As a well-characterized member of the MAPK superfamily, JNK participates in the pathogenesis of cardiovascular diseases such as myocardial infarction, heart failure, myocardial ischemia-reperfusion (MI/R) injury, diabetic cardiomyopathy, dilated cardiomyopathy, and cardiac hypertrophy [43–47]. Here, MAPK8 is linked to heart failure.