Administration of Cy3G attenuates cardiac dysfunction and cardiac inflammation in STZ-induced diabetic cardiomyopathy and decreases collagen disposition via activation of matrix metalloproteinase-9 (MMP-9) and reduction in the level of tissue inhibitor of matrix metalloproteinase (TIMP)-1 observed in diabetic rat heart (Chen et al., 2016). This evidence concerns the gene MMP9 and diabetic cardiomyopathy.