title: Lignophenols decrease oleate-induced apolipoprotein-B secretion in HepG2 cells.
abstract: Lignin is one of the components in the plant cell wall, after cellulose, making up 20-30% of the global plant biomass. Lignophenols (LPs) are derivatives of lignin with high phenolic function and antioxidant properties. However, their medicinal property is not well characterised. Apolipoprotein-B (apo-B) is an essential component in very low-density lipoprotein, and high levels of serum apolipoprotein-B (apo-B) are a major factor for coronary heart disease. In this study, we examined the effect of lignophenols on apo-B secretion in HepG2 cells. HepG2 cells were treated with varying concentrations of LPs and 0.8 mm sodium oleate. LPs decreased oleate-induced apo-B secretion in a dose-dependent manner. LPs also decreased oleate-induced microsomal triglyceride transfer protein (MTTP) mRNA expression and cellular total cholesterol, suggesting that lipid bioavailability and lipidation of lipoprotein are likely involved in the decreased secretion of apo-B. Furthermore, LPs decreased oleate-induced mature sterol regulatory element binding protein 2 (SREBP-2), a transcription factor that activates cholesterol biosynthesis. This is the first study to show that LPs can decrease oleate-induced apo-B secretion in HepG2 cells. The modulations of MTTP mRNA expression, cellular total cholesterol metabolism and mature SREBP-2 expression may be important factors in the regulation of apo-B secretion by LPs.
authors.affiliation: Department of Nutrition, Faculty of Health Science, Aomori University of Health and Welfare, Aomori, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Norikura
authors.forename: Yuuka
authors.initials: Y
authors.lastname: Mukai
authors.forename: Shuzo
authors.initials: S
authors.lastname: Fujita
authors.forename: Keigo
authors.initials: K
authors.lastname: Mikame
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Funaoka
authors.forename: Shin
authors.initials: S
authors.lastname: Sato
mesh_terms: D001055:Apolipoproteins B / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D056945:Hep G2 Cells; D006801:Humans; D008031:Lignin / Q000494:pharmacology*; D019301:Oleic Acid / Q000494:pharmacology*; D010636:Phenols / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D051782:Sterol Regulatory Element Binding Protein 2 / Q000235:genetics / Q000378:metabolism
chemical_list: D001055:Apolipoproteins B; D002352:Carrier Proteins; D010636:Phenols; D012333:RNA, Messenger; D051782:Sterol Regulatory Element Binding Protein 2; C106092:microsomal triglyceride transfer protein; D019301:Oleic Acid; C013173:osteum; D008031:Lignin; D002784:Cholesterol