3.2.1. Retinal pathophysiology: key features that need to be
represented in animal models
Diabetic retinopathy is the leading cause of visual impairment leading
to blindness impacting approximately one third of the diabetic
population[121]. Hyperglycaemia induced vascular damage involves
several metabolic pathways analogous to those affecting diabetic
nephropathy, including the polyol pathway, formation of AGEs and the PKC
pathway. These pathways accelerate the loss of pericytes, apoptosis of
endothelial cells, microaneurysms and thickening of the basement
membrane, resulting in capillary occlusions and ischaemia. These
processes trigger the upregulation of the growth factor VEGF, promoting
vascular permeability and angiogenesis. This contributes to the
progression of proliferative diabetic retinopathy and diabetic macular
oedema, ultimately leading to vision loss and blindness[122].