Epigenetic Modulation by Apabetalone Counters Cytokine-Driven Acute Phase Response In Vitro, in Mice and in Patients with Cardiovascular Disease

Figure 3

BET proteins contribute to cytokine-mediated induction of the CRP gene. CRP gene expression changes in HepaRG™ cells (a) and human primary hepatocytes (b) measured by rtPCR in response to IL-6, IL-1β, or combined (dual) cytokine treatment (2 h). Apabetalone pretreatment (1 h, 25 μM) counters mRNA induction in response to single or dual cytokine treatment. Gene expression is graphed relative to DMSO-treated cells. Representative data from three independent repeats is shown. Data is presented as a (c) MZ-1 degrades BRD2, BRD3, and BRD4 protein in HepaRG™ cells in a dose-dependent manner. Representative Western blot data is shown. (d) Quantification of BRD2, BRD3, and BRD4 protein bands relative to β-actin. Data is presented as the mean of four independent (e) BET degradation by MZ-1 significantly repressed dual cytokine-induced CRP transcription. Representative data from three independent repeats is shown. Data is presented as the (f, g) Dual cytokine stimulation (2 h) increases BRD2 (f) and BRD4 (g) occupancy on the CRP transcription start site (CRP TSS) but not in a BET protein-lacking region (desert) as determined by ChIP. Pretreatment (1 h) with apabetalone (25 μM) or JQ1 (0.5 μM) reduces BRD4 association with the CRP promoter (g). Samples were processed in triplicate. Data is presented as the Statistical significance was determined through 1-way ANOVA followed by Tukey’s multiple comparison test, where , , , and ns means no significant difference.

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