Altered expression of microRNAs may predict therapeutic response in rheumatoid arthritis patients

Prevention of rheumatoid arthritis using a familial predictive medicine approach

Most of the chronic-degenerative diseases deserve a very early recognition of symptoms and signs for the earliest secondary prevention, which could be also very useful in many cases for the most precocious clinical approach. The periodic monitoring of a subject at risk of a specific disease, because of genomic predisposition by predictive medicine approach, may help to earlier detection of onset and/or the progression of the pathology itself, through intra-individual monitoring. This is particularly the case of rheumatoid arthritis (RA) for which an early diagnosis is undoubtedly the first step to ensure the most proper therapy for the patient. Thus, the earlier identification of individuals at high risk of RA could lead to ultra-preventive strategies to start for the best lifestyle performances and/or for any other effective therapeutic interventions to contrast the onset, and/or the evolution of the putative RA. This will also optimize both costs and medical resources, according to the health care policies of many countries.

miR-21 attenuated inflammation targeting MyD88 in human chondrocytes stimulated with Hyaluronan oligosaccharides

Inflammation is the body's response to injuries, which depends on numerous regulatory factors. Among them, miRNAs have gained much attention for their role in regulating inflammatory gene expression at multiple levels. In particular, miR-21 is up-regulated during the inflammatory response and reported to be involved in the resolution of inflammation by down-regulating pro-inflammatory mediators, including MyD88. Herein, we evaluated the regulatory effects of miR-21 on the TLR-4/MyD88 pathway in an in vitro model of 6-mer HA oligosaccharides-induced inflammation in human chondrocytes. The exposition of chondrocytes to 6-mer HA induced the activation of the TLR4/MyD88 pathway, which culminates in NF-kB activation. Changes in miR-21, TLR-4, MyD88, NLRP3 inflammasome, IL-29, Caspase1, MMP-9, iNOS, and COX-2 mRNA expression of 6-mer HA-stimulated chondrocytes were examined by qRT-PCR. Protein amounts of TLR-4, MyD88, NLRP3 inflammasome, p-ERK1/2, p-AKT, IL-29, caspase1, MMP-9, p-NK-kB p65 subunit, and IKB-a have been evaluated by ELISA kits. NO and PGE2 levels have been assayed by colorimetric and ELISA kits, respectively. HA oligosaccharides induced a significant increase in the expression of the above parameters, including NF-kB activity. The use of a miR-21 mimic attenuated MyD88 expression levels and the downstream effectors. On the contrary, treatment with a miR-21 inhibitor induced opposite effects. Interestingly, the use of a MyD88 siRNA confirmed MyD88 as the target of miR-21 action. Our results suggest that miR-21 expression could increase in an attempt to reduce the inflammatory response, targeting MyD88.

MicroRNA -21 expression as an auxiliary diagnostic biomarker of acute brucellosis

BACKGROUND

This study aimed to measure the expression levels of peripheral blood miRNAs in brucellosis and their involvement in the different phases of the brucellosis.

METHODS

The expression levels of miRNAs including miR-210, miR-155, miR-150, miR-146a, miR-139-3p, miR-125a-5p, miR-29 and miR-21 were quantified in 57 brucellosis patients subgrouped into acute, under treatment & relapse phase and 30 healthy controls (HCs) using real-time polymerase chain reaction (RT-PCR). The receiver operating characteristic (ROC) analysis curve analysis was performed to find a biomarker for discrimination of different phases of brucellosis.

RESULTS

The expression of miR-155, miR-146a, miR-125a-5p, miR-29, and miR-21 was found to be elevated in the acute brucellosis patients compared to HCs. miR-29 changed in under-treatment patients, while miR-139-3p and miR-125a-5p showed alterations in relapse cases. The ROC curve analysis depicted the potential involvement of miR-21 in the pathogenesis of acute brucellosis.

CONCLUSION

The expression level of miR-21 is significantly augmented in acute brucellosis and has the potential to be a contributing diagnostic factor for acute infection.

Overexpression of Synoviolin and miR-125a-5p, miR-19b-3p in peripheral blood of rheumatoid arthritis patients after treatment with conventional DMARDs and methylprednisolone

PURPOSE

SYVN1 is an endoplasmic reticulum (ER)-resident E3 ubiquitin ligase that has an essential function along with SEL1L in rheumatoid arthritis (RA) pathogenesis. This study aimed to investigate the changes in the expression of peripheral blood ncRNAs and SYVN1-SEL1L affected by DMARDs treatment.

METHODS

Twenty-five newly diagnosed RA patients were randomly assigned to receive conventional DMARDs (csDMARDs) and methylprednisolone for six months. The peripheral blood gene expression of SYVN1 and SEL1L and possible regulatory axes, NEAT1, miR-125a-5p, and miR-19b-3p, were evaluated before and after qRT-PCR. We also compared differences between the patients and healthy controls (HCs), and statistical analyses were performed to determine the correlation between ncRNAs with SYVN1-SEL1L and the clinical parameters of RA.

RESULTS

Expression of NEAT1 (P = 0.0001), miR-19b-3p (P = 0.007), miR-125a-5p (P = 0.005), and SYVN1 (P = 0.036) was significantly increased in newly diagnosed patients compared to HCs; also, miR-125a-5p, miR-19b-3p, and SYVN1 were significantly overexpressed after treatment (P = 0.001, P = 0.001, and P = 0.005, respectively). NEAT1 was positively correlated with SYVN1, and miR-125a-5p had a negative correlation with anti-cyclic citrullinated peptides. The ROC curve analysis showed the potential role of selected ncRNAs in RA pathogenesis.

CONCLUSION

The results indicate the ineffectiveness of the csDMARDs in reducing SYVN1 expression. The difference in expression of ncRNAs might be useful markers for monitoring disease activity and determining therapeutic responses in RA patients. Key Points • The expression of NEAT1 is significantly upregulated in RA patients compared to HC subjects. • miR-19b-3p, miR-125a-5p, and SYVN1 are significantly upregulated in RA patients compared to HC subjects. • The expression of miR-19b-3p and miR-125a-5p is significantly increased in RA patients after treatment with DMARDs and methylprednisolone. • NEAT1 is positively correlated with SYVN1.

Role of microRNAs and their downstream target transcription factors in zebrafish thrombopoiesis

Previous studies have shown that human platelets and megakaryocytes carry microRNAs suggesting their role in platelet function and megakaryocyte development, respectively. However, a comprehensive study on the microRNAs and their targets has not been undertaken. Zebrafish thrombocytes could be used as a model to study their role in megakaryocyte maturation and platelet function because thrombocytes have both megakaryocyte features and platelet properties. In our laboratory, we identified 15 microRNAs in thrombocytes using single-cell RNA sequencing. We knocked down each of these 15 microRNAs by the piggyback method and found knockdown of three microRNAs, mir-7148, let-7b, and mir-223 in adult zebrafish led to an increase in the percentage of thrombocytes. Functional thrombocyte analysis using plate tilt assay showed no modulatory effect of the three microRNAs on thrombocyte aggregation/agglutination. We also found enhanced thrombosis using arterial laser thrombosis assay in a group of zebrafish larvae after mir-7148, let-7b, and mir-223 knockdowns. These results suggested mir-7148, let-7b, and mir-223 are repressors for thrombocyte production. We then explored miRWalk database for let-7b downstream targets and then selected those that are expressed in thrombocytes, and from this list based on their role in differentiation selected 14 genes, rorca, tgif1, rfx1a, deaf1, zbtb18, mafba, cebpa, spi1a, spi1b, fhl3b, ikzf1, irf5, irf8, and lbx1b that encode transcriptional regulators. The qRT-PCR analysis of expression levels of the above genes following let-7b knockdown showed changes in the expression of 13 targets. We then studied the effect of the 13 targets on thrombocyte production and identified 5 genes, irf5, tgif1, irf8, cebpa, and rorca that showed thrombocytosis and one gene, ikzf1 that showed thrombocytopenia. Furthermore, we tested whether mir-223 regulates any of the above 13 transcription factors after mir-223 knockdown using qRT-PCR. Six of the 13 genes showed similar gene expression as observed with let-7b knockdown and 7 genes showed opposing results. Thus, our results suggested a possible regulatory network in common with both let-7b and mir-223. We also identified that tgif1, cebpa, ikzf1, irf5, irf8, and ikzf1 play a role in thrombopoiesis. Since the ikzf1 gene showed a differential expression profile in let-7b and mir-223 knockdowns but resulted in thrombocytopenia in ikzf1 knockdown in both adults and larvae we also studied an ikzf1 mutant and showed the mutant had thrombocytopenia. Taken together, these studies showed that thrombopoiesis is controlled by a network of transcription regulators that are regulated by multiple microRNAs in both positive and negative manner resulting in overall inhibition of thrombopoiesis.

Role of MicroRNAs and their Downstream Target Transcription Factors in Zebrafish Thrombopoiesis

Previous studies have shown that human platelets and megakaryocytes carry microRNAs suggesting their role in platelet function and megakaryocyte development, respectively. However, a comprehensive study on the microRNAs and their targets has not been undertaken. Zebrafish thrombocytes could be used as a model to study their role in megakaryocyte maturation and platelet function because thrombocytes have both megakaryocyte features and platelet properties. In our laboratory, we identified 15 microRNAs in thrombocytes using single-cell RNA sequencing. We knocked down each of these 15 microRNAs by the piggyback method and found knockdown of three microRNAs, mir-7148, let-7b , and mir-223 in adult zebrafish led to an increase in the percentage of thrombocytes. Functional thrombocyte analysis using plate tilt assay showed no modulatory effect of the three microRNAs on thrombocyte aggregation/agglutination. We also found enhanced thrombosis using arterial laser thrombosis assay in a group of zebrafish larvae after mir-7148, let-7b , and mir-223 knockdowns. These results suggested mir-7148, let-7b , and mir-223 are repressors for thrombocyte production. We then explored miRWalk database for let-7b downstream targets and then selected those that are expressed in thrombocytes, and from this list based on their role in differentiation selected 14 genes, rorca, tgif1, rfx1a, deaf1, zbtb18, mafba, cebpa, spi1a, spi1b, fhl3b, ikzf1, irf5, irf8 , and lbx1b that encode transcriptional regulators. The qRT-PCR analysis of expression levels of the above genes following let-7b knockdown showed changes in the expression of 13 targets. We then studied the effect of the 13 targets on thrombocyte production and identified 5 genes, irf5, tgif1, irf8, cebpa , and rorca that showed thrombocytosis and one gene, ikzf1 that showed thrombocytopenia. Furthermore, we tested whether mir-223 regulates any of the above 13 transcription factors after mir-223 knockdown using qRT-PCR. Six of the 13 genes showed similar gene expression as observed with let-7b knockdown and 7 genes showed opposing results. Thus, our results suggested a possible regulatory network in common with both let-7b and mir-223 . We also identified that tgif1, cebpa, ikzf1, irf5 , irf8 , and ikzf1 play a role in thrombopoiesis. Since the ikzf1 gene showed a differential expression profile in let-7b and mir-223 knockdowns but resulted in thrombocytopenia in ikzf1 knockdown in both adults and larvae we also studied an ikzf1 mutant and showed the mutant had thrombocytopenia. Taken together, these studies showed that thrombopoiesis is controlled by a network of transcription regulators that are regulated by multiple microRNAs in both positive and negative manner resulting in overall inhibition of thrombopoiesis.

Humulus lupus extract rich in xanthohumol improves the clinical course in critically ill COVID-19 patients

BACKGROUND

The systemic inflammatory response following severe COVID-19 is associated with poor outcomes. Several anti-inflammatory medications have been studied in COVID-19 patients. Xanthohumol (Xn), a natural extract from hop cones, possesses strong anti-inflammatory and antioxidative properties. The aim of this study was to analyze the effect of Xn on the inflammatory response and the clinical outcome of COVID-19 patients.

METHODS

Adult patients treated for acute respiratory failure (PaO₂/FiO₂ less than 150) were studied. Patients were randomized into two groups: Xn - patients receiving adjuvant treatment with Xn at a daily dose of 4.5 mg/kg body weight for 7 days, and C - controls. Observations were performed at four time points: immediately after admission to the ICU and on the 3rd, 5th, and 7th days of treatment. The inflammatory response was assessed based on the plasma IL-6 concentration, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), C-reactive protein (CRP) and D-dimer levels. The mortality rate was determined 28 days after admission to the ICU.

RESULTS

Seventy-two patients were eligible for the study, and 50 were included in the final analysis. The mortality rate was significantly lower and the clinical course was shorter in the Xn group than in the control group (20% vs. 48%, p < 0.05, and 9 ± 3 days vs. 22 ± 8 days, p < 0.001). Treatment with Xn decreased the plasma IL-6 concentration (p < 0.01), D-dimer levels (p < 0.05) and NLR (p < 0.01) more significantly than standard treatment alone.

CONCLUSION

Adjuvant therapy with Xn appears to be a promising anti-inflammatory treatment in COVID-19 patients.

Multiple functions and regulatory network of miR-150 in B lymphocyte-related diseases

MicroRNAs (miRNAs) play vital roles in the post-transcriptional regulation of gene expression. Previous studies have shown that miR-150 is a crucial regulator of B cell proliferation, differentiation, metabolism, and apoptosis. miR-150 regulates the immune homeostasis during the development of obesity and is aberrantly expressed in multiple B-cell-related malignant tumors. Additionally, the altered expression of MIR-150 is a diagnostic biomarker of various autoimmune diseases. Furthermore, exosome-derived miR-150 is considered as prognostic tool in B cell lymphoma, autoimmune diseases and immune-mediated disorders, suggesting miR-150 plays a vital role in disease onset and progression. In this review, we summarized the miR-150-dependent regulation of B cell function in B cell-related immune diseases.

Anti-inflammatory effect of miR-125a-5p on experimental optic neuritis by promoting the differentiation of Treg cells

Methylprednisolone pulse treatment is currently used for optic neuritis. It can speed visual recovery, but does not improve the ultimate visual outcomes. Recent studies have reported that miR-125a-5p has immunomodulatory effects on autoimmune diseases. However, it remains unclear whether miR-125a-5p has effects on optic neuritis. In this study, we used adeno-associated virus to overexpress or silence miR-125a-5p in mice. We found that silencing miR-125a-5p increased the latency of visual evoked potential and aggravated inflammation of the optic nerve. Overexpression of miR-125a-5p suppressed inflammation of the optic nerve, protected retinal ganglion cells, and increased the percentage of Treg cells. Our findings show that miR-125a-5p exhibits anti-inflammatory effects through promoting the differentiation of Treg cells.

Biomarkers (mRNAs and non-coding RNAs) for the diagnosis and prognosis of rheumatoid arthritis

In recent years, diagnostic and therapeutic approaches for rheumatoid arthritis (RA) have continued to improve. However, in the advanced stages of the disease, patients are unable to achieve long-term clinical remission and often suffer from systemic multi-organ damage and severe complications. Patients with RA usually have no overt clinical manifestations in the early stages, and by the time a definitive diagnosis is made, the disease is already at an advanced stage. RA is diagnosed clinically and with laboratory tests, including the blood markers C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) and the autoantibodies rheumatoid factor (RF) and anticitrullinated protein antibodies (ACPA). However, the presence of RF and ACPA autoantibodies is associated with aggravated disease, joint damage, and increased mortality, and these autoantibodies have low specificity and sensitivity. The etiology of RA is unknown, with the pathogenesis involving multiple factors and clinical heterogeneity. The early diagnosis, subtype classification, and prognosis of RA remain challenging, and studies to develop minimally invasive or non-invasive biomarkers in the form of biofluid biopsies are becoming more common. Non-coding RNA (ncRNA) molecules are composed of long non-coding RNAs, small nucleolar RNAs, microRNAs, and circular RNAs, which play an essential role in disease onset and progression and can be used in the early diagnosis and prognosis of RA. In this review of the diagnostic and prognostic approaches to RA disease, we provide an overview of the current knowledge on the subject, focusing on recent advances in mRNA-ncRNA as diagnostic and prognostic biomarkers from the biofluid to the tissue level.

Identification and characterization of non-coding RNA networks in infected macrophages revealing the pathogenesis of F. nucleatum-associated diseases

BACKGROUND

F. nucleatum, as an important periodontal pathogen, is not only closely associated with the development of periodontitis, but also implicated in systemic diseases. Macrophages may act as an important mediator in the pathogenic process of F. nucleatum infection. As non-coding RNAs (ncRNAs) have attracted extensive attention as important epigenetic regulatory mechanisms recently, we focus on the competing endogenous RNA (ceRNA) regulatory networks to elucidate the pathogenesis of F. nucleatum-associated diseases.

RESULTS

We screen abnormally expressed mRNAs, miRNAs, lncRNAs and circRNAs in macrophages after F. nucleatum infection via the whole transcriptome sequencing technology, including 375 mRNAs, 5 miRNAs, 64 lncRNAs, and 180 circRNAs. The accuracy of RNA-seq and microRNA-seq result was further verified by qRT-PCR analysis. GO and KEGG analysis show that the differentially expressed genes were mainly involved in MAPK pathway, Toll-like receptor pathway, NF-κB pathway and apoptosis. KEGG disease analysis reveals that they were closely involved in immune system diseases, cardiovascular disease, cancers, inflammatory bowel disease (IBD) et al. We constructed the underlying lncRNA/circRNA-miRNA-mRNA networks to understand their interaction based on the correlation analysis between the differentially expressed RNAs, and then screen the core non-coding RNAs. In which, AKT2 is controlled by hsa_circ_0078617, hsa_circ_0069227, hsa_circ_0084089, lncRNA NUP210, lncRNA ABCB9, lncRNA DIXDC1, lncRNA ATXN1 and lncRNA XLOC_237387 through miR-150-5p; hsa_circ_0001165, hsa_circ_0008460, hsa_circ_0001118, lncRNA XLOC_237387 and lncRNA ATXN1 were identified as the ceRNAs of hsa-miR-146a-3p and thereby indirectly modulating the expression of MITF.

CONCLUSIONS

Our data identified promising candidate ncRNAs responsible for regulating immune response in the F. nucleatum-associated diseases, offering new insights regarding the pathogenic mechanism of this pathogen.

Plasma miRNA Profile of Crohn's Disease and Rheumatoid Arthritis Patients

Crohn's disease (CD) and rheumatoid arthritis (RA) are immune mediated inflammatory diseases. Several studies indicate a role for microRNAs (miRNAs) in the pathogenesis of a variety of autoimmune diseases, including CD and RA. Our study's goal was to investigate circulating miRNAs in CD and RA patients to identify potential new biomarkers for early detection and personalized therapeutic approaches for autoimmune diseases. For this study, subjects with CD (n = 7), RA (n = 8) and healthy controls (n = 7) were recruited, and plasma was collected for miRNA sequencing. Comparison of the expression patterns of miRNAs between CD and healthy patients identified 99 differentially expressed miRNAs. Out of these miRNAs, 4 were down regulated, while 95 were up regulated. Comparison of miRNAs between RA and healthy patients identified 57 differentially expressed miRNAs. Out of those, 12 were down regulated, while 45 were up regulated. For all the miRNAs down regulated in CD and RA patients, 420 GO terms for biological processes were similarly regulated between both groups. Therefore, the identification of new plasma miRNAs allows the emergence of new biomarkers that can assist in the diagnosis and treatment of CD and RA.

Functional Interactions Between lncRNAs/circRNAs and miRNAs: Insights Into Rheumatoid Arthritis

Rheumatoid arthritis (RA) is one of the most common autoimmune diseases that affect synovitis, bone, cartilage, and joint. RA leads to bone and cartilage damage and extra-articular disorders. However, the pathogenesis of RA is still unclear, and the lack of effective early diagnosis and treatment causes severe disability, and ultimately, early death. Accumulating evidence revealed that the regulatory network that includes long non-coding RNAs (lncRNAs)/circular RNAs (circRNAs), micro RNAs (miRNAs), and messenger RNAs (mRNA) plays important roles in regulating the pathological and physiological processes in RA. lncRNAs/circRNAs act as the miRNA sponge and competitively bind to miRNA to regulate the expression mRNA in synovial tissue, FLS, and PBMC, participate in the regulation of proliferation, apoptosis, invasion, and inflammatory response. Thereby providing new strategies for its diagnosis and treatment. In this review, we comprehensively summarized the regulatory mechanisms of lncRNA/circRNA-miRNA-mRNA network and the potential roles of non-coding RNAs as biomarkers and therapeutic targets for the diagnosis and treatment of RA.

Circulating Mir-140 and leptin improve the accuracy of the differential diagnosis between psoriatic arthritis and rheumatoid arthritis: a case-control study

The differential diagnosis of psoriatic arthritis (PsA) and rheumatoid arthritis (RA) is difficult because of the lack of diagnostic clinical signs and reliable biomarkers. This study investigated microRNAs (miRNA) and adipokines as potential additional markers to discriminate PsA from RA. The expression profile of miRNA (miR-21, miR-140, miR-146a, miR-155, miR-181b, miR-223, miR-let-7e) and inflammatory cytokines (IL-1β, IL-6, IL-17a, IL-23a, TNF-α) from peripheral blood mononuclear cells of PsA and RA patients compared to healthy controls (HC) were evaluated by real-time PCR, and serum adipokines (adiponectin, chemerin, leptin, resistin, visfatin) and cytokines by ELISA assay. Univariable binary logistic regression was used to find the association between PsA and potential predictors. The gene expression of miRNA and cytokines and the serum levels of adipokines were found significantly different in PsA and RA patients compared to HC, as well as in PsA versus RA. MiR-140 gene expression resulted up-regulated in PsA patients and reduced in RA in comparison to HC, and, for the first time, significantly higher in PsA compared with RA. Serum levels of IL-23a and leptin were significantly increased in PsA and RA populations than in HC, as well as in PsA versus RA. Furthermore, circulating TNF-α was up-regulated in PsA and RA in comparison to controls, while resulted higher in RA than in PsA. Univariable binary logistic regression analysis found the above-mentioned markers associated to PsA versus RA. Our results first demonstrated an increased expression of circulating miR-140 and serum leptin in PsA patients compared to RA, which were identified as potential additional biomarkers to discriminate PsA from RA. Since the differential diagnosis of PsA and RA poses challenges in clinical practice, our data may help to enhance the diagnostic performance of PsA in daily practice.

Epigenetic Regulation (Including Micro-RNAs, DNA Methylation and Histone Modifications) of Rheumatoid Arthritis: A Systematic Review

The inflammatory reaction in rheumatoid arthritis (RA) is controlled by major epigenetic modifications that modulate the phenotype of synovial and immune cells. The aim of this work was to perform a systematic review focusing on miR expression, DNA methylation and histone modifications in RA. We demonstrated that, in human samples, the expressions of miR-155, miR-146a and miR-150 were significantly decreased while the expression of miR-410-3p was significantly increased in the RA group. Moreover, miR-146a significantly decreased pro-autoimmune IL-17 cytokine expression in RA. In a murine model, miR-34a inhibition can ameliorate the arthritis score. However, this evidence remain critically insufficient to support current therapeutic applications in RA patients.

The non-coding RNA interactome in joint health and disease

Non-coding RNAs have distinct regulatory roles in the pathogenesis of joint diseases including osteoarthritis (OA) and rheumatoid arthritis (RA). As the amount of high-throughput profiling studies and mechanistic investigations of microRNAs, long non-coding RNAs and circular RNAs in joint tissues and biofluids has increased, data have emerged that suggest complex interactions among non-coding RNAs that are often overlooked as critical regulators of gene expression. Identifying these non-coding RNAs and their interactions is useful for understanding both joint health and disease. Non-coding RNAs regulate signalling pathways and biological processes that are important for normal joint development but, when dysregulated, can contribute to disease. The specific expression profiles of non-coding RNAs in various disease states support their roles as promising candidate biomarkers, mediators of pathogenic mechanisms and potential therapeutic targets. This Review synthesizes literature published in the past 2 years on the role of non-coding RNAs in OA and RA with a focus on inflammation, cell death, cell proliferation and extracellular matrix dysregulation. Research to date makes it apparent that 'non-coding' does not mean 'non-essential' and that non-coding RNAs are important parts of a complex interactome that underlies OA and RA.

miR-223: An Effective Regulator of Immune Cell Differentiation and Inflammation

MicroRNAs (miRNAs) play a critical role in regulating various biological processes, such as cell differentiation and immune modulation by binding to their target genes. miR-223 is a miRNA with important functions and has been widely investigated in recent years. Under certain physiological conditions, miR-223 is regulated by different transcription factors, including sirtuin1 (Sirt1), PU.1 and Mef2c, and its biological functions are mediated through changes in its cellular or tissue expression. This review paper summarizes miR-223 biosynthesis and its regulatory role in the differentiation of granulocytes, dendritic cells (DCs) and lymphocytes, macrophage polarization, and endothelial and epithelial inflammation. In addition, it describes the molecular mechanisms of miR-223 in regulating lung inflammation, rheumatoid arthritis, enteritis, neuroinflammation and mastitis to provide insights into the existing molecular regulatory networks and therapies for inflammatory diseases in humans and animals.

miRNAs as potential biomarkers of treatment outcome in rheumatoid arthritis and ankylosing spondylitis

Common autoimmune, inflammatory rheumatic diseases including rheumatoid arthritis and ankylosing spondylitis can lead to structural and functional disability, an increase in mortality and a decrease in the quality of a patient's life. To date, the core of available therapy consists of nonsteroidal anti-inflammatory drugs, glucocorticoids and conventional synthetic disease-modifying antirheumatic drugs, like methotrexate. Nowadays, biological therapy including anti-TNF, IL-6 and IL-1 inhibitors, as well as antibodies targeting IL-17 and Janus kinase inhibitors have been found to be helpful in the management of rheumatic conditions. The review provides a summary of the current therapy strategies with a focus on miRNA, which is considered to be a potential biomarker and possible answer to the challenges in the prediction of treatment outcome in patients with rheumatoid arthritis and ankylosing spondylitis.

Biologic Drugs for Rheumatoid Arthritis in the Context of Biosimilars, Genetics, Epigenetics and COVID-19 Treatment

Rheumatoid arthritis (RA) affects around 1.2% of the adult population. RA is one of the main reasons for work disability and premature retirement, thus substantially increasing social and economic burden. Biological disease-modifying antirheumatic drugs (bDMARDs) were shown to be an effective therapy especially in those rheumatoid arthritis (RA) patients, who did not adequately respond to conventional synthetic DMARD therapy. However, despite the proven efficacy, the high cost of the therapy resulted in limitation of the widespread use and unequal access to the care. The introduction of biosimilars, which are much cheaper relative to original drugs, may facilitate the achievement of the therapy by a much broader spectrum of patients. In this review we present the properties of original biologic agents based on cytokine-targeted (blockers of TNF, IL-6, IL-1, GM-CSF) and cell-targeted therapies (aimed to inhibit T cells and B cells properties) as well as biosimilars used in rheumatology. We also analyze the latest update of bDMARDs' possible influence on DNA methylation, miRNA expression and histone modification in RA patients, what might be the important factors toward precise and personalized RA treatment. In addition, during the COVID-19 outbreak, we discuss the usage of biologicals in context of effective and safe COVID-19 treatment. Therefore, early diagnosing along with therapeutic intervention based on personalized drugs targeting disease-specific genes is still needed to relieve symptoms and to improve the quality of life of RA patients.

The complex functions of microRNA-150 in allergy, autoimmunity and immune tolerance

<abstract> <p>At present, special efforts are being made to develop the strategies allowing for activation of long-lasting antigen-specific immune tolerance in therapy of allergic and autoimmune diseases. Some of these therapeutic approaches are aimed at modulating cell functions at genetic level by using miRNA-based and miRNA-targeting treatments. Simultaneously, the crucial role of extracellular vesicles as natural miRNA conveyors is highlighted for induction of antigen-specific immune tolerance, especially that they appear to be easily manipulatable for therapeutic applications. Among other immune-related miRNAs, miR-150 is getting special attention as it is differently expressed by immune cells at various stages of their maturation and differentiation. In addition, miR-150 is involved in different signaling cascades orchestrating humoral and cell-mediated mechanisms of both innate and adaptive immune responses. Therefore, miR-150 is considered a master regulator of immunity in mammals. Currently, physiological miR-150-dependent regulatory circuits and causes of their malfunctioning that underlie the pathogenesis of allergic and autoimmune disorders are being unraveled. Thus, present review summarizes the current knowledge of the role of miR-150 in the pathogenesis and complications of these diseases. Furthermore, the involvement of miR-150 in regulation of immune responses to allergens and self-antigens and in induction of antigen-specific immune tolerance is discussed with the special emphasis on the therapeutic potential of this miRNA.</p> </abstract>

miR-146a-5p improves the decidual cytokine microenvironment by regulating the toll-like receptor signaling pathway in unexplained spontaneous abortion

Spontaneous abortion (SA) is a common pregnancy failure, but the cause of numerous cases remains unexplained. Decidual immune cells (DICs)-mediated cytokine microenvironment is involved in pregnancy and regulated by many microRNAs, but whether microRNA-146a-5p (miR-146a) regulate the decidual cytokine microenvironment and the potential mechanisms in unexplained SA pathogenesis have rarely been reported. In this study, the levels of cytokines and miR-146a in healthy and unexplained SA deciduae were first investigated, and the correlation between them was analyzed. Then, the effect of miR-146a inhibitor on cytokines was assessed in healthy deciduae-derived DICs. Third, the downstream targets and related molecular mechanisms of miR-146a were analyzed by bioinformatics, and the levels of the predicted targets in deciduae were assessed, followed by the correlation analysis between the levels of miR-146a and the targets. Finally, the effect of miR-146a on the predicted targets and inflammatory cytokines was validated in unexplained SA deciduae-derived DICs. As a result, decreased miR-146a correlated with the cytokine disorder in unexplained SA deciduae, and inhibition of miR-146a promoted pro-inflammatory response in healthy deciduae-derived DICs. One hundred four target genes and related molecular mechanisms of miR-146a were predicted, among which the toll-like receptor (TLR) pathway might be associated with the decidual cytokine regulation. Upregulation of miR-146a inhibited the expression of the predicted molecules enriched in the TLR pathway and improved the cytokine disorder in unexplained SA deciduae-derived DICs. Collectively, miR-146a improves the decidual cytokine microenvironment by regulating the TLR pathway in unexplained SA, providing novel potential targets for further therapeutic research.

Relationship between Sphk1/S1P and microRNAs in human cancers

Sphingosine kinases type 1 (SphK1) is a key enzyme in the phosphorylation of sphingosine to sphingosine 1-phosphate (S1P). Different abnormalities in SphK1 functions may correspond with poor prognosis in various cancers. Additionally, upregulated SphK1/S1P could promote cancer cell proliferation, angiogenesis, mobility, invasion, and metastasis. MicroRNAs as conserved small noncoding RNAs play major roles in cancer initiation, progression, metastasis, etc. Their posttranscriptionally mechanisms could affect the development of cancer growth or tumorigenesis suppression. The growing number of studies has described that various microRNAs can be regulated by SphK1, and its expression level can also be regulated by microRNAs. In this review, the relationship of SphK1 and microRNA functions and their interaction in human malignancies have been discussed. Based on them novel treatment strategies can be introduced.