INS and peripheral arterial disease: To make matters worse, decreased neutrophil apoptosis and the increase of lymphocyte apoptosis lead to abnormal cell ratio mediating insulin resistance and insulin secretion dysfunction, accelerating the production of more active oxidants, leading to permeability and dysfunction of vascular endothelial cells, decreased nitric oxide and capillary expansion, eventually reducing microcirculation to peripheral tissues (24), followed by atherosclerotic plaques and varying degrees of stenosis even up to occlusion (25), which we called PAD.