The microRNA-29 family - role in metabolism and metabolic disease

Effects of miR-29c on proliferation and adipogenic differentiation of porcine bone marrow mesenchymal stromal cells

microRNAs (miRNAs), a subclass of noncoding short RNAs, direct cells fate decisions that are important for cell proliferation and cell lineage decisions. Adipogenic differentiation contributes greatly to the development of white adipose tissue, involving of highly organized regulation by miRNAs. In the present study, we screened and identified 78 differently expressed miRNAs of porcine BMSCs during adipogenic differentiation. Of which, the role of miR-29c in regulating the proliferation and adipogenic differentiation was proved and detailed. Specifically, over-expression miR-29c inhibits the proliferation and adipogenic differentiation of BMSCs, which were reversed upon miR-29c inhibitor. Interference of IGF1 inhibits the proliferation and adipogenic differentiation of BMSCs. Mechanistically, miR-29c regulates the proliferation and adipogenic differentiation of BMSCs by targeting IGF1 and further regulating the MAPK pathway and the PI3K-AKT-mTOR pathway, respectively. In conclusion, we highlight the important role of miR-29c in regulating proliferation and adipogenic differentiation of BMSCs.

MicroRNA 29 modulates β-cell mitochondrial metabolism and insulin secretion via underlying miR-29-OXPHOS complex pathways

AIM

MicroRNAs (miRNAs) regulate β-cell function, and β-cell mitochondria and insulin secretion are perturbed in diabetes. We aimed to identify key miRNAs regulating β-cell mitochondrial metabolism and novel β-cell miRNA-mitochondrial pathways.

METHODS

TargetScan (http://www.targetscan.org/) was used to predict if 16 miRNAs implicated in β-cell function target 27 cis-eGenes implicated in mitochondrial activity. The expression of candidate miRNAs and insulin secretion after 24 and 1 h pre-incubation in 2.8, 11.1- and 16.7-mM glucose was measured in clonal INS-1 832/13 β-cells. MiR-29 silenced INS-1 832/13 cells were assessed for insulin secretion (glucose, pyruvate, and K+), target cis-eGene expression (Ndufv3 and Ndufa10 components of mitochondrial complex I (CI)), OXPHOS (CI-V) protein expression, and mitochondrial OXPHOS respiration/activity. The expression of differentially expressed miR-29 miRNAs was evaluated in Goto-Kakizaki (GK) rat, db/db mouse and type 2 diabetic (T2D) human islets, as well as NMRI mouse islets cultured under glucolipotoxic conditions.

RESULTS

MiR-29, miR-15 and miR-124 were predicted to regulate ~20 cis-eGenes, while miR-29 alone was predicted to regulate ≥12 of these in rat and human species. MiR-29 expression and insulin secretion were reduced in INS-1 832/13 cells after 24 h in elevated glucose. MiR-29 knockdown increased all tested insulin secretory responses, Nudfv3, Ndufa10, complex I and II expression, and cellular mitochondrial OXPHOS. MiR-29 expression was reduced in db/db islets but increased in GK rat and T2D human islets.

CONCLUSION

We conclude miR-29 is a key miRNA in regulating β-cell mitochondrial metabolism and insulin secretion via underlying miR-29-OXPHOS complex pathways. Furthermore, we infer reduced miR-29 expression compensatorily enhances insulin secretion under glucotoxicity.

Unveiling the role of microRNAs in metabolic dysregulation of Gestational Diabetes Mellitus

Gestational Diabetes Mellitus (GDM) presents a significant health concern globally, necessitating a comprehensive understanding of its metabolic intricacies for effective management. MicroRNAs (miRNAs) have emerged as pivotal regulators in GDM pathogenesis, influencing glucose metabolism, insulin signaling, and lipid homeostasis during pregnancy. Dysregulated miRNA expression, both upregulated and downregulated, contributes to GDM-associated metabolic abnormalities. Ethnic and temporal variations in miRNA expression underscore the multifaceted nature of GDM susceptibility. This review examines the dysregulation of miRNAs in GDM and their regulatory functions in metabolic disorders. We discuss the involvement of specific miRNAs in modulating key pathways implicated in GDM pathogenesis, such as glucose metabolism, insulin signaling, and lipid homeostasis. Furthermore, we explore the potential diagnostic and therapeutic implications of miRNAs in GDM management, highlighting the promise of miRNA-based interventions for mitigating the adverse consequences of GDM on maternal and offspring health.

Berberine attenuates obesity-induced insulin resistance by inhibiting miR-27a secretion

INTRODUCTION

Berberine (BBR) is an alkaloid found in plants. It has neuroprotective, anti-inflammatory and lipid-lowering activity. However, the efficacy of treatment with BBR and the mechanisms through which it acts need further study.

AIMS

This study investigated the therapeutic effects and the mechanism of action of BBR on obesity-induced insulin resistance in peripheral tissues.

METHODS

High-fat-fed C57BL/6J mice and low-fat-fed C57BL/6J mice with miR-27a overexpression were given BBR intervention (100 mg/kg, po), and the oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) were performed. Palmitic acid-stimulated hypertrophic adipocyte models were treated with BBR (10 μM). Related indicators and protein expression levels were examined.

RESULTS

The AUCs of the OGTT and the ITT in the BBR intervention group were reduced significantly (p < 0.01) (p < 0.05), and the serum biochemical parameters, including FBG, TC, TG and LDL-C were significantly reduced after BBR intervention. In the in vitro experiments, the triglyceride level and volume of lipid droplets decreased significantly after BBR intervention (p < 0.01) (p < 0.05). Likewise, BBR ameliorates skeletal muscle and pancreas insulin signalling pathways in vivo and in vitro.

DISCUSSION

The results showed that BBR significantly ameliorated insulin resistance, reduced body weight and percent body fat and improved serum biochemical parameters in mice. Likewise, BBR reduced triglyceride level and lipid droplet volume in hypertrophic adipocytes, BBR improved obesity effectively. Meanwhile, BBR ameliorated the histomorphology of the pancreas, and skeletal muscle and pancreas insulin related signalling pathways of islets in in vitro and in vivo experiments. The results further demonstrated that BBR inhibited miR-27a levels in serum from obese mice and supernatant of hypertrophic adipocytes. miR-27a overexpression in low-fat fed mice indicated that miR-27a caused insulin resistance, and BBR intervention significantly improved the miR-27a induced insulin resistance status.

CONCLUSION

This study demonstrates the important role of BBR in obesity-induced peripheral insulin resistance and suggest that the mechanism of its effect may be inhibition of miR-27a secretion.

MicroRNAs Associated with Metformin Treatment in the Diabetes Prevention Program

The Diabetes Prevention Program (DPP) randomized controlled trial demonstrated that metformin treatment reduced progression to type 2 diabetes (T2D) by 31% compared to placebo in adults with prediabetes. Circulating micro-ribonucleic acids (miRs) are promising biomarkers of T2D risk, but little is known about their associations with metformin regimens for T2D risk reduction. We compared the change in 24 circulating miRs from baseline to 2 years in a subset from DPP metformin intervention (n = 50) and placebo (n = 50) groups using Wilcoxon signed rank tests. Spearman correlations were used to evaluate associations between miR change and baseline clinical characteristics. Multiple linear regression was used to adjust for covariates. The sample was 73% female, 17% Black, 13% Hispanic, and 50 ± 11 years. Participants were obese, normotensive, prediabetic, and dyslipidemic. Change in 12 miR levels from baseline to 2 years was significantly different in the metformin group compared with placebo after adjusting for multiple comparisons: six (let-7c-5p, miR-151a-3p, miR-17-5p, miR-20b-5p, miR-29b-3p, and miR-93-5p) were significantly upregulated and six (miR-130b-3p, miR-22-3p, miR-222-3p, miR-320a-3p, miR-320c, miR-92a-3p) were significantly downregulated in the metformin group. These miRs help to explain how metformin is linked to T2D risk reduction, which may lead to novel biomarkers, therapeutics, and precision health strategies.

Epigenetic Mechanisms Modulated by Glucocorticoids With a Focus on Cushing Syndrome

In Cushing syndrome (CS), prolonged exposure to high cortisol levels results in a wide range of devastating effects causing multisystem morbidity. Despite the efficacy of treatment leading to disease remission and clinical improvement, hypercortisolism-induced complications may persist. Since glucocorticoids use the epigenetic machinery as a mechanism of action to modulate gene expression, the persistence of some comorbidities may be mediated by hypercortisolism-induced long-lasting epigenetic changes. Additionally, glucocorticoids influence microRNA expression, which is an important epigenetic regulator as it modulates gene expression without changing the DNA sequence. Evidence suggests that chronically elevated glucocorticoid levels may induce aberrant microRNA expression which may impact several cellular processes resulting in cardiometabolic disorders. The present article reviews the evidence on epigenetic changes induced by (long-term) glucocorticoid exposure. Key aspects of some glucocorticoid-target genes and their implications in the context of CS are described. Lastly, the effects of epigenetic drugs influencing glucocorticoid effects are discussed for their ability to be potentially used as adjunctive therapy in CS.

MicroRNAs Associated with Metformin Treatment in the Diabetes Prevention Program

The Diabetes Prevention Program (DPP) randomized controlled trial demonstrated that metformin treatment reduced progression to type 2 diabetes (T2D) by 31% compared to placebo in adults with prediabetes. Circulating micro-ribonucleic acids (miRs) are promising biomarkers of T2D risk, but little is known about their associations with metformin regimens for T2D risk reduction. We compared the change in 24 circulating miRs from baseline to 2 years in a subset from DPP metformin intervention (n = 50) and placebo (n = 50) groups using Wilcoxon signed rank tests. Spearman's correlations were used to evaluate associations between miR change and baseline clinical characteristics. Multiple linear regression was used to adjust for covariates. The sample was 73% female, 17% Black, 13% Hispanic, and 50 ± 11 years. Participants were obese, normotensive, prediabetic, and dyslipidemic. Change in 12 miR levels from baseline to 2 years was significantly different in the metformin group compared with placebo after adjusting for multiple comparisons: six (let-7c-5p, miR-151a-3p, miR-17-5p, miR-20b-5p, miR-29b-3p, and miR-93-5p) were significantly upregulated and six (miR-130b-3p, miR-22-3p, miR-222-3p, miR-320a-3p, miR-320c, miR-92a-3p) were significantly downregulated in the metformin group. These miRs help to explain how metformin is linked to T2D risk reduction, which may lead to novel biomarkers, therapeutics, and precision-health strategies.

Dietary Epigenetic Modulators: Unravelling the Still-Controversial Benefits of miRNAs in Nutrition and Disease

In the context of nutrient-driven epigenetic alterations, food-derived miRNAs can be absorbed into the circulatory system and organs of recipients, especially humans, and potentially contribute to modulating health and diseases. Evidence suggests that food uptake, by carrying exogenous miRNAs (xenomiRNAs), regulates the individual miRNA profile, modifying the redox homeostasis and inflammatory conditions underlying pathological processes, such as type 2 diabetes mellitus, insulin resistance, metabolic syndrome, and cancer. The capacity of diet to control miRNA levels and the comprehension of the unique characteristics of dietary miRNAs in terms of gene expression regulation show important perspectives as a strategy to control disease susceptibility via epigenetic modifications and refine the clinical outcomes. However, the absorption, stability, availability, and epigenetic roles of dietary miRNAs are intriguing and currently the subject of intense debate; additionally, there is restricted knowledge of their physiological and potential side effects. Within this framework, we provided up-to-date and comprehensive knowledge on dietary miRNAs' potential, discussing the latest advances and controversial issues related to the role of miRNAs in human health and disease as modulators of chronic syndromes.

Integrated Analysis of lncRNA-miRNA-mRNA Regulatory Network in Rapamycin-Induced Cardioprotection against Ischemia/Reperfusion Injury in Diabetic Rabbits

The inhibition of mammalian target of rapamycin (mTOR) with rapamycin (RAPA) provides protection against myocardial ischemia/reperfusion (I/R) injury in diabetes. Since interactions between transcripts, including long non-coding RNA (lncRNA), microRNA(miRNA) and mRNA, regulate the pathophysiology of disease, we performed unbiased miRarray profiling in the heart of diabetic rabbits following I/R injury with/without RAPA treatment to identify differentially expressed (DE) miRNAs and their predicted targets of lncRNAs/mRNAs. Results showed that among the total of 806 unique miRNAs targets, 194 miRNAs were DE after I/R in diabetic rabbits. Specifically, eight miRNAs, including miR-199a-5p, miR-154-5p, miR-543-3p, miR-379-3p, miR-379-5p, miR-299-5p, miR-140-3p, and miR-497-5p, were upregulated and 10 miRNAs, including miR-1-3p, miR-1b, miR-29b-3p, miR-29c-3p, miR-30e-3p, miR-133c, miR-196c-3p, miR-322-5p, miR-499-5p, and miR-672-5p, were significantly downregulated after I/R injury. Interestingly, RAPA treatment significantly reversed these changes in miRNAs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis indicated the participation of miRNAs in the regulation of several signaling pathways related to I/R injury, including MAPK signaling and apoptosis. Furthermore, in diabetic hearts, the expression of lncRNAs, HOTAIR, and GAS5 were induced after I/R injury, but RAPA suppressed these lncRNAs. In contrast, MALAT1 was significantly reduced following I/R injury, with the increased expression of miR-199a-5p and suppression of its target, the anti-apoptotic protein Bcl-2. RAPA recovered MALAT1 expression with its sponging effect on miR-199-5p and restoration of Bcl-2 expression. The identification of novel targets from the transcriptome analysis in RAPA-treated diabetic hearts could potentially lead to the development of new therapeutic strategies for diabetic patients with myocardial infarction.

Modulation of miR-29 influences myocardial compliance likely through coordinated regulation of calcium handling and extracellular matrix

MicroRNAs (miRNAs) control the expression of diverse subsets of target mRNAs, and studies have found miRNA dysregulation in failing hearts. Expression of miR-29 is abundant in heart, increases with aging, and is altered in cardiomyopathies. Prior studies demonstrate that miR-29 reduction via genetic knockout or pharmacologic blockade can blunt cardiac hypertrophy and fibrosis in mice. Surprisingly, this depended on specifically blunting miR-29 actions in cardiomyocytes versus fibroblasts. To begin developing more translationally relevant vectors, we generated a novel transgene-encoded miR-29 inhibitor (TuD-29) that can be incorporated into a viral-mediated gene therapy for cardioprotection. Here, we corroborate that miR-29 expression and activity is higher in cardiomyocytes versus fibroblasts and demonstrate that TuD-29 effectively blunts hypertrophic responses in cultured cardiomyocytes and mouse hearts. Furthermore, we found that adeno-associated virus (AAV)-mediated miR-29 overexpression in mouse hearts induces early diastolic dysfunction, whereas AAV:TuD-29 treatment improves cardiac output by increasing end-diastolic and stroke volumes. The integration of RNA sequencing and miRNA-target interactomes reveals that miR-29 regulates genes involved in calcium handling, cell stress and hypertrophy, metabolism, ion transport, and extracellular matrix remodeling. These investigations support a likely versatile role for miR-29 in influencing myocardial compliance and relaxation, potentially providing a unique therapeutic avenue to improve diastolic function in heart failure patients.

Muscle miRNAs are influenced by sex at baseline and in response to exercise

BACKGROUND

Sex differences in microRNA (miRNA) expression profiles have been found across multiple tissues. Skeletal muscle is one of the most sex-biased tissues of the body. MiRNAs are necessary for development and have regulatory roles in determining skeletal muscle phenotype and have important roles in the response to exercise in muscle. Yet there is limited research into the role and regulation of miRNAs in the skeletal muscle at baseline and in response to exercise, a well-known modulator of miRNA expression. The aim of this study was to investigate the effect of sex on miRNA expression in the skeletal muscle at baseline and after an acute bout of high-intensity interval exercise. A total of 758 miRNAs were measured using Taqman®miRNA arrays in the skeletal muscle of 42 healthy participants from the Gene SMART study (23 males and 19 females of comparable fitness levels and aged 18-45 years), of which 308 were detected. MiRNAs that differed by sex at baseline and whose change in expression following high-intensity interval exercise differed between the sexes were identified using mixed linear models adjusted for BMI and Wpeak. We performed in silico analyses to identify the putative gene targets of the exercise-induced, sex-specific miRNAs and overrepresentation analyses to identify enriched biological pathways. We performed functional assays by overexpressing two sex-biased miRNAs in human primary muscle cells derived from male and female donors to understand their downstream effects on the transcriptome.

RESULTS

At baseline, 148 miRNAs were differentially expressed in the skeletal muscle between the sexes. Interaction analysis identified 111 miRNAs whose response to an acute bout of high-intensity interval exercise differed between the sexes. Sex-biased miRNA gene targets were enriched for muscle-related processes including proliferation and differentiation of muscle cells and numerous metabolic pathways, suggesting that miRNAs participate in programming sex differences in skeletal muscle function. Overexpression of sex-biased miRNA-30a and miRNA-30c resulted in profound changes in gene expression profiles that were specific to the sex of the cell donor in human primary skeletal muscle cells.

CONCLUSIONS

We uncovered sex differences in the expression levels of muscle miRNAs at baseline and in response to acute high-intensity interval exercise. These miRNAs target regulatory pathways essential to skeletal muscle development and metabolism. Our findings highlight that miRNAs play an important role in programming sex differences in the skeletal muscle phenotype.

Multifaced roles of desmoplastic reaction and fibrosis in pancreatic cancer progression: Current understanding and future directions

Desmoplastic reaction is a fibrosis reaction that is characterized by a large amount of dense extracellular matrix (ECM) and dense fibrous stroma. Fibrotic stroma around the tumor has several different components, including myofibroblasts, collagen, and other ECM molecules. This stromal reaction is a natural response to the tissue injury process, and fibrosis formation is a key factor in pancreatic cancer development. The fibrotic stroma of pancreatic cancer is associated with tumor progression, metastasis, and poor prognosis. Reportedly, multiple processes are involved in fibrosis, which is largely associated with the upregulation of various cytokines, chemokines, matrix metalloproteinases, and other growth factors that promote tumor growth and metastasis. Fibrosis is also associated with immunosuppressive cell recruitment, such as regulatory T cells (Tregs) with suppressing function to antitumor immunity. Further, dense fibrosis restricts the flow of nutrients and oxygen to the tumor cells, which can contribute to drug resistance. Furthermore, the dense collagen matrix can act as a physical barrier to block the entry of drugs into the tumor, thereby further contributing to drug resistance. Thus, understanding the mechanism of desmoplastic reaction and fibrosis in pancreatic cancer will open an avenue to innovative medicine and improve the prognosis of patients suffering from this disease.

MicroRNA therapeutics and nucleic acid nano-delivery systems in bacterial infection: a review

Bacteria that have worked with humans for thousands of years pose a major threat to human health even today, as drug resistance has become a prominent problem. Compared to conventional drug therapy, nucleic acid-based therapies are a promising and potential therapeutic strategy for diseases in which nucleic acids are delivered through a nucleic acid delivery system to regulate gene expression in specific cells, offering the possibility of curing intractable diseases that are difficult to treat at this stage. Among the many nucleic acid therapeutic ideas, microRNA, a class of small nucleic acids with special properties, has made great strides in biology and medicine in just over two decades, showing promise in preclinical drug development. In this review, we introduce recent advances in nucleic acid delivery systems and their clinical applications, highlighting the potential of nucleic acid therapies, especially miRNAs extracted from traditional herbs, in combination with the existing set of nucleic acid therapeutic systems, to potentially open up a new line of thought in the treatment of cancer, viruses, and especially bacterial infectious diseases.

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.

Gene expression inhibitors for the treatment of liver fibrosis: drugs under preclinical and early clinical investigation

INTRODUCTION

Liver fibrosis represents an unmet medical condition with growing incidence and only limited therapeutic options. Interfering with dysregulated gene expression was considered a specific treatment approach, and we are here reviewing the current options to modulate transcription and translation with small molecule inhibitors of involved enzymes, transcription factors or by using non-coding RNA molecules (RNA interference) or DNA antisense oligonucleotides. Despite promising results in preclinical models, only limited data are available from studies in humans.

AREAS COVERED

This expert opinion provides a general overview of how to interfere with gene expression (transcription and translation) and highlighting recent achievements in liver fibrosis.

EXPERT OPINION

Many compounds that were explored to modulate gene expression in liver fibrosis (models) were developed as anti-cancer agents. Their use in humans with impaired liver function is often impaired by the lack of specificity to inhibit only fibrosis-related genes in the liver and by associated general toxicity and narrow therapeutic windows. RNAi approaches show a higher degree of specificity and potentially less systemic toxicity. Clinical development in liver fibrosis requires close interaction between pharmaceutical companies and regulatory authorities to address topics like relevant (surrogate) endpoints to achieve meaningful readouts faster.

Circulating microRNAs for Early Diagnosis of Ovarian Cancer: A Systematic Review and Meta-Analysis

In this study, we conducted a systematic review and meta-analysis to summarize and evaluate the global research potential of different circulating miRNAs as an early diagnostic biomarker for OC. A systematic literature search for relevant studies was conducted in June 2020 and followed up in November 2021. The search was conducted in English databases (PubMed, ScienceDirect). The primary search resulted in a total of 1887 articles, which were screened according to the prior established inclusion and exclusion criteria. We identified 44 relevant studies, of which 22 were eligible for the quantitative meta-analysis. Statistical analysis was performed using the Meta-package in Rstudio. Standardized mean differences (SMD) of relative levels between control subjects and OC patients were used to evaluate the differential expression. All studies were quality evaluated using a Newcastle-Ottawa Scale. Based on the meta-analysis, nine miRNAs were identified as dysregulated in OC patients compared to controls. Nine were upregulated in OC patients compared to controls (miR-21, -125, -141, -145, -205, -328, -200a, -200b, -200c). Furthermore, miR-26, -93, -106 and -200a were analyzed, but did not present an overall significant difference between OC patients and controls. These observations should be considered when performing future studies of circulating miRNAs in relation to OC: sufficient size of clinical cohorts, development of consensus guidelines for circulating miRNA measurements, and coverage of previously reported miRNAs.

Circulating microRNA as Biomarkers for Gestational Diabetes Mellitus-A Systematic Review and Meta-Analysis

Gestational diabetes mellitus (GDM) is a severe pregnancy complication for both the woman and the child. Women who suffer from GDM have a greater risk of developing Type 2 diabetes mellitus (T2DM) later in life. Identification of any potential biomarkers for the early prediction of gestational diabetes can help prevent the disease in women with a high risk. Studies show microRNA (miRNA) as a potential biomarker for the early discovery of GDM, but there is a lack of clarity as to which miRNAs are consistently altered in GDM. This study aimed to perform a systematic review and meta-analysis to investigate miRNAs associated with GDM by comparing GDM cases with normoglycemic controls. The systematic review was performed according to PRISMA guidelines with searches in PubMed, Web of Science, and ScienceDirect. The primary search resulted in a total of 849 articles, which were screened according to the prior established inclusion and exclusion criteria. Following the screening of articles, the review was based on the inclusion of 35 full-text articles, which were evaluated for risk of bias and estimates of quality, after which data were extracted and relative values for miRNAs were calculated. A meta-analysis was performed for the miRNA species investigated in three or more studies: MiR-29a, miR-330, miR-134, miR-132, miR-16, miR-223, miR-155, miR-122, miR-17, miR-103, miR-125, miR-210, and miR-222. While some miRNAs showed considerable between-study variability, miR-29a, miR-330, miR-134, miR-16, miR-223, and miR-17 showed significant overall upregulation in GDM, while circulating levels of miR-132 and miR-155 were decreased among GDM patients, suggesting further studies of these as biomarkers for early GDM discovery.

Role of noncoding RNAs in liver fibrosis

Liver fibrosis is a wound-healing response following chronic liver injury caused by hepatitis virus infection, obesity, or excessive alcohol. It is a dynamic and reversible process characterized by the activation of hepatic stellate cells and excess accumulation of extracellular matrix. Advanced fibrosis could lead to cirrhosis and even liver cancer, which has become a significant health burden worldwide. Many studies have revealed that noncoding RNAs (ncRNAs), including microRNAs, long noncoding RNAs and circular RNAs, are involved in the pathogenesis and development of liver fibrosis by regulating signaling pathways including transforming growth factor-β pathway, phosphatidylinositol 3-kinase/protein kinase B pathway, and Wnt/β-catenin pathway. NcRNAs in serum or exosomes have been reported to tentatively applied in the diagnosis and staging of liver fibrosis and combined with elastography to improve the accuracy of diagnosis. NcRNAs mimics, ncRNAs in mesenchymal stem cell-derived exosomes, and lipid nanoparticles-encapsulated ncRNAs have become promising therapeutic approaches for the treatment of liver fibrosis. In this review, we update the latest knowledge on ncRNAs in the pathogenesis and progression of liver fibrosis, and discuss the potentials and challenges to use these ncRNAs for diagnosis, staging and treatment of liver fibrosis. All these will help us to develop a comprehensive understanding of the role of ncRNAs in liver fibrosis.

The role of microRNAs in the molecular link between circadian rhythm and autism spectrum disorder

Circadian rhythm regulates physiological cycles of awareness and sleepiness. Melatonin production is primarily regulated by circadian regulation of gene expression and is involved in sleep homeostasis. If the circadian rhythm is abnormal, sleep disorders, such as insomnia and several other diseases, can occur. The term 'autism spectrum disorder (ASD)' is used to characterize people who exhibit a certain set of repetitive behaviors, severely constrained interests, social deficits, and/or sensory behaviors that start very early in life. Because many patients with ASD suffer from sleep disorders, sleep disorders and melatonin dysregulation are attracting attention for their potential roles in ASD. ASD is caused by abnormalities during the neurodevelopmental processes owing to various genetic or environmental factors. Recently, the role of microRNAs (miRNAs) in circadian rhythm and ASD have gained attraction. We hypothesized that the relationship between circadian rhythm and ASD could be explained by miRNAs that can regulate or be regulated by either or both. In this study, we introduced a possible molecular link between circadian rhythm and ASD. We performed a thorough literature review to understand their complexity.

Circulating miRNAs associated with nonalcoholic fatty liver disease

MicroRNAs (miRNAs) are secreted from cells as either protein-bound or enclosed in extracellular vesicles. Circulating liver-derived miRNAs are modifiable by weight-loss or insulin-sensitizing treatments, indicating that they could be important biomarker candidates for diagnosis, monitoring, and prognosis in nonalcoholic liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Unfortunately, the noninvasive diagnosis of NASH and fibrosis remains a key challenge, which limits case finding. Current diagnostic guidelines, therefore, recommend liver biopsies, with risks of pain and bleeding for the patient and substantial healthcare costs. Here, we summarize mechanisms of RNA secretion and review circulating RNAs associated with NAFLD and NASH for their biomarker potential. Few circulating miRNAs are consistently associated with NAFLD/NASH: miR-122, miR-21, miR-34a, miR-192, miR-193, and the miR-17-92 miRNA-cluster. The hepatocyte-enriched miRNA-122 is consistently increased in NAFLD and NASH but decreased in liver cirrhosis. Circulating miR-34a, part of an existing diagnostic algorithm for NAFLD, and miR-21 are consistently increased in NAFLD and NASH. MiR-192 appears to be prominently upregulated in NASH compared with NAFDL, whereas miR-193 was reported to distinguish NASH from fibrosis. Various members of miRNA cluster miR-17-92 are reported to be associated with NAFLD and NASH, although with less consistency. Several other circulating miRNAs have been reported to be associated with fatty liver in a few studies, indicating the existence of more circulating miRNAs with relevant as diagnostic markers for NAFLD or NASH. Thus, circulating miRNAs show potential as biomarkers of fatty liver disease, but more information about phenotype specificity and longitudinal regulation is needed.

Circulating microRNAs associated with gestational diabetes mellitus: useful biomarkers?

Different types of small non-coding RNAs, especially miRNAs, may be found in the circulation, either protein-bound or enclosed in extracellular vesicles. During gestation, and particularly during gestational diabetes mellitus (GDM), the levels of several miRNAs are altered. Worldwide the incidence of GDM is increasing, in part driven by the current obesity epidemic. This is a point of public health concern because offspring of women with GDM frequently suffer from short- and long-term complications of maternal GDM. This has prompted the investigation of whether levels of specific miRNA species, detected early in gestation, may be used as diagnostic or prognostic markers for the development of GDM. Here, we summarize the mechanisms of RNA secretion and review circulating miRNAs associated with GDM. Several miRNAs are associated with GDM: miR-29a-3p and miR-29b-3p are generally upregulated in GDM pregnancies, also when measured prior to the development of GDM, while miR-16-5p is consistently upregulated in GDM pregnancies, especially in late gestation. miR-330-3p in circulation is increased in late gestation GDM women, especially in those with poor insulin secretion. miR-17-5p, miR-19a/b-3p, miR-223-3p, miR-155-5p, miR-125-a/b-5p, miR-210-3p and miR-132 are also associated with GDM, but less so and with more contradictory results reported. There could be a publication bias as miRNAs identified early are investigated the most, suggesting that it is likely that additional, more recently detected miRNAs could also be associated with GDM. Thus, circulating miRNAs show potential as biomarkers of GDM diagnosis or prognosis, especially multiple miRNAs containing prediction algorithms show promise, but further studies are needed.

The Related Metabolic Diseases and Treatments of Obesity

Obesity is a chronic disease characterized by the abnormal or excessive accumulation of body fat, affecting more than 1 billion people worldwide. Obesity is commonly associated with other metabolic disorders, such as type 2 diabetes, non-alcoholic fatty liver disease, cardiovascular diseases, chronic kidney disease, and cancers. Factors such as a sedentary lifestyle, overnutrition, socioeconomic status, and other environmental and genetic conditions can cause obesity. Many molecules and signaling pathways are involved in the pathogenesis of obesity, such as nuclear factor (NF)-κB, Toll-like receptors (TLRs), adhesion molecules, G protein-coupled receptors (GPCRs), programmed cell death 1 (PD-1)/programmed death-ligand 1 (PD-L1), and sirtuin 1 (SIRT1). Commonly used strategies of obesity management and treatment include exercise and dietary change or restriction for the early stage of obesity, bariatric surgery for server obesity, and Food and Drug Administration (FDA)-approved medicines such as semaglutide and liraglutide that can be used as monotherapy or as a synergistic treatment. In addition, psychological management, especially for patients with obesity and distress, is a good option. Gut microbiota plays an important role in obesity and its comorbidities, and gut microbial reprogramming by fecal microbiota transplantation (FMT), probiotics, prebiotics, or synbiotics shows promising potential in obesity and metabolic syndrome. Many clinical trials are ongoing to evaluate the therapeutic effects of different treatments. Currently, prevention and early treatment of obesity are the best options to prevent its progression to many comorbidities.

miRNA transcriptome and myofiber characteristics of lamb skeletal muscle during hypertrophic growth1

Postnatal muscle growth is achieved through hypertrophy of the muscle fibers and is impacted by the activity of satellite cells, the quiescent muscle stem cell. Several miRNAs are preferentially expressed in skeletal muscle and could provide a mechanism for increasing muscle hypertrophy through satellite cell proliferation and/or differentiation. The objectives of this study were to: 1) Characterize the miRNA transcriptome of the longissimus thoracis et lumborum muscle at several developmental timepoints [gestational d 85 (PN1), 110 (PN2), 133 (PN3), postnatal d 42 (PW1), 65 (PW2), 243 (MAT)] during muscle hypertrophy in lambs, and 2) examine miR-29a, identified in sequencing to be differentially regulated across development, loss of function on satellite cell proliferation and differentiation. Muscle fiber characteristics showed drastic increases (p < 0.0001) in fiber size and alterations in muscle fiber type occur during pre and postnatal development. miRNA sequencing comparisons were performed in developmental order (PN1 vs. PN2, PN2 vs. PN3, PN3 vs. PW1, PW1 vs. PW2, PW2 vs. MAT). There were 184 differentially expressed (P _adj < 0.05) miRNA, 142 unique miRNA, from all 5 comparisons made. The transitional stage (PN3 vs. PW1) had the largest number (115) of differentially expressed miRNA. Inhibition of miR-29a in satellite cell culture increased (p < 0.05) cell proliferation and differentiation capacity. Characterization of the miRNA transcriptome provides valuable insights into the miRNA involved in muscle fiber hypertrophy and the potential importance of the transitional period.