Coptisine promots hepatocyte autophagy and cholesterol efflux to improve lipid accumulation in fatty liver

ObjectiveTo construct a model of fatty liver cell of HepG2 cells treated with oleic acid and palmitic acid, and observe the effects of coptisine(COP) on the accumulation of lipid droplets in fatty liver cells and its mechanism of action.

MethodsThe fatty liver cell model of HepG2 cells was constructed by induction of 100 μmol/L oleic acid and 50 μmol/L palmitic acid.The CCK8 was used to detect the effects of COP at different concentrations on cell proliferation.The cells were divided into the control group, the fatty liver cell model group(FFA group), COP+HepG2 group and COP+FFA group.The RT-PCR and Western blotting were used to detect the mRNA and protein levels of autophagy genes LC3Ⅰ/Ⅱ, ATG5 and cholesterol outflow-mediated factor ABCA1 in four groups.The changes of lipid droplets in contral, FFA and COP+FFA groups were observed using oil red O staining.

ResultsThe results of oil red O staining showed that compared with contral group, the lipid droplets in HepG2 cells treated with palmitic acid and oleic acid increased significantly in FFA group, and the lipid droplets decreased significantly in COP+FFA group.The results of CCK8 showed that the activity of HepG2 cells was not affected by 0-25 μmol/L COP(P>0.05).The results of Western blotting and RT-PCR showed that compared with the control group, the levels of autophagy and cholesterol outflow-mediated factor ABCA1 in the FFA group significantly reduced, while the expression levels of autophagy genes LC3Ⅰ/Ⅱ, ATG5 and ABCA1 in the COP+HepG2 group significantly increased(P < 0.05 to P < 0.01).Compared with the FFA group, the lipid accumulation in COP+FFA group significantly reduced, and the difference of which between FFA group and COP+FFA group was statistically significnat(P < 0.05 to P < 0.01).The autophagy and cholesterol efflux disorders were also improved in the COP+FFA group.

ConclusionsCOP can promote the autophagy and cholesterol efflux of HepG2 cells, and alleviate the accumulation of lipids in fatty liver cells induced by oleic acid and palmitic acid.