MAPK8 and obesity due to melanocortin 4 receptor deficiency: The protective effect of C66 on obesity-induced cardiomyopathy through inhibition of JNK-mediated inflammation was investigated. Male C57BL/6 mice were fed HFD for 11 weeks followed by oral administration with 5, 10, and 20 mg/kg of C66 every 2 days for a further 7 weeks during HFD feeding.