OPN3 and Insulin resistance: CPR, ER-localized NADPH-dependent oxygenase (NOX4)59 and other NADPH-linked oxidative folding machinery such as protein disulfide isomerase (PDI) and endoplasmic reticulum oxidoreductase (ERO)60 are possible candidate proteins for intra-ER-originating ROS-linked protein folding alterations, which lead to ER stress and hepatic dyslipidemic insulin resistance.