MAPK8 and obesity due to melanocortin 4 receptor deficiency: WNT5a induces the non-canonical activation of JNK1, and SFRP5 deficient mice show highly activated JNK1 in HFD indicating that SFRP5 inhibits WNT5a mediated non-canonical JNK1 activation in adipose tissues to suppress obesity-induced inflammation and insulin resistance.