Fig. 6. The alteration of lipid catabolism and mitochondrial function in Ahr HKO and of mitochondrial respiration by hepatic ablation of either AhR or PPP2R2D.

a Representative H&E (left) or oil red O (right) staining in the liver of mice fed with Lieber-DeCarli diets for 5 weeks (n = 5 each). Scale bar: 100 μm. b Hepatic (upper) or serum (lower) TG contents in the same mice as in (a) (n = 5 each). c sPLS-DA score plot based on the lipidomics data using mice fed as in (a) (n = 7, 9, 10 mice). d Heatmap and hierarchical correlation analyses using the same data as in (c) (n = 7, 9, 10 mice; FDR <0.01; darker blue, stronger downregulation; darker red, stronger upregulation). e Bar graphs based on Gene Ontology analysis using the same data as in Fig. 4a (n = 3 each). NES and FDR are presented as bar graphs (NES >1.75, FDR <0.25). The pathways associated with mitochondrial function were highlighted in red. f Quantification of mtDNA content. The copy number ratio of mitochondrial/nuclear DNA was assessed by qRT-PCR assays for mt-COXI and nRIP140 using total DNA samples isolated from the same mice as in (a) (n = 5 each). g qRT-PCR assays for transcripts associated with mitochondrial function in mPHs isolated from WT or Ahr HKO mice (n = 3 each). h–k OCRs in mPHs. The OCRs of basal, ATP production (via oligomycin addition), maximal (with FCCP), and non-mitochondrial respiration (with rotenone + antimycin A [Rot + AA]) were determined using an XFp Extracellular Flux Analyzer. Real-time triplicate readings (left) and calculated mitochondrial respiration rates (right) are shown (n = 3 each). mPHs were treated with control (upper) or 100 mM ethanol (lower) for 24 h (h); mPHs were treated with 10 μM CQ for 24 h (i); the mPHs were either untreated (control) (upper) or treated with 100 mM ethanol (lower) for 24 h after transfection with siPPP2R2D (or siCon) for 24 h (j); and mPHs were transfected with PPP2R2D plasmids for 24 h (k). The OCRs were normalized to the cell counts. Values are expressed as means ± SEM. Significantly different compared to Con or WT. Data were analyzed via one-way ANOVA with Tukey HSD (b, k), one-way ANOVA with LSD (f, i), or two-tailed Student’s t-test (g, h, j). Source data are provided as a Source Data file.