title: A cell permeable peptide inhibitor of NFAT inhibits macrophage cytokine expression and ameliorates experimental colitis.
abstract: Nuclear factor of activated T cells (NFAT) plays a critical role in the development and function of immune and non-immune cells. Although NFAT is a central transcriptional regulator of T cell cytokines, its role in macrophage specific gene expression is less defined. Previous work from our group demonstrated that NFAT regulates Il12b gene expression in macrophages. Here, we further investigate NFAT function in murine macrophages and determined the effects of a cell permeable NFAT inhibitor peptide 11R-VIVIT on experimental colitis in mice. Treatment of bone marrow derived macrophages (BMDMs) with tacrolimus or 11R-VIVIT significantly inhibited LPS and LPS plus IFN-γ induced IL-12 p40 mRNA and protein expression. IL-12 p70 and IL-23 secretion were also decreased. NFAT nuclear translocation and binding to the IL-12 p40 promoter was reduced by NFAT inhibition. Experiments in BMDMs from IL-10 deficient (Il10(-/-)) mice demonstrate that inhibition of IL-12 expression by 11R-VIVIT was independent of IL-10 expression. To test its therapeutic potential, 11R-VIVIT was administered systemically to Il10(-/-) mice with piroxicam-induced colitis. 11R-VIVIT treated mice demonstrated significant improvement in colitis compared to mice treated with an inactive peptide. Moreover, decreased spontaneous secretion of IL-12 p40 and TNF in supernatants from colon explant cultures was demonstrated. In summary, NFAT, widely recognized for its role in T cell biology, also regulates important innate inflammatory pathways in macrophages. Selective blocking of NFAT via a cell permeable inhibitory peptide is a promising therapeutic strategy for the treatment of inflammatory bowel diseases.
authors.affiliation: Center for Gastrointestinal Biology and Diseases, Department of Medicine, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America.
authors.forename: Houda Z
authors.initials: HZ
authors.lastname: Elloumi
authors.forename: Nitsan
authors.initials: N
authors.lastname: Maharshak
authors.forename: Kavitha N
authors.initials: KN
authors.lastname: Rao
authors.forename: Taku
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Hyungjin S
authors.initials: HS
authors.lastname: Ryu
authors.forename: Marcus
authors.initials: M
authors.lastname: Mühlbauer
authors.forename: Fengling
authors.initials: F
authors.lastname: Li
authors.forename: Christian
authors.initials: C
authors.lastname: Jobin
authors.forename: Scott E
authors.initials: SE
authors.lastname: Plevy
mesh_terms: D021581:Active Transport, Cell Nucleus; D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology; D003092:Colitis / Q000378:metabolism* / Q000628:therapy; D016207:Cytokines / Q000096:biosynthesis*; D004195:Disease Models, Animal; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007249:Inflammation; D007371:Interferon-gamma / Q000378:metabolism; D016753:Interleukin-10 / Q000235:genetics; D053762:Interleukin-12 Subunit p40 / Q000378:metabolism; D008070:Lipopolysaccharides / Q000378:metabolism; D008264:Macrophages / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008856:Microscopy, Fluorescence / Q000379:methods; D050778:NFATC Transcription Factors / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000235:genetics; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D016559:Tacrolimus / Q000494:pharmacology
chemical_list: D016207:Cytokines; D053762:Interleukin-12 Subunit p40; D008070:Lipopolysaccharides; D050778:NFATC Transcription Factors; D012333:RNA, Messenger; D016753:Interleukin-10; D049452:Green Fluorescent Proteins; D007371:Interferon-gamma; D052247:Nitric Oxide Synthase Type II; D016559:Tacrolimus