Fig. 1

Protocol figure. Mice were divided into eight groups (n = 12/group). Male and female wild-type mice on a standard chow diet were used as healthy controls (SD/WT). Sex-matched APOB-100 mice were fed with a high-fat diet (to induce MetS and cardiovascular abnormalities (HFD/APOB-100). Both control and APOB-100 mice were divided into sedentary and exercise groups trained by treadmill running, five times a week, for 45 min per occasion, at a speed of 0.9 km/h. Dietary intervention and ET started at the age of 3 months and lasted for 7 months. At 9 months of age, transthoracic echocardiography was performed. At 10 months of age, all mice were terminally anesthetized by sodium pentobarbital, and fasting blood samples were collected through a cardiac puncture to measure serum low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol, blood glucose, and serum insulin levels. Before removing hearts, transcardial perfusion was performed. Weights of the hearts were measured, and then left and right ventricles were separated. Then a subgroup of left ventricular samples (n = 6/group) was frozen in liquid nitrogen for RNA isolation, and another subgroup of left ventricles (n = 6/group) was fixed in 4% paraformaldehyde