FIGURE 5.

JMJD3 overexpression aggravated DOX-induced cardiomyopathy in vitro and in vivo. NRCMs were infected with Ad-JMJD3 or Ad-GFP (empty vector) for 48 h. (A) Morphology of cardiomyocytes was observed by a light microscopy, scale bar = 50 μm. (B) Chromatin condensation was shown by Hoechst staining (indicated by arrows), scale bar = 50 μm. (C) The mitochondrial structure of cardiomyocytes was observed by mitotracker Red staining, scale bar = 25 μm. (D) Depolarization of mitochondria membrane potential was detected by TMRE-staining, scale bar = 100 μm. (E,F) The protein changes of BAX/Bcl-2 and cleaved caspase3 were analyzed by Western blot. Moreover, Ad-JMJD3 or Ad-GFP was transduced into the rat left ventricle via intramyocardial in situ injection. (G) The morphologic changes of gross hearts, scale bar = 5 mm. (H) Pathological changes of hearts tissues were detected by Masson-staining, scale bar = 100 μm. (I) Representative echocardiographic graphs. (J,K) EF (%) and FS (%) were analyzed by echocardiography, n = 8. The cardiac function was measured in 1, 2, and 3 weeks after the transfection of Ad-JMJD3 or Ad-GFP. (L) The protein expression of SESN2 was measured by Western blot. Data were presented as the mean ± SD. **p < 0.01, ***p < 0.001 vs. Ad-GFP group. n = 3. DOX, doxorubicin; EF, ejection fraction; FS, fractional shortening; JMJD3, Jumonji domain-containing 3; SESN2, Sestrin2; NRCMs, primary-cultured of neonatal rat cardiomyocytes; TMRE, tetramethyl rhodamine methyl ester.