LAUSR

ABSTRACT Purpose To investigate the antioxidative effect and mechanism of pigment epithelium-derived factor (PEDF) on the ocular surface damage in diabetic mice. Methods C57BL/6 mice were injected intraperitoneally with streptozocin to generate diabetic models and then 50 nM PEDF or artificial tears were used to treat the diabetic mice. Treatment was given three times a day for eight weeks. Corneal epithelial damage, corneal sensitivity, and tear volume were quantified by fluorescein staining, esthesiometer, and phenol red cotton thread, respectively. Animals were sacrificed at 16 weeks after diabetes and the whole globe specimens were subjected to histochemical staining. Reactive oxygen species (ROS) generation was detected by 2ʹ,7-dichlorodihydrofluorescein probe. The levels of receptor for advanced glycation end products (RAGE) and superoxide dismutase 1 (SOD1) were examined by quantitative real-time PCR and western blotting. Results Topical application of PEDF improved corneal epithelial damage, increased corneal sensitivity, and tear volume in diabetic mice. ROS levels in the cornea were significantly higher in the diabetic mice than in the normal mice. Moreover, PEDF attenuated the accumulation of ROS, decreased the expression of RAGE, and elevated SOD1 expression in the cornea. Conclusions Topical application of PEDF can alleviate diabetes-related ocular surface damage and increase tear volume, along with the improvement of oxidative stress status.