In the present study, effects of cis-9,10-epoxystearic acid (ESA) generated by the thermal oxidation of oleic acid on HepG2 cells, including intracellular lipid accumulation, fatty acid composition, and lipid metabolism, were investigated. Our results revealed that ESA increased the number and size of cellular lipid droplets. Intracellular triacylglycerol and total cholesterol content demonstrated that ESA induced lipid accumulation in HepG2 cells in a dose- and time-dependent manner. Results of fatty acid composition further indicated that ESA could lead to intracellular lipid accumulation. Our results also revealed that ESA may suppress the fatty acid oxidation in peroxisomes and mitochondria, including PPARα, Cpt1α, and Acox1, whereas the expression of genes involved in lipid synthesis, including Srebp-1c and Scd1, was enhanced. These findings provide critical information on the effects of ESA on HepG2 cells, particularly lipid accumulation and metabolism, which is important for evaluating the biosafety of the oxidative product of oleic acid. PRACTICAL APPLICATION: The administration of cis-9,10-epoxystearic acid to HepG2 cells could lead to disorder of lipid metabolism of cells by enhancing the intracellular lipid content, as well as suppressing the fatty acid oxidation in peroxisomes and mitochondria. These findings could provide information for the evaluation of the biosafety of the oxidative product of oleic acid.

中文翻译：

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环氧硬脂酸对HepG2细胞脂质代谢的影响

在本研究中，研究了油酸热氧化产生的顺式 9,10-环氧硬脂酸 (ESA) 对 HepG2 细胞的影响，包括细胞内脂质积累、脂肪酸组成和脂质代谢。我们的结果表明，ESA 增加了细胞脂滴的数量和大小。细胞内甘油三酯和总胆固醇含量表明 ESA 以剂量和时间依赖性方式诱导 HepG2 细胞中的脂质积累。脂肪酸组成的结果进一步表明ESA可能导致细胞内脂质积累。我们的研究结果还表明，ESA 可能抑制过氧化物酶体和线粒体（包括 PPARα、Cpt1α 和 Acox1）中的脂肪酸氧化，而参与脂质合成的基因（包括 Srebp-1c 和 Scd1）的表达得到增强。这些发现提供了关于 ESA 对 HepG2 细胞影响的关键信息，特别是脂质积累和代谢，这对于评估油酸氧化产物的生物安全性很重要。实际应用：顺式9,10-环氧硬脂酸给予HepG2细胞可通过增加细胞内脂质含量以及抑制过氧化物酶体和线粒体中的脂肪酸氧化，导致细胞脂质代谢紊乱。这些发现可为评价油酸氧化产物的生物安全性提供信息。10-环氧硬脂酸对HepG2细胞可通过增加细胞内脂质含量以及抑制过氧化物酶体和线粒体中的脂肪酸氧化而导致细胞脂质代谢紊乱。这些发现可为评价油酸氧化产物的生物安全性提供信息。10-环氧硬脂酸对HepG2细胞可通过增加细胞内脂质含量以及抑制过氧化物酶体和线粒体中的脂肪酸氧化而导致细胞脂质代谢紊乱。这些发现可为评价油酸氧化产物的生物安全性提供信息。