Proteomics reveals ablation of placental growth factor inhibits the insulin resistance pathways in diabetic mouse retina

The underlying molecular mechanisms that placental growth factor (PlGF) mediates the early complications at non-proliferative diabetic retinopathy (DR) remain largely elusive. The objective of this study is to characterize expression profile due to PlGF ablation in the retina of diabetic mice. The quantitative label-free proteomics was carried out on retinal tissues collected from mouse strains (Akita; PlGF −/− and Akita.PlGF −/− ). We have identified 3176 total proteins, and 107 were significantly different between the experimental groups, followed by gene ontology, functional pathways, and protein-protein network interaction analysis. Gnb1, Gnb2, Gnb4, Gnai2, Gnao1, Snap25, Stxbp1, Vamp2 and Gngt1 proteins are involved in insulin resistance pathways, which are down-regulated in PlGF ablation in Akita diabetics (Akita.PlGF −/− vs. Akita), up-regulation in Akita vs. C57, PlGF −/− vs. C57. Prdx6, Prdx5 (up-regulation) are known of antioxidant activity; Map2 is involved in neural protection pathways which are up-regulated in Akita.PlGF −/− vs. Akita. Our results suggest that inhibition of insulin resistance pathway and the enhancement of antioxidant defence and neural function may represent the potential mechanisms of anti-PlGF compounds in the treatment of DR.