Among the several players that participate to the early vascular pathology that characterizes DR, vascular endothelial growth factor (VEGF) and its regulatory transcription factor hypoxia inducible factor-1 (HIF-1) play an important role and their increase takes place in response to hyperglycemia-induced hypoxic environment (Gu et al., 2019). Here, HIF1A is linked to Hyperglycemia.