TRIM63 and heart failure: (2) Muscle mass is already higher in the MuRF1KO and MuRF2KO animals when compared to WT mice independent of heart failure induction, (3) muscle atrophy induced by MCT goes along with the activation of MuRF1, MuRF2, and MAFbx, and a downregulation of enzymes involved in mitochondrial energy production and energy transfer, (4) the expression of MuRF1 influences also the expression of MuRF2.