Fig. 3: FFA-induced hepatic lipid accumulation depended on ApoJ.

The cellular contents of TC and TG were quantified in Huh7 cells treated with PA (a) or OA (b) for 24 h (n ≧ 5), CE/FC ratio of PA and OA treated cells (c) (n ≧ 6), and ApoJ expression in Huh7 cells treated with PA (d) or OA (e). The lower panel: ApoJ intensities (n = 3); psApoJ, ApoJ precursor. f Representative images of LDs stained with BODIPY493/503, and g quantification of lipid contents in Huh7.5 cells bearing Luc or ApoJ shRNA treated with PA or OA for 24 h. Scale bar, 100 μm in f. h Quantification of lipid contents in the cells transfected with ApoJ expressing plasmid or control vector. All results are normalized to the respective untreated control and presented as the mean ± SEM (n ≧ 5), and asterisks indicate statistical significance (p < 0.05). Representative IFA images of SOAT2 (red) and Golgi (TGN38, green) (i); SOAT2 and ApoJ (green) (j) in PA- or OA-treated cells were analysed by Coloc2 plugin and FVW31S software as in Fig. 2d. Scale bar, 5 μm. Asterisks indicate statistical significance (p < 0.05). k The PA- (200 μM) or OA- (800 μM) treated Huh7 cells were fed with NBD-Chol, and the SOAT activity was evaluated and expressed as the mean ± SEM (n = 6). l The protein level of SOAT2 in Huh7 cells treated with PA or OA for 24 h. The lower panel: SOAT2 intensities (n ≧ 2). m Huh7 cells were treated with 800 μM OA for 24 h. The cell lysate was immunoprecipitated with antibody against ApoJ and examined by western blot analysis recognizing SOAT1, SOAT2, and ApoJ.