The role of microRNA in rheumatoid arthritis and other autoimmune diseases

miR-126: a bridge between cancer and exercise

The microRNA miR-126 supports endothelial cells and blood vessel integrity. Recent research has shown that it also serves as a key link between exercise and cancer. This article delves into how exercise affects the expression of miR-126, impacting cardiovascular well-being and metabolic control. The article also examines the various contributions of miR-126 in cancer, acting as both a suppressor and an enhancer depending on the particular context. Regular aerobic exercises, including HIIT, consistently increase levels of miR-126, leading to enhanced angiogenesis, endothelial repair, and improved vascular function through mechanisms involving VEGF, HIF-1α, and EPC mobilization. Resistance training affects similar pathways, but does not cause a significant change in miR-126 levels.MiR-126 involves in cancer by suppressing tumor growth and controlling key pathways such as PI3K/Akt, ERK/MAPK, and EMT. Lower levels are associated with negative outcomes, later stages of the disease, and increased spread of different types of cancer like glioblastoma, CRC, ovarian, esophageal, gastric, and prostate cancer.The relationship between exercise and cancer suggests a possible therapeutic approach, where the regulation of miR-126 through exercise could help improve vascular function and slow tumor growth. Further studies should focus on understanding the specific molecular pathways through which miR-126 connects these areas, leading to potential interventions that utilize its regulatory network to promote cardiovascular well-being and enhance cancer treatment.

The Identification of Novel Therapeutic Biomarkers in Rheumatoid Arthritis: A Combined Bioinformatics and Integrated Multi-Omics Approach

Rheumatoid arthritis (RA) is a multifaceted autoimmune disease that is marked by a complex molecular profile influenced by an array of factors, including genetic, epigenetic, and environmental elements. Despite significant advancements in research, the precise etiology of RA remains elusive, presenting challenges in developing innovative therapeutic markers. This study takes an integrated multi-omics approach to uncover novel therapeutic markers for RA. By analyzing both transcriptomics and epigenomics datasets, we identified common gene candidates that span these two omics levels in patients diagnosed with RA. Remarkably, we discovered eighteen multi-evidence genes (MEGs) that are prevalent across transcriptomics and epigenomics, twelve of which have not been previously linked directly to RA. The bioinformatics analyses of the twelve novel MEGs revealed they are part of tightly interconnected protein-protein interaction networks directly related to RA-associated KEGG pathways and gene ontology terms. Furthermore, these novel MEGs exhibited direct interactions with miRNAs linked to RA, underscoring their critical role in the disease's pathogenicity. Overall, this comprehensive bioinformatics approach opens avenues for identifying new candidate markers for RA, empowering researchers to validate these markers efficiently through experimental studies. By advancing our understanding of RA, we can pave the way for more effective therapies and improved patient outcomes.

MicroRNAs in idiopathic inflammatory myopathies: state-of-the-art and future perspectives

PURPOSE OF REVIEW

Idiopathic inflammatory myopathies (IIMs) are a group of rare autoimmune disorders characterized by muscle weakness and inflammation. MicroRNAs (miRNAs) are the main class of small noncoding RNAs regulating a wide range of physiological and pathological processes and play a role in mediating autoimmunity and inflammation. In this review, we summarize the latest knowledge on the role of miRNAs in systemic autoimmune diseases with particular focus on IIMs.

RECENT FINDINGS

Study on miRNA expression in IIMs is helping in understanding the pathogenetic basis of the disease at a tissue and systemic level. Several miRNAs, even with a muscle-specific expression (myomiRs), have been shown to be involved in immune and nonimmune mechanisms of myofiber damage. MiRNAs modulate and orchestrate the local inflammatory infiltrate and could be used as potential biomarkers as they correlate with disease activity and response to therapy.

SUMMARY

IIMs comprise different clinical phenotypes and still little is known about the molecular signature of each subset. Further research about miRNA profiling will provide additional insights in the disease characterization with an expected impact on the therapeutic strategies.

Impact of miR-155 rs767649 Polymorphism on Rheumatoid Arthritis Activity in Egyptian Patients

BACKGROUND

Rheumatoid arthritis (RA) is a chronic inflammatory condition that impacts not only the musculoskeletal system but also various other systems in the body, including the cutaneous, ocular, respiratory, cardiovascular, and circulatory systems. MicroRNAs (miRNAs) are a class of naturally occurring and highly conserved transcripts that primarily function in the regulation of gene expression. They accomplish this by facilitating the degradation of messenger RNA (mRNA) or by repressing mRNA translation. miRNAs are well-known regulators of a variety of cellular processes. Therefore, we aimed to detect the impact of miR-155 rs767649 polymorphism on RA activity.

METHODS

This case-control study included 66 Egyptian patients with RA who visited Al-Zhraa University Hospital, Internal Medicine Department, Cairo, Egypt, and 50 apparently healthy control subjects matched for age and sex. The participants were subjected to full clinical evaluation, including assessments of the disease activity score (DAS), erythrocyte sedimentation rate (ESR), liver and kidney function, anti-cyclic citrullinated peptide antibody (anti-CCP), and miR-155 polymorphism using real-time polymerase chain reaction (PCR).

RESULTS

In the RA group, the majority (98.5%) were female, with a mean age of 43 years, while in the control group, 94% were female, with a mean age of 43.4 years. Comparison of laboratory parameters indicated significantly lower hemoglobin levels, higher ESR, and higher serum creatinine and anti-CCP levels in the RA group than in the control group. The RA group had a significantly higher frequency of TT genotypes and significantly lower frequencies of TA and TT genotypes than the control group. Considering the TT genotype and T allele as references, TA, AA, and TA/AA genotypes in the dominant model; AA in the recessive model; and A allele were significantly associated with protective effects against RA development (p<0.05, odds ratio<1).

CONCLUSION

rs767649, the functional variant of miR-155, plays an important role in susceptibility to the increased risk of RA, suggesting that miR-155 can be used as a therapeutic target for the treatment of Egyptian patients with RA.

Genetically Engineered Exosomes as a Potential Regulator of Th1 Cells Response in Rheumatoid Arthritis

Background: Rheumatoid arthritis is a long-lasting inflammatory disease that usually involves joints, but it can also affect other organs, including the skin and lungs. In this case, it is important to maintain a balance between beneficial pro-inflammatory activity and harmful overactivation of the T helper cells (Th). We strive to investigate in this study the possibilities for the effect of mesenchymal stem cells (MSCs)-derived exosomes containing miR-146a/miR-155 on the lymphocyte population and function. Methods: Exosomes were isolated from overexpressed miR-146a/miR-155 MSCs for the purpose of this analysis. Splenocytes were isolated from collagen-induced arthritis (CIA) and control mice. It was important to consider the expressions of certain predominant autoimmune-response genes, including T-bet and interferon-γ (IFNγ), by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay. It turned out to be a significant consideration with p < 0.05. Results: The results are expressed in percentages with respect to miR-146a/AntimiR-155 transduced MSC-derived exosomes treatment, which significantly decreased the mRNA expression level of IFNγ in healthy mice (p < 0.05). miR-146a transduced MSC-derived exosomes treatment significantly reduced the mRNA expression level of IFNγ in CIA mice (p < 0.05). It should be noted that the secretion of the pro-inflammatory factor IFNγ in CIA mice was inhibited in almost all groups (p < 0.05). Conclusion: Many research groups have mainly focused on strategies for reducing pro-inflammatory cytokines. This approach was recently suggested and investigated in our research team and suggested that manipulation of MSCs-derived exosomes could minimize pro-inflammatory cytokine production to strike a balance among Th subsets. These approaches tend to appear to achieve better results in the regulation of the immune system by the use of engineered exosomes derived from MSCs. By providing accurate information the reasonably practicable use of exosomes for cell-free therapy can be established.

Matrix metalloproteinases in rheumatoid arthritis and osteoarthritis: a state of the art review

Although the pathological mechanisms involved in osteoarthritis (OA) and rheumatoid arthritis (RA) are different, the onset and progression of both diseases are associated with several analogous clinical manifestations, inflammation, and immune mechanisms. In both diseases, cartilage destruction is mediated by matrix metalloproteinases (MMPs) synthesized by chondrocytes and synovium fibroblasts. This review aims to summarize recent articles regarding the role of MMPs in OA and RA, as well as the possible methods of targeting MMPs to alleviate the degradation processes taking part in OA and RA. The novel experimental MMP-targeted treatments in OA and RA are MMP inhibitors eg. 3-B2, taraxasterol, and naringin, while other treatments aim to silence miRNAs, lncRNAs, or transcription factors. Additionally, other recent MMP-related developments include gene polymorphism of MMPs, which have been linked to OA susceptibility, and the MMP-generated neoepitope of CRP, which could serve as a biomarker of OA progression.

Fluorinated polyamidoamine dendrimer-mediated miR-23b delivery for the treatment of experimental rheumatoid arthritis in rats

In rheumatoid arthritis (RA), insufficient apoptosis of macrophages and excessive generation of pro-inflammatory cytokines are intimately connected, accelerating the development of disease. Here, a fluorinated polyamidoamine dendrimer (FP) is used to deliver miR-23b to reduce inflammation by triggering the apoptosis of as well as inhibiting the inflammatory response in macrophages. Following the intravenous injection of FP/miR-23b nanoparticles in experimental RA models, the nanoparticles show therapeutic efficacy with inhibition of inflammatory response, reduced bone and cartilage erosion, suppression of synoviocyte infiltration and the recovery of mobility. Moreover, the nanoparticles accumulate in the inflamed joint and are non-specifically captured by synoviocytes, leading to the restoration of miR-23b expression in the synovium. The miR-23b nanoparticles target Tab2, Tab3 and Ikka to regulate the activation of NF-κB pathway in the hyperplastic synovium, thereby promoting anti-inflammatory and anti-proliferative responses. Additionally, the intravenous administration of FP/miR-23b nanoparticles do not induce obvious systemic toxicity. Overall, our work demonstrates that the combination of apoptosis induction and inflammatory inhibition could be a promising approach in the treatment of RA and possibly other autoimmune diseases.

The role of microRNAs in regulating inflammation and exercise-induced adaptations in rheumatoid arthritis

MicroRNAs (miRNAs) are endogenously generated single-stranded RNAs that play crucial roles in numerous biological processes, such as cell development, proliferation, differentiation, metabolism and apoptosis. They negatively regulate target gene expression by repressing translation of messenger RNA into a functional protein. Several miRNAs have been implicated in the development and progression of RA. They are involved in inflammatory and immune processes and are associated with susceptibility to RA and disease activity. They are also considered to be potential markers of disease activity or even therapeutic targets. Likewise, several miRNAs are affected acutely by exercise and regulate exercise-related adaptations in the skeletal muscle and cardiovascular system and aerobic fitness. Interestingly, some miRNAs affected by exercise are also important in the context of RA. Investigating these might increase our understanding of the effects of exercise in RA and improve exercise prescription and, potentially, disease management. In this review, we focus on the miRNAs that are associated with both RA and exercise and discuss their roles in (and potential interactions between) RA and exercise-induced adaptations.

The Beneficial Effects of Pine Nuts and Its Major Fatty Acid, Pinolenic Acid, on Inflammation and Metabolic Perturbations in Inflammatory Disorders

Inflammatory disorders such as atherosclerosis, diabetes and rheumatoid arthritis are regulated by cytokines and other inflammatory mediators. Current treatments for these conditions are associated with significant side effects and do not completely suppress inflammation. The benefits of diet, especially the role of specific components, are poorly understood. Polyunsaturated fatty acids (PUFAs) have several beneficial health effects. The majority of studies on PUFAs have been on omega-3 fatty acids. This review will focus on a less studied fatty acid, pinolenic acid (PNLA) from pine nuts, which typically constitutes up to 20% of its total fatty acids. PNLA is emerging as a dietary PUFA and a promising supplement in the prevention of inflammatory disorders or as an alternative therapy. Some studies have shown the health implications of pine nuts oil (PNO) and PNLA in weight reduction, lipid-lowering and anti-diabetic actions as well as in suppression of cell invasiveness and motility in cancer. However, few reviews have specifically focused on the biological and anti-inflammatory effects of PNLA. Furthermore, in recent bioinformatic studies on human samples, the expression of many mRNAs and microRNAs was regulated by PNLA indicating potential transcriptional and post-transcriptional regulation of inflammatory and metabolic processes. The aim of this review is to summarize, highlight, and evaluate research findings on PNO and PNLA in relation to potential anti-inflammatory benefits and beneficial metabolic changes. In this context, the focus of the review is on the potential actions of PNLA on inflammation along with modulation of lipid metabolism and oxidative stress based on data from both in vitro and in vivo experiments, and human findings, including gene expression analysis.

Downexpression of miR-200c-3p Contributes to Achalasia Disease by Targeting the PRKG1 Gene

Achalasia is an esophageal smooth muscle motility disorder with unknown pathogenesis. Taking into account our previous results on the downexpression of miR-200c-3p in tissues of patients with achalasia correlated with an increased expression of PRKG1, SULF1, and SYDE1 genes, our aim was to explore the unknown biological interaction between these genes and human miR-200c-3p and if this relation could unravel their functional role in the etiology of achalasia. To search for putative miR-200c-3p binding sites in the 3'-UTR of PRKG1, SULF1 and SYDE1, a bioinformatics tool was used. To test whether PRKG1, SULF1, and SYDE1 are targeted by miR-200c-3p, a dual-luciferase reporter assay and quantitative PCR on HEK293 and fibroblast cell lines were performed. To explore the biological correlation between PRKG1 and miR-200c-3p, an immunoblot analysis was carried out. The overexpression of miR-200c-3p reduced the luciferase activity in cells transfected with a luciferase reporter containing a fragment of the 3'-UTR regions of PRKG1, SULF1, and SYDE1 which included the miR-200c-3p seed sequence. The deletion of the miR-200c-3p seed sequence from the 3'-UTR fragments abrogated this reduction. A negative correlation between miR-200c-3p and PRKG1, SULF1, and SYDE1 expression levels was observed. Finally, a reduction of the endogenous level of PRKG1 in cells overexpressing miR-200c-3p was detected. Our study provides, for the first time, functional evidence about the PRKG1 gene as a direct target and SULF1 and SYDE1 as potential indirect substrates of miR-200c-3p and suggests the involvement of NO/cGMP/PKG signaling in the pathogenesis of achalasia.

Analysis of the miRNA expression from the adipose tissue surrounding the adrenal neoplasia

Background

Primary aldosteronism (PA) is characterized by several metabolic changes such as insulin resistance, metabolic syndrome, and adipose tissue (AT) inflammation. Mi(cro)RNAs (miRNAs) are a class of non-coding small RNA molecules known to be critical regulators in several cellular processes associated with AT dysfunction. The aim of this study was to evaluate the expression of some miRNAs in visceral and subcutaneous AT in patients undergoing adrenalectomy for aldosterone-secreting adrenal adenoma (APA) compared to the samples of AT obtained in patients undergoing adrenalectomy for non-functioning adrenal mass (NFA).

Methods

The quantitative expression of selected miRNA using real-time PCR was analyzed in surrounding adrenal neoplasia, peri-renal, and subcutaneous AT samples of 16 patients with adrenalectomy (11 patients with APA and 5 patients with NFA).

Results

Real-time PCR cycles for miRNA-132, miRNA-143, and miRNA-221 in fat surrounding adrenal neoplasia and in peri-adrenal AT were significantly higher in APA than in patients with NFA. Unlike patients with NFA, miRNA-132, miRNA-143, miRNA-221, and miRNA-26b were less expressed in surrounding adrenal neoplasia AT compared to subcutaneous AT in patients with APA.

Conclusion

This study, conducted on tissue expression of miRNAs, highlights the possible pathophysiological role of some miRNAs in determining the metabolic alterations in patients with PA.

MicroRNA-122-3p plays as the target of long non-coding RNA LINC00665 in repressing the progress of arthritis

MicroRNAs (miRNAs) play important roles in many diseases, including rheumatoid arthritis (RA). However, the mechanisms underlying the effects of miR-122-3p-3p on RA are not distinct and require further investigation. Patients with RA and healthy controls were recruited to analyze the miR-122-3p levels. The MH7A cells were stimulated with interleukin (IL)-1β to mimic the local inflammation of RA. Cell Counting Kit-8 (CCK-8) and flow cytometry were performed to measure the viability and apoptosis of MH7A cells. Diana tools and TargetScan were used to predict the target relationships. Luciferase reporter assay was used to validate the target relationship. miR-122-3p is downregulated in RA patients and IL-1β-stimulated MH7A cells. miR-122-3p suppresses MH7A cell viability and promotes MH7A cell apoptosis. miR-122-3p targets LINC00665. LINC00665 eliminates the inhibitory effect of miR-122-3p on IL-1β-stimulated MH7A cells. Eukaryotic translation initiation factor 2 alpha kinase 1 (EIF2AK1) targets miR-122-3p. In addition, EIF2AK1 is highly expressed in patients with RA. In addition, EIF2AK1 activates the mTOR signaling pathway. miR-122-3p represses RA progression by reducing cell viability and increasing synoviocyte apoptosis.

Pinolenic acid exhibits anti-inflammatory and anti-atherogenic effects in peripheral blood-derived monocytes from patients with rheumatoid arthritis

Pinolenic acid (PNLA), an omega-6 polyunsaturated fatty acid from pine nuts, has anti-inflammatory and anti-atherogenic effects. We aimed to investigate the direct anti-inflammatory effect and anti-atherogenic effects of PNLA on activated purified CD14 monocytes from peripheral blood of patients with rheumatoid arthritis (RA) in vitro. Flow cytometry was used to assess the proportions of CD14 monocytes expressing TNF-α, IL-6, IL-1β, and IL-8 in purified monocytes from patients with RA after lipopolysaccharide (LPS) stimulation with/without PNLA pre-treatment. The whole genomic transcriptome (WGT) profile of PNLA-treated, and LPS-activated monocytes from patients with active RA was investigated by RNA-sequencing. PNLA reduced percentage of monocytes expressing cytokines: TNF-α by 23% (p = 0.048), IL-6 by 25% (p = 0.011), IL-1β by 23% (p = 0.050), IL-8 by 20% (p = 0.066). Pathway analysis identified upstream activation of peroxisome proliferator-activated receptors (PPARs), sirtuin3, and let7 miRNA, and KLF15, which are anti-inflammatory and antioxidative. In contrast, DAP3, LIF and STAT3, which are involved in TNF-α, and IL-6 signal transduction, were inhibited. Canonical Pathway analysis showed that PNLA inhibited oxidative phosphorylation (p = 9.14E−09) and mitochondrial dysfunction (p = 4.18E−08), while the sirtuin (SIRTs) signalling pathway was activated (p = 8.89E−06) which interfere with the pathophysiological process of atherosclerosis. Many miRNAs were modulated by PNLA suggesting potential post-transcriptional regulation of metabolic and immune response that has not been described previously. Multiple miRNAs target pyruvate dehydrogenase kinase-4 (PDK4), single-immunoglobulin interleukin-1 receptor molecule (SIGIRR), mitochondrially encoded ATP synthase membrane subunit 6 (MT-ATP6) and acetyl-CoA acyltranferase2 (ACAA2); genes implicated in regulation of lipid and cell metabolism, inflammation, and mitochondrial dysfunction. PNLA has potential anti-atherogenic and immune-metabolic effects on monocytes that are pathogenic in RA and atherosclerosis. Dietary PNLA supplementation regulates key miRNAs that are involved in metabolic, mitochondrial, and inflammatory pathways.

Thinking inside the box: Current insights into targeting orbital tissue remodeling and inflammation in thyroid eye disease

Thyroid eye disease (TED) is an autoimmune disorder that manifests in the orbit. In TED, the connective tissue behind the eye becomes inflamed and remodels with increased fat accumulation and/or increased muscle and scar tissue. As orbital tissue expands, patients develop edema, exophthalmos, diplopia, and optic neuropathy. In severe cases vision loss may occur secondary to corneal scarring from exposure or optic nerve compression. Currently there is no cure for TED, and treatments are limited. A major breakthrough in TED therapy occurred with the FDA approval of teprotumumab, a monoclonal insulin-like growth factor 1 receptor (IGF1R) blocking antibody. Yet, teprotumumab therapy has limitations, including cost, infusion method of drug delivery, variable response, and relapse. We describe approaches to target orbital fibroblasts and the complex pathophysiology that underlies tissue remodeling and inflammation driving TED. Further advances in the elucidation of the mechanisms of TED may lead to prophylaxis based upon early biomarkers as well as lead to more convenient, less expensive therapies.

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.

Identification of novel rheumatoid arthritis-associated MiRNA-204-5p from plasma exosomes

Rheumatoid arthritis (RA) is an autoimmune disease characterized by infiltration of immune cells in the synovium. However, the crosstalk of immune cells and synovial fibroblasts is still largely unknown. Here, global miRNA screening in plasma exosomes was carried out with a custom microarray (RA patients vs. healthy controls = 9:9). A total of 14 exosomal miRNAs were abnormally expressed in the RA patients. Then, downregulated expression of exosomal miR-204-5p was confirmed in both the replication (RA patients vs. healthy controls = 30:30) and validation groups (RA patients vs. healthy controls = 56:60). Similar to the findings obtained in humans, a decreased abundance of exosomal miR-204-5p was observed in mice with collagen-induced arthritis (CIA). Furthermore, Spearman correlation analysis indicated that plasma exosomal miR-204-5p expression was inversely correlated with disease parameters of RA patients, such as rheumatoid factor, erythrocyte sedimentation rate, and C-reactive protein. In vitro, our data showed that human T lymphocytes released exosomes containing large amounts of miR-204-5p, which can be transferred into synovial fibroblasts, inhibiting cell proliferation. Overexpression of miR-204-5p in synovial fibroblasts suppressed synovial fibroblast activation by targeting genes related to cell proliferation and invasion. In vivo assays found that administration of lentiviruses expressing miR-204-5p markedly alleviated the disease progression of the mice with CIA. Collectively, this study identified a novel RA-associated plasma exosomal miRNA-204-5p that mediates the communication between immune cells and synovial fibroblasts and can be used as a potential biomarker for RA diagnosis and treatment.

Analysis of Micro-RNA-144 Expression Profile in Patients with Multiple Sclerosis in Comparison with Healthy Individuals

BACKGROUND

Etiology of multiple sclerosis is non-clarified. It seems that environmental factors impact epigenetic in this disease. Micro-RNAs (MIR) as epigenetic factors are one of the most important factors in non-genetically neurodegenerative diseases. It has been found MIR-144 plays a main role in the regulation of many processes in the central nervous system. Here, we aimed to investigation of MIR-144 expression alteration in Multiple sclerosis (MS) patients.

METHODS

In this study 32 healthy and 32 MS patient's blood sample were analyzed by quantitative Real-Time PCR method and obtained data analyzed by REST 2009 software.

RESULTS

Analysis of Real-Time PCR data revealed that miR-144 Increase significantly in MS patients compared to healthy controls.

CONCLUSION

The increase of MIR-144 expression in MS patients is obvious. MIR-144 can be used as a biomarker of MS and help to early diagnosis and treatment of this disease.

Plasma expression of microRNA-425-5p and microRNA-451a as biomarkers of cardiovascular disease in rheumatoid arthritis patients

To validate in a cohort of 214 rheumatoid arthritis patients a panel of 10 plasmatic microRNAs, which we previously identified and that can facilitate earlier diagnosis of cardiovascular disease in rheumatoid arthritis patients. We identified 10 plasma miRs that were downregulated in male rheumatoid arthritis patients and in patients with acute myocardial infarction compared to controls suggesting that these microRNAs could be epigenetic biomarkers for cardiovascular disease in rheumatoid arthritis patients. Six of those microRNAs were validated in independent plasma samples from 214 rheumatoid arthritis patients and levels of expression were associated with surrogate markers of cardiovascular disease (carotid intima-media thickness, plaque formation, pulse wave velocity and distensibility) and with prior cardiovascular disease. Multivariate analyses adjusted for traditional confounders and treatments showed that decreased expression of microRNA-425-5p in men and decreased expression of microRNA-451 in women were significantly associated with increased (β = 0.072; p = 0.017) and decreased carotid intima-media thickness (β = -0.05; p = 0.013), respectively. MicroRNA-425-5p and microRNA-451 also increased the accuracy to discriminate patients with pathological carotid intima-media thickness by 1.8% (p = 0.036) in men and 3.5% (p = 0.027) in women, respectively. In addition, microRNA-425-5p increased the accuracy to discriminate male patients with prior cardiovascular disease by 3% (p = 0.008). Additionally, decreased expression of microRNA-451 was significantly associated with decreased pulse wave velocity (β = -0.72; p = 0.035) in overall rheumatoid arthritis population. Distensibility showed no significant association with expression levels of the microRNAs studied. We provide evidence of a possible role of microRNA-425-5p and microRNA-451 as useful epigenetic biomarkers to assess cardiovascular disease risk in patients with rheumatoid arthritis.

Preoperative serum circulating microRNAs as potential biomarkers for chronic postoperative pain after total knee replacement

Background

Chronic postoperative pain affects approximately 20% of patients with knee osteoarthritis after total knee replacement. Circulating microRNAs can be found in serum and might act as biomarkers in a variety of diseases. The current study aimed to investigate the preoperative expression of circulating microRNAs as potential predictive biomarkers for the development of chronic postoperative pain in the year following total knee replacement.

Methods

Serum samples, collected preoperatively from 136 knee osteoarthritis patients, were analyzed for 21 circulatory microRNAs. Pain intensity was assessed using a visual analog scale before and one year after total knee replacement. Patients were divided into a low-pain relief group (pain relief percentage <30%) and a high-pain relief group (pain relief percentage >30%) based on their pain relief one year after total knee replacement, and differences in microRNAs expression were analyzed between the two groups.

Results

We found that three microRNAs were preoperatively dysregulated in serum in the low-pain relief group compared with the high-pain relief group. MicroRNAs hsa-miR-146a-5p, -145-5p, and -130 b-3p exhibited fold changes of 1.50, 1.55, and 1.61, respectively, between the groups (all P values < 0.05). Hsa-miR-146a-5p and preoperative pain intensity correlated positively with postoperative pain relief (respectively, R = 0.300, P = 0.006; R = 0.500, P < 0.001).

Discussion

This study showed that patients with a low postoperative pain relief present a dysregulation of circulating microRNAs. Altered circulatory microRNAs expression correlated with postoperative pain relief, indicating that microRNAs can serve as predictive biomarkers of pain outcome after surgery and hence may foster new strategies for preventing chronic postoperative pain after total knee replacement (TKR).

ZFAS1 knockdown inhibits fibroblast-like synoviocyte proliferation, migration, invasion and inflammation, and promotes apoptosis via miR-3926/FSTL1 in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by joint disorders. Long non-coding RNA zinc finger antisense 1 (ZFAS1) is aberrantly expressed in numerous human diseases, including RA. The present study aimed to investigate the functions and underlying mechanisms of ZFAS1 in RA. Reverse transcription-quantitative PCR was performed to determine the expression levels of ZFAS1, microRNA (miR)-3926 and follistatin-like protein 1 (FSTL1). MTT assay, flow cytometric analysis and Transwell assay were performed to examine the proliferation, apoptosis, migration and invasion of fibroblast-like synoviocytes (FLSs), respectively. Western blotting was employed to measure the protein expression levels of cleaved caspase-3, interleukin (IL)-6, IL-1β, tumor necrosis factor-α and FSTL1. Dual-luciferase reporter assay was performed to verify the interaction between miR-3926 and ZFAS1 or FSTL1. The results demonstrated that ZFAS1 and FSTL1 were upregulated, and miR-3926 was downregulated in RA synovial tissues and RA-FLSs. ZFAS1 knockdown suppressed cell proliferation, migration, invasion and inflammatory cytokine production, and induced apoptosis in RA-FLSs. ZFAS1 acted as a sponge for miR-3926, and ZFAS1 overexpression abolished the impact of miR-3926 on the development of RA-FLSs. FSTL1 was a direct target of miR-3926, and the effect of FSTL1 knockdown on the progression of RA-FLSs was rescued by miR-3926 inhibition. Furthermore, ZFAS1 regulated FSTL1 expression levels via sponging miR-3926 in RA-FLSs. In conclusion, ZFAS1 knockdown inhibited RA-FLS proliferation, migration, invasion and inflammatory cytokine production, and induced apoptosis in RA via the miR-3926/FSTL1 axis.

Identification of differentially expressed microRNAs in primary esophageal achalasia by next-generation sequencing

Molecular knowledge regarding the primary esophageal achalasia is essential for the early diagnosis and treatment of this neurodegenerative motility disorder. Therefore, there is a need to find the main microRNAs (miRNAs) contributing to the mechanisms of achalasia. This study was conducted to determine some patterns of deregulated miRNAs in achalasia. This case-control study was performed on 52 patients with achalasia and 50 nonachalasia controls. The miRNA expression profiling was conducted on the esophageal tissue samples using the next-generation sequencing (NGS). Differential expression of miRNAs was analyzed by the edgeR software. The selected dysregulated miRNAs were additionally confirmed using the quantitative reverse transcription polymerase chain reaction (qRT-PCR). Fifteen miRNAs were identified that were significantly altered in the tissues of the patients with achalasia. Among them, three miRNAs including miR-133a-5p, miR-143-3p, and miR-6507-5p were upregulated. Also, six miRNAs including miR-215-5p, miR-216a-5p, miR-216b-5p, miR-217, miR-7641 and miR-194-5p were downregulated significantly. The predicted targets for the dysregulated miRNAs showed significant disease-associated pathways like neuronal cell apoptosis, neuromuscular balance, nerve growth factor signaling, and immune response regulation. Further analysis using qRT-PCR showed significant down-regulation of hsa-miR-217 (p-value = 0.004) in achalasia tissue. Our results may serve as a basis for more future functional studies to investigate the role of candidate miRNAs in the etiology of achalasia and their application in the diagnosis and probably treatment of the disease.

Serum Exosomal miRNA-1915-3p Is Correlated With Disease Activity of Korean Rheumatoid Arthritis

BACKGROUND/AIM

It has been found that microRNAs (miRNA) affect rheumatoid arthritis (RA) pathophysiology. This study aimed to identify novel serum exosomal miRNAs related to RA disease activity in patients with an inadequate treatment response.

PATIENTS AND METHODS

The sample population comprised clinical remission (CR) and non-clinical remission (non-CR) groups of RA patients. To identify potent miRNA markers for RA disease activity, miRNA array and qPCR were performed after patient serum exosomes preparation.

RESULTS

Has-miR-1915-3p and has-miR-6511b-5p were significantly higher in the serum exosomes of the CR group. The level of serum C-reactive protein (CRP) was negatively correlated with has-miR-1915-3p level in serum exosomes.

CONCLUSION

Has-miR-1915-3p may be a potential marker for Korean RA disease activity.

MicroRNA Interference in Hepatic Host-Pathogen Interactions

The liver is well recognized as a non-immunological visceral organ that is involved in various metabolic activities, nutrient storage, and detoxification. Recently, many studies have demonstrated that resident immune cells in the liver drive various immunological reactions by means of several molecular modulators. Understanding the mechanistic details of interactions between hepatic host immune cells, including Kupffer cells and lymphocytes, and various hepatic pathogens, especially viruses, bacteria, and parasites, is necessary. MicroRNAs (miRNAs), over 2600 of which have been discovered, are small, endogenous, interfering, noncoding RNAs that are predicted to regulate more than 15,000 genes by degrading specific messenger RNAs. Several recent studies have demonstrated that some miRNAs are associated with the immune response to pathogens in the liver. However, the details of the underlying mechanisms of miRNA interference in hepatic host-pathogen interactions still remain elusive. In this review, we summarize the relationship between the immunological interactions of various pathogens and hepatic resident immune cells, as well as the role of miRNAs in the maintenance of liver immunity against pathogens.

Epigenetics in Non-tumor Immune-Mediated Skin Diseases

Epigenetics is the study of the mechanisms that regulate gene expression without modifying DNA sequences. Knowledge of and evidence about how epigenetics plays a causative role in the pathogenesis of many skin diseases is increasing. Since the epigenetic changes present in tumor diseases have been thoroughly reviewed, we believe that knowledge of the new epigenetic findings in non-tumor immune-mediated dermatological diseases should be of interest to the general dermatologist. Hence, the purpose of this review is to summarize the recent literature on epigenetics in most non-tumor dermatological pathologies, focusing on psoriasis. Hyper- and hypomethylation of DNA methyltransferases and methyl-DNA binding domain proteins are the most common and studied methylation mechanisms. The acetylation and methylation of histones H3 and H4 are the most frequent and well-characterized histone modifications and may be associated with disease severity parameters and serve as therapeutic response markers. Many specific microRNAs dysregulated in non-tumor dermatological disease have been reviewed. Deepening the study of how epigenetic mechanisms influence non-tumor immune-mediated dermatological diseases might help us better understand the role of interactions between the environment and the genome in the physiopathogenesis of these diseases.

A Systems Biology Approach for miRNA-mRNA Expression Patterns Analysis in Rheumatoid Arthritis

Objective:

Considering the molecular complexity and heterogeneity of rheumatoid arthritis (RA), the identification of novel molecular contributors involved in RA initiation and progression using systems biology approaches will open up potential therapeutic strategies. The bioinformatics method allows the detection of associated miRNA-mRNA as both therapeutic and prognostic targets for RA.

Methods:

This research used a system biology approach based on a systematic re-analysis of the RA-related microarray datasets in the NCBI Gene Expression Omnibus (GEO) database to find out deregulated miRNAs. We then studied the deregulated miRNA-mRNA using Enrichr and Molecular Signatures Database (MSigDB) to identify novel RA-related markers followed by an overview of miRNA-mRNA interaction networks and RA-related pathways.

Results:

This research mainly focused on mRNA and miRNA interactions in all tissues and blood/serum associated with RA to obtain a comprehensive knowledge of RA. Recent systems biology approach analyzed seven independent studies and presented important RA-related deregulated miRNAs (miR-145-5p, miR-146a-5p, miR-155-5p, miR-15a-5p, miR-29c-3p, miR- 103a-3p, miR-125a-5p, miR-125b-5p, miR-218); upregulation of miR-125b is shown in the study (GSE71600). While the findings of the Enrichr showed cytokine and vitamin D receptor pathways and inflammatory pathways. Further analysis revealed a negative correlation between the vitamin D receptor (VDR) and miR-125b in RA-associated gene expression.

Conclusion:

Since vitamin D is capable of regulating the immune homeostasis and decreasing the autoimmune process through its receptor (VDR), it is regarded as a potential target for RA. According to the results obtained, a comparative correlation between negative expression of the vitamin D receptor (VDR) and miR-125b was suggested in RA. The increasing miR-125b expression would reduce the VitD uptake through its receptor.

MicroRNA-137-mediated inhibition of lysine-specific demethylase-1 prevents against rheumatoid arthritis in an association with the REST/mTOR axis

BACKGROUND

It has been increasingly reported that microRNAs (miRNAs) are related to rheumatoid arthritis (RA) pathogenesis. This present research was conducted to analyze the functions of miR-137 and the underlying molecular mechanism in RA progression.

METHODS

Differentially expressed miRNAs in RA patients were analyzed using microarray-based analyses. Next, experiments involving miR-137 overexpression were performed to analyze the role of miR-137 in human fibroblast-like synoviocytes-RA (HFLS-RA) using cell counting kit-8 (CCK-8) assay, EdU staining, Transwell assay and flow cytometry, respectively. The function of miR-137 in inflammation was determined using ELISA. The binding relationship between miR-137 and LSD1 was confirmed by dual-luciferase reporter gene assay and ChIP test. Besides, a rat model with RA was established for in vivo experiments.

RESULTS

miR-137 was downregulated in RA tissues and cells, which was negatively correlated with inflammatory factors. Upregulated miR-137 suppressed growth, migration and invasion of HFLS-RA, but promoted apoptosis. Lysine-specific demethylase-1 (LSD1) was a target of miR-137 and could be negatively regulated by miR-137. Moreover, LSD1 could activate REST through demethylation, while the REST/mTOR pathway induced levels of pro-inflammatory factors in RA. We observed the similar results in our in vivo study.

CONCLUSION

This study suggested that miR-137 reduced LSD1 expression to inhibit the activation of REST/mTOR pathway, thus preventing against inflammation and ameliorating RA development. Our research may offer new insights into treatment of RA.

Flåm S, Leithaug M, Dalland M, Rayner S, Lie BA, Gilfillan GD. An extension to: Systematic assessment of commercially available low-input miRNA library preparation kits

High-throughput sequencing has emerged as the favoured method to study microRNA (miRNA) expression, but biases introduced during library preparation have been reported. We recently compared the performance (sensitivity, reliability, titration response and differential expression) of six commercially-available kits on synthetic miRNAs and human RNA, where library preparation was performed by the vendors. We hereby supplement this study with data from two further commonly used kits (NEBNext, NEXTflex) whose manufacturers initially declined to participate. NEXTflex demonstrated the highest sensitivity, which may reflect its use of partially-randomized adapter sequences, but overall performance was lower than the QIAseq and TailorMix kits. NEBNext showed intermediate performance. We reaffirm that biases are kit specific, complicating the comparison of miRNA datasets generated using different kits.

MicroRNA-340-5p suppressed rheumatoid arthritis synovial fibroblast proliferation and induces apoptotic cell number by targeting signal transducers and activators of transcription 3

Rheumatoid arthritis is a chronic systemic autoimmune disease. In this study, the role of microRNA-340-5p in rheumatoid arthritis was investigated. qRT-PCR was used to detect the expression of microRNA-340-5p in serums, synovial tissues, and fibroblast-like synoviocytes from patients and healthy participants. Cell proliferation rate, cell cycle and apoptotic cell numbers were measured by CCK-8 and flow cytometry assays. The expression of pro-inflammation factors was determined by ELISA. Our data showed that the expression of microRNA-340-5p was greatly suppressed in rheumatoid arthritis serums, synovial tissues and rheumatoid arthritis-fibroblast-like synoviocytes compared to that in healthy controls. Over-expression of microRNA-340-5p greatly suppressed cell proliferation, promoted cell apoptosis, and suppressed the expression of inflammation factors in rheumatoid arthritis fibroblast-like synoviocytes. Additionally, STAT3 was a target of microRNA-340-5. Overexpression of STAT3 could reverse the outcome of microRNA-340-5p on cell proliferation and apoptosis in rheumatoid arthritis fibroblast-like synoviocytes. The findings in our study demonstrated that microRNA-340-5p may serve as a potential target for therapeutic direction for patients with rheumatoid arthritis.

Exosomal miRNA-486-5p derived from rheumatoid arthritis fibroblast-like synoviocytes induces osteoblast differentiation through the Tob1/BMP/Smad pathway

The pathogenesis of rheumatoid arthritis (RA) is related to the inhibition of osteoblast differentiation. Exosomes secreted from RA fibroblast-like synoviocytes (RA-FLSs-exos) are associated with the pathogenesis of RA and microRNAs (miRNAs) being crucial for RA progression. Accordingly, the aim of the present study is to elucidate the effect of RA-FLS-derived exosomes on osteoblast differentiation and further identify exosomal cargos responsible for this effect. RA-FLSs were isolated from a RA patient and osteoblasts from the donor bone. Isolated RA-FLSs-exos were co-cultured with osteoblasts. Osteoblast differentiation was evaluated by ALP quantification assays, Alizarin Red S staining, and determining markers of osteoblast activity (Osx, OC, Col1a1 and Dlx2). Collagen induced arthritis (CIA)-induced mouse models were established. RA-FLSs-exo could be phagocytosed by osteoblasts. Elevating the expression of miR-486-5p in RA-FLSs-exo promoted osteoblast differentiation. miR-486-5p targeted Tob1 and activated the BMP/Smad signaling pathway in osteoblasts. In addition, RA-FLSs-exo containing miR-486-5p facilitated osteoblast differentiation by activating the BMP/Smad signaling pathway and repressing Tob1. Moreover, RA-FLSs-exo containing miR-486-5p alleviated the disease severity of RA by decreasing Tob1 expression in CIA-induced mice. To sum up, RA-FLSs-exo carrying miR-486-5p serve as a promoter for osteoblast differentiation in RA, ultimately highlighting a promising competitive new target for RA treatment.

The Role of Circulating MicroRNA in Glioblastoma Liquid Biopsy

Glioblastoma multiforme (GBM) is the most common and aggressive primary malignancy of the central nervous system. The standard used to monitor disease progression and therapeutic response has been magnetic resonance imaging, which is usually obtained preoperatively and postoperatively. Patients with GBM are monitored every 2-3 months and scans are repeated until progression is detected. Sometimes there is an inability to detect tumor progression or difficulty in differentiating tumor progression from pseudoprogression. With the difficulty of distinguishing disease progression, as well as the cost of imaging, there may be a need for the existence of a noninvasive liquid biopsy. There is no reliable biomarker for GBM that can be used for liquid biopsy, but if one could be detected in serum or cerebrospinal fluid and vary with tumor burden, then, it could be developed into one. MicroRNAs (miRNAs) are short, single-stranded, noncoding RNAs that posttranscriptionally control gene expression. They play vital roles in tumor progression, migration, invasion, and stemness. Because miRNAs are secreted in stable forms in bodily fluid, either via extracellular vesicles or in cell-free form, they have great potential as biomarkers that can be used for liquid biopsy. Various miRNAs that are dysregulated in GBM have been identified in tissue, cerebrospinal fluid, and serum samples. There needs to be standardization of sample collection and quantification for both cell-free and exosomal-derived samples. Further studies need to be performed on larger cohorts to evaluate the sensitivity and specificity of not just miRNAs but most potential biomarkers.

miR-221-3p Drives the Shift of M2-Macrophages to a Pro-Inflammatory Function by Suppressing JAK3/STAT3 Activation

Objectives: Macrophages are conventionally classified as pro-inflammatory (M1) and anti-inflammatory (M2) functional types. There is evidence for a predominance of macrophages with an inflammatory phenotype (M1) in the rheumatoid arthritis (RA) synovium. MicroRNAs (miRs) play a pivotal role in regulating the inflammatory response in innate immune cells and are found at dysregulated levels in RA patients. Here we explored miRs that tune the inflammatory function of M2-macrophages.

Methods: Expression profiles of miR-221-3p and miR-155-5p were analyzed in clinical samples from RA, other inflammatory arthritis (OIA), osteoarthritis (OA), and healthy donors (HD) by qPCR. In vitro generated macrophages were transfected with miR-mimics and inhibitors. Transcriptome profiling through RNA-sequencing was performed on M2-macrophages overexpressing miR-221-3p mimic with or without LPS treatment. Secretion of IL-6, IL-10, IL-12, IL-8, and CXCL13 was measured in M1- and M2-macrophages upon TLR2/TLR3/TLR4-stimulation using ELISA. Inflammatory pathways including NF-κB, IRF3, MAPKs, and JAK3/STAT3 were evaluated by immunoblotting. Direct target interaction of miR-221-3p and predicted target sites in 3'UTR of JAK3 were examined by luciferase reporter gene assay.

Results: miR-221-3p in synovial tissue and fluid was increased in RA vs. OA or OIA. Endogenous expression levels of miR-221-3p and miR-155-5p were higher in M1- than M2-macrophages derived from RA patients or HD. TLR4-stimulation of M1- and M2-macrophages resulted in downregulation of miR-221-3p, but upregulation of miR-155-5p. M2-macrophages transfected with miR-221-3p mimics secreted less IL-10 and CXCL13 but more IL-6 and IL-8, exhibited downregulation of JAK3 protein and decreased pSTAT3 activation. JAK3 was identified as new direct target of miR-221-3p in macrophages. Co-transfection of miR-221-3p/miR-155-5p mimics in M2-macrophages increased M1-specific IL-12 secretion.

Conclusions: miR-221-3p acts as a regulator of TLR4-induced inflammatory M2-macrophage function by directly targeting JAK3. Dysregulated miR-221-3p expression, as seen in synovium of RA patients, leads to a diminished anti-inflammatory response and drives M2-macrophages to exhibit a M1-cytokine profile.

Role of Host and Pathogen-Derived MicroRNAs in Immune Regulation During Infectious and Inflammatory Diseases

MicroRNAs (miRNAs, miRs) are short, endogenously initiated, non-coding RNAs that bind to target mRNAs, leading to the degradation or translational suppression of respective mRNAs. They have been reported as key players in physiological processes like differentiation, cellular proliferation, development, and apoptosis. They have gained importance as gene expression regulators in the immune system. They control antibody production and release various inflammatory mediators. Abnormal expression and functioning of miRNA in the immune system is linked to various diseases like inflammatory disorders, allergic diseases, cancers etc. As compared to the average human genome, miRNA targets the genes of immune system quite differently. miRNA appeared to regulate the responses related to both acquired and innate immunity of the humans. Several miRNAs importantly regulate the transcription and even, dysregulation of inflammation-related mediators. Many miRNAs are either upregulated or downregulated in various inflammatory and infectious diseases. Hence, modifying or targeting the expression of miRNAs might serve as a novel strategy for the diagnosis, prevention, and treatment of various inflammatory and infectious conditions.

miR‑760 regulates skeletal muscle proliferation in rheumatoid arthritis by targeting Myo18b

MicroRNAs serve an important role in the development of several diseases. Numerous genes regulate the skeletal muscle differentiation of C2C12 myoblasts. The role of miR-760 in rheumatoid arthritis (RA) has not been reported, to the best of our knowledge. Therefore, the aim of the present study was to examine the role of miR-760 in regulating skeletal muscle proliferation in RA. Potential genes functionally involved in the tarsal joint of a collagen-induced RA model were identified using Gene Expression Omnibus. Reverse transcription-quantitative PCR and western blot analyses were performed to determine the mRNA and protein expression levels. The proliferation, cell cycle progression and migration of C2C12 myoblasts were detected using Cell Counting Kit-8, flow cytometry and wound-healing assays, respectively. TargetScan was used to predict the potential target genes of miR-760, and this was verified using a dual-luciferase reporter assay. In the present study, myosin-18b (Myo18b) expression was determined to be downregulated in the RA model. Silencing Myo18b decreased the proliferation, abrogated the cell cycle progression, and reduced the migration and differentiation of C2C12 myoblasts. Expression levels of cyclin-dependent kinase 2, cyclin D1, matrix metalloproteinase (MMP)-2, MMP-9, myogenin and myosin heavy chain 6 were all decreased when Myo18b was silenced. Furthermore, overexpression of Myo18b induced opposing effects on C2C12 myoblasts. It was shown that Myo18b was a target gene of miRNA-760. Overexpression of miR-760 decreased proliferation, cell cycle progression, migration and differentiation in C2C12 myoblasts, and decreased the expression of Myo18b. The opposite results were observed when miR-760 was downregulated. In conclusion, miR-760 inhibited proliferation and differentiation by targeting Myo18b in C2C12 myoblasts. The results of the present study may contribute to understanding the mechanisms underlying RA skeletal muscle proliferation, and miR-760/Myo18b may serve as potential targets for treating patients with RA.

Systematic assessment of commercially available low-input miRNA library preparation kits

High-throughput sequencing is increasingly favoured to assay the presence and abundance of microRNAs (miRNAs) in biological samples, even from low RNA amounts, and a number of commercial vendors now offer kits that allow miRNA sequencing from sub-nanogram (ng) inputs. Although biases introduced during library preparation have been documented, the relative performance of current reagent kits has not been investigated in detail. Here, six commercial kits capable of handling <100ng total RNA input were used for library preparation, performed by kit manufactures, on synthetic miRNAs of known quantities and human total RNA samples. We compared the performance of miRNA detection sensitivity, reliability, titration response and the ability to detect differentially expressed miRNAs. In addition, we assessed the use of unique molecular identifiers (UMI) sequence tags in one kit. We observed differences in detection sensitivity and ability to identify differentially expressed miRNAs between the kits, but none were able to detect the full repertoire of synthetic miRNAs. The reliability within the replicates of all kits was good, while larger differences were observed between the kits, although none could accurately quantify the relative levels of the majority of miRNAs. UMI tags, at least within the input ranges tested, offered little advantage to improve data utility. In conclusion, biases in miRNA abundance are heavily influenced by the kit used for library preparation, suggesting that comparisons of datasets prepared by different procedures should be made with caution. This article is intended to assist researchers select the most appropriate kit for their experimental conditions.

Analysis of gene expression in rheumatoid arthritis and related conditions offers insights into sex-bias, gene biotypes and co-expression patterns

The era of next-generation sequencing has mounted the foundation of many gene expression studies. In rheumatoid arthritis research, this has led to the discovery of important candidate genes which offered novel insights into mechanisms and their possible roles in the cure of the disease. In the last years, data generation has outstripped data analysis and while many studies focused on specific aspects of the disease, a global picture of the disease is not yet accomplished. Here, we analyzed and compared a collection of gene expression information from healthy individuals and from patients suffering under different arthritis conditions from published studies containing the following clinical conditions: early and established rheumatoid arthritis, osteoarthritis and arthralgia. We show comprehensive overviews of this data collection and give new insights specifically on gene expression in the early stage, into sex-dependent gene expression, and we describe general differences in expression of different biotypes of genes. Many genes that are related to cytoskeleton changes (actin filament related genes) are differently expressed in early rheumatoid arthritis in comparison to healthy subjects; interestingly, eight of these genes reverse their expression ratio significantly between men and women compared early rheumatoid arthritis and healthy subjects. There are some slighter changes between men and woman between the conditions early and established rheumatoid arthritis. Another aspect are miRNAs and other gene biotypes which are not only promising candidates for diagnoses but also change their expression grossly in average at rheumatoid arthritis and arthralgia compared to the healthy condition. With a selection of intersecting genes, we were able to generate simple classification models to distinguish between healthy and rheumatoid arthritis as well as between early rheumatoid arthritis to other arthritides based on gene expression.

Down-regulation of microRNA-142-3p inhibits the aggressive phenotypes of rheumatoid arthritis fibroblast-like synoviocytes through inhibiting nuclear factor-κB signaling

The present study aimed to investigate the regulatory roles of miR-142-3p on the aggressive phenotypes of rheumatoid arthritis (RA) human fibroblast-like synoviocytes (RA-HFLSs), and reveal the potential mechanisms relating with nuclear factor-κB (NF-κB) signaling. miR-142-3p expression was detected in RA synovial tissues and RA-HFLSs by quantitative real-time PCR (qRT-PCR) and Northern blot analysis. RA-HFLSs were transfected with miR-142-3p inhibitor and/or treated with 10 µg/l tumor necrosis factor α (TNF-α). The viability, colony formation, apoptosis, migration, invasion, and the levels of interleukin (IL)-6, and matrix metalloproteinase 3 (MMP-3) were detected. The mRNA expressions of B-cell lymphoma-2 (Bcl-2), Bax, Bad, IL-6, and MMP-3 were detected by qRT-PCR. Moreover, the expression of Bcl-2, IL-1 receptor-associated kinase 1 (IRAK1), Toll-like receptor 4 (TLR4), NF-κB p65, and phosphorylated NF-κB p65 (p-NF-κB p65) were detected by Western blot. The interaction between IRAK1 and miR-142-3p was identified by dual luciferase reporter gene assay. MiR-142-3p was up-regulated in RA synovial tissues and RA-HFLSs. TNF-α activated the aggressive phenotypes of RA-HFLSs, including enhanced proliferation, migration, invasion, and inflammation, and inhibited apoptosis. miR-142-3p inhibitor significantly decreased the cell viability, the number of cell clones, the migration rate, the number of invasive cells, the contents and expression of IL-6 and MMP-3, and increased the apoptosis rate and the expressions of Bax and Bad, and decreased Bcl-2 expression of TNF-α-treated RA-HFLSs. MiR-142-3p inhibitor significantly reversed TNF-α-induced up-regulation of IRAK1, TLR4, and p-NF-κB p65 in TNF-α-treated RA-HFLSs. Besides, IRAK1 was a target of miR-142-3p. The down-regulation of miR-142-3p inhibited the aggressive phenotypes of RA-HFLSs through inhibiting NF-κB signaling.

MicroRNA and exosome: Key players in rheumatoid arthritis

Rheumatoid arthritis (RA) is known as one of important autoimmune disorders which can lead to joint pain and damage throughout body. Given that internal (ie, genetic and epigenetic alterations) and external factors (ie, lifestyle changes, age, hormones, smoking, stress, and obesity) involved in RA pathogenesis. Increasing evidence indicated that cellular and molecular alterations play critical roles in the initiation and progression of RA. Among various targets and molecular signaling pathways, microRNAs (miRNAs) and their regulatory networks have key roles in the RA pathogenesis. It has been showed that deregulation of many miRNAs involved in different stages of RA. Hence, identification of miRNAs and their signaling pathways in RA, could contribute to new knowledge which help to better treatment of patients with RA. Besides miRNAs, exosomes have been emerged as key messengers in RA pathogenesis. Exsosomes are nanocarriers which could be released from various cells and lead to changing of behaviors recipient cells via targeting their cargos (eg, proteins, messenger RNAs, miRNAs, long noncoding RNAs, DNAs). Here, we summarized several miRNAs involved in RA pathogenesis. Moreover, we highlighted the roles of exosomes in RA pathogenesis.

Plasma MicroRNAs in Established Rheumatoid Arthritis Relate to Adiposity and Altered Plasma and Skeletal Muscle Cytokine and Metabolic Profiles

Background: MicroRNAs have been implicated in the pathogenesis of rheumatoid arthritis (RA), obesity, and altered metabolism. Although RA is associated with both obesity and altered metabolism, expression of RA-related microRNA in the setting of these cardiometabolic comorbidities is unclear. Our objective was to determine relationships between six RA-related microRNAs and RA disease activity, inflammation, body composition, and metabolic function. Methods: Expression of plasma miR-21, miR-23b, miR-27a, miR-143, miR-146a, and miR-223 was measured in 48 persons with seropositive and/or erosive RA (mean DAS-28-ESR 3.0, SD 1.4) and 23 age-, sex-, and BMI-matched healthy controls. Disease activity in RA was assessed by DAS-28-ESR. Plasma cytokine concentrations were determined by ELISA. Body composition was assessed using CT scan to determine central and muscle adipose and thigh muscle tissue size and tissue density. Plasma and skeletal muscle acylcarnitine, amino acid, and organic acid metabolites were measured via mass-spectroscopy. Plasma lipoproteins were measured via nuclear magnetic resonance (NMR) spectroscopy. Spearman correlations were used to assess relationships for microRNA with inflammation and cardiometabolic measures. RA and control associations were compared using Fisher transformations. Results: Among RA subjects, plasma miR-143 was associated with plasma IL-6 and IL-8. No other RA microRNA was positively associated with disease activity or inflammatory markers. In RA, microRNA expression was associated with adiposity, both visceral adiposity (miR-146a, miR-21, miR-23b, and miR-27a) and thigh intra-muscular adiposity (miR-146a and miR-223). RA miR-146a was associated with greater concentrations of cardiometabolic risk markers (plasma short-chain dicarboxyl/hydroxyl acylcarnitines, triglycerides, large VLDL particles, and small HDL particles) and lower concentrations of muscle energy substrates (long-chain acylcarnitines and pyruvate). Despite RA and controls having similar microRNA levels, RA, and controls differed in magnitude and direction for several associations with cytokines and plasma and skeletal muscle metabolic intermediates. Conclusion: Most microRNAs thought to be associated with RA disease activity and inflammation were more reflective of RA adiposity and impaired metabolism. These associations show that microRNAs in RA may serve as an epigenetic link between RA inflammation and cardiometabolic comorbidities.

Micro-RNA-96 and interleukin-10 are independent biomarkers for multiple sclerosis activity

BACKGROUND

Micro-RNAs (miRNAs) are evolving as biological markers for multiple sclerosis (MS) both in activity and remission. miR-96 is associated with remission, however, the exact mechanism through which it contributes to the anti-inflammatory pathway is not clear.

OBJECTIVE

To study the expression of miR-96 and IL-10 (anti-inflammatory mediator) in relapsing remitting (RR) MS.

SUBJECTS AND METHODS

A case control study including 32 RRMS patients from Kasr Al-Ainy MS clinic, Cairo University, Egypt, and 26 healthy controls (HC). Assessment of serum IL-10 by ELISA, and miR-96 via real time PCR was done during relapse and remission in patients, and in HC.

RESULTS

IL-10 was higher in RRMS patients during remission and in HC compared with relapse (P ˂ 0.001). miR-96 expression was higher in RRMS patients during remission compared with relapse and HC, and was higher in HC than in relapse (P ˂ 0.001). IL-10 level in remission correlated positively with disease duration (r = 0.41; P = 0.02). Otherwise, no correlation was found between IL-10 and relapse number or EDSS (P>0.05). miR-96 in relapse negatively correlated with EDSS in relapse (r=-0.47; P=0.007), but no correlation was found with disease duration or relapse number, whereas, miR-96 in remission did not correlate with any clinical parameters (P>0.05). No correlation was found between IL-10 and miR-96 either in relapse or remission (P>0.05).

CONCLUSION

IL-10 and miR-96 are associated with MS quiescence, however, the lack of a significant correlation between them implicates that the influence of miR-96 may be exhibited through some pathway other than IL-10.

A Protocol To Characterize Peptide-Based Drug Delivery Systems for miRNAs

Micro RNA (miRNA)-based medicines have attracted attention as new therapeutic strategies to treat genetic diseases and metabolic and immunological disorders. MiRNAs have emerged as key mediators of metabolic processes fulfilling regulatory functions in maintaining physiological conditions, while altered miRNA expression profiles are often associated with genetic diseases. However, naked miRNAs exhibit poor enzymatic stability, biomembrane permeation, and cellular uptake. To overcome these limitations, the development of appropriate drug delivery systems (DDS) is necessary. Herein, a DDS is characterized being assembled from miRNA-27a (negative regulator in fat metabolism) and the amphipathic N-TER peptide. Dynamic light scattering (DLS), electrophoretic light scattering, and atomic force microscopy (AFM) are used to investigate physicochemical properties (i.e., size, shape, and charge) of the DDS. Although surface charges should provide decent stabilization, the AFM results confirm a state of agglomeration, which is also suggested by DLS. Furthermore, AFM studies reveal adhesion on hydrophilic as well as hydrophobic substrates, which is related to the amphipathic properties of the N-TER peptide. Physicochemical properties of DDS are important parameters, which have an impact on cell internalization/uptake and have to be taken into account for in vitro studies to develop a successful peptide-based DDS for miRNA replacement therapy in metabolic diseases, such as obesity and others.

Immunopathogenic Mechanisms and Novel Immune-Modulated Therapies in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic, inflammatory autoimmune disease of unknown etiology. It is characterized by the presence of rheumatoid factor and anticitrullinated peptide antibodies. The orchestra of the inflammatory process among various immune cells, cytokines, chemokines, proteases, matrix metalloproteinases (MMPs), and reactive oxidative stress play critical immunopathologic roles in the inflammatory cascade of the joint environment, leading to clinical impairment and RA. With the growing understanding of the immunopathogenic mechanisms, increasingly novel marked and potential biologic agents have merged for the treatment of RA in recent years. In this review, we focus on the current understanding of pathogenic mechanisms, highlight novel biologic disease-modifying antirheumatic drugs (DMRADs), targeted synthetic DMRADs, and immune-modulating agents, and identify the applicable immune-mediated therapeutic strategies of the near future. In conclusion, new therapeutic approaches are emerging through a better understanding of the immunopathophysiology of RA, which is improving disease outcomes better than ever.

An Updated Meta-Analysis of the Associations Between MicroRNA Polymorphisms and Susceptibility to Rheumatoid Arthritis

Aims: Rheumatoid arthritis (RA) is characterized by cartilage and bone damage leading to disability. Here, the association between microRNA (miRNA) polymorphisms and susceptibility to RA was evaluated by performing an updated meta-analysis and systematic review.

Main methods: An electronic search of databases including PubMed and Embase was performed from inception to December 8, 2017 to retrieve studies investigating the association between miRNA polymorphisms and RA risk. Two reviewers independently screened literature according to the inclusion and exclusion criteria and extracted data. The meta-analysis was conducted using Stata 14.0 software.

Key findings: Thirteen case-control studies with 2660 cases and 4098 controls were screened out after a systematic search. One study from the miR-146a rs2910164 G > C polymorphism group and two from the miR-499 rs3746444 T > C polymorphism group were excluded because of deviations from Hardy-Weinberg equilibrium. Pooled analysis demonstrated that miR-146a rs2910164 G > C polymorphism was not significantly associated with susceptibility to RA. However, a significant association was observed between miR-499 rs3746444 T > C polymorphism and RA risk (C vs. T: OR = 1.22, 95% CI = 1.05–1.42, P = 0.008; TC vs. TT: OR = 1.26, 95% CI = 1.05–1.50, P = 0.011; TC/CC vs. TT: OR = 1.26, 95% CI = 1.07–1.5, P = 0.007). Subgroup analysis based on ethnicity showed no significant association between miR-499 T > C polymorphism and susceptibility to RA in the Asian population (P > 0.05). However, in Caucasian population, the C allele in the miR-499 T > C polymorphism was a contributor to RA susceptibility in some genetic models (C vs. T: OR = 1.64, 95% CI = 1.28–2.11, P < 0.001; TC vs. TT: OR = 1.95, 95% CI = 1.40–2.71, P < 0.001; TC/CC vs. TT: OR = 1.96, 95% CI = 1.43–2.69, P < 0.001).

Significance: The miR-146a rs2910164 G > C polymorphism was not associated with susceptibility to RA. In the Caucasian population, the C allele in the miR-499 T > C polymorphism contributed to RA susceptibility.

MicroRNA-small molecule association identification: from experimental results to computational models

Small molecule is a kind of low molecular weight organic compound with variety of biological functions. Studies have indicated that small molecules can inhibit a specific function of a multifunctional protein or disrupt protein-protein interactions and may have beneficial or detrimental effect against diseases. MicroRNAs (miRNAs) play crucial roles in cellular biology, which makes it possible to develop miRNA as diagnostics and therapeutic targets. Several drug-like compound libraries were screened successfully against different miRNAs in cellular assays further demonstrating the possibility of targeting miRNAs with small molecules. In this review, we summarized the concept and functions of small molecule and miRNAs. Especially, five aspects of miRNA functions were exhibited in detail with individual examples. In addition, four disease states that have been linked to miRNA alterations were summed up. Then, small molecules related to four important miRNAs miR-21, 122, 4644 and 27 were selected for introduction. Some important publicly accessible databases and web servers of the experimentally validated or potential small molecule-miRNA associations were discussed. Identifying small molecule targeting miRNAs has become an important goal of biomedical research. Thus, several experimental and computational models have been developed and implemented to identify novel small molecule-miRNA associations. Here, we reviewed four experimental techniques used in the past few years to search for small-molecule inhibitors of miRNAs, as well as three types of models of predicting small molecule-miRNA associations from different perspectives. Finally, we summarized the limitations of existing methods and discussed the future directions for further development of computational models.

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

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

RETRACTED: Tanshinone IIA protects murine chondrogenic ATDC5 cells from lipopolysaccharide-induced inflammatory injury by down-regulating microRNA-203a

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief. Concerns were raised about the background pattern of the Western Blots from Figures 3 and 5-7. Given the comments of Dr Elisabeth Bik regarding this article “This paper belongs to a set of over 400 papers (as per February 2020) that share very similar Western blots with tadpole-like shaped bands, the same background pattern, and striking similarities in title structures, paper layout, bar graph design, and - in a subset - flow cytometry panels”, the journal requested the authors to provide the raw data. However, the authors were not able to provide raw data of sufficient quality and detail for the journal to independently audit the provenance and validity of the data, and therefore the Editor-in-Chief decided to retract the article.

The expression of Mirc1/Mir17-92 cluster in sputum samples correlates with pulmonary exacerbations in cystic fibrosis patients

INTRODUCTION

Cystic fibrosis (CF) is a multi-organ disorder characterized by chronic sino-pulmonary infections and inflammation. Many patients with CF suffer from repeated pulmonary exacerbations that are predictors of worsened long-term morbidity and mortality. There are no reliable markers that associate with the onset or progression of an exacerbation or pulmonary deterioration. Previously, we found that the Mirc1/Mir17-92a cluster which is comprised of 6 microRNAs (Mirs) is highly expressed in CF mice and negatively regulates autophagy which in turn improves CF transmembrane conductance regulator (CFTR) function. Therefore, here we sought to examine the expression of individual Mirs within the Mirc1/Mir17-92 cluster in human cells and biological fluids and determine their role as biomarkers of pulmonary exacerbations and response to treatment.

METHODS

Mirc1/Mir17-92 cluster expression was measured in human CF and non-CF plasma, blood-derived neutrophils, and sputum samples. Values were correlated with pulmonary function, exacerbations and use of CFTR modulators.

RESULTS

Mirc1/Mir17-92 cluster expression was not significantly elevated in CF neutrophils nor plasma when compared to the non-CF cohort. Cluster expression in CF sputum was significantly higher than its expression in plasma. Elevated CF sputum Mirc1/Mir17-92 cluster expression positively correlated with pulmonary exacerbations and negatively correlated with lung function. Patients with CF undergoing treatment with the CFTR modulator Ivacaftor/Lumacaftor did not demonstrate significant change in the expression Mirc1/Mir17-92 cluster after six months of treatment.

CONCLUSIONS

Mirc1/Mir17-92 cluster expression is a promising biomarker of respiratory status in patients with CF including pulmonary exacerbation.