MicroRNA-138 regulates the balance of Th1/Th2 via targeting RUNX3 in psoriasis

Emerging insights into the role of natural products and miRNAs in psoriasis: from pathophysiology to precision medicine

Psoriasis is a sustainable skin disease characterized by inflammation resulting from the interaction between immune cells and keratinocytes. Significant advancements have been achieved in studying the molecular process behind noncoding and coding genes, leading to valuable insights for clinical therapy. Nevertheless, our comprehension of this intricate ailment remains ambiguous. Natural products such as curcumin, vitamin D, omega-3, vitamin E, psoralen, gallic acid (GA), and resveratrol offer a promising alternative or adjunct therapy for psoriasis by modulating multiple pathways and exhibiting fewer side effects compared to conventional treatments. MicroRNAs (miRNAs) are short RNAs that are involved in regulating gene expression after transcription, namely by suppressing gene activity. Recent research on miRNAs has uncovered their significant significance in the development of psoriasis. In this review, we examined the latest developments in the investigation of miRNAs in psoriasis. Previous studies have revealed that imbalanced miRNAs in psoriasis have a significant impact on the processes of keratinocyte differentiation, proliferation, and the progression of inflammation. Furthermore, miRNAs exert an impact on the activity of immune cells involved in psoriasis, such as Langerhans cells, dendritic cells, and CD4+ T cells. Furthermore, we explore potential miRNA-focused treatment options for psoriasis, including the localized administration of external miRNA mimics, and miRNA inhibitors. The effectiveness of natural products and miRNAs in treating psoriasis, as well as the signaling pathways that may be involved, are summarized in this article.

Psoriasis Treatments: Emerging Roles and Future Prospects of MicroRNAs

Psoriasis, a widespread and chronic inflammatory skin disorder, is marked by its persistence and the lack of a definitive cure. The pathogenesis of psoriasis is increasingly understood, with ongoing research highlighting the intricate interplay of genetic, immunological, and environmental factors. Recent advancements have illuminated the pivotal role of microRNAs in orchestrating complex processes in psoriasis and other hyperproliferative skin diseases. This narrative review highlights the emerging significance of miRNAs as key regulators in psoriasis pathogenesis and examines their potential as therapeutic targets. We discuss current treatment approaches and the promising future of miRNAs as next-generation therapeutic agents for this condition.

Circular RNAs as a novel class of potential therapeutic and diagnostic biomarkers in reproductive biology/diseases

Infertility is a prevalent problem among 10% of people within their reproductive years. Sometimes, even advanced treatment options like assisted reproduction technology have the potential to result in failed implantation. Because of the expected changes in gene expression during both in vitro and in vivo fertilization processes, these methods of assisting fertility have also been associated with undesirable pregnancy outcomes related to infertility. In this aspect, Circular RNAs (circRNAs) play a crucial role as epigenetic modifiers in a wide range of biological and pathological activities, including problems with fertility. CircRNAs are integral pieces in multiple cellular functions, including moving substances within the nucleus, silencing one X chromosome, cell death, the ability of stem cells to differentiate into different cell types, and the process of gene expression inherited from parental genes. Due to the progress made in high-speed gene sequencing, a large amount of circRNA molecules have been detected, revealing their significant functions in diverse biological functions like enhancing testicular development, preserving the differentiation and renewal of spermatogonial cells, and controlling spermatocyte meiosis. Moreover, these non-coding RNAs contribute in different aspects of female reproductive system including pregnancy-related diseases, gynecologic cancers, and endometriosis. In conclusion, there is no denying that circRNAs have immense potential to be used as biomarkers and treatments for reproductive disorders in males and females. In this research, we provide a comprehensive analysis of the multiple circRNAs associated with women's infertility.

RNA-Based Antipsoriatic Gene Therapy: An Updated Review Focusing on Evidence from Animal Models

Psoriasis presents as a complex genetic skin disorder, characterized by the interaction between infiltrated immune cells and keratinocytes. Substantial progress has been made in understanding the molecular mechanisms of both coding and non-coding genes, which has positively impacted clinical treatment approaches. Despite extensive research into the genetic aspects of psoriasis pathogenesis, fully grasping its epigenetic component remains a challenging endeavor. In response to the pressing demand for innovative treatments to alleviate inflammatory skin disorders, various novel strategies are under consideration. These include gene therapy employing antisense nucleotides, silencing RNA complexes, stem cell therapy, and antibody-based therapy. There is a pressing requirement for a psoriasis-like animal model that replicates human psoriasis to facilitate early preclinical evaluations of these novel treatments. The authors conduct a comprehensive review of various gene therapy in different psoriasis-like animal models utilized in psoriasis research. The animals included in the list underwent skin treatments such as imiquimod application, as well as genetic and biologic injections, and the results of these interventions are detailed. Animal models play a crucial role in translating drug discoveries from the laboratory to clinical practice, and these models aid in improving the reproducibility and clinical applicability of preclinical data. Numerous animal models with characteristics similar to those of human psoriasis have proven to be useful in understanding the development of psoriasis. In this review, the article focuses on RNA-based gene therapy exploration in different types of psoriasis-like animal models to improve the treatment of psoriasis.

Role of microRNAs in Immune Regulation with Translational and Clinical Applications

MicroRNAs (miRNAs) are 19-23 nucleotide long, evolutionarily conserved noncoding RNA molecules that regulate gene expression at the post-transcriptional level. In this review, involvement of miRNAs is summarized in the differentiation and function of immune cells, in anti-infective immune responses, immunodeficiencies and autoimmune diseases. Roles of miRNAs in anticancer immunity and in the transplantation of solid organs and hematopoietic stem cells are also discussed. Major focus is put on the translational clinical applications of miRNAs, including the establishment of noninvasive biomarkers for differential diagnosis and prediction of prognosis. Patient selection and response prediction to biological therapy is one of the most promising fields of application. Replacement or inhibition of miRNAs has enormous therapeutic potential, with constantly expanding possibilities. Although important challenges still await solutions, evaluation of miRNA fingerprints may contribute to an increasingly personalized management of immune dysregulation with a remarkable reduction in toxicity and treatment side effects. More detailed knowledge of the molecular effects of physical exercise and nutrition on the immune system may facilitate self-tailored lifestyle recommendations and advances in prevention.

Small nucleolar RNA Snora73 promotes psoriasis progression by sponging miR-3074-5p and regulating PBX1 expression

Chronic psoriasis is a kind of immune-mediated skin illness and the underlying molecular mechanisms of pathogenesis remain incompletely understood. Here, we used small RNA microarray assays to scan the differential expressed RNAs in psoriasis patient samples. The downstream miRNAs and its targets were predicted using bioinformatics analysis from online bases and confirmed using fluorescence in situ hybridization and dual‑luciferase report gene assay. Cell ability of proliferation and migration were detected using CCK-8 and transwell assays. The results showed that a new snoRNA Snora73 was upregulated in psoriasis patient samples. Overexpression of Snora73 significantly increased psoriasis cells viability and migration, while knockdown of Snora73 got the opposite results. Mechanistically, our results showed that Snora73 acted as a sponge for miR-3074-5p and PBX1 is a direct target of miR-3074-5p in psoriasis cells. Furthermore, miR-3074-5p suppressed psoriasis cell proliferation and migration, while PBX1 promoted cell proliferation and migration in psoriasis. Collectively, these findings reveal a crucial role of Snora73 in progression of psoriasis through miR-3074-5p/PBX1 signaling pathway and suggest a potential therapeutic strategy.

The extract from Portulaca oleracea L. rehabilitates skin photoaging via adjusting miR-138-5p/Sirt1-mediated inflammation and oxidative stress

Photoaging is the main form of external skin aging, and ultraviolet radiation is the main cause. Long-term ultraviolet radiation can cause oxidative stress, inflammation, immune responses, and skin cell apoptosis. Therefore, it is necessary to explore active products from plants to treat skin photoaging. C57BL/6J mice were randomly divided into control, model, and purslane (Portulaca oleracea L.) extract-treated groups (150, 300, and 600 mg/kg). Ultraviolet (UV) radiation induces skin photoaging. Histopathological changes in the skin were observed by hematoxylin and eosin (H&E), Masson's trichrome, and toluidine staining. Levels of hydroxyproline (HYP), hyaluronic acid (HA), collagen I (COL1), catalase (CAT), malondialdehyde (MDA), and total superoxide dismutase (T-SOD) were measured. UVB-induced BJ and HaCaT cells were used to evaluate the effects of the crude extract. The effects of the purslane extract on miR-138-5p/Sirt1 signaling were then tested. The results showed that the purslane extract significantly increased cell viability in UVB-induced cells and decreased oxidative damage and inflammation. In addition, the extract affected the miR-138-5p levels in vivo and in vitro, and increased the levels of the target gene Sirt1. In UVB-induced cells, purslane extract significantly altered the expression levels of genes or proteins associated with miR-138-5p/Sirt1 signaling. Inflammation and oxidative damage were significantly enhanced when miR-138-5p was overexpressed, and the expression levels of the genes and proteins were reversed by the extract. Co-transfection with the miR-138-5p inhibitor and si-Sirt1 showed the same effects as the extract on the signal. Similar results have been observed in mice. In summary, purslane extract showed potent protective effects against skin photoaging by regulating the miR-138-5p/Sirt1 axis and should be used as a natural product for skin care.

The role of microRNA in psoriasis: A review

Psoriasis is a chronic immune-mediated inflammatory skin disease that involves a complex interplay between infiltrated immune cells and keratinocytes. Great progress has been made in the research on the molecular mechanism of coding and non-coding genes, which has helped in clinical treatment. However, our understanding of this complex disease is far from clear. MicroRNAs (miRNAs) are small non-coding RNA molecules that are involved in post-transcriptional regulation, characterised by their role in mediating gene silencing. Recent studies on miRNAs have revealed their important role in the pathogenesis of psoriasis. We reviewed the current advances in the study of miRNAs in psoriasis; the existing research has found that dysregulated miRNAs in psoriasis notably affect keratinocyte proliferation and/or differentiation processes, as well as inflammation progress. In addition, miRNAs also influence the function of immune cells in psoriasis, including CD4+ T cells, dendritic cells, Langerhans cells and so on. In addition, we discuss possible miRNA-based therapy for psoriasis, such as the topical delivery of exogenous miRNAs, miRNA antagonists and miRNA mimics. Our review highlights the potential role of miRNAs in the pathogenesis of psoriasis, and we expect more research progress with miRNAs in the future, which will help us understand this complex skin disease more accurately.

Circ_0082476 targets miR-138-5p to promote proliferation, invasion, migration and inflammation in IL-22-treated human keratinocytes by upregulating BRD4

BACKGROUND

Circular RNAs (circRNAs) are implicated in the disease progression via acting as sponges of microRNAs (miRNAs) to regulate gene expression. The purpose of this study was to analyze the involvement of circ_0082476 in Interleukin-22 (IL-22)-induced psoriasis.

METHODS

Expression detection for circ_0082476, microRNA-424-5p (miR-138-5p) or toll-like receptor (BRD4) was completed using reverse transcription-quantitative polymerase chain reaction assay. Cell Counting Kit-8 assay and EdU assay were used for analysis of cell viability and proliferation, respectively. Cell invasion and migration abilities were assessed through transwell assay and wound healing assay. The protein expression was examined via western blot. Inflammatory reaction was determined via Enzyme-linked immunosorbent assay. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were conducted for target binding research.

RESULTS

Circ_0082476 was significantly elevated in psoriasis patients and IL-22-treated keratinocytes (HaCaT). Knockdown of circ_0082476 reduced cell proliferation, invasion and migration in IL-22-treated HaCaT cells. Circ_0082476 induced sponge effect on miR-138-5p. Circ_0082476 regulated IL-22-induced cell injury through targeting miR-138-5p. BRD4 was confirmed as a target of miR-138-5p, and miR-138-5p relieved IL-22-induced cell dysfunction by the direct downregulation of BRD4. BRD4 was positively regulated by circ_0082476 via sponging miR-138-5p.

CONCLUSION

These findings disclosed that circ_0082476 facilitated the IL22-induced epidermis cell injury in psoriasis through the upregulation of BRD4 via binding to miR-138-5p.

Triptolide Inhibits Th17 Response by Upregulating microRNA-204-5p and Suppressing STAT3 Phosphorylation in Psoriasis

Background

Psoriasis is an immune and inflammation-related skin disease. Triptolide with immunosuppressive and anti-inflammatory properties has been utilized for psoriasis treatment. However, the potential immunological mechanisms of triptolide have not been fully elucidated.

Methods

Using an imiquimod (IMQ)-induced psoriatic mouse model, we detected the effects of triptolide on psoriasis-like lesions including scales, thickening, and erythema. Methyl thiazol tetrazolium (MTT) cytotoxicity assay was performed for evaluating the influence of triptolide on cell viability. Gene expression at mRNA and protein levels were examined by reverse transcription-quantitative polymerase chain reaction and Western blot analysis, respectively. The combination between microRNA-204-5p (miR-204-5p) and signal transduction and transcription activator-3 (STAT3) was confirmed by luciferase reporter assay. Enzyme-linked immunosorbent assay was conducted to examine interleukin (IL)-17 and interferon-γ (IFN-γ) levels using corresponding kits. Hematoxylin and eosin staining was used for the visualization of epidermal thickness. Flow cytometry analysis was employed for examining T helper (Th) 17 cells.

Results

Triptolide ameliorated IMQ-induced psoriatic skin lesions manifested by the decreased psoriasis area and severity indexes (PASI) scores. Triptolide inhibited Th17 cell differentiation from splenocytes. Additionally, triptolide elevated miR-204-5p expression, whereas it downregulated STAT3 expression levels both in vitro and in vivo. Moreover, miR-204-5p directly targeted STAT3 in HaCaT cells. Furthermore, triptolide repressed the expression of proinflammatory cytokines in IMQ-evoked psoriasis-like mice.

Conclusion

Triptolide inhibits STAT3 phosphorylation via upregulating miR-204-5p and thus suppressing Th17 response in psoriasis.

Contribution of the Environment, Epigenetic Mechanisms and Non-Coding RNAs in Psoriasis

Despite the increasing research and clinical interest in the predisposition of psoriasis, a chronic inflammatory skin disease, the multitude of genetic and environmental factors involved in its pathogenesis remain unclear. This complexity is further exacerbated by the several cell types that are implicated in Psoriasis’s progression, including keratinocytes, melanocytes and various immune cell types. The observed interactions between the genetic substrate and the environment lead to epigenetic alterations that directly or indirectly affect gene expression. Changes in DNA methylation and histone modifications that alter DNA-binding site accessibility, as well as non-coding RNAs implicated in the post-transcriptional regulation, are mechanisms of gene transcriptional activity modification and therefore affect the pathways involved in the pathogenesis of Psoriasis. In this review, we summarize the research conducted on the environmental factors contributing to the disease onset, epigenetic modifications and non-coding RNAs exhibiting deregulation in Psoriasis, and we further categorize them based on the under-study cell types. We also assess the recent literature considering therapeutic applications targeting molecules that compromise the epigenome, as a way to suppress the inflammatory cutaneous cascade.

Subacute cadmium exposure modulates Th1 polarization to trigger ER stress-induced porcine hepatocyte apoptosis via regulation of miR-369-TNFα axis

Cadmium (Cd), as a common environmental pollutant, has been reported to cause T lymphocyte dysfunction and cell apoptosis in multiple organs. However, whether subacute Cd exposure can induce apoptosis of hepatocytes and the relationship with Th1/Th2 imbalance were still unclear. In this study, ten 6-week-old piglets were selected and randomly assigned into two groups, the control group and the Cd group. The control group was fed with the standard diet, and for the Cd group, the standard diet was supplemented with 20 mg/kg CdCl2; liver tissue was collected on the 40th day of the experiment. Immunofluorescence, qRT-PCR, and western blot were performed to detect the expression of miR-369, Th1/Th2 biomarkers, endoplasmic reticulum (ER) stress-related genes, and apoptotic genes. TUNEL assay was applied to stain apoptotic hepatocytes. In the Cd group, the apoptosis of hepatocytes was significantly increased, and associated with the declined expression of miR-369, Th1 polarization, the elevated expression of ER stress pathway genes and their downstream pro-apoptosis genes, and downregulated expression of anti-apoptotic genes. These results manifest that subacute Cd exposure mediates Th1 polarization to promote ER stress-induced porcine hepatocyte apoptosis via regulating miR-369-TNFα. These results not only provide a basis for the enrichment of Cd toxicology but also support a theoretical foundation for the prevention and therapy of Cd poisoning. Schematic diagram illustrating the proposed mechanism of subacute cadmium exposure modulates Th1 polarization to trigger ER stress-induced porcine hepatocyte apoptosis via regulation of miR-369-TNFα axis.

The Effect of miR-138 on the Function of Follicular Helper T Cells and the Differentiation of B Cells in Osteosarcoma

OBJECTIVE

To explore the effect of miR-138 on the function of follicular helper T (Tfh) cells and the differentiation of B cells in osteosarcoma.

METHODS

Clinically collect peripheral blood from osteosarcoma (OS) patients and healthy volunteers (HC), as well as OS tumor tissues (OS tumor) and adjacent tissues with normal histology (normal group). The CD4+CXCR5+Tfh cells of OS patients were screened and isolated by flow cytometry, and the expression of Tfh cell membrane surface antigens PD-1 and CTLA-4 was detected. In addition, qRT-PCR was used to detect the expression of miR-138 in tissues and Tfh cells, and the correlation relationship between miR-138 and PD-1 and CTLA-4 was analyzed. After interference or overexpression of miR-138 in Tfh cells, coculture with untreated B cells was done, and the levels of IL-10, IL-12, IL-21, and INF-γ in Tfh cell culture medium and the levels of IgM, IgG, and IgA in B cell culture medium after coculture were measured by ELISA. Flow cytometry was used to detect the expression of B cell membrane surface antigens CD27 and CD38 after coculture.

RESULTS

The rate of PD-1- and CTLA-4 positive cells in the peripheral blood and tissues of the OS group was significantly increased, the expression of miR-138 was significantly reduced, and the expression of miR-138 was negatively correlated with the expression of PD-1 and CTLA-4. In addition, upregulation of miR-138 can lead to a significant increase in the level of IL-10 in the supernatant of Tfh cells and a significant decrease in the levels of IL-12, IL-21, and INF-γ, which in turn leads to increased levels of IgM, IgG, and IgA released by B cells. At the same time, it significantly increases the rate of CD27- and CD38-positive cells and promotes the maturation of B cells. Downregulating miR-138 has the opposite effect.

CONCLUSION

Downregulating the expression of miR-138 in osteosarcoma can improve the dysfunction of CD4+CXCR5+Tfh cells and promote the differentiation of B cells.

Circ-IGF1R plays a significant role in psoriasis via regulation of a miR-194-5p/CDK1 axis

Psoriasis is a skin disorder that is classed as an autoimmune disease. It is characterized by excessive proliferation, abnormal migration and differentiation of keratinocytes, as well as inflammatory cell infiltration. Circular RNAs (circRNAs/circ) have been reported to play an important role in several aspects of psoriasis. Thus in the present study, the role of circ-insulin-like growth factor 1 receptor (circ-IGF1R) in the development of psoriasis was assessed, and the involvement of microRNA (miR)-194-5p was also investigated as its expression was downregulated in psoriasis. StarBase analysis and dual luciferase reporter assays confirmed the interaction between circ-IGF1R with miR-194-5p. The increased expression of circ-IGF1R and decreased expression of miR-194-5p were further confirmed by reverse transcription-quantitative polymerase chain reaction in interleukin (IL-22)-stimulated HaCaT cells. The increased proliferation, migration and invasion, as well as decreased apoptosis, caspase 3 activity and cleaved-caspase 3/caspase 3 ratio were observed in IL-22-stimulated HaCaT cells. Conversely, transfection of circ-IGF1R-small interfering (si)RNA resulted in significantly increased expression of miR-194-5p with or without stimulation of IL-22 in HaCaT cells, and also overcame the effects of the miR-194-5p inhibitor. Additionally, transfection of circ-IGF1R-siRNA inhibited cell proliferation, migration and invasion, which were reversed by transfection of a miR-194-5p inhibitor. Similarly, circ-IGF1R-siRNA promoted apoptosis, caspase 3 activity and the cleaved-caspase 3/caspase 3 ratio, which were reversed by miR-194-5p inhibitor. These results showed that circ-IGF1R could affect the proliferation, apoptosis, migration and invasion of IL-22-stimulated HaCaT cells by regulating the expression of miR-194-5p. Based on TargetScan prediction and dual luciferase reporter assays, it was shown that cyclin-dependent kinase (CDK)1 was targeted by miR-194-5p. Additionally, the expression of CDK1 was upregulated following stimulation with IL-22 in HaCaT cells at the mRNA and protein levels. Transfection of miR-194-5p mimic or miR-194-5p inhibitor negatively regulated CDK1 expression in the IL-22 induced HaCaT cells. In conclusion, circ-IGF1R-siRNA could inhibit the cell proliferation, migration and invasion, and induce apoptosis by regulating the miR-194-5p/CDK1 axis. circ-IGF1R may thus serve as a potential treatment target for psoriasis.

Construction of a lncRNA-miRNA-mRNA network to determine the key regulators of the Th1/Th2 imbalance in multiple sclerosis

Aim: The exact epigenetic mechanisms that determine the balance of T helper (Th)1 and Th2 cells and autoimmune responses in multiple sclerosis (MS) remain unclear. We aim to clarify these. Methods: A combination of bioinformatics analysis and molecular evaluations was utilized to identify master hub genes. Results: A competitive endogenous RNA network containing six long noncoding RNAs (lncRNAs), 21 miRNAs and 86 mRNAs was provided through enrichment analysis and a protein-protein interaction network. NEAT1 and MALAT1 were found as differentially expressed lncRNAs using Gene Expression Omnibus (GSE21942). Quantitative real-time PCR results demonstrate dysregulation in the RUNX3 (a regulator of Th1/Th2 balance), GATA3 and TBX21, as well as miR-544a and miR-210-3p (which directly target RUNX3). ELISA also confirmed an imbalance in IFN-γ (Th1)/IL-4 (Th2) in MS patients. Conclusion: Our findings introduce novel biomarkers leading to Th1/Th2 imbalance in MS.

Regulatory effects of miR-138 and RUNX3 on Th1/Th2 balance in peripheral blood of children with cough variant asthma

OBJECTIVES

To study the expression levels of microRNA-138 (miR-138) and Runt-related transcription factor 3 (RUNX3) in peripheral blood of children with cough variant asthma (CVA) and their regulatory effects on Th1/Th2 balance.

METHODS

Sixty-five children with CVA (CVA group) and 30 healthy children (control group) were enrolled. Peripheral venous blood samples were collected for both groups, and CD4⁺ T cells were isolated and cultured. Enzyme-linked immunosorbent assay was used to measure the levels of interferon (IFN)-γ, interleukin (IL)-2, IL-4, IL-5, and IL-13 that were secreted by CD4⁺ T cells. Flow cytometry was used to determine the percentages of Th1 and Th2 cells. Quantitative real-time PCR was used to measure the level of RUNX3 mRNA in CD4⁺ T cells and the level of miR-138 in peripheral blood. Western blot was used to determine the protein expression of RUNX3 in CD4⁺ T cells. The dual-luciferase reporter assay was used to determine the targeting effects of miR-138 and RUNX3. The RUNX3-mimic plasmid was transfected into CD4⁺ T cells, and the effects on the levels of IFN-γ, IL-2, IL-4, IL-5, and IL-13 and the percentages of Th1 and Th2 cells were measured.

RESULTS

Compared with the control group, the CVA group showed significantly decreased levels of IFN-γ and IL-2 from CD4⁺ T cells, significantly increased levels of IL-4, IL-5, and IL-13 from CD4⁺ T cells, significantly decreased Th1 cell percentage and Th1/Th2 ratio, and a significantly increased Th2 cell percentage (P<0.05). The CVA group showed significantly lower relative expression levels of RUNX3 mRNA and protein in CD4⁺ T cells in peripheral blood than the control group (P<0.001). The relative expression level of miR-138 was significantly higher in the CVA group than in the control group (P<0.001). MiR-138 could target the expression of RUNX3. Upregulating the expression of RUNX3 in CD4⁺ T cells induced significantly increased levels of IFN-γ and IL-2, significantly decreased levels of IL-4, IL-5, and IL-13, significantly increased Th1 cell percentage and Th1/Th2 ratio, and a significantly decreased Th2 cell percentage (P<0.05).

CONCLUSIONS

MiR-138 regulates Th1/Th2 balance by targeting RUNX3 in children with CVA, providing a new direction for the treatment of CVA.

Recent research progress on circular RNAs: Biogenesis, properties, functions, and therapeutic potential

Circular RNAs (circRNAs), an emerging family member of RNAs, have gained importance in research due to their new functional roles in cellular physiology and disease progression. circRNAs are usually available in a wide range of cells and have shown tissue-specific expression as well as developmental specific expression. circRNAs are characterized by structural stability, conservation, and high abundance in the cell. In this review, we discuss the different models of biogenesis. The properties of circRNAs such as localization, structure and conserved pattern, stability, and expression specificity are also been illustrated. Furthermore, we discuss the biological functions of circRNAs such as microRNA (miRNA) sponging, cell cycle regulation, cell-to-cell communication, transcription regulation, translational regulation, disease diagnosis, and therapeutic potential. Finally, we discuss the recent research progress and future perspective of circRNAs. This review provides an understanding of potential diagnostic markers and the therapeutic potential of circRNAs, which are emerging daily.

The Role of Epigenetic Factors in Psoriasis

Psoriasis is a chronic, systemic, immune-mediated disease with an incidence of approximately 2%. The pathogenesis of the disease is complex and not yet fully understood. Genetic factors play a significant role in the pathogenesis of the disease. In predisposed individuals, multiple trigger factors may contribute to disease onset and exacerbations of symptoms. Environmental factors (stress, infections, certain medications, nicotinism, alcohol, obesity) play a significant role in the pathogenesis of psoriasis. In addition, epigenetic mechanisms are considered result in modulation of individual gene expression and an increased likelihood of the disease. Studies highlight the significant role of epigenetic factors in the etiology and pathogenesis of psoriasis. Epigenetic mechanisms in psoriasis include DNA methylation, histone modifications and non-coding RNAs. Epigenetic mechanisms induce gene expression changes under the influence of chemical modifications of DNA and histones, which alter chromatin structure and activate transcription factors of selected genes, thus leading to translation of new mRNA without affecting the DNA sequence. Epigenetic factors can regulate gene expression at the transcriptional (via histone modification, DNA methylation) and posttranscriptional levels (via microRNAs and long non-coding RNAs). This study aims to present and discuss the different epigenetic mechanisms in psoriasis based on a review of the available literature.

LINC00870 regulates Th1/Th2 via the JAK/STAT pathway in peripheral blood mononuclear cells infected with Mycobacterium tuberculosis

Long, noncoding RNAs reportedly play vital roles in tuberculosis (TB). For example, upregulation of LINC00870 has been observed in tuberculosis, though its role and underlying mechanism remains unclear. In this study, we investigated the expression and effect of LINC00870 in Mycobacterium tuberculosis (MTB) infection by comparing MTB-infected peripheral blood mononuclear cells (PBMCs) with controls. The results showed LINC00870 was significantly increased in MTB infected PBMCs. Additionally, LINC00870 overexpression inhibited Th1-secreted cytokines while promoted Th2-secreted cytokine in MTB-infected PBMCs. Furthermore, LINC00870 promoted p-STAT5 and p-JAK2 protein expression, thus activating JAK/STAT signaling in MTB-infected PBMCs. Sputum and plasma samples were obtained from TB, latent tuberculosis infection (LTBI) patients and healthy controls. The qRT-PCR results showed higher levels of LINC00870 in the sputum and plasma from TB and LTBI patients compared to healthy controls. In addition, LINC00870 were decreased in both TB and LTBI patients after three month of therapy, respectively. The results showed a correlation between LINC00870 inhibition and Th1/Th2, as well as JAK/STAT signaling pathway in PBMCs from active TB patients. In conclusion, higher levels of LINC00870 in tuberculosis might be associated with Th1/Th2-related immune responses by activating JAK/STAT signaling. LINC00870 thus may be a novel biomarker for diagnosing and treating tuberculosis.

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.

miRNAs Flowing Up and Down: The Concerto of Psoriasis

Psoriasis is a chronic immune-mediated skin disease, whose hallmarks include keratinocyte hyperproliferation and CD4⁺ T cell subsets imbalance. Dysregulated microRNAs (miRNAs) identified in psoriasis have been shown to affect keratinocyte and T cell functions, with studies on the molecular mechanisms and intrinsic relationships of the miRNAs on the way. Here, we focus on the dysregulated miRNAs that contribute to the two hallmarks of psoriasis with the miRNA target genes confirmed. We review a network, in which, upregulated miR-31/miR-203/miR-155/miR-21 and downregulated miR-99a/miR-125b facilitate the excessive proliferation and abnormal differentiation of psoriatic keratinocytes; upregulated miR-210 and downregulated miR-138 work in concert to distort CD4⁺ T cell subsets balance in psoriasis. The miRNAs exert their functions through regulating key psoriasis-associated transcription factors including NF-κB and STAT3. Whether flowing up or down, these miRNAs collaborate to promote the development and maintenance of psoriasis.

Waiting in the wings: RUNX3 reveals hidden depths of immune regulation with potential implications for inflammatory bowel disease

BACKGROUND

Complex interactions between the environment and the mucosal immune system underlie inflammatory bowel disease (IBD). The involved cytokine signalling pathways are modulated by a number of transcription factors, one of which is runt-related transcription factor 3 (RUNX3).

OBJECTIVE

To systematically review the immune roles of RUNX3 in immune regulation, with a focus on the context of IBD.

METHODS

Relevant articles and reviews were identified through a Scopus search in April 2020. Information was categorized by immune cell types, analysed and synthesized. IBD transcriptome data sets and FANTOM5 regulatory networks were processed in order to complement the literature review.

RESULTS

The available evidence on the immune roles of RUNX3 allowed for its description in twelve cell types: intraepithelial lymphocyte, Th1, Th2, Th17, Treg, double-positive T, cytotoxic T, B, dendritic, innate lymphoid, natural killer and macrophages. In the gut, the activity of RUNX3 is multifaceted and context-dependent: it may promote homeostasis or exacerbated reactions via cytokine signalling and regulation of receptor expression. RUNX3 is mostly engaged in pathways involving ThPOK, T-bet, IFN-γ, TGF-β/IL-2Rβ, GATA/CBF-β, SMAD/p300 and a number of miRNAs. RUNX3 targets relevant to IBD may include RAG1, OSM and IL-17B. Moreover, in IBD RUNX3 expression correlates positively with GZMM, and negatively with IFNAR1, whereas in controls, it strongly associates with TGFBR3.

CONCLUSIONS

Dysregulation of RUNX3, mostly in the form of deficiency, likely contributes to IBD pathogenesis. More clinical research is needed to examine RUNX3 in IBD.

Insights into interplay of immunopathophysiological events and molecular mechanistic cascades in psoriasis and its associated comorbidities

Psoriasis is an inflammatory skin disease with complex pathogenesis and multiple etiological factors. Besides the essential role of autoreactive T cells and constellation of cytokines, the discovery of IL-23/Th17 axis as a central signaling pathway has unraveled the mechanism of accelerated inflammation in psoriasis. This has provided insights into psoriasis pathogenesis and revolutionized the development of effective biological therapies. Moreover, genome-wide association studies have identified several candidate genes and susceptibility loci associated with this disease. Although involvement of cellular innate and adaptive immune responses and dysregulation of immune cells have been implicated in psoriasis initiation and maintenance, there is still a lack of unifying mechanism for understanding the pathogenesis of this disease. Emerging evidence suggests that psoriasis is a high-mortality disease with additional burden of comorbidities, which adversely affects the treatment response and overall quality of life of patients. Furthermore, changing trends of psoriasis-associated comorbidities and shared patterns of genetic susceptibility, risk factors and pathophysiological mechanisms manifest psoriasis as a multifactorial systemic disease. This review highlights the recent progress in understanding the crucial role of different immune cells, proinflammatory cytokines and microRNAs in psoriasis pathogenesis. In addition, we comprehensively discuss the involvement of various complex signaling pathways and their interplay with immune cell markers to comprehend the underlying pathophysiological mechanism, which may lead to exploration of new therapeutic targets and development of novel treatment strategies to reduce the disastrous nature of psoriasis and associated comorbidities.

MicroRNAs in Several Cutaneous Autoimmune Diseases: Psoriasis, Cutaneous Lupus Erythematosus and Atopic Dermatitis

MicroRNAs (miRNAs) are endogenous small non-coding RNA molecules that regulate the gene expression at a post-transcriptional level and participate in maintaining the correct cell homeostasis and functioning. Different specific profiles have been identified in lesional skin from autoimmune cutaneous diseases, and their deregulation cause aberrant control of biological pathways, contributing to pathogenic conditions. Detailed knowledge of microRNA-affected pathways is of crucial importance for understating their role in skin autoimmune diseases. They may be promising therapeutic targets with novel clinical implications. They are not only present in skin tissue, but they have also been found in other biological fluids, such as serum, plasma and urine from patients, and therefore, they are potential biomarkers for the diagnosis, prognosis and response to treatment. In this review, we discuss the current understanding of the role of described miRNAs in several cutaneous autoimmune diseases: psoriasis (Ps, 33 miRNAs), cutaneous lupus erythematosus (CLE, 2 miRNAs) and atopic dermatitis (AD, 8 miRNAs). We highlight their role as crucial elements implicated in disease pathogenesis and their applicability as biomarkers and as a novel therapeutic approach in the management of skin inflammatory diseases.

MicroRNA-138-5p Suppresses Non-small Cell Lung Cancer Cells by Targeting PD-L1/PD-1 to Regulate Tumor Microenvironment

Non-small cell lung cancer (NSCLC) is still challenging for treatment owing to immune tolerance and evasion. MicroRNA-138 (miR-138) not only acts as a tumor suppressor to inhibit tumor cell proliferation and migration but also regulates immune response. The regulatory mechanism of miR-138 in NSCLC remains not very clear. Herein, we demonstrated that miR-138-5p treatment decreased the growth of tumor cells and increased the number of tumor-infiltrated DCs. miR-138-5p not only down-regulated the expression of cyclin D3 (CCND3), CCD20, Ki67, and MCM in A549/3LL cells, but also regulated the maturation of DCs in A549-bearing nude mice and the 3LL-bearing C57BL/6 mouse model, and DCs’ capability to enhance T cells to kill tumor cells. Furthermore, miR-138-5p was found to target PD-L1 to down-regulate PD-L1 on tumor cells to reduce the expression of Ki67 and MCM in tumor cells and decrease the tolerance effect on DCs. miR-138-5p also directly down-regulates the expression of PD-L1 and PD-1 on DCs and T cells. Similar results were obtained from isolated human non-small cell lung cancer (NSCLC) cells and DCs. Thus, miR-138-5p inhibits tumor growth and activates the immune system by down-regulating PD-1/PD-L1 and it is a promising therapeutic target for NSCLC.

The eminent roles of ncRNAs in the pathogenesis of psoriasis

Psoriasis is a chronic immune-related disorder in which both genetic and environmental parameters are involved. Recent studies have demonstrated dysregulation of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) in the peripheral blood or skin lesions of patients with psoriasis. While a number of lncRNAs such as MEG3, AL162231.4 and NONHSAT044111 have been down-regulated in the course of psoriasis, others including PRINS, MIR31HG, RP6‐65G23.1, MSX2P1, SLC6A14-1:1, NR_003062 have been up-regulated. Moreover, expressions of several miRNAs have been dysregulated in this disorder. Among dysregulated miRNAs are miR-126, miR-143, miR-19a and miR-155 whose diagnostic roles in the psoriasis have also been assessed. Dysregulated non-coding RNAs in this disorder participate in the regulation of chemokine signaling pathway and immune response, control of epidermal development and skin barrier as well as modulation of function of certain subsets of T cells. Besides, these transcripts possibly regulate activity of NF-κΒ, mTOR, MAPK and JAK-STAT signaling pathways. Besides, expression levels of circRNAs have been decreased in the psoriasis lesions. Massive alterations in the levels of lncRNAs and miRNAs in the psoriasis lesions or peripheral blood of affected individuals show participation of these transcripts in the pathogenesis of this disorder.

Deep Insights in Circular RNAs: from biogenesis to therapeutics

Abstract

Circular RNAs (circRNAs) have emerged as a universal novel class of eukaryotic non-coding RNA (ncRNA) molecules and are becoming a new research hotspot in RNA biology. They form a covalent loop without 5′ cap and 3′ tail, unlike their linear counterparts. Endogenous circRNAs in mammalian cells are abundantly conserved and discovered so far. In the biogenesis of circRNAs exonic, intronic, reverse complementary sequences or RNA-binding proteins (RBPs) play a very important role. Interestingly, the majority of them are highly conserved, stable, resistant to RNase R and show developmental-stage/tissue-specific expression. CircRNAs play multifunctional roles as microRNA (miRNA) sponges, regulators of transcription and post-transcription, parental gene expression and translation of proteins in various diseased conditions. Growing evidence shows that circRNAs play an important role in neurological disorders, atherosclerotic vascular disease, and cancer and potentially serve as diagnostic or predictive biomarkers due to its abundance in various biological samples. Here, we review the biogenesis, properties, functions, and impact of circRNAs on various diseases.

Graphical Abstract

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.

miRNAs as Therapeutic Targets in Inflammatory Disease

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

Construction of a lncRNA-miRNA-mRNA network to determine the regulatory roles of lncRNAs in psoriasis

Psoriasis is a chronic inflammatory skin disorder that impairs the quality of life of affected patients. Emerging studies indicate that certain long non-coding RNAs (lncRNAs) have important roles in psoriasis. However, the exact functions of lncRNAs and their regulatory mechanisms as competitive endogenous RNAs (ceRNAs) in psoriasis have remained to be fully elucidated. In the present study, differentially expressed lncRNAs, microRNAs (miRNAs) and mRNAs were identified by analyzing public datasets, and a psoriasis-associated lncRNA-miRNA-mRNA network was constructed based on the ceRNA theory. Furthermore, previously validated abnormally expressed miRNAs in psoriasis were identified by a systematic literature search in the PubMed and Web of Science databases, and a specific miRNA-associated lncRNA-miRNA-mRNA sub-network was extracted. Furthermore, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed using DAVID 6.8. A total of 253 lncRNAs, 106 miRNAs and 1,156 mRNAs were identified as being differentially expressed between psoriasis skin and healthy control skin. The present study identified two key lncRNAs that may potentially have a role in the pathogenesis of psoriasis: AL035425.3 and Prader Willi/Angelman region RNA 6. This integrative analysis enhances the understanding of the molecular mechanism of psoriasis and may provide novel therapeutic targets for the treatment of psoriasis.

MiR-223 regulates proliferation and apoptosis of IL-22-stimulated HaCat human keratinocyte cell lines via the PTEN/Akt pathway

Psoriasis, a chronic inflammatory skin disorder disease, is closely associated with hyperproliferation of keratinocytes. Upregulated miR-223 has been found in peripheral blood mononuclear cells from patients with psoriasis and from psoriatic skin. However, its role in keratinocytes remains unknown. We thus aimed to investigate the function of miR-223 in psoriasis. Interleukin-22 (IL-22) is a crucial keratinocyte trigger in the T-cell-mediated immune response to psoriasis. We found miR-223 to be overexpressed in psoriatic lesions and in IL-22-stimulated HaCaT cells. HaCaT cells then were transfected with a miR-223 mimic or inhibitor to overexpress or inhibit expression of miR-223, respectively. A Cell Counting Kit-8 assay revealed that miR-223 overexpression promoted and miR-223 downregulation inhibited proliferation in IL-22-stimulated HaCaT cells. Flow cytometry analysis certified that miR-223 overexpression decreased HaCaT cell apoptosis, whereas miR-223 downregulation increased it. A dual-luciferase reporter assay demonstrated that miR-223 directly targeted the phosphatase and tensin homolog (PTEN) gene. MiR-223 also negatively regulated mRNA and protein expression of PTEN and modulated the PTEN/Akt pathway in IL-22-stimulated HaCaT cells. PTEN silencing attenuated the activity of the miR-223 inhibitor in these cells via the PTEN/Akt pathway. Overall, the results showed that miR-223 increased proliferation and inhibited apoptosis of IL-22-stimulated keratinocytes via the PTEN/Akt pathway.

MicroRNA-466a-3p attenuates allergic nasal inflammation in mice by targeting GATA3

Allergic rhinitis is thought to be an allergic disease associated with immunoglobulin (Ig)E-mediated immune response, characterized by increased T helper type 2 (Th2) cytokine production, elevated eosinophil levels in the nasal mucosa and induced nasal secretions. MicroRNA (miRNA) microarray data revealed that the expression level of miR-466a-3p was significantly decreased. Notably, GATA binding protein (GATA-3) was identified as one of its target genes through miRNA target prediction web tools. The expression levels of miR-466a-3p were altered by mimics and lentivirus both in vivo and in vitro, similar to those of GATA-3. Furthermore, the symptoms and histology of allergic rhinitis as well as the levels of serum IgE and interleukin (IL)-4 were examined in different groups of mice. Interestingly, the results for lentiviral miR-466a-3p-treated allergic rhinitis mice were relatively similar to normal mice, compared to allergic rhinitis mice without treatment. Also, miR-466a-3p negatively regulated GATA-3 expression in allergic rhinitis mice, indicating the participant of Th2-cell responses in allergic rhinitis. Taken together, our findings highlight a new perspective on the role of miR-466a-3p in allergic rhinitis. In addition, this study provides a theoretical framework and experimental reference for future research targeting microRNAs as therapeutic targets and diagnostic biomarkers of allergic rhinitis.

Circular RNA and Alzheimer's Disease

Circular RNAs (circRNAs) represent a special group of noncoding single-stranded highly stable ribonucleic acid entities abundant in the eukaryotic transcriptome. These circular forms of RNAs are significantly enriched in human brain and retinal tissues. However, the biological evolution and function of these circRNAs are poorly understood. Recent reports showed circRNA to be an important player in the development of neurodegenerative diseases like Alzheimer's disease. With the progression of age, circRNA level increases in the brain and also in age-associated neurological disorder like Alzheimer's disease (AD), Parkinson's disease, inflammatory neuropathy, nervous system neoplasms, and prion diseases. One highly represented circRNA in the human brain and retina is a ciRS-7 (CDR1as) which acts as an endogenous, anticomplementary miRNA inhibitor or "sponge" to quench the normal functioning of miRNA-7. Low CDR1as level can lead to increase in miR-7 expression which downregulates the activity of ubiquitin protein ligase A (UBE2A), an important AD target, functionally involved in clearing toxic amyloid peptides from AD brain. This chapter focuses on the functional relationship of circRNA with AD and interplay of miRNA-mRNA-mediated genetic regulatory networks. Our conceptual understanding also suggests that circRNA can be considered as a potential biomarker and therapeutic target in AD diagnosis and treatment.

γδTDEs: An Efficient Delivery System for miR-138 with Anti-tumoral and Immunostimulatory Roles on Oral Squamous Cell Carcinoma

In this study, we sought to investigate the potential application of γδ T cell-derived extracellular vesicles (γδTDEs) as drug delivery system (DDS) for miR-138 in the treatment of oral squamous cell carcinoma (OSCC). Our data showed that overexpression of miR-138 in γδ T cells obtained miR-138-rich γδTDEs accompanying increased expansion and cytotoxicity of γδ T cells. γδTDEs inherited the cytotoxic profile of γδ T cells and could efficiently deliver miR-138 to OSCC cells, resulting in synergetic inhibition on OSCC both in vitro and in vivo. The pre-immunization by miR-138-rich γδTDEs inhibited the growth of OSCC tumors in immunocompetent C3H mice, but not in nude mice, suggesting an immunomodulatory role by miR-13-rich γδTDEs. γδTDEs and miR-138 additively increased the proliferation, interferon-γ (IFN-γ) production, and cytotoxicity of CD8⁺ T cells against OSCC cells. Only delivered by γδTDEs can miR-138 efficiently target programmed cell death 1 (PD-1) and CTLA-4 in CD8⁺ T cells. We conclude that γδTDEs delivering miR-138 could achieve synergetic therapeutic effects on OSCC, which is benefited from the individual direct anti-tumoral effects on OSCC and immunostimulatory effects on T cells by both γδTDEs and miR-138; γδTDEs could serve as an efficient DDS for microRNAs (miRNAs) in the treatment of cancer.

MicroRNAs in Autoimmunity and Hematological Malignancies

Autoimmunity and hematological malignancies are often concomitant in patients. A causal bidirectional relationship exists between them. Loss of immunological tolerance with inappropriate activation of the immune system, likely due to environmental and genetic factors, can represent a breeding ground for the appearance of cancer cells and, on the other hand, blood cancers are characterized by imbalanced immune cell subsets that could support the development of the autoimmune clone. Considerable effort has been made for understanding the proteins that have a relevant role in both processes; however, literature advances demonstrate that microRNAs (miRNAs) surface as the epigenetic regulators of those proteins and control networks linked to both autoimmunity and hematological malignancies. Here we review the most up-to-date findings regarding the miRNA-based molecular mechanisms that underpin autoimmunity and hematological malignancies.

Immune Regulation of Tissue Repair and Regeneration via miRNAs-New Therapeutic Target

The importance of immunity in tissue repair and regeneration is now evident. Thus, promoting tissue healing through immune modulation is a growing and promising field. Targeting microRNAs (miRNAs) is an appealing option since they regulate immunity through post-transcriptional gene fine-tuning in immune cells. Indeed, miRNAs are involved in inflammation as well as in its resolution by controlling immune cell phenotypes and functions. In this review, we first discuss the immunoregulatory role of miRNAs during the restoration of tissue homeostasis after injury, focusing mainly on neutrophils, macrophages and T lymphocytes. As tissue examples, we present the immunoregulatory function of miRNAs during the repair and regeneration of the heart, skeletal muscles, skin and liver. Secondly, we discuss recent technological advances for designing therapeutic strategies which target miRNAs. Specifically, we highlight the possible use of miRNAs and anti-miRNAs for promoting tissue regeneration via modulation of the immune system.

MicroRNA-210 overexpression promotes psoriasis-like inflammation by inducing Th1 and Th17 cell differentiation

Immune imbalance of T lymphocyte subsets is a hallmark of psoriasis, but the molecular mechanisms underlying this aspect of psoriasis pathology are poorly understood. Here, we report that microRNA-210 (miR-210), a miR that is highly expressed in both psoriasis patients and mouse models, induces helper T (Th) 17 and Th1 cell differentiation but inhibits Th2 differentiation through repressing STAT6 and LYN expression, contributing to several aspects of the immune imbalance in psoriasis. Both miR-210 ablation in mice and inhibition of miR-210 by intradermal injection of antagomir-210 blocked the immune imbalance and the development of psoriasis-like inflammation in an imiquimod-induced or IL-23-induced psoriasis-like mouse model. We further showed that TGF-β and IL-23 enhance miR-210 expression by inducing HIF-1α, which recruits P300 and promotes histone H3 acetylation in the miR-210 promoter region. Our results reveal a crucial role for miR-210 in the immune imbalance of T lymphocyte subsets in psoriasis and suggest a potential therapeutic avenue.

A catalog of potential putative functional variants in psoriasis genome-wide association regions

Psoriasis is a common inflammatory skin disease, with considerable genetic contribution. Genome-wide association studies have successfully identified a number of genomic regions for the risk of psoriasis. However, it is challenging to pinpoint the functional causal variants and then further decipher the genetic mechanisms underlying each region. In order to prioritize potential functional causal variants within psoriasis susceptibility regions, we integrated the genetic association findings and functional genomic data publicly available, i.e. histone modifications in relevant immune cells. We characterized a pervasive enrichment pattern of psoriasis variants in five core histone marks across immune cells/tissues. We discovered that genetic alleles within psoriasis association regions might influence gene expression levels through significantly affecting the binding affinities of 17 transcription factors. We established a catalog of 654 potential functional causal variants for psoriasis and suggested that they significantly overlapped with causal variants for autoimmune diseases. We identified potential causal variant rs79824801 overlay with the peaks of five histone marks in primary CD4+ T cells. Its alternative allele affected the binding affinity of transcription factor IKZF1. This study highlights the complex genetic architecture and complicated mechanisms for psoriasis. The findings will inform the functional experiment design for psoriasis.

Jinkui Shenqi Pills Ameliorate Asthma with "Kidney Yang Deficiency" by Enhancing the Function of the Hypothalamic-Pituitary-Adrenal Axis to Regulate T Helper 1/2 Imbalance

The aim of the study was to investigate the effects and underlying mechanism of JKSQP in a rat model of asthma with kidney-yang deficiency (KYD). Materials and Methods. Hydrocortisone (HYD) was used to establish the rat model of KYD; rats were then sensitized and challenged with ovalbumin (OVA). JKSQP was administered to OVA-challenged rats, and the changes in signs and symptoms of KYD were observed. The leukocyte number and subpopulations in bronchoalveolar lavage fluid (BALF) were counted and the cells were stained with Wright–Giemsa dye. Serum adrenocorticotropic hormone (ACTH), corticosterone (CORT), corticotropin-releasing hormone (CRH), total immunoglobulin E (IgE), and OVA-specific IgE levels were determined using relevant enzyme-linked immunosorbent assays (ELISA) kits. Results. JKSQP not only reversed the phenomenon of KYD but also significantly inhibited the number of leukocyte and eosinophils in the BALF, increasing the level of interferon (IFN)-γ and decreasing the levels of interleukin-4 (IL-4) and IgE in the serum compared with the OVA-challenged groups. Conclusions. Taken together, the antiasthma effects of JKSQP were likely mediated by the enhancement of the function of the hypothalamic-pituitary-adrenal axis and the reversal of T helper 1/2 imbalance.

Molecular Mechanisms and Management of a Cutaneous Inflammatory Disorder: Psoriasis

Psoriasis is a complex chronic inflammatory cutaneous disorder. To date, robust molecular mechanisms of psoriasis have been reported. Among diverse aberrant immunopathogenetic mechanisms, the current model emphasizes the role of Th1 and the IL-23/Th17 axis, skin-resident immune cells and major signal transduction pathways involved in psoriasis. The multiple genetic risk loci for psoriasis have been rapidly revealed with the advent of a novel technology. Moreover, identifying epigenetic modifications could bridge the gap between genetic and environmental risk factors in psoriasis. This review will provide a better understanding of the pathogenesis of psoriasis by unraveling the complicated interplay among immunological abnormalities, genetic risk foci, epigenetic modification and environmental factors of psoriasis. With advances in molecular biology, diverse new targets are under investigation to manage psoriasis. The recent advances in treatment modalities for psoriasis based on targeted molecules are also discussed.

MicroRNA-mediated regulation of immune responses to intestinal helminth infections

Intestinal helminth infections are highly prevalent in the developing world, often resulting in chronic infection and inflicting high host morbidity. With the emergence of drug-resistant parasites, a limited number of chemotherapeutic drugs available and stalling vaccine efforts, an increased understanding of antihelminth immunity is essential to provide new avenues to therapeutic intervention. MicroRNAs are a class of small, nonprotein coding RNAs which negatively regulate mRNA translation, thus providing finite control over gene expression in a plethora of biological settings. The miRNA-mediated coordinated control of gene expression has been shown to be essential in infection and immunity, in promoting and fine-tuning the appropriate immune response. This review gathers together and discusses observations of miRNA-mediated effects on the immune system and the subsequent impact on our understanding of antihelminth immunity.

Pathophysiology and Clinical Utility of Non-coding RNAs in Epilepsy

Epilepsy is a common neurologic disorder. The underlying pathological processes include synaptic strength, inflammation, ion channels, and apoptosis. Acting as epigenetic factors, non-coding RNAs (ncRNAs) participate in the regulation of pathophysiologic processes of epilepsy and are dysregulated during epileptogenesis. Aberrant expression of ncRNAs are observed in epilepsy patients and animal models of epilepsy. Furthermore, ncRNAs might also be used as biomarkers for diagnosis and the prognosis of treatment response in epilepsy. In this review, we will summarize the role of ncRNAs in the pathophysiology of epilepsy and the putative utilization of ncRNAs as diagnostic biomarkers and therapeutic targets.

Gene expression of miRNA-138 and cyclin D1 in oral lichen planus

OBJECTIVES

This study aimed to evaluate microRNA-138 (miR-138) gene expression and its target cyclin D1 (CCND1) gene and protein expression in oral lichen planus (OLP) mucosa in an attempt to investigate their possible roles in OLP immunopathogenesis.

METHODS

Sixty oral biopsy specimens were harvested from 30 healthy subjects and 30 OLP patients, subdivided into reticular, atrophic, and erosive groups (n = 10 each). Samples were subjected to quantitative real-time polymerase chain reaction analysis for quantification of miR-138 and CCND1 relative gene expression and immunohistochemical analysis to determine CCND1 protein expression.

RESULTS

Samples from OLP patients had a significant underexpression of miR-138 gene and overexpression of CCND1 at both gene and protein levels compared to normal mucosa samples. The lowest levels of miR-138 expression were observed in atrophic and erosive OLP compared to reticular OLP, and the highest levels of CCND1 gene and protein expression were in atrophic OLP. An inverse correlation was demonstrated between the miR-138 expression and both CCND1 gene and protein expression in OLP patients. A significant positive correlation between CCND1 gene and protein expression was also observed.

CONCLUSION

Downregulation of miR-138 increases the gene and protein expression of its potential target CCND1 in OLP mucosa which might have a pivotal role in the disease pathogenesis.

CLINICAL RELEVANCE

This research implied that miR-138 may have a role in identification of symptomatic OLP lesions. MiR-138 might be considered as a potential tool in future OLP molecular therapy.

MicroRNA-194 regulates keratinocyte proliferation and differentiation by targeting Grainyhead-like 2 in psoriasis

MicroRNAs (miRNAs) are currently emerged as important regulators in psoriasis. Psoriasis is characterized by hyperproliferation and impaired differentiation of keratinocytes in skin lesions. miR-194 is a well-known regulator of cell proliferation and differentiation. However, the role of miR-194 in psoriasis pathogenesis remains unclear. In this study we aimed to investigate the role of miR-194 in keratinocyte hyperproliferation and differentiation. We found that miR-194 was significantly downregulated in psoriasis lesional skin. Overexpression of miR-194 inhibited the proliferation and promoted the differentiation of primary human keratinocytes, whereas miR-194 suppression promoted the proliferation and inhibited their differentiation. Bioinformatic analysis predicted that the Grainyhead-like 2 (GRHL2) was a target gene of miR-194, which we further validated with a dual-luciferase reporter assay, real-time quantitative polymerase chain reaction (RT-qPCR), and Western blot analysis. The effect of miR-194 on cell proliferation and differentiation was significantly reversed by overexpression of GRHL2. Moreover, the expression of miR-194 and GRHL2 was inversely correlated in psoriasis lesional skin. Taken together, our results suggest that miR-194 inhibits the proliferation and promotes the differentiation of keratinocytes through targeting GRHL2. The downregulation of miR-194 expression may contribute to the pathogenesis of psoriasis and targeting miR-194 may represent a novel and potential therapeutic strategy for psoriasis.

Circular RNA: a new star in neurological diseases

Circular RNAs (circRNAs) are novel endogenous non-coding RNAs characterized by the presence of a covalent bond linking the 3' and 5' ends generated by backsplicing. In this review, we summarize a number of the latest theories regarding the biogenesis, properties and functions of circRNAs. Specifically, we focus on the advancing characteristics and functions of circRNAs in the brain and neurological diseases. CircRNAs exhibit the characteristics of species conservation, abundance and tissue/developmental-stage-specific expression in the brain. We also describe the relationship between circRNAs and several neurological diseases and highlight their functions in neurological diseases.

microRNAs in Psoriasis

Psoriasis is a chronic inflammatory skin condition resulting from a complex interplay among the immune system, keratinocytes, susceptibility genes, and environmental factors. However, the pathogenesis of psoriasis is not completely elucidated. microRNAs represent a promising class of small, noncoding RNA molecules that function to regulate gene expression. Although microRNA research in psoriasis and dermatology is still relatively new, evidence is rapidly accumulating for the role of microRNAs in the pathogenesis of psoriasis and other chronic inflammatory conditions. In this article, we present a comprehensive review of what is known about microRNAs and their role in the pathogenesis of psoriasis.

Roles of Circular RNAs in Neurologic Disease

Circular RNAs (circRNAs) are a novel type of endogenous noncoding RNA receiving increasing attention. They have been shown to act as a natural microRNA sponges that repress the activity of corresponding miRNAs by binding with them, thus regulating target genes. Numerous studies have shown that miRNAs are involved in the pathogenesis of neurological diseases. Therefore, circRNAs may act as important regulatory factors in the occurrence and development processes of neurological disease.