title: 6-Methoxyflavone inhibits NFAT translocation into the nucleus and suppresses T cell activation.
abstract: NFAT plays a crucial role in the immune system by regulating the transcription of inducible genes during immune responses. In T cells, NFAT proteins govern various cellular events related to T cell development, activation, tolerance induction, and differentiation. We previously reported the NFAT1-dependent enhancer activity of conserved noncoding sequence (CNS)-9, a distal cis-acting element, in the regulation of IL-10 transcription in T cells. In this study, we developed a T cell-based reporter system to identify compounds that modulate the regulatory activity of CNS-9. Among the identified candidates, 6-methoxyflavone (6-MF) significantly inhibited the enhancer activity of CNS-9, thereby reducing IL-10 expression in T cells without affecting cell viability. 6-MF also downregulated the transcription of NFAT1 target genes such as IL-4, IL-13, and IFN-γ. Treatment of 6-MF inhibited the translocation of NFAT1 into the nucleus, which consequently interrupted NFAT1 binding to the target loci, without affecting the expression or dephosphorylation of NFAT1. Treatment of 6-MF to CD4(+) T cells or B cells isolated from mice with atopic dermatitis significantly reduced disease-associated cytokine production, as well as the levels of IgE. In addition, oral administration of 6-MF to atopic dermatitis mice ameliorated disease symptoms by reducing serum IgE levels and infiltrating lymphocytes. Conclusively, our results suggest that 6-MF can be a potential candidate for the development of an effective immunomodulator via the suppression of NFAT-mediated T cell activation.
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea; Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY 10021;
authors.forename: Jae-Seon
authors.initials: JS
authors.lastname: So
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea; Academy of Immunology and Microbiology, Institute for Basic Science, Pohang 790-784, Republic of Korea;
authors.forename: Gi-Cheon
authors.initials: GC
authors.lastname: Kim
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea; Graduate Program in Immunology and Microbial Pathogenesis, Weill Cornell Medical College, New York, NY 10021;
authors.forename: Minkyung
authors.initials: M
authors.lastname: Song
authors.affiliation: Academy of Immunology and Microbiology, Institute for Basic Science, Pohang 790-784, Republic of Korea;
authors.forename: Choong-Gu
authors.initials: CG
authors.lastname: Lee
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea; Academy of Immunology and Microbiology, Institute for Basic Science, Pohang 790-784, Republic of Korea;
authors.forename: Eunbee
authors.initials: E
authors.lastname: Park
authors.affiliation: National Cancer Center, Korea, Goyang 410-769, Republic of Korea;
authors.forename: Ho Jin
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Division of Drug Discovery Research, Korea Research Institute of Chemical Technology, Daejeon 305-600, Republic of Korea; and.
authors.forename: Young Sup
authors.initials: YS
authors.lastname: Kim
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea;
authors.forename: Chang-Duk
authors.initials: CD
authors.lastname: Jun
authors.affiliation: Academy of Immunology and Microbiology, Institute for Basic Science, Pohang 790-784, Republic of Korea; Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea iimsh@postech.ac.kr.
authors.forename: Sin-Hyeog
authors.initials: SH
authors.lastname: Im
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000276:immunology*; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D045744:Cell Line, Tumor; D002467:Cell Nucleus; D017124:Conserved Sequence / Q000187:drug effects / Q000235:genetics; D016207:Cytokines / Q000096:biosynthesis; D004268:DNA-Binding Proteins / Q000235:genetics; D003876:Dermatitis, Atopic / Q000188:drug therapy / Q000276:immunology; D047309:Flavones / Q000494:pharmacology*; D057809:HEK293 Cells; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D007371:Interferon-gamma / Q000096:biosynthesis / Q000235:genetics; D016753:Interleukin-10 / Q000096:biosynthesis / Q000235:genetics; D018793:Interleukin-13 / Q000096:biosynthesis / Q000235:genetics; D015847:Interleukin-4 / Q000096:biosynthesis / Q000235:genetics; D008213:Lymphocyte Activation / Q000187:drug effects*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D050778:NFATC Transcription Factors / Q000037:antagonists & inhibitors / Q000276:immunology*; D010766:Phosphorylation; D011485:Protein Binding / Q000187:drug effects; D022661:RNA, Untranslated / Q000187:drug effects / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: C000593132:6-methoxyflavone; D016207:Cytokines; D004268:DNA-Binding Proteins; D047309:Flavones; C556062:IL10 protein, mouse; D018793:Interleukin-13; D050778:NFATC Transcription Factors; C494007:Nfatc2 protein, mouse; D022661:RNA, Untranslated; D016753:Interleukin-10; D015847:Interleukin-4; D007073:Immunoglobulin E; D007371:Interferon-gamma