Fig. 5

GRAF1 depletion exacerbates cardiac fibrosis and reduces cardiac output in mdx mice. a Ventricle cross-sections from 6-month-old male mice with indicated genotypes stained with Sirius red and visualized using bright field microscopy (upper panels) or under polarized light (bottom panels). Note the fibrotic patches in double-depleted hearts (arrowheads). Scale bars = 1.0 mm. b Ventricle sections stained with Masson’s trichrome (MTC) reveals fibrosis as well as peri-vascular (asterisk) and interstitial inflammation (red arrowheads) in GRAF1/dystrophin-deficient hearts. Scale bars = 50 μm. c Percentage of mice with cardiac fibrosis at 6 months of age. Cross-sections of MTC-stained hearts were quantitated as follows: 1: 0–50 % peri-vascular fibrosis; minimal interstitial fibrosis; no scarring. 2: 50–80 % peri-vascular fibrosis; minimal interstitial fibrosis; no scarring. 3: 50–80 % peri-vascular fibrosis; intermediate interstitial fibrosis; some scarring. 4: 80–100 % peri-vascular fibrosis; significant interstitial fibrosis; significant scarring. d Average cardiomyocyte cross-sectional area (CSA) from hearts of 6-month-old mice. e–g Conscious echocardiographic analysis of left ventricular internal diameter (LVID) LV mass, ejection fraction (EF), and fractional shortening (FS), respectively, in 7-month-old female mice. (*p < 0.005, **p < 0.01, ^# p < 0.05; N = 4–5 mice per genotype). Data are represented as mean ± sem. Body weights for female mice were as follows and were not significantly different between groups Graf1^Wt/Wt; X^mdxX^mdx (30.4 ± 3.4 g); Graf1^Gt/Wt;X^mdxX^mdx (31.0 ± 3.4 g); Graf1^Gt/Gt;X^mdxX^mdx (31.1 ± 3.6)