FSTL1 and type 2 diabetes mellitus: 107). Follicle-like protein 1 (FSTL1) is a glycosylated secretory protein produced by mesenchymal cell lines such as cardiomyocytes and fibroblasts. It is an acidic secretory protein rich in cysteine and is considered to be a beneficial regulator of cardiac fibrosis and insulin resistance. Recent studies have confirmed that the protective effect of FSTL1 in T2DM with MI was mediated by the USP10/Notch1 axis. Moreover, the inhibition of the USP10/Notch1 axis could counteract the myocardial protection of FSTL1 in T2DM (Ref. 108).