Evaluation of early and late-life ACA and RAP treatment on age-related cardiac structural measures. At 22 months of age following the ACA or RAP treatment period, UM-HET3 male and female hearts were harvested. Whole hearts were weighed (A), and then micro dissected into component parts including left ventricles (LV) and right ventricles (RV) . (B and C). The change in early or late-life RAP-treated heart weights compared to controls remains significant after adjusting for body weight (D), while ACA treatment changes in heart weight are explained by changes in body weight (E). Data are presented as mean ± SEM. Group numbers: male controls (n = 20), male 4-month ACA (n = 17), male 16-month ACA (n = 9), male 4-month RAP (n = 15), male 16-month RAP (n = 13), female controls (n = 30), female 4-month ACA (n = 18), female 16-month ACA (n = 11), female 4-month RAP (n = 14), and female 16-month RAP (n = 12). ACA = acarbose; RAP = rapamycin; SEM = Standard Error of the Mean.