Fig. 3

Insulin eye drops improve corneal nerve regeneration. (A) The typical changes of regenerated nerve fibers in the cornea after the administration of insulin by using β3-tubulin (red), a pan-neuronal marker, immunofluorescence in the whole-mount cornea (n = 3). (B) Representative corneal cross-sections further show the locations and the regeneration (white arrows) of the central corneal epithelial nerve costaining with β3-tubulin (red) and DAPI (blue), (n = 3). (C) The length of corneal nerve fibers (µm/µm2) in the central and peripheral areas was calculated using Neuron J software. (D) The dynamic changes of corneal sensation (mm) in two groups at 0 h and 72 h. Data were exhibited as mean ± SD; *P < 0.05. Scale bars: 500 μm, 100 μm, and10µm. DM-In, diabetic mice with topical insulin treatment; DM-Con, diabetic mice with topical physiological saline treatment; Ep, corneal epithelium; St, corneal stroma