The Liver X Receptor Is Upregulated in Monocyte-Derived Macrophages and Modulates Inflammatory Cytokines Based on LXR α Polymorphism

Mediators Inflamm. 2019 Feb 28:2019:6217548. doi: 10.1155/2019/6217548. eCollection 2019.

Abstract

Liver X receptors (LXRs) have emerged as important regulators of inflammatory gene expression. Previously, we had reported that an LXRα gene promoter polymorphism (-1830 T > C) is associated with systemic lupus erythematosus (SLE). Therefore, we assessed cytokine expression in relation to LXRα polymorphism in monocyte-derived macrophages from patients with SLE. Macrophages were obtained after 72 hours of culture of human monocytes supplemented with phorbol 12-myristate 13-acetate. Cells were transfected with LXRα promoter constructs. Additionally, peripheral blood mononuclear cell- (PBMC-) derived macrophages from the patients were evaluated for proinflammatory cytokines in relation to the genotypes of LXRα -1830 T > C. The expression of LXRα was increased in macrophages; levels of proinflammatory cytokines were decreased with LXRα expression. Production of proinflammatory cytokines varied depending on LXRα -1830 T > C genotype. In particular, expression of LXRα was decreased and that of proinflammatory cytokines was increased for LXRα -1830 TC genotype compared to that for TT genotype. The data were consistent in PBMC-derived macrophages from patients with SLE. Increased proinflammatory cytokines is related to TLR7 and TLR9 expression. These data suggest that the expression levels of LXRα, according to LXRα -1830 T > C genotype, may contribute to the inflammatory response by induction of inflammatory cytokines in SLE.

MeSH terms

  • Benzoates / pharmacology
  • Benzylamines / pharmacology
  • Cell Differentiation / drug effects
  • Cell Differentiation / genetics
  • Cell Line, Tumor
  • Cytokines / metabolism
  • Genotype
  • Humans
  • Hydrocarbons, Fluorinated / pharmacology
  • Immunoblotting
  • Leukocytes, Mononuclear / drug effects
  • Leukocytes, Mononuclear / metabolism*
  • Liver X Receptors / agonists
  • Liver X Receptors / genetics*
  • Liver X Receptors / metabolism*
  • Macrophages / drug effects
  • Macrophages / metabolism*
  • Real-Time Polymerase Chain Reaction
  • Sulfonamides / pharmacology
  • Toll-Like Receptor 7 / genetics
  • Toll-Like Receptor 7 / metabolism
  • Toll-Like Receptor 9 / genetics
  • Toll-Like Receptor 9 / metabolism

Substances

  • Benzoates
  • Benzylamines
  • Cytokines
  • GW 3965
  • Hydrocarbons, Fluorinated
  • Liver X Receptors
  • NR1H3 protein, human
  • Sulfonamides
  • T0901317
  • TLR7 protein, human
  • TLR9 protein, human
  • Toll-Like Receptor 7
  • Toll-Like Receptor 9