Fig. 1. Castration of male mice reduces neutrophilia, cardiac injury, and cardiac remodeling and increases survival after an acute MI.

a–d Neutrophil counts in blood, area at risk (AAR) and MI size after 45 min ischemia followed by 24 h reperfusion. a, b Male and female mice; a *P = 0.038 (two-sided unpaired Student t test), n = 5 + 4; b ***P < 0.0001 (two-sided unpaired Student t test), n = 10 + 7. c, d Sham-castrated (control) and castrated (orchiectomized; ORX) male mice; c P = 0.057, n = 4 + 4 (two-sided Mann–Whitney); d **P = 0.0095 (two-sided Mann−Whitney), n = 4 + 6. e–g MI was induced by permanent ligation of the left coronary artery in ORX or sham-castrated (control) mice. 48 h after MI or sham-MI (S-MI) surgery, neutrophils (e), monocytes (f), and macrophages (g) were quantified in the left ventricle (LV) by flow cytometry. e *P = 0.017 and **P = 0.004 (two-sided unpaired Student t test). e–g n = 5 + 5 and 9 + 9 for S-MI and MI, respectively. h–l MI was induced by permanent ligation of the left coronary artery in ORX or sham-castrated (control) mice. Echocardiography was performed before MI (baseline; BL) and 24 h and 3 weeks post-MI. h The area at risk analyzed at 24 h post-MI. i Survival rate; P = 0.050 (log-rank test). j Cardiac rupture rate during the 3 weeks of follow-up; *P = 0.044 (two-sided Fisher´s test); h–j n = 18 + 14. LV volume in diastole at BL, 24 h and 3 weeks post-MI; n = 9 + 9 (BL), 10 + 12 (24 h), and 9 + 12 (3w), 3w, *P = 0.042 (two-sided unpaired Welch´s t test). l Representative echocardiographic images in sham-operated (control) and castrated (ORX) mice at 24 h and 3 weeks post-MI, scale bar = 1 mm. m, n Male mice were castrated and treated with vehicle (V) or testosterone (T) for 3 weeks before permanent ligation of the left coronary artery. 24 h after MI, plasma was assessed for myeloperoxidase (MPO), m *P = 0.050 (two-sided unpaired Student t test) and cardiac troponin I (cTnI), n; *P = 0.015 (two-sided unpaired Student t test); m, n; n = 8 + 9. Bars indicate means (a, b, e–g, k, m, n) or medians (c, d), error bars are SEM (a, b, e–g, k, m, n) or interquartile ranges (c, d), and circles represent individual mice. Source data are provided as Source data file.