Down-regulation of apolipoprotein M expression is mediated by phosphatidylinositol 3-kinase in HepG2 cells.
Författare
Summary, in English
Apolipoprotein M (apoM) is a novel apolipoprotein present mostly in high-density lipoprotein (HDL) in human plasma. In the present study, we demonstrate that insulin, insulin-like growth factor I (IGF-I), and IGF-I potential peptide (IGF-IPP) significantly inhibits apoM expression, in a dose- and a time-dependent manner, in the human hepatoma cell line, HepG2 cells. Insulin-induced down-regulation of apoM was blocked by AG1024 (a specific insulin receptor inhibitor) and LY294002 (a phosphatidylinositol 3-kinase (PI3K) inhibitor), which indicates that it is mediated via the activation of PI3K pathway. In contrast, PD98059 (a MAP kinase inhibitor) did not influence insulin-induced down-regulation of apoM expression, and activation of neither PPAR-alpha agonist (GW7647) nor PPAR-gamma agonist (GW1929) influences apoM expression in HepG2 cells, which indicates that regulation of apoM expression is not related to the activation of PPAR-alpha and PPAR-gamma in hepatic cells, whereas, both PPAR-Of and PPAR-gamma agonists could inhibit apoB expression. Moreover, in the present study, we demonstrated that PPAR beta/delta agonist (GW501516) could inhibit both apoM and apoB expression in the HepG2 cells. In conclusion, this study shows that apoM expression is regulated by PI3-kinase in HepG2-cells. (c) 2006 Elsevier B.V. All rights reserved.
Publiceringsår
2006
Språk
Engelska
Sidor
256-260
Publikation/Tidskrift/Serie
Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids
Volym
1761
Issue
2
Fulltext
- Available as PDF - 151 kB
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Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
Elsevier
Ämne
- Medicinal Chemistry
- Other Clinical Medicine
- Pharmacology and Toxicology
Nyckelord
- line
- insulin
- PPARs
- apolipoprotein M
- phosphatidylinositol 3-kinase and HepG2 cell
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 1388-1981