title: Tear cytokine and ocular surface alterations following brief passive cigarette smoke exposure.
abstract: OBJECTIVE
  To prospectively investigate the effects of acute passive cigarette smoke exposure on the ocular surface and tear film in healthy non-smokers.
  
  
  METHODS
  Twelve right eyes of 12 subjects without any ocular diseases were examined before, 5 min, and 24h after 5 min of passive cigarette smoke exposure in a controlled smoke chamber. Tear samples were obtained before, 5 min and 24 h after smoke exposure to detect tear hexanoyl-lysine (HEL), acrolein and inflammatory cytokine concentrations. Tear evaporation rate, DR-1 tear film lipid layer interferometry, tear film break-up time (TBUT), ocular surface fluorescein staining (FS) and Rose Bengal staining (RB), Schirmer I test were performed before, 5 min, and 24h after smoke exposure. Conjunctival impression cytology (IC) and brush cytology (BC) were carried out before and 24h after smoke exposure.
  
  
  RESULTS
  Tear evaporation rate, tear lipid spread time, tear film break-up time, and vital staining scores showed significant worsening with passive smoke exposure. Tear HEL and IL-6 concentrations increased significantly 24 h after smoke exposure. Tear acrolein level showed an insignificant increase at 5 min. IC and RT-PCR revealed a significant reduction in goblet cell density, a shift toward higher squamous metaplasia grades and a significant downregulation of MUC5AC mRNA expression at 24 h.
  
  
  CONCLUSIONS
  Even brief passive exposure to cigarette smoke in healthy non-smoker subjects was associated with adverse effects on the ocular surface health as evidenced by an increase of tear inflammatory cytokines, tear lipid peroxidation products and decrease of mucosal defense resulting in tear instability and damage to the ocular surface epithelia.
authors.affiliation: Keio University School of Medicine, Johnson & Johnson Ocular Surface and Visual Optics Department, Shinanomachi 35, Shinjuku-ku, Tokyo, Japan.
authors.forename: Van Tuan
authors.initials: VT
authors.lastname: Rummenie
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Matsumoto
authors.forename: Murat
authors.initials: M
authors.lastname: Dogru
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Yiqian
authors.initials: Y
authors.lastname: Hu
authors.forename: Samantha K
authors.initials: SK
authors.lastname: Ward
authors.forename: Ayako
authors.initials: A
authors.lastname: Igarashi
authors.forename: Tais
authors.initials: T
authors.lastname: Wakamatsu
authors.forename: Osama
authors.initials: O
authors.lastname: Ibrahim
authors.forename: Eiki
authors.initials: E
authors.lastname: Goto
authors.forename: Gré
authors.initials: G
authors.lastname: Luyten
authors.forename: Hiroko
authors.initials: H
authors.lastname: Inoue
authors.forename: Ichiro
authors.initials: I
authors.lastname: Saito
authors.forename: Jun
authors.initials: J
authors.lastname: Shimazaki
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tsubota
mesh_terms: D000171:Acrolein; D000328:Adult; D002248:Carbon Monoxide; D048430:Cell Shape; D016207:Cytokines / Q000378:metabolism*; D005123:Eye / Q000166:cytology / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008239:Lysine / Q000378:metabolism; D008297:Male; D055271:Mucin 5AC; D009077:Mucins / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D012907:Smoking; D013666:Tears / Q000378:metabolism*; D018417:Th1 Cells / Q000378:metabolism; D018418:Th2 Cells / Q000378:metabolism; D013997:Time Factors; D014835:Volatilization
chemical_list: D016207:Cytokines; C524678:MUC5AC protein, human; D055271:Mucin 5AC; D009077:Mucins; C120589:N(epsilon)-hexanoyllysine; D012333:RNA, Messenger; D000171:Acrolein; D002248:Carbon Monoxide; D008239:Lysine