title: Rosmarinic acid inhibits poly(I:C)-induced inflammatory reaction of epidermal keratinocytes.
abstract: OBJECTIVE
  Keratinocytes are the predominant cells in the epidermis, exerting their primary role of physical barrier through sophisticated differentiation process. In addition, keratinocytes contribute to the activation of innate immunity, providing the surveillant role against external pathogens. It has been known that chronic skin inflammatory disease such as psoriasis can be provoked by viral pathogens including double-stranded RNA. In this study, we demonstrated that rosmarinic acid (RA) has an inhibitory potential on inflammatory reaction induced by double-stranded RNA mimic poly(I:C) in epidermal keratinocytes.
  
  
  METHODS
  We cultured human epidermal keratinocytes and induced inflammatory reaction by poly(I:C) treatment. The effect of RA on inflammatory reaction of keratinocytes was determined by RT-PCR and Western blot.
  
  
  RESULTS
  RA significantly inhibited poly(I:C)-induced expression of inflammatory cytokines including IL-1β, IL-6, IL-8, CCL20, and TNF-α, and downregulated NF-κB signaling pathway in human keratinocytes. In addition, RA significantly inhibited poly(I:C)-induced inflammasome activation, in terms of secretion of active form of IL-1β and caspase-1. Furthermore, RA markedly inhibited poly(I:C)-induced NLRP3 and ASC expression.
  
  
  CONCLUSIONS
  These results indicate that RA can inhibit poly(I:C)-induced inflammatory reaction of keratinocytes, and suggest that it may be a potential candidate for the treatment of psoriasis.
authors.affiliation: Department of Dermatology, The Third Hospital of Jilin University, Changchun, Jilin 130033, China; Department of Dermatology, School of Medicine, Chungnam National University, Daejeon 35015, Korea.
authors.forename: Ming-Wei
authors.initials: MW
authors.lastname: Zhou
authors.affiliation: Department of Dermatology, The Third Hospital of Jilin University, Changchun, Jilin 130033, China.
authors.forename: Ri-Hua
authors.initials: RH
authors.lastname: Jiang
authors.affiliation: Department of Dermatology, School of Medicine, Chungnam National University, Daejeon 35015, Korea.
authors.forename: Ki-Duck
authors.initials: KD
authors.lastname: Kim
authors.affiliation: Department of Dermatology, School of Medicine, Chungnam National University, Daejeon 35015, Korea.
authors.forename: Jin-Hyup
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Dermatology, School of Medicine, Chungnam National University, Daejeon 35015, Korea.
authors.forename: Chang-Deok
authors.initials: CD
authors.lastname: Kim
authors.affiliation: Department of Orthopaedics, The Third Hospital of Jilin University, Changchun, Jirlin 130033, China. Electronic address: 109425381@qq.com.
authors.forename: Wei-Tian
authors.initials: WT
authors.lastname: Yin
authors.affiliation: Department of Dermatology, School of Medicine, Chungnam National University, Daejeon 35015, Korea; Skin Med Company, Daejeon 34028, Korea. Electronic address: jhoon@cnu.ac.kr.
authors.forename: Jeung-Hoon
authors.initials: JH
authors.lastname: Lee
mesh_terms: D002478:Cells, Cultured; D002934:Cinnamates / Q000494:pharmacology*; D016207:Cytokines / Q000378:metabolism; D053630:Depsides / Q000494:pharmacology*; D006801:Humans; D007249:Inflammation / Q000517:prevention & control*; D015603:Keratinocytes / Q000187:drug effects* / Q000378:metabolism; D011070:Poly I-C / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000097123:Rosmarinic Acid
chemical_list: D002934:Cinnamates; D016207:Cytokines; D053630:Depsides; D011070:Poly I-C; D000097123:Rosmarinic Acid
keywords: Inflammasome; Keratinocyte; Poly(I:C); Rosmarinic acid