Oxidized Low-Density Lipoproteins Trigger Hepatocellular Oxidative Stress with the Formation of Cholesteryl Ester Hydroperoxide-Enriched Lipid Droplets

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are linked to dyslipidemia and oxidative stress, with oxidized low-density lipoproteins (oxLDL) considered a risk factor. This study aimed to clarify the role of oxLDL versus native LDL (nLDL) in hepatocellular lipid droplet formation and oxidative stress. Methods: The researchers used a human liver-derived C3A cell line. They prepared nLDL and oxLDL (oxidized for 2, 8, or 24 hours) and analyzed lipid profiles using LC-MS/MS. Cells were stimulated with LDL (200 ng protein/10^4^ cells) for 24 hours. Lipid droplets were visualized via fluorescence microscopy, and gene expression related to lipid metabolism was measured by real-time PCR. Key Results: nLDL increased cholesteryl ester (CE) accumulation and promoted triglyceride hydrolysis, associated with altered expression of genes like LIPE and ATGL. In contrast, oxLDL (2 h) led to a striking increase in lipid droplets enriched with CE hydroperoxides (CE-OOH) and increased the oxidative stress index PC-OOH/PC. Gene expression changes in oxLDL-treated cells included altered SREBP1, FASN, and DGAT1. Limitations: The study is an in vitro experiment using a single cell line, making it difficult to determine if the model directly represents NAFLD or NASH. Implications: The results suggest that oxLDL-induced CE-OOH-enriched lipid droplets and oxidative stress may play a crucial role in NAFLD/NASH pathogenesis, proposing oxLDL as a potential therapeutic target and biomarker. Further in vivo and human studies are needed.