为了探究DHA脂质体对脂代谢的调节作用。首先利用游离脂肪酸诱导HepG2细胞，DHA脂质体干预后检测甘油三酯（TG），胆固醇（TC）含量，RT-PCR检测脂肪酸合成酶（FAS），固醇调节元件结合蛋白1（SREBP-1）的mRNA表达。其次将雄性C57BL/6J小鼠（6周龄）随机分为对照组（C）、模型组（M）、DHA脂乳剂组（O-DHA）、DHA脂质体组（L-DHA）。12周后，检测脂肪酸合成酶（FAS），肉碱棕榈酰转移酶1（CPT-1）蛋白表达量以及脂肪酸合成酶（FAS），苹果酸酶（ME），肉碱棕榈酰转移酶1（CPT-1），脂蛋白酯酶（LPL）的酶活力。结果表明DHA脂质体可显著降低HepG2细胞的TC，TG含量（p<0.05），分别降低了62.91%和48.73%，且显著降低了FAS（48.62%），SREBP-1（38.53%）的mRNA相对表达量（p<0.05）。动物实验结果表明DHA脂质体显著降低了高脂饮食小鼠附睾脂肪含量（14.26%）(p<0.05），且显著降低了高脂饮食小鼠FAS（74.29%）蛋白表达量（p<0.05），显著升高了CPT-1（约1.70倍）的蛋白表达量（p<0.05）。DHA脂质体还可显著抑制FAS，ME酶活力（p<0.05），分别降低了30.33%和11.79%。显著促进了CPT-1，LPL酶活力（p<0.05），分别升高了10.08%和15.12%。本研究表明DHA脂质体可改善高脂饮食诱导的脂代谢紊乱，为深海鱼油的开发利用提供理论依据。

To explore the effects of DHA liposomes on lipid metabolism, HepG2 cells were induced by free fatty acids. After the intervention of DHA liposomes, the contents of TG and TC were detected. The mRNA expression of Fatty acid synthase (FAS) and Sterol regulatory element binding protein 1 (SREBP-1) were detected by RT-PCR. Then male C57BL/6J mice (6 weeks old) were housed and randomly devided into control group (C), model group (M), TG-DHA emulsion (O-DHA), TG-DHA liposome (L-DHA). After 12 weeks, the protein expression levels of FAS, CPT-1 were determined by immunohistochemistry, the enzyme activity of Fatty acid synthase (FAS), malic enzyme (ME), carnitine palmitoyltransferase 1 (CPT-1), lipoprotein esterase (LPL) were detected using ELISA. The results showed that DHA liposomes significantly reduced the TC and TG contents (p<0.05) by 62.91% and 48.73% respectively; significantly reduced the mRNA expression levels of FAS (48.62%) and SREBP-1 (38.53%) (p<0.05). The results of animal experiments showed that DHA liposomes significantly reduced theepididymal fat content (14.26%) of high-fat diet mice (p<0.05); significantly reduced the protein expression levels of FAS (74.29%) (p< 0.05) and increased the protein expression levels of CPT-1 (1.70 folds) (p<0.05). DHA liposomes could significantly inhibited the activities of FAS, ME (p<0.05), reduced by 30.33% and 11.79% respectively; and promoted the activities of CPT-1, LPL (p<0.05), increased by 10.08% and 15.12% respectively. This study showed that DHA liposomes can improve lipid metabolism disorder induced by high-fat diet, and provide theoretical basis for the development and utilization of deep-sea fish oil.

国家重点研发计划项目（2018YFC0311201；2019YFC1604605）；山东省重点研发计划项目（2019GHY112058）