title: Diquafosol Tetrasodium Increases the Concentration of Mucin-like Substances in Tears of Healthy Human Subjects.
abstract: OBJECTIVE
  This study was undertaken to determine the effect of topical application of diquafosol tetrasodium on proteins and mucin-like substances from tears of clinically healthy subjects.
  
  
  METHODS
  Tears were collected from both the eyes of 10 healthy volunteers. Diquafosol tetrasodium solution (3%) was applied once to the right eye and 0.9% sodium chloride solution (saline) once to the left eye. Tear samples were collected by Schirmer test strips before application and 5, 15, 30 and 60 min after application. Sialic acid, a marker of mucin-like substances, and major tear proteins including secretory IgA, lactoferrin, lipocalin-1, and lysozyme were measured by high performance liquid chromatography.
  
  
  RESULTS
  Levels of total protein, sIgA and lysozyme were transiently decreased in both groups but returned to baseline levels within 15 min after application. The concentration of lactoferrin and lipocalin-1 did not change significantly in both groups. Sialic acid in tears was significantly decreased 5 min after saline application, but significantly increased 5 min after diquafosol application. No significant difference in sialic acid was seen after 15 min in both groups.
  
  
  CONCLUSIONS
  Topical application of saline and diquafosol resulted in transient decrease of tear proteins possibly due to wash out or dilution effects. In contrast, diquafosol application significantly increased sialic acid, although the effect was transient. This suggests diquafosol stimulates the secretion of mucins from ocular tissues of healthy human subjects.
authors.affiliation: Division for Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center , Higashigaoka, Meguro-ku, Tokyo , Japan and.
authors.forename: Chika
authors.initials: C
authors.lastname: Shigeyasu
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Hirano
authors.forename: Yoko
authors.initials: Y
authors.lastname: Akune
authors.forename: Masakazu
authors.initials: M
authors.lastname: Yamada
mesh_terms: D000328:Adult; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005500:Follow-Up Studies; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D009077:Mucins / Q000187:drug effects / Q000378:metabolism*; D009883:Ophthalmic Solutions; D011122:Polyphosphates / Q000008:administration & dosage*; D013666:Tears / Q000737:chemistry*; D014500:Uracil Nucleotides / Q000008:administration & dosage*
chemical_list: D009077:Mucins; D009883:Ophthalmic Solutions; D011122:Polyphosphates; D014500:Uracil Nucleotides; C403315:diquafosol
keywords: Diquafosol tetrasodium; dry eye; mucins; sialic acid; tears