INS and obesity due to melanocortin 4 receptor deficiency: Compromised endothelial function in obesity and diabetesThe vasculature of obese and diabetic subjects has a reduced baseline ACE2 expression, which leads to a compromised endothelial function and increased vascular permeability. This dysfunction can be further increased through virally-mediated reduction of ACE2. Administration of insulin and other anti-diabetic drugs causes additional suppression of ACE2.