Fig. 5: JQ-1 protects cardiomyocytes from ferroptosis by promoting SIRT1 expression.

A Volcano map of differentially expressed genes in the cardiac tissue from MI with JQ-1 administration and MI in GSE96566. Green dots [Log₂(Fold change) <–0.5 and Log₁₀(pvalue) >2] indicate downregulated genes, red dots [Log₂(Fold change) >0.5 and Log₁₀(pvalue) > 2] indicate upregulated genes, gray dots indicate no significant change genes. B Effect of JQ-1 treatment on Sirt1 mRNA levels in the cardiac tissue from mice 1 day after MI (n = 6). C Effect of EX527 on the cell viability in H9C2 cardiomyocytes with JQ-1 treatment under the erastin challenge (n = 6). D Representative fluorescence images of DCFH-DA staining in H9C2 cardiomyocytes treated with JQ-1 combined with EX527 under the erastin challenge. Scale bars, 100 µm. E Quantitative analysis of ROS levels in (D) (n = 3). F Representative lipid peroxidation images in H9C2 cardiomyocytes treated with JQ-1 combined with EX527 under the erastin challenge. Red: unoxidized C11-BODIPY; Green: oxidized C11-BODIPY; Blue: Hoechst-stained nucleus. Scale bars, 50 μm. G Quantitative analysis of lipid peroxidation levels in (F) (n = 6). Western blot detection (H) and quantification (I) of p-Nrf2 and Nrf2 levels in JQ-1-treated H9C2 cardiomyocytes under the erastin challenge (n = 4). Western blot detection (J) and quantification (K) of GPX4 levels in JQ-1 and/or ML385 treated H9C2 cardiomyocytes under the erastin challenge (n = 4). The data are presented as mean ± SEM. The statistical significance of the data was evaluated using one-way ANOVA with Tukey’s post-hoc test (C, E, and G), and two-way ANOVA followed by Tukey’s test for multiple comparisons (B, I, and K). *P < 0.05; **P < 0.01.