These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Pioglitazone stimulates apolipoprotein A-I production without affecting HDL removal in HepG2 cells: involvement of PPAR-alpha.
    Author: Qin S, Liu T, Kamanna VS, Kashyap ML.
    Journal: Arterioscler Thromb Vasc Biol; 2007 Nov; 27(11):2428-34. PubMed ID: 17872455.
    Abstract:
    OBJECTIVE: Pioglitazone, an antihyperglycemic drug, increases plasma high-density lipoprotein (HDL)-cholesterol in patients with type 2 diabetes. The mechanisms by which pioglitazone regulate HDL levels are not clear. This study examined the effect of pioglitazone on hepatocyte apolipoprotein AI (apoA-I) and apoA-II production and HDL-protein/cholesterol ester uptake. METHODS AND RESULTS: In human hepatoblastoma (HepG2) cells, pioglitazone, dose-dependently (0.5 to 10 micromol/L), increased the de novo synthesis (up to 45%), secretion (up to 44%), and mRNA expression (up to 59%) of apoA-I. Pioglitazone also increased apoA-II de novo synthesis (up to 73%) and mRNA expression (up to 129%). Pioglitazone did not affect the uptake of HDL3-protein or HDL3-cholesterol ester in HepG2 cells. The pioglitazone-induced apoA-I lipoprotein particles increased cholesterol efflux from THP-1 macrophages. The pioglitazone-induced apoA-I secretion or mRNA expression by the HepG2 cells was abrogated with the suppression of PPAR-alpha by small interfering RNA or a specific inhibitor of PPAR-alpha, MK886. CONCLUSIONS: The data indicate that pioglitazone increases HDL by stimulating the de novo hepatic synthesis of apoA-I without affecting hepatic HDL-protein or HDL-cholesterol removal. We suggest that pioglitazone-mediated hepatic activation of PPAR-alpha may be one of the mechanisms of action of pioglitazone to raise hepatic apoA-I and HDL.
    [Abstract] [Full Text] [Related] [New Search]