Fig. 1. Absence of endothelial Sirt1 in male mice stimulates insulin sensitivity.

a Glucose tolerance test in Sirt1^fl/fl mice (n = 7) vs. KO mice (n = 9), *p < 0.05. b Insulin tolerance test in Sirt1^fl/fl mice (n = 10) vs. KO mice (n = 8), *p <  0.05. c Glucose infusion rates during hyperinsulinemic-euglycemic clamps in Sirt1^fl/fl mice (n = 14) vs. KO mice (n = 11), *p  <  0.05). d Serum insulin levels during glucose tolerance test in Sirt1^fl/fl mice (n = 8) vs. KO mice (n = 10), (p  >  0.05). e Insulin-stimulated glucose uptake in tissues of Sirt1^fl/fl mice (n = 9) vs. KO mice (n = 6), ns p > 0.05^, *p = 0.022. f Basal and insulin-stimulated Akt phosphorylation in gastrocnemius muscle of Sirt1^fl/fl mice (n = 6), Sirt1^fl/fl-insulin mice (n = 6), KO mice (n = 5), and KO-insulin mice (n = 7). g IR/IGF1R phosphorylation in gastrocnemius of Sirt1^fl/fl mice (n = 6) vs. KO mice (n = 6). ns p > 0.05. h Respiratory exchange ratio (RER) in Sirt1^fl/fl (n = 10) and KO mice (n = 13). p = 0.044. Data are shown as mean ± SEM. Two-tailed unpaired Student’s t test was used. In (a, b, c, d, and h), black line represents Sirt1^fl/fl mice, and blue line represents KO mice. In (e, f, and g), gray bar represents Sirt1^fl/fl mice, and blue bar represents KO mice. Each dot represents one mouse. Sirt1^fl/fl Sirt1^flox/flox mice, and KO E-Sirt1-KO mice. Source data are provided as a Source Data file.