MAPK8 and obesity due to melanocortin 4 receptor deficiency: In contrast, in obesity and insulin resistance, excess ROS have been shown to modify mitogen‐activated protein kinase (JNK, p38), SRC, and IKKβ signaling, either indirectly through oxidation of phosphatases and other endogenous inhibitors, or through direct oxidation of the kinase (Adler et al, 1999; Liu et al, 2000; Storz & Toker, 2003; Kamata et al, 2005; Kemble & Sun, 2009; Tiganis, 2011; Truong & Carroll, 2013).