Fig. 4

Erastin abolishes the protective effect of irisin on diabetic cardiomyopathy. Type 1 diabetic mice were treated with irisin (10 μg/kg body weight/day) in the presence or absence of the ferroptosis inducer erastin (40 mg/kg body weight/day, 3 consecutive days for 4 weeks). A1. Representative echocardiographic images from a mouse in each of the five groups of mice. Quantification of (A2) LVEF%, (A3) LVFS%, (A4) LVIDd, and (A5) LVIDs are shown (n = 6 per group). B Representative Masson staining images of heart tissues from a mouse in each of the five groups of mice: (B1) quantification (B2) of the fibrotic area (Scale bar = 50 μm; n = 6 per group). C Representative TEM images from the heart of a mouse in each of the five groups of mice (C1) and corresponding relative Flameng scores (Bottom) (C2) of the mitochondria in myocardial tissues of each group (Scale bars = 500 nm; n = 6 per group). Data are presented as the mean ± SD. One-way ANOVA, and Bonferroni’s post-hoc test. ^*P < 0.05, ^**P < 0.01. STZ streptozotocin, LVEF left ventricular ejection fraction, LVFS left ventricular fractional shortening, LVIDd left ventricular internal diameter at end-diastole, and LVIDs left ventricular internal diameter at end-systole, TEM transmission electron microscopy