Figure 4.

BRD4 is indispensable for LPS-induced peritoneal macrophage senescence in mice. Peritoneal macrophages from wild type mice were treated with BRD4-specific siRNA or the BRD4 inhibitor JQ-1 for 24 h, followed by LPS stimulation for 24 h. (A) Representative SA-β-gal and DAPI counterstaining of peritoneal macrophages from C57BL6 mice and quantitative analysis of positive cells. Scale bar, 50 μm. (B) Cluster heatmaps of SASP transcription levels and scatter plots of representative differentially expressed IL-6 and CXCL1 by qRT-PCR analysis. (C) Western blot analysis and quantification of the expression of the senescence-related markers p53, p21, and p16. (D) Immunofluorescence measurements of BRD4 and p16 examined by confocal microscopy. Scale bar, 50 μm. (E) The lipid accumulation was measured by representative Oil Red O staining. The number of positive results was counted. The data all represent measurement data presented as the mean ± SD. Statistical analysis was performed for the comparison of multiple groups using one-way ANOVA, followed by Tukey’s post-hoc test. The experiment was repeated three times. *p <0.05 vs. LPS; **p <0.01 vs. LPS; ***p <0.001 vs. LPS; ****p <0.0001 vs. LPS.