JUN and obesity due to melanocortin 4 receptor deficiency: In a mice model of obesity-induced myocardial dysfunction, treatment with TUDCA resulted in increased expression and activity of sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) and alleviation of augmented levels of p-IRSSer307, cJun, p-cJun, p-JNK, and ER stress markers [98,104,121].