GFAP and diabetes mellitus: Moreover, treatment with intravitreal injections of PEDF for 4 weeks in streptozotocin-induced diabetic rats ameliorates the diabetes-induced changes such as a decrease in a- and b-wave amplitude in electroretinogram, overexpression of glial fibrillary acidic protein (GFAP) in MGC, increase in VEGF, and disruption of BRB (Yoshida et al., 2009).