miR-708-5p promotes fibroblast-like synoviocytes' cell apoptosis and ameliorates rheumatoid arthritis by the inhibition of Wnt3a/β-catenin pathway

Advances in RNA therapy for the treatment of autoimmune diseases

Autoimmune diseases (ADs) are a group of complex, chronic conditions characterized by disturbance of immune tolerance, with examples including systemic lupus erythematosus, rheumatoid arthritis, multiple sclerosis, and psoriasis. These diseases have unclear pathogenesis, and traditional therapeutic approaches remain limited. However, advances in high-throughput histology technology and scientific discoveries have led to the identification of various pathogenic factors contributing to ADs. Coupled with improvements in RNA nucleic acid-based drug synthesis, design, and delivery, RNA-based therapies have been extensively investigated for their potential in treating ADs. This paper reviews the progress in the use of miRNAs, lncRNAs, circRNAs, siRNAs, antisense oligonucleotides (ASOs), aptamers, mRNAs, and other RNA-based therapies in ADs, focusing on their therapeutic potential and application prospects, providing insights for future research and clinical treatment of autoimmune diseases.

Wnt signaling as a translational target in rheumatoid and psoriatic arthritis

BACKGROUND

Rheumatoid arthritis (RA) and Psoriatic arthritis (PsA) are chronic inflammatory diseases mainly affecting joints. RA primarily targets the synovial joints and is characterized by cartilage and bone erosion, whereas PsA is associated with skin and nail psoriasis and is characterized by erosive bone damage with an exuberant bone formation and soft tissue involvement. Recent evidence described the involvement of the Wnt pathway in the pathogenesis of these diseases. Thus, we aimed to analyze some components of Wnt signaling, i.e. DKK1, Wnt 5a and β-catenin, and their association with disease activity indices, investigating possible differences between the two diseases.

METHODS

Sera from 18 RA patients naïve for biological therapy, 18 PsA patients and 20 matched healthy donors (HD) were tested for DKK1 by ELISA, Wnt 5a and β-catenin by Immunoblotting. Values were correlated with CTX-1, detected by ELISA, and with disease activity indices: Disease Activity Score on 28 joints (DAS28-CRP) for RA and the Disease Activity in Psoriatic Arthritis (DAPSA) score for PsA.

RESULTS

This study highlights significant increase in DKK1, Wnt 5a, and β-catenin levels in RA and PsA patients compared to HD, with distinct patterns of correlation with disease activity indices. Indeed, in RA patients, DKK1 levels positively correlated with DAS28-CRP score, whereas in PsA patients, DKK1 levels negatively correlated with DAPSA score. Our findings showed a strong correlation between DKK1 and CTX-1 levels in RA patients, supporting the relationship between DKK1 levels and the presence of joint erosions. Furthermore, a significant positive correlation was found between β-catenin and IL-6 levels in RA, indicating that β-catenin may be involved in the inflammatory cascade.

CONCLUSION

This study compares the involvement of Wnt signaling in RA and PsA, suggesting that Wnt signaling may represent a possible mechanism of disease activity. In particular, it indicates that DKK1 levels are correlated with CTX-1, a marker of bone resorption, and with disease activity in RA patients. These findings underscore the importance of these biomarkers in the potential monitoring of patients, offering insights into disease mechanisms and potential therapeutic targets.

MiR-378 exaggerates angiogenesis and bone erosion in collagen-induced arthritis mice by regulating endoplasmic reticulum stress

Rheumatoid arthritis (RA) is a chronic autoimmune disorder marked by pain, inflammation, and discomfort in the synovial joints. It is critical to understand the pathological mechanisms of RA progression. MicroRNA-378 (miR-378) is highly expressed in the synovium of RA patients and positively correlated with disease severity, but its function and underlying mechanisms remain poorly understood. In this study, miR-378 transgenic (miR-378high) mice were used to construct the collagen-induced arthritis (CIA) model for exploring the role of miR-378 in RA development. miR-378high CIA mice showed accelerated RA development, as evidenced by exaggerated joint swelling and bone structural deformities. More severe endoplasmic reticulum (ER) stress and the consequent angiogenesis and osteoclastogenesis were also activated in the synovial tissue and calcaneus, respectively, in the miR-378high group, suggesting that ER plays a significant role in miR-378-mediated RA pathogenesis. Upon in vitro RA induction, fibroblast-like synoviocytes (FLSs) isolated from miR-378high mice showed a higher expression level of ER stress markers. The conditioned medium (CM) from RA-FLSs of miR-378high mice stimulated more intensive angiogenesis and osteoclastogenesis. The ER stress-related protein Crebrf was identified as a downstream target of miR-378. Crebrf knockdown diminished the promoting effect of miR-378 on ER stress, as well as its downstream angiogenesis and osteoclastogenesis activities. Tail vein injection of anti-miR-378 lentivirus in an established RA mouse model was shown to ameliorate RA progression. In conclusion, miR-378 amplified RA development by promoting ER stress and downstream angiogenesis and osteoclastogenesis, thus indicating that miR-378 may be a potential therapeutic target for RA treatment.

Small molecule and big function: MicroRNA-mediated apoptosis in rheumatoid arthritis

Rheumatoid arthritis (RA) is a common autoimmune condition and chronic inflammatory disease, mostly affecting synovial joints. The complex pathogenesis of RA is supportive of high morbidity, disability, and mortality rates. Pathological changes a common characteristic in RA synovial tissue is attributed to the inadequacy of apoptotic pathways. In that regard, apoptotic pathways have been the center of attention in RA therapeutic approaches. As the regulators in the complex network of apoptosis, microRNAs (miRNAs) are found to be vital modulators in both intrinsic and extrinsic pathways through altering their regulatory genes. Indeed, miRNA, a member of the family of non-coding RNAs, are found to be an important player in not even apoptosis, but proliferation, gene expression, signaling pathways, and angiogenesis. Aberrant expression of miRNAs is implicated in attenuation and/or intensification of various apoptosis routes, resulting in culmination of human diseases including RA. Considering the need for more studies focused on the underlying mechanisms of RA in order to elevate the unsatisfactory clinical treatments, this study is aimed to delineate the importance of apoptosis in the pathophysiology of this disease. As well, this review is focused on the critical role of miRNAs in inducing or inhibiting apoptosis of RA-synovial fibroblasts and fibroblast-like synoviocytes and how this mechanism can be exerted for therapeutic purposes for RA.

miR-708-5p deficiency involves the degeneration of mandibular condylar chondrocytes via the TLR4/NF-κB pathway

OBJECTIVE

Ageing and aberrant biomechanical stimulation are two major risk factors for osteoarthritis (OA). One of the main characteristics of aged cartilage is cellular senescence. One of the main characteristics of osteoarthritic joints is cartilage degeneration. The cells in the temporomandibular joint (TMJ) cartilage are zonally arranged. The deep zone cells are differentiated from the superficial zone cells (SZCs). The purpose of the present study was to investigate whether degenerative shear stress (SS) stimulates the senescence programme in TMJ SZCs, and to determine which miRNA is involved in this process.

METHOD

SZCs were isolated from the TMJ condyles of 3-week-old rats and treated with continuous passaging or SS. RNA sequencing was conducted to identify miRNA(s) that overlap with those involved in the replication senescence process and the SS-induced degeneration programme. Unilateral anterior crossbite (UAC), which is TMJ-OA inducible, was applied to 2-month-old and 12-month-old mice for 3 weeks. The effect of TMJ local injection of agomiR-708-5p was evaluated histologically.

RESULTS

Both replication and SS treatment induced SZC senescence. miR-708-5p was identified. Knocking down miR-708-5p in SS-treated SZCs led to more severe senescence by alleviating the inhibitory impact of miR-708-5p on the TLR4/NF-κB pathway. miR-708-5p expression in mouse TMJ cartilage decreased with age. UAC induced more severe osteoarthritic cartilage lesions in 12-month-old mice than in 2-month-old mice. Injection of agomiR-708-5p suppressed UAC-induced osteoarthritic cartilage lesions.

CONCLUSIONS

Age-related miR-708-5p deficiency is involved in the mechanically stimulated OA process. Intra-articular administration of agomiR-708-5p is a promising new strategy for OA treatment.

Role of MicroRNAs in Inflammatory Joint Diseases: A Review

Inflammatory arthritis commonly initiates in the soft tissues lining the joint. This lining swells, as do the cells in it and inside the joint fluid, producing chemicals that induce inflammation signs such as heat, redness, and swelling. MicroRNA (miRNA), a subset of non-coding small RNA molecules, post-transcriptionally controls gene expression by targeting their messenger RNA. MiRNAs modulate approximately 1/3 of the human genome with their multiple targets. Recently, they have been extensively studied as key modulators of the innate and adaptive immune systems in diseases such as allergic disorders, types of cancer, and cardiovascular diseases. However, research on the different inflammatory joint diseases, such as rheumatoid arthritis, gout, Lyme disease, ankylosing spondylitis, and psoriatic arthritis, remains in its infancy. This review presents a deeper understanding of miRNA biogenesis and the functions of miRNAs in modulating the immune and inflammatory responses in the above-mentioned inflammatory joint diseases. According to the literature, it has been demonstrated that the development of inflammatory joint disorders is closely related to different miRNAs and their specific regulatory mechanisms. Furthermore, they may present as possible prognostic and diagnostic biomarkers for all diseases and may help in developing a therapeutic response. However, further studies are needed to determine whether manipulating miRNAs can influence the development and progression of inflammatory joint disorders.

Exosomal Osteoclast-Derived miRNA in Rheumatoid Arthritis: From Their Pathogenesis in Bone Erosion to New Therapeutic Approaches

Rheumatoid arthritis (RA) is an autoimmune disease that causes inflammation, pain, and ultimately, bone erosion of the joints. The causes of this disease are multifactorial, including genetic factors, such as the presence of the human leukocyte antigen (HLA)-DRB1*04 variant, alterations in the microbiota, or immune factors including increased cytotoxic T lymphocytes (CTLs), neutrophils, or elevated M1 macrophages which, taken together, produce high levels of pro-inflammatory cytokines. In this review, we focused on the function exerted by osteoclasts on osteoblasts and other osteoclasts by means of the release of exosomal microRNAs (miRNAs). Based on a thorough revision, we classified these molecules into three categories according to their function: osteoclast inhibitors (miR-23a, miR-29b, and miR-214), osteoblast inhibitors (miR-22-3p, miR-26a, miR-27a, miR-29a, miR-125b, and miR-146a), and osteoblast enhancers (miR-20a, miR-34a, miR-96, miR-106a, miR-142, miR-199a, miR-324, and miR-486b). Finally, we analyzed potential therapeutic targets of these exosomal miRNAs, such as the use of antagomiRs, blockmiRs, agomiRs and competitive endogenous RNAs (ceRNAs), which are already being tested in murine and ex vivo models of RA. These strategies might have an important role in reestablishing the regulation of osteoclast and osteoblast differentiation making progress in the development of personalized medicine.

Non-coding RNAs involved in fibroblast-like synoviocyte functioning in arthritis rheumatoid: From pathogenesis to therapy

Rheumatoid arthritis (RA) is a polygenic autoimmune disorder with an uncertain etiology, primarily impacting the joints. Moreover, the disease may manifest beyond articular involvement, leading to extra-articular manifestations. Fibroblast-like synoviocytes (FLS) are cells of mesenchymal origin that possess crucial physiological significance within the synovium, contributing to the synthesis of specific constituents found in the synovial fluid and articular cartilage. Consequently, there has been a growing focus on FLS as a potential therapeutic target in the context of RA. Recent investigations have revealed that non-coding RNAs (ncRNAs) serve as pivotal regulators of FLS function, with their dysregulated expression patterns being detected within FLS populations. NcRNAs, such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), assume essential functions as regulators of gene expression at both the post-transcriptional and transcriptional levels, and also serve as guiding molecules for chromatin-modifying complexes. Majority of these ncRNAs contribute to various FLS activities including metastasis, proliferation, and cytokine production. In the current work, we comprehensively review the existing literature on ncRNAs, which play pivotal roles in FLS activity and the pathogenesis of RA. Furthermore, this study provides a comprehensive summary and description of the lncRNA/circRNA-miRNA-mRNA regulatory axes in FLS activity, along with potential implications for the RA development. As well, in the final section, we illustrated that therapeutic agents including herbal medicine, and exosomes by modulating ncRNAs regulate FLS activity.

Study on Potential Differentially Expressed Genes in Idiopathic Pulmonary Fibrosis by Bioinformatics and Next-Generation Sequencing Data Analysis

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease with reduced quality of life and earlier mortality, but its pathogenesis and key genes are still unclear. In this investigation, bioinformatics was used to deeply analyze the pathogenesis of IPF and related key genes, so as to investigate the potential molecular pathogenesis of IPF and provide guidance for clinical treatment. Next-generation sequencing dataset GSE213001 was obtained from Gene Expression Omnibus (GEO), and the differentially expressed genes (DEGs) were identified between IPF and normal control group. The DEGs between IPF and normal control group were screened with the DESeq2 package of R language. The Gene Ontology (GO) and REACTOME pathway enrichment analyses of the DEGs were performed. Using the g:Profiler, the function and pathway enrichment analyses of DEGs were performed. Then, a protein-protein interaction (PPI) network was constructed via the Integrated Interactions Database (IID) database. Cytoscape with Network Analyzer was used to identify the hub genes. miRNet and NetworkAnalyst databaseswereused to construct the targeted microRNAs (miRNAs), transcription factors (TFs), and small drug molecules. Finally, receiver operating characteristic (ROC) curve analysis was used to validate the hub genes. A total of 958 DEGs were screened out in this study, including 479 up regulated genes and 479 down regulated genes. Most of the DEGs were significantly enriched in response to stimulus, GPCR ligand binding, microtubule-based process, and defective GALNT3 causes HFTC. In combination with the results of the PPI network, miRNA-hub gene regulatory network and TF-hub gene regulatory network, hub genes including LRRK2, BMI1, EBP, MNDA, KBTBD7, KRT15, OTX1, TEKT4, SPAG8, and EFHC2 were selected. Cyclothiazide and rotigotinethe are predicted small drug molecules for IPF treatment. Our findings will contribute to identification of potential biomarkers and novel strategies for the treatment of IPF, and provide a novel strategy for clinical therapy.

Role of miRNAs in Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease characterized by autoimmunity, synovial inflammation and joint destruction. Pannus formation in the synovial cavity can cause irreversible damage to the joint and cartilage and eventually permanent disability. Current conventional treatments for RA have limitations regarding efficacy, safety and cost. microRNA (miRNA) is a type of non-coding RNA (ncRNA) that regulates gene expression at the post-transcriptional level. The dysregulation of miRNA has been observed in RA patients and implicated in the pathogenesis of RA. miRNAs have emerged as potential biomarkers or therapeutic agents. In this review, we explore the role of miRNAs in various aspects of RA pathophysiology, including immune cell imbalance, the proliferation and invasion of fibroblast-like synovial (FLS) cell, the dysregulation of inflammatory signaling and disturbance in angiogenesis. We delve into the regulatory effects of miRNAs on Treg/Th17 and M1/M2 polarization, the activation of the NF-κB/NLRP3 signaling pathway, neovascular formation, energy metabolism induced by FLS-cell-induced energy metabolism, apoptosis, osteogenesis and mobility. These findings shed light on the potential applications of miRNAs as diagnostic or therapeutic biomarkers for RA management. Furthermore, there are some strategies to regulate miRNA expression levels by utilizing miRNA mimics or exosomes and to hinder miRNA activity via competitive endogenous RNA (ceRNA) network-based antagonists. We conclude that miRNAs offer a promising avenue for RA therapy with unlimited potential.

The functions and networks of non-coding RNAs in the pathogenesis of Rheumatoid Arthritis

Rheumatoid Arthritis (RA) is a chronic autoimmune disease. Its main feature is inflammation of synovial tissue with irreversible joint damage and severe physical damage. Non-coding RNAs (ncRNAs) are a class of RNAs that do not have the ability to encode proteins but are vital regulators that mediate many fundamental cellular processes and play an essential role in the pathogenesis of RA. Multiple verified ncRNAs have been confirmed as a prospective biomarkers for diagnosing and treating RA. In this paper, we aim to sort out the role of ncRNAs in the pathogenesis of RA and provide new ideas for the diagnosis and treatment of RA.

Rheumatoid arthritis and non-coding RNAs; how to trigger inflammation

Rheumatoid arthritis (RA) is a systemic and chronic inflammatory disease categorized by continuous synovitis in the joints and systemic inflammatory responses that can cause lifelong disability. The major cause of RA is the dysregulation of the immune response. The development of RA disease includes multiplex association of several interleukins and cells, which leads to synovial cell growth, cartilage and bone damage. The primary stage of RA disease is related to the modification of both the innate and adaptive immune systems, which leads to the formation of autoantibodies. This process results in many damaged molecules and epitope spreading. Both the innate (e.g., dendritic cells, macrophages, and neutrophils) and acquired immune cells (e.g., T and B lymphocytes) will increase and continue the chronic inflammatory condition in the next stages of the RA disease. In recent years, non-coding RNAs have been proved as significant controllers of biological functions, especially immune cell expansion and reactions. Non-coding RNAs were primarily containing microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA). Various studies confirmed non-coding RNAs as hopeful markers for diagnosing and curing RA. This review will describe and cover existing knowledge about RA pathogenesis, which might be favorable for discovering possible ncRNA markers for RA.

Comprehensive overview of microRNA function in rheumatoid arthritis

MicroRNAs (miRNAs), a class of endogenous single-stranded short noncoding RNAs, have emerged as vital epigenetic regulators of both pathological and physiological processes in animals. They direct fundamental cellular pathways and processes by fine-tuning the expression of multiple genes at the posttranscriptional level. Growing evidence suggests that miRNAs are implicated in the onset and development of rheumatoid arthritis (RA). RA is a chronic inflammatory disease that mainly affects synovial joints. This common autoimmune disorder is characterized by a complex and multifaceted pathogenesis, and its morbidity, disability and mortality rates remain consistently high. More in-depth insights into the underlying mechanisms of RA are required to address unmet clinical needs and optimize treatment. Herein, we comprehensively review the deregulated miRNAs and impaired cellular functions in RA to shed light on several aspects of RA pathogenesis, with a focus on excessive inflammation, synovial hyperplasia and progressive joint damage. This review also provides promising targets for innovative therapies of RA. In addition, we discuss the regulatory roles and clinical potential of extracellular miRNAs in RA, highlighting their prospective applications as diagnostic and predictive biomarkers.

The Double Face of miR-708: A Pan-Cancer Player with Dissociative Identity Disorder

Over the last decades, accumulating evidence has shown tumor-dependent profiles of miR-708, being either up- or downregulated, and thus, acting as a "Janus" regulator of oncogenic pathways. Herein, its functional duality was assessed through a thorough review of the literature and further validation in silico using The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. In the literature, miR-708 was found with an oncogenic role in eight tumor types, while a suppressor tumor role was described in seven cancers. This double profile was also found in TCGA and GEO databases, with some tumor types having a high expression of miR-708 and others with low expression compared with non-tumor counterparts. The investigation of validated targets using miRBase, miRTarBase, and miRecords platforms, identified a total of 572 genes that appeared enriched for PI3K-Akt signaling, followed by cell cycle control, p53, Apellin and Hippo signaling, endocrine resistance, focal adhesion, and cell senescence regulations, which are all recognized contributors of tumoral phenotypes. Among these targets, a set of 15 genes shared by at least two platforms was identified, most of which have important roles in cancer cells that influence either tumor suppression or progression. In a clinical scenario, miR-708 has shown to be a good diagnostic and prognosis marker. However, its multitarget nature and opposing roles in diverse human tumors, aligned with insufficient experimental data and the lack of proper delivery strategies, hamper its potential as a sequence-directed therapeutic.

MiR-708-5p/Pit-1 axis mediates high phosphate-induced calcification in vascular smooth muscle cells via Wnt8b/β-catenin pathway

Recently, the underlying mechanism of vascular calcification (VC) has been partially elucidated. However, it is still high incidence, and no effective treatment has been found. This study aims at figuring out the underlying mechanisms of microRNA-708-5p (miR-708-5p)/sodium-phosphate transporter 1 (Pit-1) axis in high phosphate (HP)-induced VC of T/G HA-VSMCs. Alizarin Red S staining was used to evaluate calcium salt deposition, and the activity of alkaline phosphatase (ALP) was determined by measuring the absorbance at 405 nm. RT-qPCR and Western blot were performed to assess the levels of miR-708-5p and Pit-1, the levels of ALP, Pit-1, β-catenin, glycogen synthesis kinase 3 β (GSK3β), and p-GSK3β proteins, respectively. The interaction between miR-708-5p and Pit-1 was validated by luciferase reporter assay. Our findings illustrated that miR-708-5p was downregulated and Pit-1was upregulated in HP-induced VC. MiR-708-5p mimics inhibited HP-induced VC. Further experiments demonstrated that miR-708-5p targets Pit-1. In addition, miR-708-5p inactivates the Wnt8b/β-catenin pathway via targeting Pit-1 to reduce HP-induced VC. MiR-708-5p has a crucial effect on VC via targeting Pit-1 and inhibiting Wnt8b/β-catenin pathway, it may serve as a new target for VC treatment.

MicroRNA Expression in Pseudoexfoliation Syndrome with the Use of Next-Generation Sequencing

Pseudoexfoliation syndrome (PEX) is a clinically important and biologically intriguing systemic disorder of the extracellular matrix. PEX etiopathogenesis was proved to be connected to multiple genes and other factors. However, the exact etiopathogenesis remains unknown. The aim of this study was to analyze miR expression in PEX using next-generation sequencing. An attempt was made to find the most commonly occurring miR in PEX, to evaluate miR that may have an essential role in the etiology of PEX syndrome. In addition, the correlation between the selected miRs’ expressions and age was investigated. Anterior lens capsules were obtained during cataract surgery. Next-generation sequencing was conducted on Illumina MiSeq. The average age was 68.2 years (with standard deviation +/− 6.92 years). Ten miRs with the highest level of expression represent approx. 95% of all readings. Four miRs with statistically significant differences in expression between groups have been distinguished: miR-671-3p, miR374a-5p, miR-1307-5p and miR-708-5p. The relationship between the most frequent miRs’ expressions and age has been evaluated and no correlation has been detected. In view of the above, it seems reasonable to examine the influence of miR on the biogenesis of PEX. Further studies on miR-671-3p, miR-374a-5p, miR-1307-5p and miR-708-5p expression in PEX are needed.

MicroRNA-Mediated Epigenetic Regulation of Rheumatoid Arthritis Susceptibility and Pathogenesis

MicroRNAs (miRNAs) play crucial roles in regulating the transcriptome and development of rheumatoid arthritis (RA). Currently, a comprehensive map illustrating how miRNAs regulate transcripts, pathways, immune system differentiation, and their interactions with terminal cells such as fibroblast-like synoviocytes (FLS), immune-cells, osteoblasts, and osteoclasts are still laking. In this review, we summarize the roles of miRNAs in the susceptibility, pathogenesis, diagnosis, therapeutic intervention, and prognosis of RA. Numerous miRNAs are abnormally expressed in cells involved in RA and regulate target genes and pathways, including NF-κB, Fas-FasL, JAK-STAT, and mTOR pathways. We outline how functional genetic variants of miR-499 and miR-146a partly explain susceptibility to RA. By regulating gene expression, miRNAs affect T cell differentiation into diverse cell types, including Th17 and Treg cells, thus constituting promising gene therapy targets to modulate the immune system in RA. We summarize the diagnostic and prognostic potential of blood-circulating and cell-free miRNAs, highlighting the opportunity to combine these miRNAs with antibodies to cyclic citrullinated peptide (ACCP) to allow accurate diagnosis and prognosis, particularly for seronegative patients. Furthermore, we review the evidence implicating miRNAs as promising biomarkers of efficiency and response of, and resistance to, disease-modifying anti-rheumatic drugs and immunotherapy. Finally, we discuss the autotherapeutic effect of miRNA intervention as a step toward the development of miRNA-based anti-RA drugs. Collectively, the current evidence supports miRNAs as interesting targets to better understand the pathogenetic mechanisms of RA and design more efficient therapeutic interventions.

miR-653-5p suppresses the viability and migration of fibroblast-like synoviocytes by targeting FGF2 and inactivation of the Wnt/beta-catenin pathway

Background

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease. Several studies reported that fibroblast-like synoviocytes (FLSs) and miRNAs are associated with RA pathogenesis. This study explored the function of miR-653-5p in the regulation of human fibroblast-like synoviocytes-rheumatoid arthritis (HFLS-RA) cells.

Methods

The mRNA and protein levels of genes were measured by RT-qPCR and western blot, respectively. MTT, wound healing, and invasion assays were used to evaluate the viability and metastasis of FLSs. Luciferase reporter and RNA pull-down assays were employed to determine the interaction between miR-653-5p and FGF2.

Results

RT-qPCR results demonstrated that miR-653-5p expression was decreased and FGF2 level was increased in synovial tissues and FLSs of RA. Moreover, the viability and metastasis of FLSs were accelerated by miR-653-5p addition, which was restrained by miR-653-5p suppression. Furthermore, we demonstrated that levels of Rac1, Cdc42, and RhoA were decreased after miR-653-5p addition. Besides, luciferase reporter and RNA pull-down assays implied that miR-653-5p targeted the 3′-UTR of FGF2. Functional assays showed that FGF2 overexpression neutralized the suppressive effects of miR-653-5p addition on HFLS-RA cell viability, metastasis, and the levels of Rho family proteins. Meanwhile, the levels of β-catenin, cyclin D1, and c-myc were declined by miR-653-5p supplementation, but enhanced by FGF2 addition.

Conclusion

In sum, we manifested that miR-653-5p restrained HFLS-RA cell viability and metastasis via targeting FGF2 and repressing the Wnt/beta-Catenin pathway.

ZEB1 serves an oncogenic role in the tumourigenesis of HCC by promoting cell proliferation, migration, and inhibiting apoptosis via Wnt/β-catenin signaling pathway

Zinc finger E-box-binding homeobox 1 (ZEB1), a functional protein of zinc finger family, was aberrant expressed in many kinds of liver disease including hepatic fibrosis and Hepatitis C virus. Bioinformatics results showed that ZEB1 was abnormally expressed in HCC tissues. However, to date, the potential regulatory role and molecular mechanisms of ZEB1 are still unclear in the occurrence and development of HCC. This study demonstrated that the expression level of ZEB1 was significantly elevated both in liver tissues of HCC patients and cell lines (HepG2 and SMMC-7721 cells). Moreover, ZEB1 could promote the proliferation, migration, and invasion of HCC cells. On the downstream regulation mechanism, ZEB1 could activate the Wnt/β-catenin signaling pathway by upregulating the protein expression levels of β-catenin, c-Myc, and cyclin D1. Novel studies showed that miR-708 particularly targeted ZEB1 3'-UTR regions and inhibited the HCC cell proliferation, migration, and invasion. Furthermore, results of nude mice experiments of HCC model indicated that miR-708 could inhibit tumor growth and xenograft metastasis model was established to validate that miR-708 could inhibit HCC cell metastasis through tail-vein injection in vivo. Together, the study suggested that ZEB1 modulated by miR-708 might be a potential therapeutic target for HCC therapy.

Circular RNA circ_0008360 Inhibits the Proliferation, Migration, and Inflammation and Promotes Apoptosis of Fibroblast-Like Synoviocytes by Regulating miR-135b-5p/HDAC4 Axis in Rheumatoid Arthritis

Circular RNAs (circRNAs) have been demonstrated to play crucial roles in the development and progression of many diseases, including rheumatoid arthritis (RA). However, the functions and molecular mechanism of circ_0008360 in RA remain unclear. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to determine the expression of circ_0008360, microRNA-135b-5p (miR-135b-5p), and histone deacetylase 4 (HDAC4). Cell Counting Kit-8 (CCK-8) assay, wound healing assay, and flow cytometry analysis were performed to assess cell proliferation, migration, and apoptosis, respectively. Inflammatory response was evaluated by enzyme-linked immunosorbent assay (ELISA). The interaction between miR-135b-5p and circ_0008360 or HDAC4 was predicted by bioinformatics analysis and verified by dual-luciferase reporter and RNA Immunoprecipitation (RIP) and RNA pull-down assays. Western blot assay was used to detect the protein expression of HDAC4 and proliferating cell nuclear antigen (PCNA). The expression of circ_0008360 was downregulated in RA synovial tissues and RA fibroblast-like synoviocytes (RA-FLSs). Circ_0008360 suppressed the proliferation, migration, and inflammation and promoted apoptosis of RA-FLSs, and circ_0008360 knockdown showed opposite effects. Moreover, miR-135b-5p was a direct target of circ_0008360, and miR-135b-5p could reverse the effects of circ_0008360 on proliferation, migration, inflammation, and apoptosis in RA-FLSs. Furthermore, HDAC4 was a downstream target of miR-135b-5p, and miR-135b-5p accelerated the proliferation, migration, and inflammation and suppressed apoptosis of RA-FLSs by targeting HDAC4. In addition, circ_0008360 positively regulated HDAC4 expression by sponging miR-135b-5p. Circ_0008360 inhibited the proliferation, migration, and inflammation and facilitated apoptosis of RA-FLSs by sponging miR-135b-5p and upregulating HDAC4, providing a potential target for prevention and treatment of RA.

PLD1 knockdown reduces metastasis and inflammation of fibroblast-like synoviocytes in rheumatoid arthritis by modulating NF-κB and Wnt/β-catenin pathways

Considered as an autoimmune disease, rheumatoid arthritis (RA) is an chronic inflammatory disorder that causes inflammation of the joints. This study is performed with the aim to clarify the expression of phospholipase D1 (PLD1) in RA and its specific regulation role of RA as well as the underlying mechanisms. In this study, synovial tissue samples were collected from RA patients, and RA-fibroblast-like synoviocytes (FLSs) were subsequently isolated. The expression levels of PLD1 and pathway-related proteins were detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR), western blotting or immunohistochemistry (IHC). Upon shPLD1 treatment, cell viability, proliferation, migration, invasion, and the level of inflammation-related factors were measured by Cell Counting Kit-8 (CCK-8), Edu, wound healing, Transwell and enzyme-linked immunosorbent assay (ELISA). Furthermore, C-reactive protein (CRP), rheumatoid factor (RF), arthritis score and synovial tissue lesions were assessed by collecting the blood or tissues from collagen induced arthritis (CIA) model rats. Our results showed that PLD1 level was increased in RA synovial tissues. Cell viability, proliferation, migration, invasion, and the level of inflammatory factors were reduced upon PLD1 knockdown in RA-FLSs. Moreover, p-IκBα/IκBα, β-catenin, p-IKKβ/IKKβ and TCF-4 were inhibited under PLD1 knockdown treatment. PLD1 knockdown alleviated the collagen-induced addition of arthritis score, CRP and RF, as well as the filling of inflammatory cells and proliferation of synovium in CIA model rat. To sum up, knockdown of PLD1 could reduce RA-FLSs metastasis as well as inflammatory response by modulating the activity of NF-κB and Wnt/β-catenin pathways.

Circ_0025908 regulates cell vitality and proliferation via miR-137/HIPK2 axis of rheumatic arthritis

BACKGROUND

Rheumatic arthritis (RA) is an autoimmune disease with bad effects. Recent researches have shown that circular RNAs (circRNAs) could affect the progress of RA, but the mechanism still indistinct. In this work, we explored the roles of circ_0025908 in RA.

METHODS

The levels of circ_0025908, microRNA-137 (miR-137), and mRNA of homeodomain-interacting protein kinase 2 (HIPK2) were detected by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) in RA tissues. Meanwhile, the level of HIPK2 was quantified by Western blot analysis. Besides, the cell functions were examined by CCK8 assay, EdU assay, flow cytometry assay, ELISA, and Western blot. Furthermore, the interplay between miR-137 and circ_0025908 or HIPK2 was detected by dual-luciferase reporter assay.

RESULTS

The levels of circ_0025908 and HIPK2 were upregulated, and the miR-137 level was decreased in RA tissues in contrast to that in normal tissues. For functional analysis, circ_0025908 deficiency inhibited cell vitality, cell mitotic cycle, cell proliferation, and immunoreaction in RA cells, whereas promoted cell apoptosis. Moreover, miR-137 was confirmed to repress the progression of RA cells by suppressing HIPK2. In mechanism, circ_0025908 acted as a miR-137 sponge to regulate the level of HIPK2.

CONCLUSION

Circ_0025908 facilitates the development of RA through increasing HIPK2 expression by regulating miR-137, which also offered an underlying targeted therapy for RA treatment.

The role of exosomal non-coding RNAs in aging-related diseases

Aging is a biological process caused by the accumulation of senescent cells with a permanent proliferative arrest. To the influence of aging on human life expectancy, there is essential for new biomarkers which possibly will assistance in recognizing age-associated pathologies. Exosomes, which are cell-secreted nanovesicles, make available a new biomarker detection and therapeutic approach for the transfer of different molecules with high capacity. Recently, non-coding RNAs (ncRNA) which are contained in exosomes have developed as important molecules regulating the complexity of aging and relevant human diseases. The discovery of ncRNA provided perceptions into an innovative regulatory platform that could interfere with cellular senescence. The non-coding transcriptome includes a different of RNA species, spanning from short ncRNAs (<200 nucleotides) to long ncRNAs, that are >200 bp long. Upgraded evidence displays that targeting ncRNAs possibly will influence senescence pathways. In this article, we will address ncRNAs that participated in age-related and cellular senescence diseases. Growing conception of ncRNAs in the aging process possibly will be responsible for new understandings into the improvement of age-related diseases and elongated life span.

miR-708 Negatively Regulates TNFα/IL-1β Signaling by Suppressing NF-κB and Arachidonic Acid Pathways

Two pathways commonly dysregulated in autoimmune diseases and cancer are tumor necrosis factor alpha (TNFα) and interleukin 1 beta (IL-1β) signaling. Researchers have also shown that both signaling cascades positively regulate arachidonic acid (AA) signaling. More specifically, TNFα/IL-1β promotes expression of the prostaglandin E2- (PGE2-) producing enzymes, cyclooxygenase-2 (COX-2) and microsomal prostaglandin E synthase-1 (mPGES-1). Exacerbated TNFα, IL-1β, and AA signaling have been associated with many diseases. While some TNFα therapies have significantly improved patients' lives, there is still an urgent need to develop novel therapeutics that more comprehensively treat inflammatory-related diseases. Recently, researchers have begun to use RNA interference (RNAi) to treat various diseases in the clinic. One type of RNAi is microRNA (miRNA), a class of small noncoding RNA found within cells. One miRNA in particular, miR-708, has been shown to target COX-2 and mPGES-1. Previous studies have also suggested that miR-708 may be a negative regulator of TNFα/IL-1β signaling. Therefore, we studied the relationship between miR-708, TNFα/IL-1β, and AA signaling in diseased lung cells. We found that miR-708 negatively regulates TNFα/IL-1β signaling in nondiseased lung cells, which is lost in diseased lung cells. Transient transfection of miR-708 suppressed TNFα/IL-1β-induced changes in COX-2, mPGES-1, and PGE2 levels. Moreover, miR-708 also suppressed TNFα/IL-1β-induced IL-6 independent of AA signaling. Mechanistically, we determined that miR-708 suppressed IL-6 signaling by reducing expression of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activator inhibitor of nuclear factor kappa-B kinase subunit beta (IKKβ). Collectively, our data suggest miR-708 regulates TNFα/IL-1β signaling by inhibiting multiple points of the signaling cascade.

lncRNAS56464.1 as a ceRNA promotes the proliferation of fibroblast‑like synoviocytes in experimental arthritis via the Wnt signaling pathway and sponges miR‑152‑3p

Rheumatoid arthritis (RA) is an autoimmune disease that occurs in approximately 1.0% of the general population. In RA patients, physical disability and joint damage are the major prognostic factors, which are associated with a reduction in the quality of life and early mortality. At present, the exact molecular mechanism of RA remains elusive. Long noncoding RNAs (lncRNAs) have been revealed to play a regulatory role in the pathogenesis of RA. To reveal the function of lncRNAs in rheumatoid arthritis, lncRNAS56464.1 was screened to verify its targeting of the microRNA (miR)-152-3p/Wnt pathway and its effect on the proliferation of fibroblast-like synoviocytes (FLS). In the present study, based on the competing endogenous RNA (ceRNA) theory, siRNA was designed for transfection into FLS to calculate the lncRNAS56464.1 interference efficiency and then the effect of lncRNAS56464.1 interference on FLS proliferation was detected by MTT assay. Then, lncRNAS56464.1 targeting of the miR-152-3p/Wnt pathway was detected by a dual-luciferase reporter assay. In addition, RT-qPCR, immunofluorescence and western blotting techniques were employed to detect the expression of lncRNAS56464.1, miR-152-3p and some key genes of the Wnt signaling pathway in FLS after lncRNAS56464.1 interference. The results revealed that lncRNAS56464.1 could combine with miR-152-3p and promoted the proliferation of FLS. In addition, lncRNAS56464.1 interference could not only decrease the proliferation of FLS and the expression of Wnt1, β-catenin, c-Myc, cyclin D1, and p-GSK-3β/GSK-3β, but it also increased the expression of SFRP4. The present data indicated that lncRNAS56464.1 could target the miR-152-3p/Wnt pathway to induce synovial cell proliferation and then participate in the pathogenesis of RA.

FOXM1/LINC00152 feedback loop regulates proliferation and apoptosis in rheumatoid arthritis fibroblast-like synoviocytes via Wnt/β-catenin signaling pathway

Rheumatoid arthritis (RA), a chronic systemic disease, is featured with inflammatory synovitis, which can lead to destruction on bone and cartilage and even cause disability. Emerging studies demonstrated that Fibroblast-like synoviocytes (FLS) is a vital cellular participant in RA progression. Long non-coding RNAs (lncRNAs) are also reported to participate in the pathogenesis of RA. In our present study, lncRNA microarray analysis was applied to screen out lncRNAs differentially expressed in RA FLS. Among which, cytoskeleton regulator RNA (LINC00152) presented biggest fold change. Gain- or loss-of function assays were further carried out in RA FLS, and the results revealed that LINC00152 promoted proliferation but induced apoptosis in RA FLS. Furthermore, up-regulation of LINC00152 may induce promotion of Wnt/β-catenin signaling pathway in RA FLS. Mechanistically, we found that forkhead box M1 (FOXM1) transcriptionally activated LINC00152 in RA FLS. Additionally, LINC00152 positively regulated FOXM1 via sponging miR-1270. In conclusion, the present study focused on elucidating the function of FOXM1/LINC00152 positive feedback loop in RA FLS and its association with Wnt/β-catenin signaling.

miR-431-5p regulates cell proliferation and apoptosis in fibroblast-like synoviocytes in rheumatoid arthritis by targeting XIAP

BACKGROUND

miR-431-5p is dysregulated in various cancers and plays an important function in the development of cancer. However, its role in fibroblast-like synoviocytes (FLSs) in patients with rheumatoid arthritis (RA) remains to be understood.

METHODS

Quantitative real-time polymerase chain reaction was used to detect the relative expression of miR-431-5p in synovial tissues and FLSs. Cell proliferation assays helped examine RA FLS proliferation. Flow cytometry was performed to determine apoptosis and cell cycle progression in RA FLSs. We used dual-luciferase assays to determine the correlation between miR-431-5p and its putative target, X-linked inhibitor of apoptosis (XIAP). Quantitative real-time PCR and western blotting were used to measure XIAP levels in synovial tissues and transfected RA FLSs.

RESULTS

miR-431-5p was downregulated in synovial tissues and FLSs of patients with RA. Upregulation of miR-431-5p prohibited cell proliferation and the G0/G1-to-S phase transition but promoted apoptosis in RA FLSs, while miR-431-5p inhibition showed the opposite results. miR-431-5p directly targeted XIAP in RA FLSs and reversely correlated with XIAP levels in synovial tissues. Notably, XIAP silencing partially restored the effects of miR-431-5p inhibition in RA FLSs.

CONCLUSION

miR-431-5p regulates cell proliferation, apoptosis, and cell cycle of RA FLSs by targeting XIAP, suggesting its potential in the treatment of RA.

miR-708 affords protective efficacy in anoxia/reoxygenation-stimulated cardiomyocytes by blocking the TLR4 signaling via targeting HMGB1

Ischemic heart disease is a proverbial and common cardiovascular disease, and constitutes a leading cause of disability and mortality globally. Myocardial ischemic/reperfusion (MI/R) injury is a highly orchestrated phenomenon that involves the excessive activation of high mobility group box 1 (HMGB1) signaling. In the present study, we sought to investigate the function of miR-708 in MI/R injury due to the predicted binding to HMGB1. Intriguingly, down-regulation of miR-708 and up-regulation of HMGB1 were observed in MI/R rat model and H9c2 cardiomyocytes exposed to hypoxia/reoxygenation (H/R) conditions. Dual luciferase reporter assays substantiated that HMGB1 was a direct target of miR-708. Moreover, miR-708 overexpression suppressed the mRNA and protein expression of HMGB1. Noticeably, elevation of miR-708 antagonized H/R-induced inhibition in cell viability; whilst, increased cell apoptosis evoked by H/R was restrained after miR-708 up-regulation. Simultaneously, miR-708 elevation suppressed H/R exposure-increased lactate dehydrogenase (LDH) release and reactive oxygen species (ROS) generation, but elevated the activity of anti-oxidative stress superoxide dismutase (SOD). Additionally, H/R-increased production of pro-inflammatory cytokine TNF-α and IL-6 was offset following miR-708 overexpression. Moreover, enhancement of miR-708 inhibited H/R-evoked activation of the HMGB1-TLR4-NF-κB pathway by inhibiting the protein levels of HMGB1, TLR4 and p-p65 NF-κB. Specially, restoring this pathway offset the protective effects of miR-708 on H/R-induced cardiomyocyte injury. Together, these data indicate that miR-708 may protect against H/R-induced cardiomyocyte damage by directing targeting HMGB1 signaling, implying a promising therapeutic agent against ischemic heart disease including myocardial infarction.

TNF-α-elicited miR-29b potentiates resistance to apoptosis in peripheral blood monocytes from patients with rheumatoid arthritis

CD14-positive monocytes from patients with rheumatoid arthritis (RA) are more resistant to apoptosis, which promotes their persistence at the inflammatory site and thereby contributes crucially to immunopathology. We sought to elucidate one mechanism underlying this unique pathogenesis: resistance to apoptosis and the potential involvement of miR-29b in this process. CD14-positive peripheral blood monocytes (PBMs) from RA patients were observed to be resistant to spontaneous apoptosis compared to PBMs from healthy volunteers. Intriguingly, expression of miR-29b was significantly upregulated in PBMs from RA patients than those from healthy volunteers, and this upregulation was correlated with RA disease activity. Functionally, forced expression of the exogenous miR-29b in CD14-positive Ctrl PBMs conferred resistance to spontaneous apoptosis and Fas-induced death, thereafter enhancing the production of major proinflammatory cytokines in there cells. Following identification of the potential miR-29b target transcripts using bioinformatic algorithms, we showed that miR-29b could directly bind to the 3'-UTR of the high-mobility group box-containing protein 1 (HBP1) and inhibited its transcription in PBMs. Importantly, stable expression of the exogenous HBP1 in differentiated THP-1 monocytes effectively abolished miR-29b-elicited resistance to Fas-induced apoptosis. Finally, among patients with RA and good clinical responses to immunotherapy, expression levels of miR-29b were significantly compromised in those treated with infliximab (a TNF-α inhibitor) but not in those treated with tocilizumab (a humanized mAb against the IL-6 receptor), pointing to a potential association between miR-29b activation and TNF-α induction. The available data collectively suggest that TNF-α-elicited miR-29b potentiates resistance to apoptosis in PBMs from RA patients via inhibition of HBP1 signaling, and testing patients for miR-29b/HBP1 expression ratios may provide more accurate prognostic information and could influence the recommended course of immunotherapy.

Long non-coding RNA MINCR aggravates colon cancer via regulating miR-708-5p-mediated Wnt/β-catenin pathway

BACKGROUND

Increasing evidence has found that the dysregulation of long non-coding RNAs (lncRNAs) may be important indicators in tumorigenesis. MYC-induced long non-coding RNA (MINCR) has been found to be related with some cancers, such as non-small cell lung cancer and gallbladder cancer. Besides, MINCR has potentially prognostic value for colon cancer (CC) patients' prognosis, yet its function and molecular mechanism in CC are not explored.

METHODS

qRT-PCR evaluated gene expression, and western blot detected protein level. In vitro and in vivo experiments were adopted to understand the biological role of MINCR in CC. TOP/FOP Flash assay was performed to measure the activity of Wnt/β-catenin pathway. RNA pull down, luciferase reporter and RIP assays were utilized to analyze the relationship among genes. Immunohistochemistry and HE staining techniques were utilized to evaluate Ki67 staining in xenografts.

RESULTS

MINCR was up-regulated in CC cells. Knockdown of MINCR suppressed cell proliferation and migration. MINCR could up-regulate CTNNB1 via sequestering miR-708-5p, resulting in activated Wnt/β-catenin pathway. The addition of LiCl treatment, miR-708-5p inhibitor or pcDNA3.1/CTNNB1 abolished the inhibitory impacts induced by MINCR silence in CC progression.

CONCLUSION

MINCR sponges miR-708-5p to up-regulate CTNNB1 and activate Wnt/β-catenin pathway, thus promoting the development CC. Targeting MINCR might shed new light on the therapeutic strategies of CC.

Searching for valuable differentially expressed miRNAs in postmenopausal osteoporosis by RNA sequencing

AIM

Postmenopausal osteoporosis is a systemic and chronic bone disease in women. In order to understand the pathological mechanism of postmenopausal osteoporosis, we aimed to find the potential differentially expressed miRNAs in the disease.

METHODS

Firstly, RNA sequencing was used to identify differentially expressed miRNAs, followed by the construction of the miRNA-target mRNA regulatory network. Then, Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes were used to analyze the biological function of target mRNAs. Finally, electronic validation of identified differentially expressed miRNAs and target mRNAs was performed.

RESULTS

A total of 33 differentially expressed miRNAs (18 upregulated and 15 downregulated miRNAs) and 6820 miRNA-mRNA pairs were identified. Among which, seven miRNAs with high degree including hsa-miR-17-5p, hsa-miR-1-3p, hsa-miR-193b-3p, hsa-miR-125b-5p, hsa-miR-10b-5p, hsa-miR-100-5p and hsa-miR-30a-3p were obtained in the miRNA-mRNA regulatory network. TGF-beta was the most significantly enriched signaling pathway of target mRNAs. The electronic validation result of hsa-miR-1-3p, hsa-miR-193b-3p, hsa-miR-10b-5p, hsa-miR-100-5p, hsa-miR-133b, hsa-miR-708-5p, CRK, RAB5C, CCND1 and PCYOX1 was consisted with the RNA sequencing analysis.

CONCLUSION

Dysfunctional miRNAs may play significant roles in postmenopausal osteoporosis.

Role of microRNAs in the Development of Cardiovascular Disease in Systemic Autoimmune Disorders

Rheumatoid Arthritis (RA), Systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS) are the systemic autoimmune diseases (SADs) most associated with an increased risk of developing cardiovascular (CV) events. Cardiovascular disease (CVD) in SADs results from a complex interaction between traditional CV-risk factors, immune deregulation and disease activity. Oxidative stress, dyslipidemia, endothelial dysfunction, inflammatory/prothrombotic mediators (cytokines/chemokines, adipokines, proteases, adhesion-receptors, NETosis-derived-products, and intracellular-signaling molecules) have been implicated in these vascular pathologies. Genetic and genomic analyses further allowed the identification of signatures explaining the pro-atherothrombotic profiles in RA, SLE and APS. However, gene modulation has left significant gaps in our understanding of CV co-morbidities in SADs. MicroRNAs (miRNAs) are emerging as key post-transcriptional regulators of a suite of signaling pathways and pathophysiological effects. Abnormalities in high number of miRNA and their associated functions have been described in several SADs, suggesting their involvement in the development of atherosclerosis and thrombosis in the setting of RA, SLE and APS. This review focusses on recent insights into the potential role of miRNAs both, as clinical biomarkers of atherosclerosis and thrombosis in SADs, and as therapeutic targets in the regulation of the most influential processes that govern those disorders, highlighting the potential diagnostic and therapeutic properties of miRNAs in the management of CVD.

MiR-145-5p mitigates dysregulated Wnt1/β-catenin signaling pathway in rheumatoid arthritis

Fibroblast-like synoviocytes (FLS) lining the arthritic synovial joint region have been implicated to be a key player in bone remodeling. The uncontrolled proliferation of this cell subtype is strictly regulated by various molecular elements including microRNAs (miRNAs). The Wnt1/β-catenin signaling pathway plays a crucial role in the survival of FLS cells. This study explores the underlying mechanism of miR-145-5p towards the Wnt1/β-catenin pathway. MiR-145-5p depicted a strong binding affinity towards frizzled class receptor 4 (FZD4) 3' UTR, a key receptor complex essential for recognizing circulating Wnt1 molecules. Adjuvant induced arthritic fibroblast-like synoviocytes (AA-FLS) isolated from rats stimulated with Wnt1 (10 ng/ml) elicited active Wnt1/β-catenin signaling. Transfection of miR-145-5p mimic (50 pmol) to AA-FLS stimulated with Wnt1 elicited reduced expression levels of various factors of Wnt1/β-catenin signaling including low-density lipoprotein receptor-related protein 5 (LRP5), dishevelled segment polarity protein 1 (Dvl1) and β-catenin transcription factor. Moreover, pro-inflammatory cytokines (TNFα, IL-1β, IL-6 and IL-23) were regulated compared to the diseased groups. Furthermore, miR-145-5p counterbalanced the levels of receptor activator of nuclear factor kappa B ligand (RANKL) and osteoprotegerin (OPG) at the cellular level, essential for bone remodeling. Hence, we suggest that miR-145-5p regulates the survival/proliferation of FLS cells in RA disease condition through attenuation of Wnt1/β-catenin signaling.

Berberine encapsulated PEG-coated liposomes attenuate Wnt1/β-catenin signaling in rheumatoid arthritis via miR-23a activation

Bone erosion is a debilitating pathological process of osteopathic disorder like rheumatoid arthritis (RA). Current treatment strategies render low disease activity but with disease recurrence. To find an alternative, we designed this study with an aim to explore the underlying therapeutic effect of PEGylated liposomal BBR (PEG-BBR) against Wnt1/β-catenin mediated bone erosion in adjuvant-induced arthritic (AA) rat model and fibroblast-like synoviocytes (FLS) with reference to microRNA-23a (miR-23a) activity. Our initial studies using confocal microscopy and Near-Infrared Imaging (NIR) showed successful internalization of PEG-BBR and PEG-miR-23a in vitro and in vivo respectively and was retained till 48 h. The preferential internalization of PEG-BBR into the inflamed joint region significantly reduced the gene and protein level expression of major Wnt1 signaling mediators and reduced bone erosion in rats. Moreover, PEG-BBR treatment in FLS cells attenuated the gene and protein expression levels of FZD4, LRP5, β-catenin, and Dvl-1 through the induction of CYLD. Furthermore, inhibition of these factors resulted in reduced bone loss and increased calcium retainability by altering the RANKL/OPG axis. PEG-BBR treatment markedly inhibited the expression of LRP5 protein on par with the DKK-1 (LRP5/Wnt signaling inhibitor) and suppressed the transcriptional activation of β-catenin inside the cells. We further witnessed that miR-23a altered the expression levels of LRP5 through RNA interference. Overall, our findings endorsed that miR-23a possesses a multifaceted therapeutic efficiency like berberine in RA pathogenesis and can be considered as a potential candidate for therapeutic targeting of Wnt1/β-catenin signaling in RA disease condition.

Non-coding RNAs in Rheumatoid Arthritis: From Bench to Bedside

Rheumatoid arthritis is a common systemic and autoimmune disease characterized by symmetrical and inflammatory destruction of distal joints. Its primary pathological characters are synovitis and vasculitis. Accumulating studies have implicated the critical role of non-coding RNAs (ncRNAs) in inflammation and autoimmune regulation, primarily including microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA). NcRNAs are significant regulators in distinct physiological and pathophysiological processes. Many validated non-coding RNAs have been identified as promising biomarkers for the diagnosis and treatment of RA. This review will shed some light on RA pathogenesis and be helpful for identifying potential ncRNA biomarkers for RA.

Effects of miR-150-5p on the growth and SOCS1 expression of rheumatoid arthritis synovial fibroblasts

OBJECTIVE

miR-150-5p has been implicated in the regulation and onset of immune diseases. We investigated the effects of miR-150-5p on the functions of RA synovial fibroblasts (RASFs).

METHOD

The binding site between suppressor of cytokine signaling 1 (SOCS1) and miR-150-5p was analyzed using European Bioinformatics Institute database, and the 3' UTR of SOCS1 mRNA, including the binding site, was amplified and ligated to the 3'-end of LUC2 gene in the pmirGL0 dual-luciferase vector. The pmirGL0 vector and corresponding mimics were subsequently co-transfected into 293T cells to compare the relative fluorescence intensity of LUC2 between the miR-150-5p mimics and the negative control (NC) mimics groups. Further, the RASF cell line MH7A was transfected with miR-150-5p or NC mimics and subjected to flow cytometric analysis, cell counting kit-8 assay, western blot analysis, qPCR, and enzyme-linked immunosorbent (ELISA) assay 48 h after transfection.

RESULTS

miR-150-5p mimics resulted in a lower cell apoptotic rate and proportion of cells in the S phase. Using a dual-luciferase reporter gene assay, we then found that SOCS1 is a potential target of miR-150-5p. Compared with NC mimics, miR-150-5p mimics significantly decreased the protein and mRNA expression levels of SOCS1. ELISA assay showed that miR-150-5p mimics increased interleukin-6 level in the cell culture medium but did not influence tumor necrosis factor-alpha levels.

CONCLUSIONS

Overall, the growth-promoting effect of miR-150-5p on MH7A cells may be attributed to the miR-150-5p-induced degradation of SOCS1 mRNA, suggesting a potential therapeutic target for RA.Key Points• SOCS1 is a potential target of miR-150-5p.• miR-150-5p promoted the growth of RASF cell line MH7A.• miR-150-5p increased the secretion of IL-6 but did not significantly affect TNF-α levels in MH7A cells.

miRNAs as Therapeutic Targets in Inflammatory Disease

In the past decade, we have witnessed considerable developments in understanding the roles and functions of miRNAs. In parallel, the identification of alterations in miRNA expression in inflammatory disease indicates their potential as therapeutic targets. Pharmacological treatments targeting abnormally expressed miRNAs for inflammatory diseases are not yet in clinical practice; however, some small compounds and nucleic acids targeting miRNAs have shown promise in preclinical development. Here, we focus on recent advances in understanding miRNA deregulation in inflammatory diseases and provide an overview of the current development of miRNA-based therapeutics in these diseases with an emphasis on newly discovered miRNA therapeutic targets.

MicroRNAs in rheumatoid arthritis: From pathogenesis to clinical impact

Over the last decade, many epigenetic mechanisms that contribute in the pathogenesis of autoimmune disorders have been revealed. MicroRNAs (miRNAs) are small, non-coding, RNA molecules that bind to messenger RNAs and disrupt the transcription of target genes. Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease in which a plethora of epigenetic changes take place. Current research on RA epigenetics has focused mainly on miRNAs. Genetic variance of some miRNA genes, especially miR-499, might predispose an individual to RA development. Additionally, altered expression of many miRNAs has been discovered in several cells, tissues and body fluids in patients with RA. MiRNAs expression also differs depending on disease's stage and activity. Serum miR-22 and miR-103a might predict RA development in susceptible individuals (pre-RA), while serum miR-16, miR-24, miR-125a and miR-223 levels are altered in early RA (disease duration <12 months) patients compared to established RA or healthy individuals. Moreover, serum miR-223 levels have been associated with RA activity and disease relapse. What is more, serum levels of several miRNAs, including miR-125b and miR-223, could be used to predict response to RA treatment. Finally, miRNA analogs or antagonists have been used as therapeutic regimens in experimental arthritis models and have demonstrated promising results. In conclusion, the research on the miRNA alterations in RA sheds light to several aspects of RA pathogenesis, introduces new biomarkers for RA diagnosis and treatment response prediction and offers the opportunity to discover new, targeted drugs for patients with RA.

Differential Expression Profiles of the Transcriptome and miRNA Interactome in Synovial Fibroblasts of Rheumatoid Arthritis Revealed by Next Generation Sequencing

Using next-generation sequencing to decipher the molecular mechanisms underlying aberrant rheumatoid arthritis synovial fibroblasts (RASF) activation, we performed transcriptome-wide RNA-seq and small RNA-seq on synovial fibroblasts from rheumatoid arthritis (RA) subject and normal donor. Differential expression of mRNA and miRNA was integrated with interaction analysis, functional annotation, regulatory network mapping and experimentally verified miRNA–target interaction data, further validated with microarray expression profiles. In this study, 3049 upregulated mRNA and 3552 downregulated mRNA, together with 50 upregulated miRNA and 35 downregulated miRNA in RASF were identified. Interaction analysis highlighted contribution of miRNA to altered transcriptome. Functional annotation revealed metabolic deregulation and oncogenic signatures of RASF. Regulatory network mapping identified downregulated FOXO1 as master transcription factor resulting in altered transcriptome of RASF. Differential expression in three miRNA and corresponding targets (hsa-miR-31-5p:WASF3, hsa-miR-132-3p:RB1, hsa-miR-29c-3p:COL1A1) were also validated. The interactions of these three miRNA–target genes were experimentally validated with past literature. Our transcriptomic and miRNA interactomic investigation identified gene signatures associated with RASF and revealed the involvement of transcription factors and miRNA in an altered transcriptome. These findings help facilitate our understanding of RA with the hope of serving as a springboard for further discoveries relating to the disease.

Relevance function of microRNA-708 in the pathogenesis of cancer

MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression post-transcriptionally responsible for regulating >70% of human genes. MicroRNA-708 (miR-708) is encoded in the intron 1 of the Odd Oz/ten-m homolog 4 (ODZ4) gene. Numerous researches have confirmed that the abnormal expressed miR-708 is involved in the regulation of multiple types of cancer. Notably, the expression level of miR-708 was higher in lung cancer, bladder cancer (BC) and colorectal cancer (CRC) cell lines while lower in hepatocellular carcinoma (HCC), prostate cancer (PC), gastric cancer (GC) and so on. This review provides a current view on the association between miR-708 and several cancers and focuses on the recent studies of miR-708 regulation, discussing its potential as an epigenetic biomarker and therapeutic target for these cancers. In particular, the regulated mechanisms and clinical application of miR-708 in these cancers are also discussed.