TNF and type 2 diabetes mellitus: According to Jariyapongskul et al. [53], the damage in the retinal microvasculature in type 2 diabetic rat model such as reduction of ocular blood flow (OBF) and leakage of the blood-retinal barrier (BRB) permeability is associated with hyperglycaemia and the accumulations of free radicals, advanced glycation end products (AGEs), receptor of advanced glycation end products (RAGE), tumour necrosis factor alpha (TNF-α), and vascular endothelial growth factor (VEGF) levels in the retinal tissues.