Lipidomic Analysis of the Effects of 20(R)-Protopanaxadiol on Lipid Accumulation in HepG2 Cells

Objective: This study aimed to investigate the intervention effects of 20(R)-Protopanaxadiol (20(R)-PPD) and characterize the dynamic changes in lipid metabolism in HepG2 cells with lipid metabolism disorders. The analysis was performed using a free fatty acid (FFA)-induced HepG2 hepatocyte steatosis model combined with ultra-performance liquid chromatography–quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS)-based untargeted lipidomics. Methods: HepG2 hepatocyte steatosis model was induced by FFA. Interventions were performed with 20(R)-PPD at different concentrations. Changes in intracellular metabolites were detected by UPLC-QTOF-MS/MS technology. Differential metabolites were screened through multivariate statistical analysis, and key metabolic pathways were analyzed. Results: Compared with the model control group, lipid accumulation in the HepG2 hepatocyte steatosis model was significantly ameliorated by 20(R)-PPD (p < 0.01), and the intracellular levels of total cholesterol (TC) and triglycerides (TGs) were significantly reduced (p < 0.01). Sixty-nine overlapping differential metabolites, mainly glycerophospholipids, were putatively annotated across all four pairwise comparisons via untargeted lipidomics analysis. Further analysis of the aforementioned metabolites revealed that 20(R)-PPD may modulate lipid metabolic processes in HepG2 cells through metabolic pathways including glycerophospholipid metabolism. Conclusions: Treatment with 20(R)-PPD reduced intracellular lipid, TC and TG levels in FFA-exposed HepG2 cells and induced changes in putatively annotated lipid profiles. These observations in an in vitro cell model suggest potential lipid-modulating properties of 20(R)-PPD at the hepatocyte level and support further investigation of this compound for lipid-related hepatic disorders.