Figure 5
Regulation of occludin expression in the diabetic retina by P60 and P78. (A) The confocal images show a decrease in occludin expression in diabetic Ins2Akita retinas (AT, vehicle treated) compared with ND controls (ND). Treatment with a combination of PEDF derivatives increased occludin expression in the retinal vasculature (arrow) of the diabetic animals (scale bar = 50 µmol/L) (n = 5). Western blot (B), densitometry measurements (C) and mRNA expression studies (D) confirm that the PEDF peptides significantly increased occludin levels in the diabetic retinas. P78 had a stronger effect than P60 in boosting both protein and mRNA expression (p ≤ 0.05). Differences between P78 and the combination peptide treatment were statistically insignificant. p values are indicated in the histograms where statistical significance was observed. All values are means ± SD.