|
|
||||||||
Correspondence to: Marshall B. Elam, at Division of Clinical Pharmacology, University of Tennessee Health Sciences Center, 874 Union Avenue, Memphis, TN, 38112. e.mail: melam@utmem.edu
The corpulent JCR:LA-cp rat (cp/cp) is a useful model for study of the metabolic consequences of obesity and hyperinsulinemia. To assess the effect of hyperinsulinemia on VLDL secretion in this model, we measured rates of secretion of VLDL in perfused livers derived from cp/cp rats and their lean littermates. Livers of cp/cp rats secreted significantly greater amounts of VLDL triglyceride and apolipoprotein, compared with lean littermates. The content of apoB, apoE, and apoCs in both perfusate and plasma VLDL was greater in the cp/cp rat, as was the apolipoprotein (apo)C, apoA-I, and apoA-IV content of plasma HDL. Triglyceride content was also greater in cp/cp livers, as was hepatic lipogenesis and expression of lipogenic enzymes and sterol regulatory element binding protein-1 (SREBP-1). Hepatic mRNAs for apoE, and apoA-I were higher in livers of cp/cp rats. In contrast, the steady state levels of apoC-II, apoC-III, and apoB mRNAs were unchanged.
Thus, livers of obese hyperinsulinemic cp/cp JCR:LA-cp rats secrete a greater number of VLDL particles that are enriched in triglyceride, apoE, and apoC. Greater secretion of VLDL in the cp/cp rat in part results from higher endogenous fatty acid synthesis, which in turn may occur in response to increased expression of the lipogenic enzyme regulator SREBP-1c. Elam, M. B., H. G. Wilcox, L. M. Cagen, X. Deng, R. Raghow, P. Kumar, M. Heimberg, and J. C. Russell. Increased hepatic VLDL secretion, lipogenesis, and SREBP-1 expression in the corpulent JCR:LA-cp rat. J. Lipid Res. 2001. 42: 20392048.
Supplementary key words: animal, cells cultured, liver, obesity, insulin, apolipoprotein, fatty acid synthase, acetyl-coA carboxylase, transcription factor
This article has been cited by other articles:
![]() |
J. C. Russell, S. D. Proctor, S. E. Kelly, and D. N. Brindley Pair feeding-mediated changes in metabolism: stress response and pathophysiology in insulin-resistant, atherosclerosis-prone JCR:LA-cp rats Am J Physiol Endocrinol Metab, June 1, 2008; 294(6): E1078 - E1087. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. N. Baumgardner, K. Shankar, L. Hennings, T. M. Badger, and M. J. J. Ronis A new model for nonalcoholic steatohepatitis in the rat utilizing total enteral nutrition to overfeed a high-polyunsaturated fat diet Am J Physiol Gastrointest Liver Physiol, January 1, 2008; 294(1): G27 - G38. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Deng, C. Yellaturu, L. Cagen, H. G. Wilcox, E. A. Park, R. Raghow, and M. B. Elam Expression of the Rat Sterol Regulatory Element-binding Protein-1c Gene in Response to Insulin Is Mediated by Increased Transactivating Capacity of Specificity Protein 1 (Sp1) J. Biol. Chem., June 15, 2007; 282(24): 17517 - 17529. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y.-L. Zhang, A. Hernandez-Ono, P. Siri, S. Weisberg, D. Conlon, M. J. Graham, R. M. Crooke, L.-S. Huang, and H. N. Ginsberg Aberrant Hepatic Expression of PPAR{gamma}2 Stimulates Hepatic Lipogenesis in a Mouse Model of Obesity, Insulin Resistance, Dyslipidemia, and Hepatic Steatosis J. Biol. Chem., December 8, 2006; 281(49): 37603 - 37615. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. M. Federico, M. Naples, D. Taylor, and K. Adeli Intestinal Insulin Resistance and Aberrant Production of Apolipoprotein B48 Lipoproteins in an Animal Model of Insulin Resistance and Metabolic Dyslipidemia: Evidence for Activation of Protein Tyrosine Phosphatase-1B, Extracellular Signal-Related Kinase, and Sterol Regulatory Element-Binding Protein-1c in the Fructose-Fed Hamster Intestine. Diabetes, May 1, 2006; 55(5): 1316 - 1326. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Myerson, C. Ngai, J. Jones, S. Holleran, R. Ramakrishnan, L. Berglund, and H. N. Ginsberg Treatment with high-dose simvastatin reduces secretion of apolipoprotein B-lipoproteins in patients with diabetic dyslipidemia J. Lipid Res., December 1, 2005; 46(12): 2735 - 2744. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Deng, M. B. Elam, H. G. Wilcox, L. M. Cagen, E. A. Park, R. Raghow, D. Patel, P. Kumar, A. Sheybani, and J. C. Russell Dietary Olive Oil and Menhaden Oil Mitigate Induction of Lipogenesis in Hyperinsulinemic Corpulent JCR:LA-cp Rats: Microarray Analysis of Lipid-Related Gene Expression Endocrinology, December 1, 2004; 145(12): 5847 - 5861. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Ameen, D. Linden, B.-M. Larsson, A. Mode, A. Holmang, and J. Oscarsson Effects of gender and GH secretory pattern on sterol regulatory element-binding protein-1c and its target genes in rat liver Am J Physiol Endocrinol Metab, December 1, 2004; 287(6): E1039 - E1048. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. V. Chirieac, H. L. Collins, J. Cianci, J. D. Sparks, and C. E. Sparks Altered triglyceride-rich lipoprotein production in Zucker diabetic fatty rats Am J Physiol Endocrinol Metab, July 1, 2004; 287(1): E42 - E49. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Frick, D. Linden, C. Ameen, S. Eden, A. Mode, and J. Oscarsson Interaction between growth hormone and insulin in the regulation of lipoprotein metabolism in the rat Am J Physiol Endocrinol Metab, November 1, 2002; 283(5): E1023 - E1031. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Journal of Biological Chemistry |
| Molecular and Cellular Proteomics | ASBMB Today |