Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
J Biol Chem. 2004 Apr 30;279(18):19362-74. Epub 2004 Feb 17.

Regulation of hepatic apolipoprotein B-lipoprotein assembly and secretion by the availability of fatty acids. I. Differential response to the delivery of fatty acids via albumin or remnant-like emulsion particles.

Author information

  • 1Department of Medicine, Columbia University College of Physicians and Surgeons, New York, New York 10032, USA.

Abstract

The in vivo effects of increased delivery of fatty acids (FA) to the liver are poorly defined. Therefore, we compared the effects of infusing either 6 mM oleic acid (OA) bound to albumin, 0.5-20% Intralipid, or saline for 3 or 6 h into male C57BL/6J mice. Infusions were followed by studies of triglyceride (TG) and apoB secretion. Although plasma FA levels increased similarly after either 20% Intralipid or 6 mM OA, TG secretion increased only after infusion of 4-20% Intralipid; TG secretion was unchanged by 6 mM OA. By contrast, 6-h infusions of either 6 mM OA or 4-20% Intralipid increased apoB secretion. 6 mM OA and 20% Intralipid each increased secretion of apoB from primary hepatocytes ex vivo. Importantly, 0.5-2% Intralipid, which delivered more FA to the liver than 6 mM OA, did not stimulate apoB secretion. Hepatic apoB mRNA levels were unaffected by either 6 mM OA or 20% Intralipid, but microsomal triglyceride transfer protein mRNA was significantly lower after 6-h infusions with 6 mM OA versus either saline or 20% Intralipid. Lower microsomal triglyceride transfer protein mRNA levels were associated with reduced hepatic TG mass after 6-h infusions of 6 mM OA. We conclude that 1) increased FA delivery to the liver in vivo increases secretion of apoB-lipoproteins via post-transcriptional mechanisms, 2) OA-induced apoB-lipoprotein secretion occurred at least in part via mechanisms other than by providing substrate for TG synthesis, and 3) the route of delivery of FA is important for its effects on apoB secretion.

PMID:
14970200
[PubMed - indexed for MEDLINE]
Free full text

LinkOut - more resources

Full Text Sources

Other Literature Sources

PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk