Dataset Information

Alteration of galectin-3 in tears of patients with dry eye disease.

ABSTRACT: To investigate the expression, release, and proteolytic degradation of galectin-3 in patients with dry eye disease.Observational case series with a comparison group.Tear washes and conjunctival impression cytology specimens were collected through standard procedures from 16 patients with dry eye and 11 age-matched healthy subjects. Galectin-3 content in tears was analyzed by quantitative Western blot, using recombinant galectin-3 protein to generate a calibration curve. The relative expression of galectin-3 and matrix metalloproteinase 9 (MMP9) was evaluated by quantitative polymerase chain reaction. The cleavage of galectin-3 was studied in vitro using activated recombinant MMP9 and protease inhibitors.The concentration of galectin-3 protein in tears, but not galectin-3 expression in conjunctival epithelium, was significantly higher in tears of patients with dry eye (0.38 ng/?g total protein, range 0.04-1.36) compared to healthy subjects (0.12 ng/?g total protein, range 0.00-0.41) (P < .01). By Western blot, an intact (?28.0 kDa) galectin-3 band was identified in tear samples from healthy subjects, whereas 50% of the dry eye samples were characterized by the additional presence of a partially degraded form (?25.4 kDa). In our experiments, elevated expression of MMP9 in dry eye subjects correlated with the ability of active MMP9 to cleave galectin-3 from recombinant origin. Interestingly, cleavage of endogenous galectin-3 in tear samples was impaired using a broad-spectrum proteinase inhibitor cocktail, but not the pan-specific MMP inhibitor GM6001, suggesting the presence of proteases other than MMPs in promoting galectin-3 degradation in dry eye.Our results indicate that release of cellular galectin-3 into tears is associated with epithelial dysfunction in dry eye, and that galectin-3 proteolytic cleavage may contribute to impaired ocular surface barrier function.

SUBMITTER: Uchino Y

PROVIDER: S-EPMC4426220 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Alteration of galectin-3 in tears of patients with dry eye disease.

Uchino Yuichi Y Mauris Jerome J Woodward Ashley M AM Dieckow Julia J Amparo Francisco F Dana Reza R Mantelli Flavio F Argüeso Pablo P

American journal of ophthalmology 20150219 6

<h4>Purpose</h4>To investigate the expression, release, and proteolytic degradation of galectin-3 in patients with dry eye disease.<h4>Design</h4>Observational case series with a comparison group.<h4>Methods</h4>Tear washes and conjunctival impression cytology specimens were collected through standard procedures from 16 patients with dry eye and 11 age-matched healthy subjects. Galectin-3 content in tears was analyzed by quantitative Western blot, using recombinant galectin-3 protein to generate ...[more]

PMID: 25703476

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Alteration of galectin-3 in tears of patients with dry eye disease.

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Alteration of galectin-3 in tears of patients with dry eye disease.

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