Fig. 2.

Irisin decreased cardiomyocyte apoptosis and fibrosis in post-MI hearts. a Representative images and quantification of apoptosis indicator TUNEL-positive cardiomyocytes and noncardiomyocyte in heart tissue at 2 days post-MI. Cardiomyocytes were indicated with cTnT staining, and nuclei were stained with DAPI, scale bar = 20 μm. A arrow indicates noncardiomyocyte; a triangle indicates cardiomyocyte. b Representative images and quantification of fibrosis of infarct border zone at 4 weeks post-MI detected with Masson trichrome staining. Scale bar = 50 μm. c Representative images and quantification of cardiomyocyte proliferation at 7 days post-MI, indicated by Ki67 immunostaining. n = 6. scale bar = 20 μm. *P < 0.05 vs. control