TGFB1 and familial dilated cardiomyopathy: We also confirmed that fibrosis plays a role in the development of diabetic cardiomyopathy, as evidenced by the accumulation of collagen in the myocardial interstitial and perivascular region in the heart tissues of DCM rats, as well as the increase in transcription and protein expression of Col1, Col3, α-SMA, and TGF-β1 both in vivo and in vitro, findings that were in line with previous studies (Huynh et al., 2014; Wang Y. H. et al., 2021b).