Fig. 3: Myocardium-specific MAVS deficiency protects the heart at late stages of MIRI.

a Comparison of heart weight to body weight ratio at 14 days reperfusion in MAVS knockdown (MAVS-sh) mice and control mice (NC-sh). n = 5. b Wheat germ agglutinin staining of cardiac myocytes. Scale bar, 50 μm. c Cardiomyocyte size measured in myocardial tissue sections. n = 20 cells/group. d Echocardiography of MAVS-sh and NC-sh mice at day 14 after reperfusion. Yellow line shows left ventricle wall positions, white double-tailed arrow represents the inner diameter. LVIDS, Left ventricular internal diameter end systole; LVIDD, Left ventricular internal diameter end diastole. Scale bar, 1 mm. e Left ventricular ejection fraction (LVEF), left ventricular fraction shortening (LVFS), left ventricular end-systolic volume (LVESV) and left ventricular end-diastolic volume (LVEDV) were assayed to determine cardiac function in MAVS-sh and NC-sh mice at day 14 after reperfusion or sham. n = 5. f Fibrosis of heart tissue sections at day 14 after reperfusion. Pathological parameters are shown in remote area, area at risk and infarct area. Scale bar, 1 mm (panoramic), 50 μm (enlarged). g Fibrosis proportion in infarct area in f was calculated. n = 8. h Immunofluorescence staining of endothelial cell marker CD31 in cardiac tissues at day 14 after reperfusion. Scale bar, 20 μm. i Blood vessels number in high power fields was counted according to the staining results in (h). n = 8. Data are presented as means ± standard deviation; *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001 by one-way analysis of variance with Tukey’s multiple comparisons test (a, c, e); *p < 0.05, ***p < 0.001 by unpaired 2-tailed Student t test (g, i); ns, p ≥ 0.05. Source data are provided as a Source Data file.