FIG 4.

Butyrate increases P-gp expression via HDAC inhibition. (A) Significantly enriched pathways (wikipathways) in butyrate-treated T84 cells determined by g:Profiler analysis of RNAseq data (Fig. 1). (B) Fold change expression of Abcb1 by qPCR of T84 cells after 4 h incubation with panobinostat (Pb, 20 μM), butyrate (Buty., 5 mM), or a combination compared to DMSO vehicle (control). Ns P > 0.05; **, P < 0.01; ***, P < 0.005; by one-way ANOVA with Tukey’s multiple-comparison test. (C) Representative Western blot and densitometry of P-gp expression in T84 cells after 24 h incubation with panobinostat or butyrate as in Fig. 3B, ns P > 0.05; *, P < 0.05; **, P < 0.01 by one-way ANOVA with Tukey’s multiple-comparison test. (D) Western blot of histone 3 lysine 27 acetylation mark (H3K27Ac) in T84 cells after 24 h incubation with panobinostat or butyrate as in Fig. 4B, with GAPDH as loading control. (B-D) Representative data of at least two independent experiments.