miRNAs In Relation Research Articles

Seasonal influence on miRNA expression dynamics of extracellular vesicles in equine follicular fluid.

Ovarian follicular fluid (FF) is a dynamic environment that changes with the seasons, affecting follicle development, ovulation, and oocyte quality. Cells in the follicles release tiny particles called extracellular vesicles (EVs) containing vital regulatory molecules, such as microRNAs (miRNAs). These miRNAs are pivotal in facilitating communication within the follicles through diverse signaling and information transfer forms. EV-coupled miRNA signaling is implicated to be associated with ovarian function, follicle and oocyte growth and response to various environmental insults. Herein, we investigated how seasonal variations directly influence the ovulatory and anovulatory states of ovarian follicles and how are they associated with follicular fluid EV-coupled miRNA dynamics in horses. Ultrasonographic monitoring and follicular fluid aspiration of preovulatory follicles in horses during the anovulatory (spring: non-breeding) and ovulatory (spring, summer, and fall: breeding) seasons and subsequent EV isolation and miRNA profiling identified significant variation in EV-miRNA cargo content. We identified 97 miRNAs with differential expression among the groups and specific clusters of miRNAs involved in the spring transition (miR-149, -200b, -206, -221, -328, and -615) and peak breeding period (including miR-143, -192, -451, -302b, -100, and let-7c). Bioinformatic analyses showed enrichments in various biological functions, e.g., transcription factor activity, transcription and transcription regulation, nucleic acid binding, sequence-specific DNA binding, p53 signaling, and post-translational modifications. Cluster analyses revealed distinct sets of significantly up- and down-regulated miRNAs associated with spring anovulatory (Cluster 1) and summer ovulation-the peak breeding season (Clusters 4 and 6). The findings from the current study shed light on the dynamics of FF-EV-coupled miRNAs in relation to equine ovulatory and anovulatory seasons, and their roles in understanding the mechanisms involved in seasonal shifts and ovulation during the breeding season warrant further investigation.

The Role of MicroRNAs and Stem cells in Rheumatoid Arthritis: A Therapeutic and Diagnostic Approach.

In autoimmune illnesses like Rheumatoid Arthritis (RA), the synovium is constantly inflamed, and joints are ruptured. It is becoming increasingly clear that stem cells, especially notably mesenchymal stem cells (MSCs) and microRNAs (miRNAs), play important roles in the onset and amelioration of RA. There is mounting evidence from both animal and human studies that suggests a potentially safe and effective method to treat RA and other intractable diseases by reducing chronic inflammation and spurring tissue regeneration through the transplantation of multipotent adult stem cells, such as mesenchymal stromal/stem cells. To control gene expression, which impacts immune cell differentiation and inflammatory pathways, microRNAs (miRNAs) are crucial, even though MSCs can self-renew and modify inflammatory reactions. The pathophysiology of RA is marked by the dysregulation of immunological responses and the proliferation of fibroblast-like synoviocytes, which are linked to the aberrant expression of specific microRNAs (miRNAs). This study mainly aims to examine the therapeutic implications of these microRNAs (miRNAs) in relation to RA, as they can function as diagnostic and prognostic indicators. This study explores the functions of microRNAs (miRNAs) and stem cells in rheumatoid arthritis (RA), drawing attention to the relevance of these biological processes and the potential for creating novel therapeutic strategies to improve patient outcomes.

The Untapped Biomarker Potential of MicroRNAs for Health Risk-Benefit Analysis of Vaping vs. Smoking.

Despite the popularity of electronic cigarettes (e-cigs) among adolescent never-smokers and adult smokers seeking a less pernicious substitute for tobacco cigarettes, the long-term health impact of vaping is largely unknown. Like cigarette smoke, e-cig vapor contains harmful and potentially harmful compounds, although in fewer numbers and at substantially lower concentrations. Many of the same constituents of e-cig vapor and cigarette smoke induce epigenetic changes that can lead to the dysregulation of disease-related genes. MicroRNAs (MiRNAs) are key regulators of gene expression in health and disease states. Extensive research has shown that miRNAs play a prominent role in the regulation of genes involved in the pathogenesis of smoking-related diseases. However, the use of miRNAs for investigating the disease-causing potential of vaping has not been fully explored. This review article provides an overview of e-cigs as a highly consequential electronic nicotine delivery system, describes trends in e-cig use among adolescents and adults, and discusses the ongoing debate on the public health impact of vaping. Highlighting the significance of miRNAs in cell biology and disease, it summarizes the published and ongoing research on miRNAs in relation to gene regulation and disease pathogenesis in e-cig users and in vitro experimental settings. It identifies gaps in knowledge and priorities for future research while underscoring the need for empirical evidence that can inform the regulation of tobacco products to protect youth and promote public health.

Regulatory roles of miRNA-530 in the post-transcriptional regulation of NF-κB signaling pathway through targeted modulation of IκBα in Sebastesschlegelii

MicroRNAs (miRNAs) are a crucial type of non-coding RNAs involved in post-transcriptional regulation. The playing essential regulatory roles in the NF-κB signaling pathway and modulate the host immune response to diverse pathogens by targeting IκBα. However, the regulatory mechanism of miRNAs in relation with IκBα in Sebastes schlegelii remains unclear. In our study, we identified two copies of IkBα gene in black rockfish (Sebastes schlegelii), namely IkBα1 and IkBα2. Moreover, we have discovered that miRNA-530 can activate the NF-κB signaling pathway by inhibiting the expression of IκBα, thereby inducing the inflammatory response. This project comprehensively investigated the interactive regulatory roles of miRNA-530 in the NF-κB signaling pathway at both cellular and in vivo levels, while also elucidating the regulatory relationships between miRNA-530 and IκBα. In conclusion, our research confirmed that miRNA-530 can target the 3′UTR region of IκBα, resulting in a decrease in the expression of IκBα at the post-transcriptional level and inhibiting its translation. The findings contribute to the understanding of the regulatory network of non-coding RNA in teleosts and its subsequent regulation of the NF-κB signaling pathway by miRNAs.

Specific circulating miRNAs are associated with plasma lipids in a healthy American cohort.

Low-density lipoprotein cholesterol (LDL-c) is both a therapeutic target and a risk factor for cardiovascular disease (CVD). MicroRNA (miRNA) has been shown to regulate cholesterol homeostasis, and miRNA in blood circulation has been linked to hypercholesterolemia. However, few studies to date have associated miRNA with phenotypes like LDL-c in a healthy population. To this end, we analyzed circulating miRNA in relation to LDL-c in a healthy cohort of 353 participants using two separate bioinformatic approaches. The first approach found that miR-15b-5p and miR-16-5p were upregulated in individuals with at-risk levels of LDL-c. The second approach identified two miRNA clusters, one that positively and a second that negatively correlated with LDL-c. Included in the cluster that positively correlated with LDL-c were miR-15b-5p and miR-16-5p, as well as other miRNA from the miR-15/107, miR-30, and let-7 families. Cross-species analyses suggested that several miRNAs that associated with LDL-c are conserved between mice and humans. Finally, we examined the influence of diet on circulating miRNA. Our results robustly linked circulating miRNA with LDL-c, suggesting that miRNA could be used as biomarkers for hypercholesterolemia or targets for developing cholesterol-lowering drugs.NEW & NOTEWORTHY This study explored the association between circulating microRNA (miRNA) and low-density lipoprotein cholesterol (LDL-c) in a healthy population of 353 participants. Two miRNAs, miR-15b-5p and miR-16-5p, were upregulated in individuals with at-risk LDL-c levels. Several miRNA clusters were positively and negatively correlated with LDL-c and are known to target mRNA involved in lipid metabolism. The study also investigated the influence of diet on circulating miRNA, suggesting potential biomarkers for hypercholesterolemia.

Decoding the secrets of longevity: unraveling nutraceutical and miRNA-Mediated aging pathways and therapeutic strategies.

MicroRNAs (miRNAs) are short RNA molecules that are not involved in coding for proteins. They have a significant function in regulating gene expression after the process of transcription. Their participation in several biological processes has rendered them appealing subjects for investigating age-related disorders. Increasing data indicates that miRNAs can be influenced by dietary variables, such as macronutrients, micronutrients, trace minerals, and nutraceuticals. This review examines the influence of dietary factors and nutraceuticals on the regulation of miRNA in relation to the process of aging. We examine the present comprehension of miRNA disruption in age-related illnesses and emphasize the possibility of dietary manipulation as a means of prevention or treatment. Consolidating animal and human research is essential to validate the significance of dietary miRNA control in living organisms, despite the abundance of information already provided by several studies. This review elucidates the complex interaction among miRNAs, nutrition, and aging, offering valuable insights into promising areas for further research and potential therapies for age-related disorders.

Selected miRNAs in oropharyngeal squamous cell carcinoma (OPSCC) with HPV and EBV coinfection

Abstract Different levels of miR-625-5p, miR-31-5p and miR-5100 have been reported in many cancers. Viral infections have been linked to miRNA levels in tumors, including those in the head and neck, but a large proportion of studies only include infections with a single virus. The aim of the present study is to assess the level of miR-625-5p, 31-5p and 5100 in oropharyngeal cancer with single HPV and EBV infections and HPV/EBV co-infection. The study examined 128 oropharyngeal cancer patients infected with EBV and HPV alone or co-infected with both viruses. For the determination of miRNAs, the enzyme immunoassays was used. Both miR-625-5p and miR-31-5p were higher in the HPV/EBV co-infection than in the single infection HPV or EBV. However, in the case of miR-5100, the values in co-infection were lower than in a single EBV infection. The analysis of miRNAs in relation to the histological grade and tumor classification, nodes (TN) showed that in poorly differentiated tumors the level of the studied miRNAs was higher compared to well-differentiated lesions, and in cases with larger tumor sizes and lymph node involvement, the miRNA values were both higher in single infections and co-infections.

MiR-619-5p and cardiogenic shock in patients with ST-segment elevation myocardial infarction.

Cardiogenic shock (CS) is a severe myocardial dysfunction secondary to various cardiac conditions including ST-segment elevation acute myocardial infarction (STEMI) and associated with a high risk of death. Little is known on epigenetic determinants in CS. Here, we investigated plasma miRNAs in relation to CS stratification in STEMI-patients. STEMI-patients (n = 49), with (CS, n = 25) and without CS (non-CS, n = 24) fulfilling inclusion criteria were included from HSCSP-cohort (Derivation-cohort). CS-miRNAs were analysed by Affymetrix-microarray and RT-PCR. Results were validated in a second cohort of CS-patients (CardShock: n = 35) with similar inclusion/exclusion criteria as the derivation cohort. In silico analysis were performed to identify potential miRNA target genes. Of the 5-miRNA signature obtained from microarray analysis, miR-619-5p showed higher levels in CS than in Non-CS patients (p = .003) and discriminating power for CS by ROC (AUC: .752, p = .003). miR-619-5p directly associated with risk scores [GRACE, p = .001; CardShock, p < .001]. Furthermore, miR-619-5p showed discrimination power for death in CS. Thus, miRNA levels were significantly higher in patients with mortality outcome both in the Derivation HSCSP-cohort (p = .02; AUC: .78 ± .095) and the Validation CardShock-cohort (p = .017; AUC: .737 ± .086) By in silico analysis, miR-619-5p target genes and TNF-alpha were involved in the regulation of inflammation. miR-619-5p and TNF-alpha levels discriminated mortality outcome in CS-patients during 30-day follow-up (Validation-Cohort: ROC: .812, p = .002; HR: 9.99, p = .003). Up-regulation of miR-619-5p is found in the plasma of STEMI-patients with CS and mortality outcome. These findings highlight the specificity of epigenetic regulation of inflammation on the disease severity of MI.

Abstract A001: Transcriptomic and microRNA profiling revealed novel therapeutic targets for breast cancer subtypes

Abstract Numerous studies suggested breast cancer (BC) from the Middle East and North Africa (MENA) to be presented at younger age with advanced tumor grade, suggesting underlying biological differences. Given the limited transcriptomic profiling data on BC from the MENA region, we performed mRNA and microRNA (miRNA) transcriptomic profiling on a local cohort of BC (n=96) from Qatar. Our data revealed the differentially expressed genes and miRNAs in relation to BC molecular subtypes (HR+, HER2+, HER2+HR+, and TNBC), tumor grade (high vs low), patients’ age (young (≤ 40) vs old (&amp;gt; 40)), and ethnicity (MENA vs non-MENA). Our data revealed close similarity between TNBC and HER2+, while the transcriptome of HER2+HR+ tumor was similar to that from HR+ tumors. Integrated network analysis identified complex miRNA-mRNA regulatory networks in each BC molecular subtype, in high vs low grade tumors, in tumors from young vs old, and in tumors from MENA vs non-MENA, thus implicating miRNA-mediated gene regulation as an key mechanism in shaping the transcriptome of BC. Integration of our transcriptomic data with CRISPR-Cas9 functional screen data and the Drug-Gene Interaction Database identified numerous dependencies and therapeutic vulnerabilities for each BC molecular subtype. Among those, CDC123 was functionally validated as potential therapeutic target for TNBC. Survival analyses identified mRNA and miRNA-based signatures predicative of relapse free survival (RFS), which were validated in larger BC cohorts. Our data provides comprehensive transcriptomic profiling and unraveled the miRNA-mRNA regulatory networks in BC patients from the region and identified numerous actionable gene targets, employing integrated approach. Findings from the current study have potential implications to improve the current standard-of-care for BC from the MENA as well as patients from other ethnicities. Citation Format: Ramesh Elango, Radhakrishnan Vishnubalaji, Sameera Rashid, Nehad Alajez. Transcriptomic and microRNA profiling revealed novel therapeutic targets for breast cancer subtypes [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr A001.

MicroRNAs as Potential Biomarkers of Environmental Exposure to Polycyclic Aromatic Hydrocarbons and Their Link with Inflammation and Lung Cancer

Exposure to atmospheric air pollution containing volatile organic compounds such as polycyclic aromatic hydrocarbons (PAHs) has been shown to be a risk factor in the induction of lung inflammation and the initiation and progression of lung cancer. MicroRNAs (miRNAs) are small single-stranded non-coding RNA molecules of ~20–22 nucleotides that regulate different physiological processes, and their altered expression is implicated in various pathophysiological conditions. Recent studies have shown that the regulation of gene expression of miRNAs can be affected in diseases associated with outdoor air pollution, meaning they could also be useful as biomarkers of exposure to environmental pollution. In this article, we review the published evidence on miRNAs in relation to exposure to PAH pollution and discuss the possible mechanisms that may link these compounds with the expression of miRNAs.

The Pathological Role of miRNAs in Endometriosis.

Association studies investigating miRNA in relation to diseases have consistently shown significant alterations in miRNA expression, particularly within inflammatory pathways, where they regulate inflammatory cytokines, transcription factors (such as NF-κB, STAT3, HIF1α), and inflammatory proteins (including COX-2 and iNOS). Given that endometriosis (EMS) is characterized as an inflammatory disease, albeit one influenced by estrogen levels, it is natural to speculate about the connection between EMS and miRNA. Recent research has indeed confirmed alterations in the expression levels of numerous microRNAs (miRNAs) in both endometriotic lesions and the eutopic endometrium of women with EMS, when compared to healthy controls. The undeniable association of miRNAs with EMS hints at the emergence of a new era in the study of miRNA in the context of EMS. This article reviews the advancements made in understanding the pathological role of miRNA in EMS and its association with EMS-associated infertility. These findings contribute to the ongoing pursuit of developing miRNA-based therapeutics and diagnostic markers for EMS.

P-064 MicroRNAs as potential biomarkers for male infertility related to Testicular Germ Cell Tumors

Abstract Study question Could microRNAs represent efficient biomarkers to evaluate male infertility and the tendency of develop testicular germ cell tumors (TGCTs)? Summary answer The up-regulation of miR-193a-5p, miR-93-5p and let-7c-5p in TGCT patients with impaired spermiogram could represent a molecular signature of male infertility related to TGCTs. What is known already Testicular germ cell tumors (TGCTs) are the most recurrent tumors in young men with the highest incidence between the ages of 20 and 40 years and represent more than 60% of all cancers diagnosed in this age range. Several studies have shown a correlation between TGCTs and infertility, not only because infertility could be a consequence of testicular damage due to TGCTs but also because infertility may represent a risk factor for TGCTs. Therefore, it is important to find valid biomarkers that could be used to specifically identify infertility related to an increased risk of developing TGCTs. Study design, size, duration From March 2021 to January 2023, we collected 44 seminal plasma samples: 17 from TGCT patients who were undergoing sperm cryopreservation prior to chemotherapy, 14 with impaired spermiogram (IS) and 3 with normal spermiogram (NS) and 27 from control patients, 16 with IS and 11 with NS, undergoing assisted fertilization techniques. We evaluated the potential role of miRNAs as non-invasive biomarkers, analyzing the differential expression of 84 miRNAs in relation to cancer, infertility and both. Participants/materials, setting, methods Semen samples were placed 30’/37 °C, seminal plasma was purified using density-gradient centrifugation and stored at -80 °C. RNA was purified by Qiagen miRNeasy Serum/Plasma Kit and analyzed by miRCURY LNA miRNA SYBR®Green PCR_SerumPlasma, 96-well plate. We applied the 2−ΔΔCT method and statistical significance was evaluated by Significance Analysis of Microarrays, screened by p-values ≤ 0.05. We performed a Pearson correlation analysis applying two-sided p-values. miRTarBASE, MIENTURNET and Cytoscape were used for bioinformatics analysis. Main results and the role of chance In the four comparisons, we found 9 differentially expressed microRNAs. In particular, miR-221-3p, miR-222-3p, miR-204-5p and miR-205-5p down regulation would appear to be related to infertility, regardless to the cancer. Conversely, all TGCT patients shown an up-regulation of miR-376c-3p. Interestingly, up-regulation of miR-193a-5p, miR-93-5p and let-7c-5p specifically discriminates the infertile cancer patients vs other categories. Moreover, these three miRNAs showed a significant positive correlation both in cancer patients with impaired spermiogram and in infertile controls. This correlation demonstrates that their expression changes in the same way in the single samples and strongly suggests their role as early biomarkers of TGCT patients with impaired spermiogram. From the KEGG pathway analysis has emerged that DE miRNAs are involved in several signaling pathway, such as MAPK, mTOR, p53, PI3K-Akt, AMPK, FoxO, JAK-STAT, Ras, Estrogen signaling pathways, as well as cell cycle and cellular senescence. Moreover, from the Diseases Ontology analysis we found than those miRNAs are involved in germ cell tumor, male reproductive organ cancer, prostate cancer, male infertility and azoospermia. Limitations, reasons for caution The data must be validated by single assays in higher number of samples. These experiments are currently ongoing. Wider implications of the findings Three of the DE miRNAs are overexpressed in TGCT with impaired spermiogram patients. Specifically, they are over-expressed in TGCT with impaired spermiogram compared to infertile controls, so they may represent specific biomarkers able to discriminate, among the young men with infertility, those with higher risk of develop testicular cancer. Trial registration number Not applicable

MiRNAs role in glioblastoma pathogenesis and targeted therapy: Signaling pathways interplay.

High mortality and morbidity rates and variable clinical behavior are hallmarks of glioblastoma (GBM), the most common and aggressive primary malignant brain tumor. Patients with GBM often have a dismal outlook, even after undergoing surgery, postoperative radiation, and chemotherapy, which has fueled the search for specific targets to provide new insights into the development of contemporary therapies. The ability of microRNAs (miRNAs/miRs) to posttranscriptionally regulate the expression of various genes and silence many target genes involved in cell proliferation, cell cycle, apoptosis, invasion, angiogenesis, stem cell behavior and chemo- and radiotherapy resistance makes them promising candidates as prognostic biomarkers and therapeutic targets or factors to advance GBM therapeutics. Hence, this review is like a crash course in GBM and how miRNAs related to GBM. Here, we will outline the miRNAs whose role in the development of GBM has been established by recent in vitro or in vivo research. Moreover, we will provide a summary of the state of knowledge regarding oncomiRs and tumor suppressor (TS) miRNAs in relation to GBM with an emphasis on their potential applications as prognostic biomarkers and therapeutic targets.

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.

In silico Analyzes of miRNAs Associated with Root and Tuber in S. commersonii

Potato is an industrial plant that is produced and consumed globally due to its cheapness, high yield in the unit area, high nutritional values. It is used in many different fields. It has been stated that wild species with various characteristics can be used in studies to increase productivity because they have greater rate of genetic variation than their domesticated relatives. One of the wild species of potato found in nature is S. commersonii Dunal. It is more resistant to many stresses than cultivated potato S. tuberosum L. Also, its tuber has better quality due to the fact that it contains a higher proportion of dry matter. With the aim of determining the effects of miRNAs in tuber production and root characteristics relation we aimed to detect miRNAs in two transcriptome libraries of S. commersonii. In this study miRNAs were evaluated for the first time in the wild potato transcriptome data using in silico analysis. A number of miRNAs were identified, and their potential roles in tuber were discussed.

Progression of Type 1 Diabetes: Circulating MicroRNA Expression Profiles Changes from Preclinical to Overt Disease.

Objectives To evaluate the potential biological involvement of miRNA expression in the immune response and beta cell function in T1D. MethodsWe screened 377 serum miRNAs of 110 subjects divided into four groups: healthy individuals (control group) and patients at different stages of T1D progression, from the initial immunological manifestation presenting islet autoantibodies (AbP group) until partial and strong beta cell damage in the recent (recent T1D group) and long-term T1D, with 2 to 5 years of disease (T1D 2-5y group).Results The results revealed 69 differentially expressed miRNAs (DEMs) in relation to controls. Several miRNAs were correlated with islet autoantibodies (IA2A, GADA, and Znt8A), age, and C-peptide levels, mainly from AbP, and recent T1D groups pointing these miRNAs as relevant to T1D pathogenesis and progression. Several miRNAs were related to metabolic derangements, inflammatory pathways, and several other autoimmune diseases. Pathway analysis of putative DEM targets revealed an enrichment in pathways related to metabolic syndrome, inflammatory response, apoptosis and insulin signaling pathways, metabolic derangements, and decreased immunomodulation. One of the miRNAs' gene targets was DYRK2 (dual-specificity tyrosine-phosphorylation-regulated kinase 2), which is an autoantigen targeted by an antibody in T1D. ROC curve analysis showed hsa-miR-16 and hsa-miR-200a-3p with AUCs greater than for glucose levels, with discriminating power for T1D prediction greater than glucose levels. Conclusions/Interpretation. Our data suggests a potential influence of DEMs on disease progression from the initial autoimmune lesion up to severe beta cell dysfunction and the role of miRNAs hsa-miR-16 and hsa-miR-200a-3p as biomarkers of T1D progression.

Genetic regulation and variation of expression of miRNA and mRNA transcripts in fetal muscle tissue in the context of sex, dam and variable fetal weight

BackgroundImpaired skeletal muscle growth in utero can result in reduced birth weight and pathogenesis of intrauterine growth restriction. Fetal and placental growth is influenced by many factors including genetic, epigenetic and environmental factors. In fact, the sex and genotype of the fetus itself, as well as the mother providing it with a suitable environment, influence the growth of the fetus. Hence, our goal was to decipher and elucidate the molecular pathways of developmental processes mediated by miRNAs and mRNAs in fetal muscle tissue in the context of sex, dam, and fetal weight. Therefore, we analyse the variation of miRNA and mRNA expression in relation to these factors. In addition, the coincidence of genetic regulation of these mRNAs and miRNAs, as revealed by expression quantitative trait loci (eQTL) analyses, with sex-, mother- and weight-associated expression was investigated.MethodsA three-generation pig F2 population (n = 118) based on reciprocal crossing of German Landrace (DL) and Pietrain (Pi) was used. Genotype information and transcriptomic data (mRNA and miRNA) from longissimus dorsi muscle (LDM) of pig fetuses sampled at 63 days post-conception (dpc) were used for eQTL analyses.ResultsThe transcript abundances of 13, 853, and 275 probe-sets were influenced by sex, dam and fetal weight at 63 dpc, respectively (FDR < 5%). Most of significant transcripts affected by sex were located on the sex chromosomes including KDM6A and ANOS1 or autosomes including ANKS1B, LOC100155138 and miR-153. The fetal muscle transcripts associated with fetal weight indicated clearer metabolic directions than maternally influenced fetal muscle transcripts. Moreover, coincidence of genetic regulation (eQTL) and variation in transcript abundance due to sex, dam and fetal weight were identified.ConclusionsIntegrating information on eQTL, sex-, dam- and weight-associated differential expression and QTL for fetal weight allowed us to identify molecular pathways and shed light on the basic biological processes associated with differential muscle development in males and females, with implications for adaptive fetal programming.

Circulating miRNAs Are Associated with Inflammation Biomarkers in Children with Overweight and Obesity: Results of the I.Family Study.

Increasing data suggest that overnutrition-induced obesity may trigger an inflammatory process in adipose tissue and upturn in the innate immune system. Numerous players have been involved in governing the inflammatory response, including epigenetics. Among epigenetic players, miRNAs are emerging as crucial regulators of immune cell development, immune responses, autoimmunity, and inflammation. In this study, we aimed at identifying the involvement of candidate miRNAs in relation to inflammation-associated biomarkers in a subsample of European children with overweight and obesity participating in the I.Family study. The study sample included individuals with increased adiposity since this condition contributes to the early occurrence of chronic low-grade inflammation. We focused on the acute-phase reagent C-reactive protein (CRP) as the primary outcome and selected cytokines as plausible biomarkers of inflammation. We found that chronic low-grade CRP elevation shows a highly significant association with miR-26b-3p and hsa-miR-576-5p in boys. Furthermore, the association of CRP with hsa-miR-10b-5p and hsa-miR-31-5p is highly significant in girls. We also observed major sex-related associations of candidate miRNAs with selected cytokines. Except for IL-6, a significant association of hsa-miR-26b-3p and hsa-miR-576-5p with TNF-α, IL1-Ra, IL-8, and IL-15 levels was found exclusively in boys. The findings of this exploratory study suggest sex differences in the association of circulating miRNAs with inflammatory response biomarkers, and indicate a possible role of miRNAs among the candidate epigenetic mechanisms related to the process of low-grade inflammation in childhood obesity.

NAFLD and vitamin D: Evidence for intersection of microRNA-regulated pathways.

Non-alcoholic fatty liver disease (NAFLD) is now the most common cause of chronic liver disease, worldwide. The molecular pathogenesis of NAFLD is complex, involving numerous signalling molecules, including microRNAs (miRNAs). Dysregulation of miRNA expression is associated with hepatic inflammation, fibrosis and hepatocellular carcinoma. Although miRNAs are also critical to the cellular response to vitamin D, mediating regulation of the vitamin D receptor and vitamin D's anti-cancer effects, the role of vitamin-D-regulated miRNAs in NAFLD pathogenesis has been relatively unexplored. Therefore, this review aims to critically assess the evidence for a potential subset of miRNAs that are both dysregulated in NAFLD and modulated by vitamin D. Comprehensive review of eighty-nine human studies identified twenty-five miRNAs found dysregulated in more than one NAFLD study. In contrast, only seventeen studies, including a protocol for a trial in NAFLD, had examined miRNAs in relation to vitamin D status, response to supplementation, or vitamin D in the context of the liver. This paper summarises these data and reviews the biological roles of six miRNAs (miR-21, miR-30, miR-34, miR-122, miR-146, miR-200) found dysregulated in multiple independent NAFLD studies. While modulation of miRNAs by vitamin D has been understudied, integration of the data suggests seven vitamin-D-modulated miRNAs (miR-27, miR-125, miR-155, miR-192, miR-223, miR-375, miR-378) potentially relevant to NAFLD pathogenesis. Our summary tables provide a significant resource to underpin future hypothesis-driven research, and we conclude that the measurement of serum and hepatic miRNAs in response to vitamin D supplementation in larger trials is warranted.

Extracellular Vesicles and Their miRNA Content in Amniotic and Tracheal Fluids of Fetuses with Severe Congenital Diaphragmatic Hernia Undergoing Fetal Intervention.

Infants with congenital diaphragmatic hernia (CDH) are at high risk of postnatal mortality due to lung hypoplasia and arterial pulmonary hypertension. In severe cases, prenatal intervention by fetal endoscopic tracheal occlusion (FETO) can improve survival by accelerating lung growth. However, postnatal mortality remains in the range of about 50% despite fetal treatment, and there is currently no clear explanation for this different clinical response to FETO. We evaluated the concentration of extracellular vesicles (EVs) and associated microRNA expression in amniotic and tracheal fluids of fetuses with CDH undergoing FETO, and we examined the association between molecular findings and postnatal survival. We observed a higher count of EVs in the amniotic fluid of non-survivors and in the tracheal fluid sampled in utero at the time of reversal of tracheal occlusion, suggesting a pro-inflammatory lung reactivity that is already established in utero and that could be associated with a worse postnatal clinical course. In addition, we observed differential regulation of four EV-enclosed miRNAs (miR-379-5p, miR-889-3p; miR-223-3p; miR-503-5p) in relation to postnatal survival, with target genes possibly involved in altered lung development. Future research should investigate molecular therapeutic agents targeting differentially regulated miRNAs to normalize their expression and potentially improve clinical outcomes.