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Medium-chain fatty acid enriched-diacylglycerol (MCE-DAG) accelerated cholesterol uptake and synthesis without impact on intracellular cholesterol level in HepG2

중쇄지방산 강화 디아실글리세롤(MCE-DAG)이 간세포 내 콜레스테롤 흡수 및 합성 기전에 미치는 영향

  • Received : 2019.05.14
  • Accepted : 2019.05.29
  • Published : 2019.06.30

Abstract

The effects of medium-chain enriched diacylglycerol (MCE-DAG) oil on hepatic cholesterol homeostasis were investigated. HepG2 hepatocytes were treated with either 0.5, 1.0, or $1.5{\mu}g/mL$ of MCE-DAG for 48 h. There was no evidence of cytotoxicity by MCE-DAG up to $1.5{\mu}g/mL$. The level of proteins for cholesterol uptake including CLATHRIN and LDL receptor increased by MCE-DAG in a dose-dependent manner (p<0.05). Furthermore, proprotein convertase subtilisin/kexin type 9, an inhibitor of LDLR, was dose-dependently diminished (p<0.05), indicating cholesterol clearance raised. MCE-DAG significantly increased 3-hydroxy-3-methylglutaryl-coenzyme A reductase and acetyl-CoA acetyltransferase2 (p<0.05), required for cholesterol synthesis, and their transcriptional regulator sterol regulatory element-binding protein2 (p<0.05). These findings suggest that given conditions of prolonged sterol fasting in the current study activated both hepatic cholesterol synthesis and clearance by MCE-DAG. However, total intracellular level of cholesterol was not altered by MCE-DAG. Taken together, MCE-DAG has the potential to prevent hypercholesterolemia by increasing hepatic cholesterol uptake without affecting intracellular cholesterol level.

Keywords

cholesterol clearance;cholesterol homeostasis;cholesterol synthesis;medium-chain fatty acid enriched-diacylglycerol;structured lipid

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Fig. 1 Effects of MCE-DAG on hepatic cholesterol uptake in HepG2 cells. Data expressed as the mean±standard error.

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Fig. 2 Effects of MCE-DAG on hepatic cholesterol synthesis in hepatocytes.

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Fig. 3 Effects of MCE-DAG on the regulators for hepatic cholesterol homeostasis.

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Fig. 4 Intracellular total cholesterol contents on MCE-DAG.

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