Fig 2: Western blotting assay of cTnT, cTnI, Bcl-2, Bax, and Caspase-3 expression. Results were shown as fold change compared with the expression of GAPDH. Data were shown as mean ± SD (n = 4). *P < 0.05, **P < 0.01, and ***P < 0.001 compared with the CON group; #P < 0.05, ##P < 0.01, and ###P < 0.001 compared with the EE group.

Fig 3: Exposure to SMG does not cause cytoskeletal deteriorations in CMs(A) A representative immunofluorescence staining of sarcomeric a-actinin (ACTN2) and cardiac troponin T (cTnT) in c-CMs and SMG-CMs (scale bar: 10 µm).(B) TEM images of SMG-CMs and c-CMs. Black arrow heads indicate caveolae structures (black arrows show stress fibers (scale bar: 500 nm).(C) Western blot analysis of Caveolin (CAV1) in control and SMG-exposed CMs (molecular weight of 22 kDa). GAPDH (36 kDa) was used as an internal protein loading control.

Fig 4: cTnT-immunostaining. (A) CTRL, (B) THIA, (C) DOX, and (D) DOX+THIA. Original magnification 20×.

Fig 5: Islet-1 induces the differentiation of C3H10T1/2 cells into cardiomyocytes. (A) The morphological alterations in C3H10T1/2 cells transfected with Lv-GFP or Lv-islet-1 were observed under a microscope. Scale bar=100 µm. (B) Expression of cTnT detected by immunofluorescence microscopy. Scale bar=100 µm. (C) Reverse transcription-quantitative polymerase chain reaction detected variations in mRNA expression levels of cardiac-specific transcription factors in C3H10T1/2 cells infected with lentiviral vectors containing Islet-1. *P<0.05 vs. blank group. Lv-GFP, lentiviral vector containing green fluorescent protein; Lv-islet-1, lentiviral vector containing Islet-1; cTnT, troponin T2 cardiac type; Nkx2.5, NK2 homeobox 5; GATA4, GATA binding protein 4; Mef2c, myocyte enhancer factor 2C; 1 W, 1 week; 2 W, 2 weeks; 3 W, 3 weeks; 4 W, 4 weeks.