title: Eupafolin ameliorates COX-2 expression and PGE2 production in particulate pollutants-exposed human keratinocytes through ROS/MAPKs pathways.
abstract: BACKGROUND
  Eupafolin is a major bioactive compound derived from the methanolic extract of the medicinal herb Phyla nodiflora, which has been used in traditional Chinese medicine to treat various inflammatory diseases. Recently, particulate air pollutants have been shown to induce inflammation of the skin. In this study, we seek to determine whether eupafolin can inhibit the production of inflammatory mediators in a human skin keratinocyte cell line exposed to particulate air pollutants (particulate matter, PM), and determine the molecular mechanisms involved.
  
  
  METHODS
  Human keratinocyte HaCaT cells were treated with PM in the presence or absence of eupafolin. Cyclooxygenase-2 (COX-2) protein and gene expression levels were determined by Western blotting, RT-PCR and luciferase activity assay. Prostaglandin E2 (PGE2) production was evaluated by the enzyme immunoassay method. Generation of intracellular reactive oxygen species (ROS) was measured by the dichlorofluorescin (DCFH) oxidation assay, and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity was determined by a chemiluminescence assay. For in vivo studies, COX-2 expression in the skin of BALB/c nude mice was analyzed by immunohistochemistry.
  
  
  RESULTS
  Eupafolin inhibited PM-induced COX-2 protein and gene expression and PGE2 production in HaCaT cells. In addition, eupafolin suppressed PM-induced intracellular ROS generation, NADPH oxidase activity, MAPK (ERK, JNK and p38) activation and NK-κB activation. In vivo studies showed that topical treatment with eupafolin inhibited COX-2 expression in the epidermal keratinocytes of PM-treated mice.
  
  
  CONCLUSIONS
  Eupafolin exerts anti-inflammatory and antioxidant effects on skin keratinocytes exposed to particulate air pollutants, and may have potential use in the treatment or prevention of air pollutant-induced inflammatory skin diseases in the future.
authors.affiliation: Division of Basic Medical Sciences, Department of Nursing, Chang Gung Institute of Technology and Chronic Diseases and Health Promotion Research Center, Chiayi, Taiwan; Research Center for Industry of Human Ecology, Chang Gung University of Science and Technology, Kweishan, Taoyuan Taiwan.
authors.forename: Chiang-Wen
authors.initials: CW
authors.lastname: Lee
authors.affiliation: Graduate Institute of BioMedical Sciences, Chang Gung University, Kweishan, Taoyuan, Taiwan; Pharmaceutics Laboratory, Graduate Institute of Natural Products, Chang Gung University, Kweishan, Taoyuan, Taiwan.
authors.forename: Zih-Chan
authors.initials: ZC
authors.lastname: Lin
authors.affiliation: Department of Respiratory Care, Chang Gung University of Science and Technology, Chiayi Campus, Chiayi, Taiwan.
authors.forename: Lee-Fen
authors.initials: LF
authors.lastname: Hsu
authors.affiliation: Research Center for Industry of Human Ecology, Chang Gung University of Science and Technology, Kweishan, Taoyuan Taiwan; Pharmaceutics Laboratory, Graduate Institute of Natural Products, Chang Gung University, Kweishan, Taoyuan, Taiwan; Department of Anesthetics, Chang Gung Memorial Hospital at Lin-Kou and College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan.
authors.forename: Jia-You
authors.initials: JY
authors.lastname: Fang
authors.affiliation: Center for Drug Abuse and Addiction, China Medical University Hospital, China Medical University, Taichung, Taiwan.
authors.forename: Yao-Chang
authors.initials: YC
authors.lastname: Chiang
authors.affiliation: Department of Pediatrics, Division of Neonatology and Pediatric Hematology/Oncology, Chang Gung Memorial Hospital, Yunlin, Taiwan.
authors.forename: Ming-Horng
authors.initials: MH
authors.lastname: Tsai
authors.affiliation: Division of Neurosurgery, Department of Surgery, Chang Gung Memorial Hospital, Chia-Yi 613 Taiwan.
authors.forename: Ming-Hsueh
authors.initials: MH
authors.lastname: Lee
authors.affiliation: Department of Pharmacy, College of Pharmacy & Health Care, Tajen University, Taiwan.
authors.forename: Shu-Yu
authors.initials: SY
authors.lastname: Li
authors.affiliation: Department of Dermatology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Dermatology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan. Electronic address: stephenhu30@hotmail.com.
authors.forename: Stephen Chu-Sung
authors.initials: SC
authors.lastname: Hu
authors.affiliation: School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan. Electronic address: ita0128@mail.cmu.edu.tw.
authors.forename: I-Ta
authors.initials: IT
authors.lastname: Lee
authors.affiliation: Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, No. 100, Tzyou 1st Road, Kaohsiung 807, Taiwan; Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung, Taiwan. Electronic address: flyen@kmu.edu.tw.
authors.forename: Feng-Lin
authors.initials: FL
authors.lastname: Yen
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D002460:Cell Line; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism*; D019610:Cytoprotection / Q000187:drug effects; D015232:Dinoprostone / Q000378:metabolism*; D015536:Down-Regulation; D004817:Epidermis / Q000187:drug effects / Q000201:enzymology; D047309:Flavones / Q000494:pharmacology*; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D008297:Male; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism; D052638:Particulate Matter / Q000633:toxicity*; D010766:Phosphorylation; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D000893:Anti-Inflammatory Agents; D047309:Flavones; D016328:NF-kappa B; D052638:Particulate Matter; D017382:Reactive Oxygen Species; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D020928:Mitogen-Activated Protein Kinases; C503624:eupafolin; D015232:Dinoprostone
keywords: Eupafolin; Eupafolin (PubChem CID: 5317284); Phyla nodiflora; cyclooxygenase-2; keratinocytes; particulate matter; prostaglandin E(2)