fig4

Figure 4. HepG2 cells co-cultured with Caco-2 exposed to FFAs and LPS accumulated intracellular lipid droplets. Fat accumulation in HepG2 on bottom of the co-culture system was evaluated by ORO staining (200× magnification) and quantified by ImageJ software in 10 random non-overlapping micrographs for each experimental condition by calculating the percentage of pixels above the threshold value with respect to the total number of pixels per area. At least three independent experiments were conducted (A, B). Intracellular TG content was assessed in lysates from HepG2 cells (C). (D, E) SREBP1c and FASn (genes involved in de novo lipogenesis); (F) PPARα (marker of β-oxidation); (G) and MTTP expressions were evaluated by qRT-PCR in HepG2 cell lysates; mRNA levels were normalized to β-actin. Data are expressed as fold increase compared to Ctrl. For violin plots, data are expressed as median concentration (thick dashed lines) and interquartile range (dotted lines). At least three independent experiments were conducted and pooled together. ***P < 0.0001 according to one-way ANOVA. FFAs: Free fatty acids; LPS: lipopolysaccharides; ORO: oil red O; SREBP1c: sterol regulatory element binding protein 1-c; FASn: fatty acid synthase; PPARα: peroxisome proliferator-activated receptor alpha; MTTP: microsomal triglyceride transfer protein; ANOVA: one-way analysis of variance.