Fig. 3.

αΒ-crystallin overexpression considerably improves cardiac function, survival rate during obligatory exercise and Des^−/− cardiomyocyte ultrastructural defects. Mice at 7 months of age were subjected to echocardiography. Des^−/−αBCry mice showed a significant improvement in left ventricular (LV) function reaching a fractional shortening (FS) value that was 96% of that of wild type (wt). (A) Representative M-mode echocardiograms from each mouse genotype. (B) Group data (mean±s.e.m) for left ventricular end diastolic diameter (a, LVEDD), end systolic diameter (b, ESD), FS (c), posterior wall dimension (d, PWd), ratio of left ventricular radius to PWd (e, r/h), ejection fraction (f, EF); *P<0.01, **P<0.001 and ***P<0.0001 vs Des^−/− (ANOVA with Bonferroni–Dunn post-hoc test). (C) Survival curve of 3-month-old wild-type (n=12), Des^−/− (n=12) and Des^−/−αBCry (n=13) mice during a swimming protocol. The error bars correspond to mean±s.e.m.; P<0.0001 Des^−/− vs wild type and Des^−/−αBCry at all time points (unpaired Student's t-test). (D) Myocardial tissue ultra-structure from 3-month-old mice that were examined by using transmission electron microscopy. Scale bar: 2 µm. (E) Higher magnification images of the myocardial mitochondria. Desmin deficiency affects the ultrastructure of the IMM, leading to excessive disorganization of cristae. The mitochondria from Des^−/−αΒCry transgenic myocardium appear normal. m, mitochondria; N, nucleus; c, cristae. Scale bars: 0.2 µm.