Dysregulation of the OGF-OGFr pathway correlates with elevated serum OGF and ocular surface complications in the diabetic rat.

IMPACT STATEMENT: This research extends our knowledge about the presence and role of the OGF-OGFr regulatory axis in type 1 diabetes (T1D) and demonstrates specific targets within the pathway that are dysregulated. Serum levels of OGF, an inhibitory growth factor, are significantly elevated in male T1D rats, and OGFr serum values are increased in T1D. The onset of elevated OGF corresponds to the onset of ocular surface complications including dry eye, delayed corneal epithelial repair, and abnormal corneal surface sensitivity in T1D. Systemic insulin does not protect against elevated OGF levels or the onset of dry eye and sensitivity. These data are the first to associate some ocular surface defects in T1D with alterations in the OGF-OGFr pathway.