title: Anti-inflammatory effects of hinokitiol on human corneal epithelial cells: an in vitro study.
abstract: OBJECTIVE
  This study assessed the anti-inflammatory effect and mechanism of action of hinokitiol in human corneal epithelial (HCE) cells.
  
  
  METHODS
  HCE cells were incubated with different concentrations of hinokitiol or dimethylsulfoxide (DMSO), which served as a vehicle control. Cell viability was evaluated using Cell Counting Kit-8 (CCK-8) assay. After polyriboinosinic:polyribocytidylic acid (poly(I:C)) stimulus, cells with or without hinokitiol were evaluated for the mRNA and protein levels of interleukin-8 (IL-8), interleukin-6 (IL-6), and interleukin-1β (IL-1β) using real-time PCR analysis and an enzyme-linked immunosorbent assay (ELISA), respectively. Nuclear and cytoplasmic levels of nuclear factor kappa B (NF-κB) p65 protein and an inhibitor of NF-κB α (IκBα) were evaluated using western blotting.
  
  
  RESULTS
  There were no significant differences among the treatment concentrations of hinokitiol compared with cells incubated in medium only. Incubating with 100 μM hinokitiol significantly decreased the mRNA levels of IL-8 to 58.77±10.41% (P<0.01), IL-6 to 64.64±12.71% (P<0.01), and IL-1β to 54.19±8.10% (P<0.01) compared with cells stimulated with poly(I:C) alone. The protein levels of IL-8, IL-6, and IL-1β had similar trend. Further analysis revealed that hinokitiol maintained the levels of IκBα and significantly reduced NF-κB p65 subunit translocation to the nucleus which significantly inhibiting the activation of the NF-κB signal pathway.
  
  
  CONCLUSIONS
  Hinokitiol showed a significant protective effect against ocular surface inflammation through inhibiting the NF-κB pathway, which may indicate the possibility to relieve the ocular surface inflammation of dry eye syndrome (DES).
authors.affiliation: Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China.
authors.forename: J
authors.initials: J
authors.lastname: Ye
authors.affiliation: Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Y-F
authors.initials: YF
authors.lastname: Xu
authors.affiliation: Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China.
authors.forename: L-X
authors.initials: LX
authors.lastname: Lou
authors.affiliation: Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China.
authors.forename: K
authors.initials: K
authors.lastname: Jin
authors.affiliation: Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Q
authors.initials: Q
authors.lastname: Miao
authors.affiliation: Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China.
authors.forename: X
authors.initials: X
authors.lastname: Ye
authors.affiliation: Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Xi
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D015153:Blotting, Western; D002460:Cell Line; D002470:Cell Survival; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D019573:Epithelium, Corneal / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D020869:Gene Expression Profiling; D006801:Humans; D053583:Interleukin-1beta / Q000235:genetics / Q000378:metabolism; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D016209:Interleukin-8 / Q000235:genetics / Q000378:metabolism; D039821:Monoterpenes / Q000494:pharmacology*; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D011070:Poly I-C / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D014334:Tropolone / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D000890:Anti-Infective Agents; D000894:Anti-Inflammatory Agents, Non-Steroidal; C508606:CXCL8 protein, human; C508600:IL6 protein, human; D053583:Interleukin-1beta; D015850:Interleukin-6; D016209:Interleukin-8; D039821:Monoterpenes; D016328:NF-kappa B; D012333:RNA, Messenger; D014334:Tropolone; D011070:Poly I-C; C009479:beta-thujaplicin; D004121:Dimethyl Sulfoxide