Figure 2: Acetate predominately activates lipid synthesis pathway through epigenetic regulation under hypoxia.
From: Acetate functions as an epigenetic metabolite to promote lipid synthesis under hypoxia
(a) Scatter plot of mRNA expression data of 139 metabolic genes in HepG2 cells, comparing cells treated with hypoxia (y axis) to normoxia (x axis). The mRNA expression value of triplicate experiments was shown on a log 2 scale. Grey lines indicated two-fold differences in the mRNA expression levels between two groups. Upregulated genes (>2-fold change, P<0.05) were shown in magenta. Downregulated expressed genes (>2-fold change, P<0.05) were shown in blue. Two-tailed unpaired Student’s t-test was used. (b) Scatter plot of mRNA expression data of 139 metabolic genes in HepG2 cells under normoxia, comparing cells treated with 2.5 mM acetate (y axis) to acetate-free (x axis). The mRNA expression value of triplicate experiments was shown on a log2 scale. Grey lines indicated two-fold differences in the mRNA expression levels between two groups. Downregulated genes (>2-fold change, P<0.05) were shown in blue. Two-tailed unpaired Student’s t-test was used. (c) Scatter plot of mRNA expression data of 139 metabolic genes in HepG2 cells under hypoxia, comparing cells treated with 2.5 mM acetate (y axis) with acetate-free (x axis). The mRNA expression value of triplicate experiments was shown on a log 2 scale. Grey lines indicated two-fold differences in the mRNA expression levels between two groups. Upregulated genes (>2-fold change, P< 0.05) were shown in magenta. Two-tailed unpaired Student’s t-test was used. (d) Fold-change analysis of the mRNA expression of 139 genes in HepG2 cells treated with or without 2.5 mM acetate under hypoxia. (e,f) FASN (e) and ACACA (f) mRNA levels in HepG2 cells treated with indicated concentrations of acetate for 12 h under normoxia or hypoxia were quantified by qPCR. The results were presented as mean±s.d. of triplicate experiments. (g,h) ChIP-qPCR assays showing H3K9, H3K27 and H3K56 acetylation enrichment at FASN (g) and ACACA (h) promoter regions in HepG2 cells treated with indicated concentrations of acetate under normoxia or hypoxia for 4 h. Rabbit IgG was included as a negative control. Each histogram was presented as mean±s.d. of triplicate experiments (*P<0.05; **P<0.01; NS, not significant; by two-tailed unpaired Student’s t-test).
