Inhibition of miR-128-3p Attenuated Doxorubicin-Triggered Acute Cardiac Injury in Mice by the Regulation of PPAR-γ

Figure 1. DOX decreased miR-128-3p expression. (a, b) The level of miR-128-3p expression in DOX-treated cells (n = 6 for each points). (c, d) The level of miR-128-3p expression in DOX-treated hearts (n = 6 for each points). Data are expressed as mean ± SEM. ∗P < 0.05 vs. NS or PBS group.

Figure 2. miR-128-3p inhibition attenuated cardiac injury in DOX-treated mice. (a) The level of miR-128-3p expression in the hearts (n = 6). (b) Body weight (n = 12). (c) The ratio of body weight to tibial length (n = 12). (d) The ratio of heart weight to tibial length (n = 12). (e) The mRNA level of BNP in the hearts (n = 6). (f, g) The plasma levels of cTnI and NT-proBNP (n = 6). Data are expressed as mean ± SEM. ∗P < 0.05 vs. NS/control group; #P < 0.05 vs. DOX/control group.

Figure 3. miR-128-3p inhibition improved cardiac function in DOX-treated mice. (a) Heart rate in the indicated groups (n = 8). (b) Ejection fraction in the indicated groups (n = 8). (c, d) ±dP/dt in the mice (n = 8). (e) LVEDP in the indicated groups (n = 8). Data are expressed as mean ± SEM. ∗P < 0.05 vs. NS/control group; #P < 0.05 vs. DOX/control group.

Figure 4. miR-128-3p inhibition attenuated oxidative damage in DOX-treated mice. (a–c) The activities of SOD, catalase, and Gpx in the mice (n = 6). (d) The levels of GSH in mice (n = 6). (e–g) The levels of MDA, 4-HNE, and 3-NT in the indicated groups (n = 6). Data are expressed as mean ± SEM. ∗P < 0.05 vs. NS/control group; #P < 0.05 vs. DOX/control group.

Figure 5. miR-128-3p inhibition attenuated inflammatory response in mice. (a) p65-DNA binding activity (n = 6). (b, c) The levels of inflammatory factors in mice (n = 6). (d–f) Western blot of Bax and nuclear p65 (n = 6). (g) The caspase 3 activity (n = 6). (h) TUNEL staining (n = 6). Data are expressed as mean ± SEM. ∗P < 0.05 vs. NS/control group; #P < 0.05 vs. DOX/control group.

Figure 6. miR-128-3p targeted PPAR-γ in cardiomyocytes. (a) Binding site with miR-128-3p in 3′-UTR of PPAR-γ. (b) The luciferase assay (n = 6). (c–f) The expression of miR-128-3p and PPAR-γ (n = 6). (g, h) The protein expression of PPAR-γ (n = 6). (i) p65-DNA binding activity (n = 6). (j) TNF-α mRNA level (n = 6). (k) ROS production in the cells (n = 6). (l) Cell viability (n = 6). (m) Western blot of Bax (n = 6). Data are expressed as mean ± SEM. ∗P < 0.05 vs. matched control.

Figure 7. GW9662 abolished protective effects in mice provided by miR-128-3p inhibition. (a) The protein expression of PPAR-γ (n = 6). (b) Ejection fraction (n = 12). (c) TNF-α mRNA level (n = 6). (d) 4-HNE level (n = 8). (e) Caspase3 activity (n = 8). (f) Western blot of Bax (n = 6). Data are expressed as mean ± SEM. ∗P < 0.05 vs. matched control.