title: Suppression of LPS-induced NF-κB activity in macrophages by the synthetic aurone, (Z)-2-((5-(hydroxymethyl) furan-2-yl) methylene) benzofuran-3(2H)-one.
abstract: Suppressing cytokine responses has frequently been shown to have promising therapeutic effects for many chronic inflammatory and autoimmune diseases. However, the severe side effects associated with the long-term use of current treatments, such as allergic reactions and increased risk of stroke, have focused attention towards the targeting of intracellular signaling mechanisms, such as NF-κB, that regulate inflammation. We synthesized a series of non-natural aurone derivatives and investigated their ability to suppress pro-inflammatory signaling in human monocyte (THP-1) and murine macrophage-like (RAW 267.4) cell lines. One of these derivatives, (Z)-2-((5-(hydroxymethyl) furan-2-yl) methylene) benzofuran-3(2H)-one (aurone 1), was found to inhibit LPS-induced secretion of the pro-inflammatory cytokines, tumor-necrosis factor α (TNFα), interleukin 1β (IL-1β), and IL-8 by THP-1 cells. To investigate the mechanism, we probed the effect of aurone 1 on LPS-induced MAPK and NF-κB signaling in both THP-1 and RAW264.7. While aurone 1 pre-treatment had no effect on the phosphorylation of ERK, JNK, or p38 MAPK, it strongly suppressed activation of IKK-β, as indicated by attenuation of Ser176/180 phosphorylation, resulting in decreased phosphorylation of p65 (ser536) as well as phosphorylation (ser32) and degradation of IκBα. Consistent with this, aurone 1 significantly reduced LPS-stimulated nuclear translocation of p65-containing NF-κB transcription factors and expression of an mCherry reporter of TNFα gene transactivation in RAW264.7 cells. Inhibition of TNFα expression at the transcription level was also demonstrated in THP-1 by qRT-PCR. In addition to its effects on cytokine expression, aurone 1 pre-treatment decreased expression of iNOS, a bona fide NF-κB target gene and marker of macrophage M1 polarization, resulting in decreased NO production in RAW264.7 cells. Together, these data indicate that aurone 1 may have the potential to function as a pharmacological agent for the treatment of chronic inflammation disorders.
authors.affiliation: Middle Tennessee State University, Department of Biology, 1301 East Main Street, Murfreesboro, TN 37132, USA. Electronic address: hsp2g@mtmail.mtsu.edu.
authors.forename: Hyo S
authors.initials: HS
authors.lastname: Park
authors.affiliation: Middle Tennessee State University, Department of Biology, 1301 East Main Street, Murfreesboro, TN 37132, USA. Electronic address: david.e.nelson@mtsu.edu.
authors.forename: David E
authors.initials: DE
authors.lastname: Nelson
authors.affiliation: Middle Tennessee State University, Department of Chemistry, 1301 East Main Street, Murfreesboro, TN 37132, USA. Electronic address: zet2d@mtmail.mtsu.edu.
authors.forename: Zachary E
authors.initials: ZE
authors.lastname: Taylor
authors.affiliation: Middle Tennessee State University, Department of Biology, 1301 East Main Street, Murfreesboro, TN 37132, USA. Electronic address: jhayes2582@gmail.com.
authors.forename: James B
authors.initials: JB
authors.lastname: Hayes
authors.affiliation: Middle Tennessee State University, Department of Chemistry, 1301 East Main Street, Murfreesboro, TN 37132, USA. Electronic address: kdc7c@mtmail.mtsu.edu.
authors.forename: Kirsten D
authors.initials: KD
authors.lastname: Cunningham
authors.affiliation: Middle Tennessee State University, Department of Biology, 1301 East Main Street, Murfreesboro, TN 37132, USA. Electronic address: baa2j@mtmail.mtsu.edu.
authors.forename: Brock A
authors.initials: BA
authors.lastname: Arivett
authors.affiliation: Middle Tennessee State University, Department of Biology, 1301 East Main Street, Murfreesboro, TN 37132, USA. Electronic address: rg3j@mtmail.mtsu.edu.
authors.forename: Rajarshi
authors.initials: R
authors.lastname: Ghosh
authors.affiliation: Middle Tennessee State University, Department of Biology, 1301 East Main Street, Murfreesboro, TN 37132, USA. Electronic address: lwolf4@uthsc.edu.
authors.forename: Larissa C
authors.initials: LC
authors.lastname: Wolf
authors.affiliation: Middle Tennessee State University, Department of Chemistry, 1301 East Main Street, Murfreesboro, TN 37132, USA. Electronic address: kmt4i@mtmail.mtsu.edu.
authors.forename: Kimberley M
authors.initials: KM
authors.lastname: Taylor
authors.affiliation: Middle Tennessee State University, Department of Biology, 1301 East Main Street, Murfreesboro, TN 37132, USA. Electronic address: mary.farone@mtsu.edu.
authors.forename: Mary B
authors.initials: MB
authors.lastname: Farone
authors.affiliation: Middle Tennessee State University, Department of Chemistry, 1301 East Main Street, Murfreesboro, TN 37132, USA. Electronic address: scott.handy@mtsu.edu.
authors.forename: Scott T
authors.initials: ST
authors.lastname: Handy
authors.affiliation: Middle Tennessee State University, Department of Biology, 1301 East Main Street, Murfreesboro, TN 37132, USA. Electronic address: Anthony.farone@mtsu.edu.
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Farone
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D001572:Benzofurans / Q000138:chemical synthesis / Q000494:pharmacology*; D016207:Cytokines / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000188:drug therapy*; D018836:Inflammation Mediators / Q000378:metabolism; D008070:Lipopolysaccharides / Q000276:immunology; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology; D051379:Mice; D009000:Monocytes / Q000187:drug effects* / Q000276:immunology; D016328:NF-kappa B / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D000067996:RAW 264.7 Cells; D015398:Signal Transduction / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism*
chemical_list: D000893:Anti-Inflammatory Agents; D001572:Benzofurans; D016207:Cytokines; D018836:Inflammation Mediators; D008070:Lipopolysaccharides; D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; C486837:aurone; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse
keywords: Anti-inflammatory; Aurone; IKK-β; Macrophage; NF-κB; iNOS