| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Departments of Medicine and Physiology, Division of Endocrinology and Metabolism (G.F.L., K.U., N.L., L.S.), and Department of Laboratory Medicine and Pathobiology (M.N., K.A.), Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada M5G 1X8
Address all correspondence and requests for reprints to: Dr. Gary F. Lewis, Toronto General Hospital, 200 Elizabeth Street, EN11-229, Toronto, Ontario, Canada M5G 2C4. E-mail: gary.lewis{at}uhn.on.ca.
It is not known whether intestinal lipoprotein production is stimulated by an acute elevation of plasma free fatty acids (FFA). We examined the effect of an intralipid and heparin infusion on the intestinal lipoprotein production rate (PR) in insulin-sensitive [chow-fed (CHOW)], insulin-resistant [60% fructose (FRUC) or 60% fat-fed (FAT)], and insulin-sensitized [FRUC or FAT plus rosiglitazone (RSG)-treated] Syrian Golden hamsters. After 5 wk of treatment, overnight-fasted hamsters underwent in vivo Triton WR-1339 studies for measurement of apolipoprotein B48 (apoB48) PR in large (Svedberg unit, >400) and small (Svedberg unit, 100400) lipoprotein fractions, with an antecedent 90-min infusion of 20% intralipid and heparin (IH) to raise plasma FFA levels approximately 5- to 8-fold vs. those in the saline control study. IH markedly increased apoB48 PR in CHOW by 3- to 5-fold, which was confirmed ex vivo in pulse-chase experiments in primary cultured hamster enterocytes. Oleate, but not glycerol, infusion was associated with a similar elevation of apoB48 PR as IH. In FRUC and FAT, basal (saline control) apoB48 PR was approximately 4-fold greater than that in CHOW; there was no additional stimulation with IH in vivo and only minimal additional stimulation ex vivo. RSG partially normalized basal apoB48 PR in FAT and FRUC, and PR was markedly stimulated with IH. We conclude that intestinal lipoprotein production is markedly stimulated by an acute elevation of plasma FFAs in insulin-sensitive hamsters, in which basal production is low, but minimally in insulin-resistant hamsters, in which basal production is already elevated. With RSG treatment, basal PR is partially normalized, and they become more susceptible to the acute FFA stimulatory effect.
This article has been cited by other articles:
![]() |
I. J. Goldberg, Y. Hu, H.-L. Noh, J. Wei, L. A. Huggins, M. G. Rackmill, H. Hamai, B. N. Reid, W. S. Blaner, and L.-S. Huang Decreased Lipoprotein Clearance Is Responsible for Increased Cholesterol in LDL Receptor Knockout Mice With Streptozotocin-Induced Diabetes Diabetes, June 1, 2008; 57(6): 1674 - 1682. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Duez, B. Lamarche, R. Valero, M. Pavlic, S. Proctor, C. Xiao, L. Szeto, B. W. Patterson, and G. F. Lewis Both Intestinal and Hepatic Lipoprotein Production Are Stimulated by an Acute Elevation of Plasma Free Fatty Acids in Humans Circulation, May 6, 2008; 117(18): 2369 - 2376. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-C. Hogue, B. Lamarche, A. J. Tremblay, J. Bergeron, C. Gagne, and P. Couture Evidence of increased secretion of apolipoprotein B-48-containing lipoproteins in subjects with type 2 diabetes J. Lipid Res., June 1, 2007; 48(6): 1336 - 1342. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Qin, W. Qiu, R. K. Avramoglu, and K. Adeli Tumor Necrosis Factor-{alpha} Induces Intestinal Insulin Resistance and Stimulates the Overproduction of Intestinal Apolipoprotein B48-Containing Lipoproteins Diabetes, February 1, 2007; 56(2): 450 - 461. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Duez, B. Lamarche, K. D. Uffelman, R. Valero, J. S. Cohn, and G. F. Lewis Hyperinsulinemia Is Associated With Increased Production Rate of Intestinal Apolipoprotein B-48-Containing Lipoproteins in Humans Arterioscler. Thromb. Vasc. Biol., June 1, 2006; 26(6): 1357 - 1363. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Endocrinology | Endocrine Reviews | J. Clin. End. & Metab. |
| Molecular Endocrinology | Recent Prog. Horm. Res. | All Endocrine Journals |