ANGPT2 and diabetic retinopathy: Surprisingly, contradictory to these previous studies on diabetic retinopathy, glucosamine inhibits the protein expression of Ang2 in vitro in endothelial cells (both HUVECs and HRMVECs) despite the elevation of protein expression from high glucose, indicating that glucosamine-provoked vascular damage is presumably not initiated by pericyte loss.