NOS3 and type 2 diabetes mellitus: We previously identified an adverse endothelial cell phenotype characterized by endothelial insulin resistance and lower NO production in patients with T2DM.23, 24, 25, 26, 27 The present study investigates the association of O‐GlcNAc with glucose levels and eNOS signaling in freshly isolated endothelial cells from patients with T2DM.