title: Corn Silk Extract and Its Bioactive Peptide Ameliorated Lipopolysaccharide-Induced Inflammation in Mice via the Nuclear Factor-κB Signaling Pathway.
abstract: Bioactive peptides derived from foods have shown beneficial anti-inflammatory potential. Inhibitory κB kinase-β (IKKβ) plays a crucial role in the activation of nuclear factor-κB (NF-κB), a transcription factor involved in inflammation. Here we applied proteomic and bioinformatics approaches to identify anti-inflammatory peptides that target IKKβ from corn silk. Corn silk extract significantly suppressed lipopolysaccharide (LPS)-induced NF-κB activities [(1.7 ± 0.2)-fold vs (3.0 ± 0.6)-fold, p < 0.05] in cells. Trypsin hydrolysate of corn silk also suppressed LPS-induced NF-κB activities [(1.1 ± 0.3)-fold vs 3.3 ± 0.5 fold, p < 0.01]. In addition, both corn silk extract and trypsin hydrolysate significantly inhibited LPS-induced interleukin-1β (IL-1β) production by 58.3 ± 4.5 and 55.1 ± 7.4%, respectively. A novel peptide, FK2, docked into the ATP-binding pocket of IKKβ, was further identified from trypsin hydrolysis of corn silk. FK2 inhibited IKKβ activities, IκB phosphorylation, and subsequent NF-κB activation [(2.3 ± 0.4)-fold vs (5.5 ± 0.4)-fold, p < 0.001]. Moreover, FK2 significantly reduced NF-κB-driven luminescent signals in organs by 5-11-fold and suppressed LPS-induced NF-κB activities and IL-β production in tissues. In conclusion, our findings indicated that corn silk displayed anti-inflammatory abilities. In addition, we first identified an anti-inflammatory peptide FK2 from corn silk. Moreover, the anti-inflammatory effect of FK2 might be through IKKβ-NF-κB signaling pathways.
authors.affiliation: Graduate Institute of Chinese Medicine, China Medical University , Taichung, Taiwan.|Department of Health and Nutrition Biotechnology, Asia University , Taichung, Taiwan.
authors.forename: Tin-Yun
authors.initials: TY
authors.lastname: Ho
authors.affiliation: Graduate Institute of Chinese Medicine, China Medical University , Taichung, Taiwan.
authors.forename: Chia-Cheng
authors.initials: CC
authors.lastname: Li
authors.affiliation: Graduate Institute of Chinese Medicine, China Medical University , Taichung, Taiwan.
authors.forename: Hsin-Yi
authors.initials: HY
authors.lastname: Lo
authors.affiliation: Graduate Institute of Chinese Medicine, China Medical University , Taichung, Taiwan.
authors.forename: Feng-Yuan
authors.initials: FY
authors.lastname: Chen
authors.affiliation: Department of Microbiology, China Medical University , Taichung, Taiwan.
authors.forename: Chien-Yun
authors.identifier: http://orcid.org/0000-0002-6507-8015
authors.initials: CY
authors.lastname: Hsiang
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage* / Q000737:chemistry / Q000302:isolation & purification; D005260:Female; D051550:I-kappa B Kinase / Q000235:genetics / Q000276:immunology; D007249:Inflammation / Q000188:drug therapy* / Q000235:genetics / Q000276:immunology; D008070:Lipopolysaccharides / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D016328:NF-kappa B / Q000235:genetics / Q000276:immunology*; D010455:Peptides / Q000008:administration & dosage* / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification; D010940:Plant Proteins / Q000008:administration & dosage / Q000737:chemistry* / Q000276:immunology; D040901:Proteomics; D015398:Signal Transduction / Q000187:drug effects; D003313:Zea mays / Q000737:chemistry*
chemical_list: D000893:Anti-Inflammatory Agents; D008070:Lipopolysaccharides; D016328:NF-kappa B; D010455:Peptides; D010940:Plant Proteins; D051550:I-kappa B Kinase
keywords: corn silk; inflammation; inhibitory κB kinase-β; nuclear factor-κB; peptide