title: Effects of Quercetin in a Mouse Model of Experimental Dry Eye.
abstract: OBJECTIVE
  To evaluate the effect of treatment with quercetin in a mouse model of dry eye.
  
  
  METHODS
  0.5% quercetin eye drops were prepared and an experimental dry eye model was induced in NOD.B10.H2(b) mice through desiccation stress. The mice were divided into 3 groups according to the treatment regimen: the DS 10D group (desiccation stress for 10 days), the phosphate buffered saline (PBS) group, and the quercetin group. Tear volumes and corneal irregularity scores were measured at 3, 5, 7, and 10 days after treatment. Hematoxylin and eosin staining, periodic acid-Schiff staining, and immunohistochemistry were performed at the end of the experiment.
  
  
  RESULTS
  The quercetin group had increased tear volumes (0.2 ± 0.03 μm, P < 0.05) and decreased corneal irregularity scores (0.7 ± 0.6, P < 0.05) compared with those of the PBS group. On histological examination, the quercetin group exhibited restored smooth corneal surfaces without detaching corneal epithelial cells and had significantly increased goblet cell density (13.8 ± 0.8 cells/0.1 mm², P < 0.05) compared with the PBS group. The quercetin group also exhibited significant declines of MMP-2 (5.1-fold of control, P < 0.01), MMP-9 (2.5-fold of control, P < 0.01), ICAM-1 (2.2-fold of control, P < 0.01), and VCAM-1 (2.3-fold of control, P < 0.01) levels in the lacrimal gland than did the PBS group.
  
  
  CONCLUSIONS
  Topical application of quercetin can help to improve ocular surface disorders of dry eye not only by decreasing the corneal surface irregularity but also by increasing the tear volume and goblet cell density. Moreover, quercetin has the potential for use in eye drops as a treatment for dry eye disease with antiinflammatory effects on the lacrimal functional unit.
authors.affiliation: *Department of Ophthalmology, Inje University College of Medicine, Inje University Busan Paik Hospital, Busan, Korea; and †Ocular Neovascular Disease Research Center, Inje University Busan Paik Hospital, Busan, Korea.
authors.forename: Ha Na
authors.initials: HN
authors.lastname: Oh
authors.forename: Chae Eun
authors.initials: CE
authors.lastname: Kim
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Jae Wook
authors.initials: JW
authors.lastname: Yang
mesh_terms: D000287:Administration, Topical; D000818:Animals; D000975:Antioxidants / Q000627:therapeutic use*; D003228:Conjunctiva / Q000166:cytology; D003315:Cornea / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology; D004195:Disease Models, Animal; D015352:Dry Eye Syndromes / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D019573:Epithelium, Corneal / Q000187:drug effects / Q000378:metabolism; D020397:Goblet Cells / Q000187:drug effects / Q000378:metabolism; D007150:Immunohistochemistry; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D051379:Mice; D016688:Mice, Inbred NOD; D009883:Ophthalmic Solutions; D011794:Quercetin / Q000627:therapeutic use*; D013666:Tears / Q000502:physiology*; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism
chemical_list: D000975:Antioxidants; D009883:Ophthalmic Solutions; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1; D011794:Quercetin; D020778:Matrix Metalloproteinase 2; C522362:Mmp2 protein, mouse; D020780:Matrix Metalloproteinase 9; C501830:Mmp9 protein, mouse