NOS2 and osteoarthritis: The excessive NO formation by iNOS has been shown to be involved in several inflammatory and autoimmune diseases (septic shock, rheumatoid arthritis, osteoarthritis, and multiple sclerosis), but among these, it has been shown that iNOS activity can reduce insulin sensitivity via S-nytrosilation of insulin receptor and modulation of PPAR-γ activation [100, 101].