Fish oil and chicoric acid combination protects better against palmitate-induced lipid accumulation via regulating AMPK-mediated SREBP-1/FAS and PPARα/UCP2 pathways

Non-alcoholic fatty liver disease (NAFLD) is associated with lipid accumulation and lipotoxicity. The main aim of this study is to evaluate the synergistic treatment effect of fish oils (FOs) and chicoric acid (CA) in palmitate (PA)-induced NAFLD HepG2 model. HepG2 cells were pre-treated with palmitate (0.75 mM) for 24 h, and then were exposed to CA, FOs and combination of these chemicals for another 24 h. Gene expression and protein levels were determined using qRT-PCR and western blotting or ELISA analysing, respectively. The combination index (CI) values of FOs and CA in HepG2 cells were calculated according to the Chou-Talalay equation using the CompuSyn software. FOs and CA acid together synergistically reduced lipid accumulation as indicated by decreased oil red O staining (vehicle-treated control: 1 ± 0.1; PA-treated control: 4.7 ± 0.4; PA + CA100: 3.9 ± 0.4; PA + CA200: 2.4 ± 0.3; PA + FOs: 2.7 ± 0.1; PA + CA200 + FOs: 1.5 ± 0.1) and triglyceride (vehicle-treatedcontrol:10 ± 1.2; PA-treated control: 25.8 ± 2.7; PA + CA100: 18.9 ± 2.5; PA + CA200: 14.4 ± 1.8; PA + FOs: 15.2 ± 2.4; PA + CA200 + FOs: 11.9 ± 1.5) levels in PA-treated HepG2 cells. Gene expression and Immunoblotting analysis confirmed the combination effect of FOs and CA in up-regulation of AMPK-mediated PPARα/UCP2 and down-regulation of AMPK-mediated SREBP-1/FAS signalling pathways. Collectively, these results suggest that combining FOs with CA can serve as a potential combination therapy for NAFLD.