Voluntary Exercise Improves Cardiac Function and Prevents Cardiac Remodeling in a Mouse Model of Dilated Cardiomyopathy

Figure 1. Left ventricle function and structure assessments by echocardiography (A–E) and real-time PCR (F) in SRF-HKO and SRF-HKO wheel mice. (A–E) Evolution of left ventricle ejection fraction (LVEF), left ventricle shortening fraction (LVSF), thickness/radius ratio (h/r), end-systolic inter ventricular septum thickness (IVSs) and end-systolic left ventricle posterior wall thickness (LVPWs) before (baseline) and 40 days (sacrifice) after tamoxifen injections in SRF-HKO (n = 8) and SRF-HKO wheel (n = 9) mice. (F) Relative quantification by real-time PCR of Atrial Natriuretic Factor (ANF) and Brain Natriuretic Peptide (BNP) mRNA levels in myocardial tissue. Results are presented in-terms of a fold change to control after normalizing with Hmbs mRNA. The control mice value is set at 1.0. Results are expressed as mean values ± SEM. *p < 0.05; **p < 0.01.

Figure 2. Myocardial fibrosis quantification by PicroSirius Red staining (A,B) and real-time PCR analysis (C). (A,B) PicroSirius Red staining of transverse myocardium sections (A) and histogram representation (B) of fibrotic content in control (n = 3), SRF-HKO (n = 5) and SRF-HKO wheel (n = 6) mice. (C) Relative quantification by real-time PCR of collagen I (Col1a1), collagen III (Col3a1), connective tissue growth factor (CTGF) and transforming growth factor beta (TGFβ) mRNA levels in myocardial tissue. Results are presented in-terms of a fold change to control after normalizing with Hmbs mRNA. The control mice value is set at 1.0. Results are expressed as mean values ± SEM. **p < 0.01. Scale bar = 200 μm.

Figure 3. Real-time PCR (A,B) and Western blot analysis (C,D) of mitochondrial biogenesis and selected energetic pathways. (A,B) Relative quantification by real-time PCR of peroxysome proliferator-activated receptors alpha and gamma (PPARα/γ), PPAR gamma coactivators-1 alpha and beta (PGC1α/β), Transcription factor of activated mitochondria (TFAM), nuclear respiratory factor 1 (NRF1), nicotinamide phosphoribosyltransferase (NAMPT) and succinate deshydrogenase complex subunit (SDHA) mRNA levels in myocardial tissue. Results are presented in-terms of a fold change to control after normalizing with Hmbs mRNA. The control mice value is set at 1.0. (C,D) Western blot analysis (C) and histogram representation (D) of PGC1α, mitochondrial Aconitase (ACO2) and Voltage-Dependent Anion-selective Channel 1 (VDAC1) proteins quantification. Results are presented as a fold change to control after normalizing with GAPDH protein. The control mice value is set at 1.0. Results are expressed as mean values ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001.