Osthole attenuates trastuzumab-induced cardiotoxicity in mice by enhancing autophagy via regulating the p38MAPK/mTOR signaling pathway

Figures

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  Fig. 1. Chemical structure of OST.

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  Fig. 2. Effects of OST on the general phenotype in TRZ-treated mice. (A) The ratio of heart weight (HW) to body weight (BW). (B–E) Serum LDH, CK, CK-MB and cTnI levels in mice. (F) Representative images of H&E staining. (G) Representative images of Masson staining. (H) Fibrosis area analysis of Masson staining (200 × magnification). Results are presented as means ± SEM (n = 3/6). ##P < 0.01 vs the CON group; ∗P < 0.05, ∗∗P < 0.01 vs the TRZ group.

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  Fig. 3. Effects of OST on cardiac dysfunction in TRZ-treated mice. (A) Representative echocardiographic M-mode images of each group. (B–G) The parameters of LVEF, LVFS, LVIDd, LVIDs, LVPWd and LVPWs measured by echocardiography. Each column is mean ± SEM (n = 5). #P < 0.05, ##P < 0.01 vs the CON group; ∗P < 0.05, ∗∗P < 0.01 vs the TRZ.

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  Fig. 4. Effects of OST on oxidative stress in TRZ-treated mice. (A) The representative images of DHE staining (200 × magnification). (B) Quantitative analysis of fluorescence intensity by DHE staining. (C) SOD activity of cardiac tissues. (D) MDA level of cardiac tissues. Data are expressed as means ± SEM (n = 3). ##P < 0.01 vs the CON group; ∗P < 0.05, ∗∗P < 0.01 vs the TRZ group.

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  Fig. 5. Effects of OST on cardiomyocyte apoptosis in TRZ-treated mice. (A) Representative images of TUNEL staining (200 × magnification). (B) The apoptosis rate of each group by TUNEL staining. Data are expressed as means ± SEM (n = 3). (C) Representative western blotting bands for Bax, Bcl-2 and Caspase-3. (D–E) Quantitative analysis of Bax/Bcl-2 and Caspase-3 (normalized to GAPDH). Data are expressed as means ± SEM (n = 3). ##P < 0.01 vs the CON group; ∗P < 0.05, ∗∗P < 0.01 vs the TRZ group.

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  Fig. 6. Effects of OST on cardiac autophagy and the p38MAPK/mTOR signaling pathway in TRZ-treated mice. (A–B) Representative images of transmission electron microscopy images, yellow arrow, mitochondria; red arrow, autophagosome. (C) Representative western blotting bands for LC3I, LC3II, Beclin-1, p62. (D–F) Quantitative analysis of LC3II/I, Beclin-1, p62 (normalized to GAPDH). (G) Representative western blotting bands for p-p38MAPK, p38MAPK, p-mTOR and mTOR. (H) Quantitative analysis of p-p38MAPK/p38MAPK and p-mTOR/mTOR. Data are expressed as means ± SEM (n = 3). ##P < 0.01 vs the CON group; ∗P < 0.05, ∗∗P < 0.01 vs the TRZ group.

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  Fig. 7. Effects of OST on oxidative stress and apoptosis in TRZ-treated mice after 3-MA administration. (A–B) Representative western blotting bands and quantitative analysis of Bax/Bcl-2 and Caspase-3 (normalized to GAPDH). (C) SOD activity of cardiac tissues. (D) MDA level of cardiac tissues. Data are expressed as means ± SEM (n = 3/6). ##P < 0.01 vs the CON group; ∗∗P < 0.01 vs the TRZ group; ▲P < 0.05, ▲▲P < 0.01 vs the TRZ + OST H group.

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  Fig. 8. Effects of OST on oxidative stress and apoptosis in TRZ-treated mice after SB203580 administration. (A–B) Representative western blotting bands and quantitative analysis of Bax/Bcl-2 and Caspase-3 (normalized to GAPDH). (C) SOD activity of cardiac tissues. (D) MDA level of cardiac tissues. Data are expressed as means ± SEM (n = 3/6). ##P < 0.01 vs the CON group; ∗P < 0.05, ∗∗P < 0.01 vs the TRZ group; ▲P < 0.05, ▲▲P < 0.01 vs the TRZ + OST H group.

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  Fig. 9. Effects of OST on autophagy and the p38MAPK/mTOR signaling pathway in TRZ-treated mice after SB203580 administration. (A–B) Representative images of transmission electron microscopy images, yellow arrow, mitochondria; red arrow, autophagosome. (C) Representative western blotting bands for LC3I, LC3II, Beclin-1, p62. (D–F) Quantitative analysis of LC3II/I, Beclin-1, p62 (normalized to GAPDH). (G) Representative western blotting bands for p-mTOR and mTOR. (H) Quantitative analysis of p-mTOR/mTOR. Data are expressed as means ± SEM (n = 3). #P < 0.05, ##P < 0.01 vs the CON group; ∗P < 0.05, ∗∗P < 0.01 vs the TRZ group; ▲P < 0.05, ▲▲P < 0.01 vs the TRZ + OST H group.

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  Fig. 10. Schematic illustration summarizing the protective effects of OST against TRZ-induced cardiotoxicity by enhancing autophagy via regulating the p38MAPK/mTOR signaling pathway.