title: The Impact of MicroRNA-223-3p on IL-17 Receptor D Expression in Synovial Cells.
abstract: OBJECTIVE
  Rheumatoid arthritis (RA) is an autoimmune inflammatory disease affecting joints. Elevated plasma levels of microRNA-223-3p (miR-223-3p) in patients with RA are implicated in the pathogenesis of the disease. This study aimed to analyze the functional role of miR-223-3p in the pathogenesis of RA by overexpressing miR-223-3p in synovial cell lines.
  
  
  METHODS
  Arthritis was induced in the RA model of SKG mice by injection of ß-glucan. The histopathologic features of joints were examined using hematoxylin and eosin and immunohistochemical staining. Plasma levels of miRNA were determined by panel real-time PCR analysis. Target genes of the differentially expressed miRNAs in SKG mice were analyzed using miRNA target prediction algorithms. The dual-luciferase reporter system was used to evaluate the relationship between miR-223-3p and IL-17 receptor D (IL-17RD). The activity of miR-223-3p was analyzed by transfection of plasmid vectors overexpressing miR-223-3p into IL-17RD-expressing NIH3T3 and MH7A cell lines. Il6 and Il17rd mRNA expression was analyzed by quantitative real-time PCR. IL-17RD protein expression was analyzed by western blot analysis.
  
  
  RESULTS
  We identified 17 upregulated miRNAs (fold change > 2.0) in plasma of SKG mice injected with ß-glucan relative to untreated SKG mice. Il17rd was identified as the candidate target gene of miR-223-3p using five miRNA target prediction algorithms. The transfection of plasmid vectors overexpressing miR-223-3p into NIH3T3 and MH7A cells resulted in the downregulation of Il17rd expression and upregulation of Il6 expression. Expression of miR-223-3p and Il6 mRNA in MH7A cells was upregulated; however, that of Il17rd mRNA was downregulated following TNF-α stimulation. IL-17RD expression in synovial tissues from SKG mice and RA patients was inversely correlated with the severity of arthritis.
  
  
  CONCLUSIONS
  This study is the first to demonstrate that miR-223-3p downregulates IL-17RD in both mouse and human cells; miR-223-3p may contribute to the pathogenesis of RA by downregulating the expression of IL-17RD and upregulating that of IL-6 in synovial cells.
authors.affiliation: Department of Biopharmaceutics, School of Pharmacy, Hyogo University of Health Sciences, 1-3-6 Minatojima, Chuo-Ku, Kobe, Hyogo, Japan.
authors.forename: Nozomu
authors.initials: N
authors.lastname: Moriya
authors.affiliation: General Education Center, Hyogo University of Health Sciences, 1-3-6 Minatojima, Chuo-ku, Kobe, Hyogo, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Shibasaki
authors.affiliation: General Education Center, Hyogo University of Health Sciences, 1-3-6 Minatojima, Chuo-ku, Kobe, Hyogo, Japan.
authors.forename: Miki
authors.initials: M
authors.lastname: Karasaki
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1Mukogawa-cho, Nishinomiya, Hyogo, Japan.|Department of Pharmacotherapy, School of Pharmacy, Hyogo University of Health Sciences, 1-3-6 Minatojima, Chuo-ku, Kobe, Hyogo, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Iwasaki
mesh_terms: D000818:Animals; D001172:Arthritis, Rheumatoid / Q000378:metabolism; D015153:Blotting, Western; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism; D051379:Mice; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D041681:NIH 3T3 Cells; D060888:Real-Time Polymerase Chain Reaction; D053722:Receptors, Interleukin-17 / Q000235:genetics / Q000378:metabolism*; D013583:Synovial Membrane / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D047071:beta-Glucans / Q000494:pharmacology
chemical_list: D015850:Interleukin-6; C544877:MIRN223 microRNA, mouse; D035683:MicroRNAs; D053722:Receptors, Interleukin-17; D014409:Tumor Necrosis Factor-alpha; D047071:beta-Glucans