miR-744-5p contributes to ocular inflammation in patients with primary Sjogrens Syndrome

MiR-34a promotes mitochondrial pathway of apoptosis in human salivary gland epithelial cells by activating NF-κB signaling

To investigate the potential molecular mechanism of miR-34a in Sjögren's syndrome (SS). Transmission electron microscopy was used to observe the salivary gland tissues of mild and severe SS patients. SS mouse model was constructed and injected with miR-34a antagonist. HSGE cells were transfected with miR-34a mimic. Starbase predicted miR-34a binding sites and validated them with dual-luciferase reporter assays. Immunohistochemistry, HE staining, CCK-8, TUNEL assay, flow cytometry, immunofluorescence and Western Blot were used to investigate the effects of miR-34a on NF-κB signaling and mitochondrial pathway of apoptosis in HSGE cells. Severe SS patients showed obvious mitochondrial damage and apoptosis in salivary glands. MiR-34a was overexpressed and NF-κB signaling is activated in salivary glands of severe SS patients. Inhibition of miR-34a alleviated salivary gland injury in SS mice, as well as inhibited the activation of NF-κB signaling and mitochondrial pathway of apoptosis. In conclusion, miR-34a promoted NF-κB signaling by targeting IκBα, thereby causing mitochondrial pathway apoptosis and aggravating SS-induced salivary gland damage.

Role of ncRNAs in the Pathogenesis of Sjögren's Syndrome

Sjögren's syndrome is a multisystemic autoimmune disease that mainly affects the exocrine glands, causing dryness of the eyes and the mouth as the principal symptoms. Non-coding RNAs (ncRNAs), once regarded as genomic "junk", are now appreciated as important molecular regulators of gene expression, not least in Sjögren's syndrome and other autoimmune diseases. Here we review research into the causative roles of microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) on immunological responses, inflammation, and salivary gland epithelial cell function in Sjögren's syndrome patients. These ncRNAs represent promising new therapeutic targets for treating the disease and possibly as biomarkers for early diagnosis.

Chemokines and lymphocyte homing in Sjögren's syndrome

Sjögren's syndrome (SS) is a chronic systemic autoimmune disease that typically presents with lymphocyte, dendritic cell, and macrophage infiltration of exocrine gland ducts and the formation of ectopic germinal centers. The interactions of lymphocyte homing receptors and addressins and chemokines and their receptors, such as α4β7/MAdCAM-1, LFA-1/ICAM-1, CXCL13/CXCR5, CCL25/CCR9, CX3CL1/CX3CR1, play important roles in the migration of inflammatory cells to the focal glands and the promotion of ectopic germinal center formation in SS. A variety of molecules have been shown to be involved in lymphocyte homing, including tumor necrosis factor-α, interferon (IFN)-α, IFN-β, and B cell activating factor. This process mainly involves the Janus kinase-signal transducer and activator of transcription signaling pathway, lymphotoxin-β receptor pathway, and nuclear factor-κB signaling pathway. These findings have led to the development of antibodies to cell adhesion molecules, antagonists of chemokines and their receptors, compounds interfering with chemokine receptor signaling, and gene therapies targeting chemokines and their receptors, providing new targets for the treatment of SS in humans. The aim of this study was to explore the relationship between lymphocyte homing and the pathogenesis of SS, and to provide a review of recent studies addressing lymphocyte homing in targeted therapy for SS.

Significance of N6-methyladenosine RNA methylation regulators in diagnosis and subtype classification of primary Sjögren's syndrome

The importance of N6-methyladenine (m6A) in mRNA metabolism, physiology, pathology and other life processes is well recognized. However, the exact role of m6A regulators in primary Sjögren's syndrome (PSS) remains unclear. In this study, we used bioinformatics and machine learning random forest approach to screen eight key m6A regulators from the Gene Expression Omnibus GSE7451, GSE40611 and GSE84844 datasets. An accurate nomogram model for predicting PSS risk was established based on these regulators. And using consensus clustering, patients diagnosed with PSS were classified into two different m6A patterns. We found that patients in group B had higher m6A scores compared to those in group A: furthermore, both groups were closely related to immunity and possibly to other diseases. These results emphasise the important role of m6A regulators in the pathogenesis of PSS. Our study of m6A patterns may inform future immunotherapy strategies for PSS.

Epigenetic mechanisms of non-retinal components of the aging eye and novel therapeutic strategies

The eye is a complex organ composed of various cell types, each serving a unique purpose. However, aging brings about structural and functional changes in these cells, leading to discomfort and potential pathology. Alterations in gene expression, influenced by aging and environmental factors, significantly affect cell structure and function. Epigenetics, a field focused on understanding the correlation between changes in gene expression, cell function, and environmental factors, plays a crucial role in unraveling the molecular events responsible for age-related eye changes. This prompts the possibility of developing epigenetic strategies to intervene in these changes or reinstate proper molecular activities. Indeed, research has demonstrated that epigenetic modifications, including DNA methylation, histone modification, and non-coding RNAs, are closely associated with age-related alterations in gene expression and cell function. This review aims to compile and synthesize the most recent body of evidence supporting the role of epigenetics in age-related alterations observed in various components of the eye. Specifically, it focuses on the impact of epigenetic changes in the ocular surface, tear film, aqueous humor, vitreous humor, and lens. Furthermore, it highlights the significant advancements that have been made in the field of epigenetic-based experimental therapies, specifically focusing on their potential for treating pathological conditions in the aging eye.

MicroRNA-146a negatively regulates inflammation via the IRAK1/TRAF6/NF-κB signaling pathway in dry eye

Inflammation is a key factor in the pathogenesis of dry eye disease (DED). We aimed to investigate the role of microRNA-146a (miR-146a) in regulating corneal inflammation in a mouse model of benzalkonium chloride (BAC)-induced dry eye and the TNF-α-induced NF-κB signaling pathway in human corneal epithelial cells (HCECs). A mouse model of dry eye was established by administering with BAC to BALB/c mice, and the expression of TNF-α, IL-1β, IL-6, IL-8, cyclooxygenase 2 (COX2), interleukin-1 receptor-associated kinase 1 (IRAK1) and TNF receptor-associated factor 6 (TRAF6) in the corneas of dry eye model mice was significantly increased; this was accompanied by the upregulation of miR-146a and activation of the NF-κB pathway. In vitro, TNF-α induced miR-146a expression in HCECs, while the NF-κB inhibitor SC-514 reduced the expression of miR-146a. Overexpression of miR-146a decreased the expression of IRAK1 and TRAF6, which have been identified as targets of miR-146a. Furthermore, overexpression of miR-146a suppressed NF-κB p65 translocation from the cytoplasm to the nucleus. Moreover, overexpression of miR-146a attenuated the TNF-α-induced expression of IL-6, IL-8, COX2 and intercellular adhesion molecule 1 (ICAM1), while inhibition of miR-146a exerted the opposite effect. Our results suggest that miR-146a mediates the inflammatory response in DED. MiR-146a negatively regulates inflammation in HCECs through the IRAK1/TRAF6/NF-κB pathway, and this may serve as a potential therapeutic approach for the treatment of DED.

Oxidative Stress and Epigenetics: miRNA Involvement in Rare Autoimmune Diseases

Autoimmune diseases (ADs) such as Sjögren’s syndrome, Kawasaki disease, and systemic sclerosis are characterized by chronic inflammation, oxidative stress, and autoantibodies, which cause joint tissue damage, vascular injury, fibrosis, and debilitation. Epigenetics participate in immune cell proliferation and differentiation, which regulates the development and function of the immune system, and ultimately interacts with other tissues. Indeed, overlapping of certain clinical features between ADs indicate that numerous immunologic-related mechanisms may directly participate in the onset and progression of these diseases. Despite the increasing number of studies that have attempted to elucidate the relationship between miRNAs and oxidative stress, autoimmune disorders and oxidative stress, and inflammation and miRNAs, an overall picture of the complex regulation of these three actors in the pathogenesis of ADs has yet to be formed. This review aims to shed light from a critical perspective on the key AD-related mechanisms by explaining the intricate regulatory ROS/miRNA/inflammation axis and the phenotypic features of these rare autoimmune diseases. The inflamma-miRs miR-155 and miR-146, and the redox-sensitive miR miR-223 have relevant roles in the inflammatory response and antioxidant system regulation of these diseases. ADs are characterized by clinical heterogeneity, which impedes early diagnosis and effective personalized treatment. Redox-sensitive miRNAs and inflamma-miRs can help improve personalized medicine in these complex and heterogeneous diseases.

Investigation of Relationship Between Small Noncoding RNA (sncRNA) Expression Levels and Serum Iron, Copper, and Zinc Levels in Clinical Diagnosed Multiple Sclerosis Patients

In our study, we aimed to investigate the relationship between microRNA (miRNA) expression levels and serum iron (Fe), copper (Cu), and zinc (Zn) levels in Multiple sclerosis (MS) patients. Total RNA was isolated from peripheral venous blood containing ethylenediaminetetraacetic acid (EDTA) of MS patients and controls. Total RNA was labeled with Cy3-CTP fluorescent dye. Hybridization of samples was performed on microarray slides and arrays were scanned. Data argument and bioinformatics analysis were performed. Atomic absorption spectrophotometer method was used to measure serum Fe, Cu, and Zn levels. In our study, in bioinformatics analysis, although differently expressed miRNAs were not detected between 16 MS patients and 16 controls, hsa-miR-744-5p upregulation was detected between 4 MS patients and 4 controls. This may be stem from the patient group consisting of MS patients who have never had an attack for 1 year. Serum iron levels were detected significantly higher in the 16 MS patients compared to the 16 controls. This may be stem from the increase in iron accumulation based on inflammation in MS disease. According to the findings in our study, hsa-miR-744-5p upregulation has been determined as an early diagnostic biomarker for the development together of insulin resistance, diabetes mellitus associated with insulin signaling, and Alzheimer's diseases. Therefore, hsa-miR-744-5p is recommended as an important biomarker for the development together of diabetes mellitus, Alzheimer's disease, and MS disease. In addition, increased serum Fe levels may be suggested as an important biomarker for neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, and MS disease.

MicroRNAs in T Cell-Immunotherapy

MicroRNAs (miRNAs) act as master regulators of gene expression in homeostasis and disease. Despite the rapidly growing body of evidence on the theranostic potential of restoring miRNA levels in pre-clinical models, the translation into clinics remains limited. Here, we review the current knowledge of miRNAs as T-cell targeting immunotherapeutic tools, and we offer an overview of the recent advances in miRNA delivery strategies, clinical trials and future perspectives in RNA interference technologies.

The Emerging Roles of Pellino Family in Pattern Recognition Receptor Signaling

The Pellino family is a novel and well-conserved E3 ubiquitin ligase family and consists of Pellino1, Pellino2, and Pellino3. Each family member exhibits a highly conserved structure providing ubiquitin ligase activity without abrogating cell and structure-specific function. In this review, we mainly summarized the crucial roles of the Pellino family in pattern recognition receptor-related signaling pathways: IL-1R signaling, Toll-like signaling, NOD-like signaling, T-cell and B-cell signaling, and cell death-related TNFR signaling. We also summarized the current information of the Pellino family in tumorigenesis, microRNAs, and other phenotypes. Finally, we discussed the outstanding questions of the Pellino family in immunity.

Aquaporin5-Targeted Treatment for Dry Eye Through Bioactive Compounds and Gut Microbiota

Dry eye and dry mouth are the principal sources of morbidity for patients with Sjögren's syndrome (SS). There are few effective treatments, particularly systemic ones. Targeting aquaprin-5 (AQP5)-mediated tear secretion has been tested as a novel ancillary strategy and has proved promising. Patients have a great interest in using complementary medicine, including nutraceuticals and bioactive compounds to alleviate their symptoms. Potential mechanisms by which phytocompounds and bioactive compounds may benefit SS ocular and mouth symptoms through modulation of AQP5 activity are presented within this review. Supplementation with prebiotics (such as polyphenols with high bioavailability) in SS patients with lower Firmicutes/Bacteroides (F/B) community ratio phenotype, through administration of butyrate-producing diets, is proposed as ancillary strategy for dry eye and mouth. The potential use of natural bioactive compounds to treat dry eye could also apply to dry mouth occurring in the context of aging and SS. This novel hypothesis could have implications with respect to planning a successful dietary regimen for achieving and maintaining a normal gut microbiota in SS patients. This regimen would include augmenting butyrate-producing foodstuffs and/or polyphenol-rich syrups, and high amounts of some specific probiotic-rich foodstuffs such as yogurt, soy yogurt, or as probiotic supplements. There are applications for pharmaceutical and nutraceutical products aiming to relieve dry eye and mouth.

Integrated mRNA-seq and miRNA-seq analysis of goat fibroblasts response to Brucella Melitensis strain M5-90

Brucellosis is a globally zoonotic bacterial disease of humans and various animals including goats, sheep, and cattle. Brucella melitensis M5-90, a live attenuated vaccine strain, has been widely used to prevent brucellosis in goats and sheep. However, the molecular mechanisms governing protective immunity response in non-professional phagocytes infected with B. melitensis M5-90 have not been fully investigated, especially in goats. In our research, goat fibroblasts were used as in vitro models to determine these mechanisms by transcriptome analysis. After incubating with B. melitensis M5-90 3 h, the infected goat fibroblasts were collected at 0 h, 4 h, 24 h, 48 h and 72 h for RNA-seq. The results indicated that there were totally 11,819 differentially expressed genes (DEGs) and 777 differentially expressed (DE) miRNAs found in experiment groups compared with the control groups (|log2(Foldchange)|≥1, FDR<0.05). GO and KEGG enrichment analyses revealed that down-regulated genes were involved in the riboflavin metabolism and positive regulation of IL-8 secretion pathway. The up-regulated genes were mainly involved in adaptive immunity, including TNF signaling pathway, MAPK signaling pathway and JAK/STAT pathway. Additionally, cytokine-cytokine receptor interaction, natural killer cell mediated cytotoxicity and toll-like receptor signaling pathway, which associated with innate immunity pathways, were also induced. Based on the Pearson correlation coefficients and prediction results of TargetScan and miRanda, the miRNA-mRNA networks of NFKB1, IFNAR2 and IL10RB were constructed and verified in goat fibroblasts by qPCR, which demonstrated that goat fibroblasts displayed immunomodulatory properties. Our findings provide a deeper insight into the host miRNA-driven B. melitensis defense mechanism and reveal the transcriptome changes involved in the innate and adaptive immune response of the goats to B. melitensis infection.

Emerging Role of microRNAs and Long Non-Coding RNAs in Sjögren's Syndrome

Sjögren’s Syndrome (SS) is a chronic autoimmune inflammatory disease. It is considered a multifactorial pathology, in which underlying genetic predisposition, epigenetic mechanisms and environmental factors contribute to development. The epigenetic regulations represent a link between genetic predisposition and environmental factors. Recent studies suggested a regulatory role for non-coding RNAs in critical biological and disease processes. Among non-coding RNAs, microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) play a critical role in the post-transcriptional mRNA expression, forming a complex network of gene expression regulation. This review aims to give an overview of the latest studies that have investigated the role of miRNAs and lncRNAs in the SS. We included papers that investigated the expression of non-coding RNAs on different tissues, in particular on peripheral blood mononuclear cells and salivary glands. However, regarding the involvement of non-coding RNAs genetic variability in SS susceptibility very few data are available. Further research could help to elucidate underlying pathogenic processes of SS and provide new opportunities for the development of targeted therapies.

Comprehensive Analysis of Correlations in the Expression of miRNA Genes and Immune Checkpoint Genes in Bladder Cancer Cells

Personalised medicine is the future and hope for many patients, including those with cancers. Early detection, as well as rapid, well-selected treatment, are key factors leading to a good prognosis. MicroRNA mediated gene regulation is a promising area of development for new diagnostic and therapeutic methods, crucial for better prospects for patients. Bladder cancer is a frequent neoplasm, with high lethality and lacking modern, advanced therapeutic modalities, such as immunotherapy. MicroRNAs are involved in bladder cancer pathogenesis, proliferation, control and response to treatment, which we summarise in this perspective in response to lack of recent review publications in this field. We further performed a correlation-based analysis of microRNA and gene expression data in bladder cancer (BLCA) TCGA dataset. We identified 27 microRNAs hits with opposite expression profiles to genes involved in immune response in bladder cancer, and 24 microRNAs hits with similar expression profiles. We discuss previous studies linking the functions of these microRNAs to bladder cancer and assess if they are good candidates for personalised medicine therapeutics and diagnostics. The discussed functions include regulation of gene expression, interplay with transcription factors, response to treatment, apoptosis, cell proliferation and angiogenesis, initiation and development of cancer, genome instability and tumour-associated inflammatory reaction.