long-lasting antigen-specific immune tolerance in therapy of allergic and autoimmune diseases. Some of these therapeutic approaches are aimed at modulating cell functions at genetic level by using miRNA-based and miRNA-targeting treatments. Simultaneously, the crucial role of extracellular vesicles as natural miRNA conveyors is highlighted for induction of antigen-specific immune tolerance, especially that they appear to be easily manipulatable for therapeutic applications. Among other immune-related miRNAs, miR-150 is getting special attention as it is differently expressed by immune cells at various stages of their maturation and differentiation. In addition, miR-150 is involved in different signaling cascades orchestrating humoral and cell-mediated mechanisms of both innate and adaptive immune responses. Therefore, miR-150 is considered a master regulator of immunity in mammals. Currently, physiological miR-150-dependent regulatory circuits and causes of their malfunctioning that underlie the pathogenesis of allergic and autoimmune disorders are being unraveled. Thus, present review summarizes the current knowledge of the role of miR-150 in the pathogenesis and complications of these diseases. Furthermore, the involvement of miR-150 in regulation of immune responses to allergens and self-antigens and in induction of antigen-specific immune tolerance is discussed with the special emphasis on the therapeutic potential of this miRNA.</p> </abstract>

microRNA-143-3p contributes to inflammatory reactions by targeting FOSL2 in PBMCs from patients with autoimmune diabetes mellitus

AIM

Autoimmune diabetes mellitus (defined as ADM) comprises classical type 1 diabetes mellitus (T1DM) and latent autoimmune diabetes in adults (LADA). In this study, microRNAs (miRNAs) expression profiles and functions in peripheral blood mononuclear cells (PBMCs) of ADM patients were mapped and used to explore epigenetic regulation of the pathogenesis of ADM.

METHODS

PBMCs samples from T1DM patients, LADA patients, and type 2 diabetes mellitus (T2DM) patients, as well as age- and sex-matched healthy controls for T1DM and T2DM, respectively, were collected and were sequenced to screen the miRNAs expression profiles. The target genes were verified by dual-luciferase reporter assay. Silencing or overexpressing of the differentially expressed miRNAs, or simultaneously silencing the miRNAs and it's target gene, and then levels of the mRNAs, protein and cytokines were detected.

RESULTS

miR-143-3p expression was upregulated in ADM patients. The target gene of miR-143-3p was identified as Fos-related antigen 2 (FOSL2). Transfection of a miR-143-3p inhibitor into PBMCs upregulated FOSL2 expression, resulting in a downregulated expression of the IL-2, TNF-α, and IFN-γ, and an upregulated expression of IL-6. Transfection of a miR-143-3p mimic into PBMCs downregulated FOSL2 expression, leading to an upregulation of IL-2 and TNF-α expression and a downregulation of IL-6 expression. When silencing FOSL2 while inhibiting miR-143-3p in PBMCs, there was no significant change in expression of the FOSL2 mRNA, protein and cytokines.

CONCLUSION

The expression of miR-143-3p in PBMCs from ADM patients is upregulated. miR-143-3p could function in the pathogenesis of ADM by modulating the inflammatory reaction through FOSL2.

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSION

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

Reading between the (Genetic) Lines: How Epigenetics is Unlocking Novel Therapies for Type 1 Diabetes

Type 1 diabetes (T1D) is an autoimmune condition where the body’s immune cells destroy their insulin-producing pancreatic beta cells leading to dysregulated glycaemia. Individuals with T1D control their blood glucose through exogenous insulin replacement therapy, often using multiple daily injections or pumps. However, failure to accurately mimic intrinsic glucose regulation results in glucose fluctuations and long-term complications impacting key organs such as the heart, kidneys, and/or the eyes. It is well established that genetic and environmental factors contribute to the initiation and progression of T1D, but recent studies show that epigenetic modifications are also important. Here, we discuss key epigenetic modifications associated with T1D pathogenesis and discuss how recent research is finding ways to harness epigenetic mechanisms to prevent, reverse, or manage T1D.

Histone Deacetylase 3 Aggravates Type 1 Diabetes Mellitus by Inhibiting Lymphocyte Apoptosis Through the microRNA-296-5p/Bcl-xl Axis

Type 1 diabetes mellitus (T1DM) is a chronic autoimmune disease characterized by immune-mediated destruction of pancreatic beta-cells. Multiple microRNAs (miRNAs) have been implicated in T1DM pathogenesis. Although histone deacetylase 3 (HDAC3) has been reported to be involved in T1DM, the underlying mechanisms remain to be further elucidated. This study was designed to investigate the potential regulatory role of Hdac3 on T1DM progression. The expression of miR-296-5p and B-cell leukemia-XL (BCL-XL) was determined using RT-qPCR and Western blot assay in peripheral blood mononuclear cells (PBMCs) of patients with T1DM, tumor necrosis factor-α (TNF-α)- and cycloheximide (CHX)-induced cell model, and streptozotocin (STZ)-induced rat model. The binding affinity between miR-296-5p and Bcl-xl was verified by using dual-luciferase reporter gene assay, and the binding between Hdac3 and the promoter region of miR-296-5p was validated using chromatin immunoprecipitation assay. Western blot analysis and flow cytometry were conducted to assess the apoptotic events of lymphocytes. miR-296-5p expression was downregulated while BCL-XL expression was upregulated in PBMCs of patients with T1DM. An adverse correlation was identified between miR-296-5p and Bcl-xl in mouse TE15 B lymphocytes. Bcl-xl was further validated to be targeted and negatively regulated by miR-296-5p in 293 T cells. Hdac3 inhibited miR-296-5p expression by binding to its promoter region. The effects of overexpressed Hdac3 on lymphocyte apoptosis was counterweighed via downregulation of Bcl-xl or upregulation of miR-296-5p, the mechanism of which was further validated in a rat model of DM. Taken together, the Hdac3-mediated upregulation of Bcl-xl via inhibiting miR-296-5p promoter activity enhanced the anti-apoptotic capacity of lymphocytes to accelerate the occurrence of T1DM.

RETRACTED: NF-κB inhibits the occurrence of type 1 diabetes through microRNA-150-dependent PUMA degradation

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy) This article has been retracted at the request of the Editor-in-Chief. Concern was raised about the reliability of the Western blot results in Figures 1D,E+H, 2E+H, 3F,H+K, and 4B+E which appear to have a similar phenotype as many other publications, as detailed here: https://pubpeer.com/publications/C6FD5C041268DBBCDA521AEC112FA4 and here: https://docs.google.com/spreadsheets/d/1r0MyIYpagBc58BRF9c3luWNlCX8VUvUuPyYYXzxWvgY/edit#gid=262337249. The journal requested the corresponding author comment on these concerns and provide the raw Western blot data. However, the authors were not able to satisfactorily fulfill this request and therefore the Editor-in-Chief decided to retract the article.

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

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

Emerging roles of non-coding RNAs in the pathogenesis of type 1 diabetes mellitus

Type 1 diabetes mellitus (T1D) is a lifelong autoimmune disorder that is increasingly prevalent in populations worldwide. As well as affecting adults, T1D is one of the most prevalent chronic childhood disorders. Several lines of evidence point to dysregulation of both cellular and humoral immune responses in this disorder. Several genetic loci have been associated with risk of T1D, implying the presence of a complex multifactorial pattern of inheritance for this disorder. Moreover, recent studies have reported dysregulation of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) in animal models of T1D or clinical samples. Several immune-related molecules and pathways such as NF-κB, PI3K/Akt/FOXO, JAK, MAPK, mTOR and STAT pathways are regulated by non-coding RNAs in the context of T1D. Improved understanding of the role of lncRNAs and miRNAs in the pathogenesis of T1D would facilitate design of preventive therapeutic modalities. In the current review, we summarize the results of animal and human studies that report dysregulation of these transcripts and their function in T1D.

Approaches to inducing antigen-specific immune tolerance in allergy and autoimmunity: Focus on antigen-presenting cells and extracellular vesicles

Increasing prevalence of allergic and autoimmune diseases urges clinicians and researchers to search for new and efficient treatments. Strategies that activate antigen-specific immune tolerance and simultaneously maintain immune reactivity to all other antigens deserve special attention. Accordingly, antigen-presenting cells (APCs) seem to be the best suited for orchestrating these mechanisms by directing T cell immune responses towards a tolerant subtype. Recent advances in understanding cell-to-cell communication via extracellular vesicles (EVs) make the latter promising candidates for reprogramming APCs towards a tolerant phenotype, and for mediating tolerogenic APC function. Thus, comprehensive studies have been undertaken to describe the interactions of APCs and EVs naturally occurring during immune tolerance induction, as well as to develop EV-based manoeuvres enabling the induction of immune tolerance in an antigen-specific manner. In this review, we summarize the findings of relevant studies, with a special emphasis on future perspectives on their translation to clinical practice.

Molecular biomarkers in diabetes mellitus (DM)

Background: Diabetes mellitus (DM) is a growing epidemic metabolic syndrome, which affects near 5.6% of the world's population. Almost 12% of health expenditure is dedicated to this disorder. Discovering and developing biomarkers as a practical guideline with high specificity and sensitivity for the diagnosis, prognosis, and clinical management of DM is one of the subjects of great interest among DM researchers due to the long-lasting asymptomatic clinical manifestation of DM. In this study, we described a recently identified molecular biomarker involved in DM. Methods: This review study was done at the Diabetes Research Center affiliated to Shahid Sadoughi University of Medical Sciences. PubMed, Scopus, Google Scholar, and Web of Science were searched using the following keywords: "diabetes mellitus", "biomarker", "microRNA", "diagnostic tool" and "clinical manifestation." Results: A total of 107 studies were finally included in this review. After evaluating numerous articles, including original, metaanalysis, and review studies, we focused on molecular biomarkers involved in DM diagnosis and management. Conclusion: Increasing interest in biomarkers associated with DM goes back to its role in decreasing diabetes-related morbidity and mortality. This review focused on major molecular biomarkers such as proteomic and microRNA (miRNAs) as novel and interesting DM biomarkers that can help achieve timely diagnosis of DM.

Low Circulating Levels of miR-451a in Girls with Polycystic Ovary Syndrome: Different Effects of Randomized Treatments

CONTEXT

Polycystic ovary syndrome (PCOS) is a prevalent disorder in adolescent girls, purportedly driven by hepato-visceral fat excess, and often followed by subfertility and type 2 diabetes.

OBJECTIVE

We studied the baseline microRNA (miRNA) profile of girls with PCOS, and the effects of a randomized treatment with an oral contraceptive (OC) or with spironolactone-pioglitazone-metformin (SPIOMET, aiming at loss of hepato-visceral fat excess) for 1 year.

DESIGN & PATIENTS

The miRNA profile was assessed by RNA sequencing in girls with PCOS who had participated in a randomized, open-label, single-center, pilot study (n = 31; age 15.7 years, body mass index (BMI) 23.1 kg/m2). Healthy age- and BMI-matched girls (n = 13) served as controls. Differentially expressed miRNAs were validated by RT-qPCR in the entire study population. Post-treatment ovulation rates were assessed by salivary progesterone in PCOS girls.

SETTING

Endocrinology Department, University Hospital.

RESULTS

Girls with PCOS, compared with controls, had markedly reduced concentrations of circulating miR-451a, miR-652-3p, miR-106b-5p, and miR-206; pathway enrichment analysis showed that these miRNAs target genes involved in energy homeostasis and cell cycle control. In the present study, miR-451a could diagnose PCOS with 100% sensitivity and 100% specificity. SPIOMET (but not OC) was accompanied by on-treatment normalization of the miRNA profile in girls with PCOS; miR-451a concentrations after 1 year on OC or SPIOMET treatment associated closely (r = 0.66; P < .0001) with post-treatment ovulation rates.

CONCLUSION

SPIOMET treatment for 1 year normalizes the miRNA profile of girls with PCOS. Circulating miR-451a may become a biomarker to guide the diagnosis and treatment of PCOS in adolescence.

MicroRNA-150 serves as a diagnostic biomarker and is involved in the inflammatory pathogenesis of Parkinson's disease

Background

Dysregulation of microRNAs (miRNAs) has been reported to be involved in the neuroinflammatory pathogenesis of PD. This study aimed to investigate the serum expression of microRNA‐150 (miR‐150) in Parkinson's disease (PD) patients and further uncover the regulatory effect of miR‐150 on neuroinflammation.

Methods

Quantitative Real‐Time PCR was used to measure the expression of miR‐150. A receiver operating characteristic curve was applied to evaluate the diagnostic value of miR‐150. The effect of miR‐150 on neuroinflammation was analyzed by examining its correlation with proinflammatory cytokines and gain‐of‐function experiments in microglia treated with LPS.

Results

Serum miR‐150 expression was downregulated in PD patients compared with the healthy controls, and served as a candidate diagnostic biomarker for the screening of PD cases. Negative correlation was found between miR‐150 levels and the levels of procytokines in PD patients. By the treatment of LPS, microglia BV2 cells had a reduced expression of miR‐150, and the enhanced neuroinflammatory responses were inhibited by the overexpression of miR‐150. AKT3 was verified as a target of miR‐150 in BV2 cells.

Conclusion

All the data of this study revealed that the decreased serum miR‐150 serves as a potential diagnostic biomarker. The methods to increase miR‐150 expression may have a beneficial effect in PD via suppressing the neuroinflammation by targeting AKT3.

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.

Nucleic acid-based theranostics in type 1 diabetes

Application of RNAi interference for type 1 diabetes (T1D) therapy bears tremendous potential. This review will discuss vehicles for oligonucleotide delivery, imaging modalities used for delivery monitoring, therapeutic targets, and different theranostic strategies that can be applied for T1D treatment.

MicroRNA Post-transcriptional Regulation of the NLRP3 Inflammasome in Immunopathologies

Inflammation has a crucial role in protection against various pathogens. The inflammasome is an intracellular multiprotein signaling complex that is linked to pathogen sensing and initiation of the inflammatory response in physiological and pathological conditions. The most characterized inflammasome is the NLRP3 inflammasome, which is a known sensor of cell stress and is tightly regulated in resting cells. However, altered regulation of the NLRP3 inflammasome is found in several pathological conditions, including autoimmune disease and cancer. NLRP3 expression was shown to be post-transcriptionally regulated and multiple miRNA have been implicated in post-transcriptional regulation of the inflammasome. Therefore, in recent years, miRNA based post-transcriptional control of NLRP3 has become a focus of much research, especially as a potential therapeutic approach. In this review, we provide a summary of the recent investigations on the role of miRNA in the post-transcriptional control of the NLRP3 inflammasome, a key regulator of pro-inflammatory IL-1β and IL-18 cytokine production. Current approaches to targeting the inflammasome product were shown to be an effective treatment for diseases linked to NLRP3 overexpression. Although utilizing NLRP3 targeting miRNAs was shown to be a successful therapeutic approach in several animal models, their therapeutic application in patients remains to be determined.

H19X-encoded miR-424(322)/-503 cluster: emerging roles in cell differentiation, proliferation, plasticity and metabolism

miR-424(322)/-503 are mammal-specific members of the extended miR-15/107 microRNA family. They form a co-expression network with the imprinted lncRNA H19 in tetrapods. miR-424(322)/-503 regulate fundamental cellular processes including cell cycle, epithelial-to-mesenchymal transition, hypoxia and other stress response. They control tissue differentiation (cardiomyocyte, skeletal muscle, monocyte) and remodeling (mammary gland involution), and paradoxically participate in tumor initiation and progression. Expression of miR-424(322)/-503 is governed by unique mechanisms involving sex hormones. Here, we summarize current literature and provide a primer for future endeavors.

Decreased Serum microRNA-21, microRNA-25, microRNA-146a, and microRNA-181a in Autoimmune Diabetes: Potential Biomarkers for Diagnosis and Possible Involvement in Pathogenesis

OBJECTIVE

Previous studies have revealed dysregulated circulating microRNAs (miRNAs) in patients with type 1 diabetes (T1D). Here, we explored the serum levels of miR-21, miR-25, miR-146a, and miR-181a in patients with autoimmune diabetes (T1D and latent autoimmune diabetes of adults (LADA)) compared with type 2 diabetes (T2D) and nondiabetic individuals.

DESIGN PATIENTS AND MEASUREMENTS

The serum levels of miR-21, miR-25, miR-146a, and miR-181a in patients with T1D (n = 29), LADA (n = 16), and T2D (n = 31) and in nondiabetic individuals (n = 19) were determined by quantitative real-time polymerase chain reaction, and receiver-operating characteristic (ROC) curves were evaluated to determine the discriminatory performances of these four miRNAs. Furthermore, target genes and pathways potentially modulated by these four miRNAs were predicted by bioinformatics analysis to investigate the possible functions of these miRNAs in autoimmune diabetes. Subsequently, multiple logistic regression analysis was performed to identify independent predictors for autoimmune diabetes, and a nomogram was established.

RESULTS

miR-21, miR-25, miR-146a, and miR-181a were significantly downregulated in the serum of patients with autoimmune diabetes compared with those in T2D patients and nondiabetic individuals (p < 0.001). The areas under the ROC curves of these four miRNAs were greater than 0.80 (p < 0.001). Bioinformatics analysis suggested that miR-21, miR-25, miR-146a, and miR-181a regulated multiple genes in pathways associated with immunity, inflammatory responses, hyperglycemia, and metabolism, which are involved in the pathogenesis of autoimmune diabetes. Multiple logistic regression analysis identified miR-25 (odds ratio (OR): 0.001, p < 0.05), miR-146a (OR: 0.136, p < 0.05), and fasting C-peptide levels (OR: 0.064, p < 0.05) as independent predictors of autoimmune diabetes.

CONCLUSIONS

miR-25 and miR-146a may serve as potential circulating biomarkers and provide insights into the pathogenesis of autoimmune diabetes.

Epigenetics Variation and Pathogenesis in Diabetes

PURPOSE OF REVIEW

Great strides have recently been made in elucidating the role of genetic sequence variation in diabetes pathogenesis. Increasingly, studies are focusing on other factors that may contribute to the pathogenesis of diabetes, such as epigenetics, a term "traditionally" encompassing changes to the DNA that do not alter sequence and are heritable (primary methylation and histone modification) but often expanded to include microRNAs. This review summarizes latest findings on the role of epigenetics in diabetes pathogenesis.

RECENT FINDINGS

Recent studies illustrate roles for methylation changes, histone modification, imprinting, and microRNAs across several diabetes types and complications. Notably, methylation changes in the human leukocyte antigen (HLA) region have been found to precede the development of type 1 diabetes. In type 2 diabetes, lifestyle factors appear to interact with epigenetic mechanisms in pathogenesis. Emerging technologies have allowed increasingly comprehensive descriptive analysis of the role of epigenetic mechanisms in diabetes pathogenesis which have yielded meaningful insights into effects on expression of relevant genes. These findings have the potential to inform future development of predictive testing to enable primary prevention and further work to uncover the complex pathogenesis of diabetes.

The MicroRNA-326: Autoimmune diseases, diagnostic biomarker, and therapeutic target

MicroRNAs (miRNAs) are uniquely regulated in healthy, inflamed, activated, cancerous, or other cells and tissues of a pathological state. Many studies confirm that immune dysregulation and autoimmune diseases with inflammation are correlated with various miRNA expression changes in targeted tissues and cells in innate or adaptive immunity. In this review, we will explain the history and classification of epigenetic changes. Next, we will describe the role of miRNAs changes, especially mir-326 in autoimmunity, autoinflammatory, and other pathological conditions. A systematic search of MEDLINE, Embase, and Cochrane Library was presented for all related studies from 1899 to 2017 with restrictions in the English language. In recent years, researchers have concentrated on mostly those roles of miRNA that are correlated with the inflammatory and anti-inflammatory process. Latest studies have proposed a fundamental pathogenic role in cancers and autoinflammatory diseases. Studies have described the role of microRNAs in autoimmunity and autoinflammatory diseases, cancers, and so on. The miRNA-326 expression plays a significant role in autoimmune and other types of diseases.

MicroRNA expression profiles and type 1 diabetes mellitus: systematic review and bioinformatic analysis

Growing evidence indicates that microRNAs (miRNAs) have a key role in processes involved in type 1 diabetes mellitus (T1DM) pathogenesis, including immune system functions and beta-cell metabolism and death. Although dysregulated miRNA profiles have been identified in T1DM patients, results are inconclusive; with only few miRNAs being consistently dysregulated among studies. Thus, we performed a systematic review of the literature on the subject, followed by bioinformatic analysis, to point out which miRNAs are dysregulated in T1DM-related tissues and in which pathways they act. PubMed and EMBASE were searched to identify all studies that compared miRNA expressions between T1DM patients and non-diabetic controls. Search was completed in August, 2017. Those miRNAs consistently dysregulated in T1DM-related tissues were submitted to bioinformatic analysis, using six databases of miRNA-target gene interactions to retrieve their putative targets and identify potentially affected pathways under their regulation. Thirty-three studies were included in the systematic review: 19 of them reported miRNA expressions in human samples, 13 in murine models and one in both human and murine samples. Among 278 dysregulated miRNAs reported in these studies, 25.9% were reported in at least 2 studies; however, only 48 of them were analyzed in tissues directly related to T1DM pathogenesis (serum/plasma, pancreas and peripheral blood mononuclear cells (PBMCs)). Regarding circulating miRNAs, 11 were consistently dysregulated in T1DM patients compared to controls: miR-21-5p, miR-24-3p, miR-100-5p, miR-146a-5p, miR-148a-3p, miR-150-5p, miR-181a-5p, miR-210-5p, miR-342-3p, miR-375 and miR-1275. The bioinformatic analysis retrieved a total of 5867 validated and 2979 predicted miRNA-target interactions for human miRNAs. In functional enrichment analysis of miRNA target genes, 77 KEGG terms were enriched for more than one miRNA. These miRNAs are involved in pathways related to immune system function, cell survival, cell proliferation and insulin biosynthesis and secretion. In conclusion, eleven circulating miRNAs seem to be dysregulated in T1DM patients in different studies, being potential circulating biomarkers of this disease.