APLN and familial dilated cardiomyopathy: Furthermore, the alleviation of mitochondrial dysfunction in DCM by icariin was eliminated following an injection of Ad-sh-Apelin to db/db mice, as indicated by a greater decrease in mitochondrial protein expression (PGC‐1α, Mfn2, and Cyt-b) (Figures 4E, F P < 0.05), and increased production of ROS (Figure 4I).