Finally, it should be noted that: 1) eNOS expression is stimulated by hypercholesterolemia, TNF-α, TGF-β and hypoxia; 2) NADPH oxidase expression is stimulated by glucose, FFA and cytokines in rat pancreatic islets and a clonal β-cell line [86]; and 3) high glucose levels downregulate the number of monocytic calveolae, which mediate the intracellular lipid transport, through NADPH oxidase-induced OS [87]. Here, TNF is linked to Hypercholesterolemia.