|
|
||||||||
Department of Pediatrics, Research and Education Institute, Harbor-UCLA Medical Center, Torrance, California 90502
De novo lipogenesis and dietary fat uptake are two major sources of fatty acid deposits in fat of obese animals. To determine the relative contribution of fatty acids from these two sources in obesity, we have determined the distribution of c16 and c18 fatty acids of triglycerides in plasma, liver, and epididymal fat pad of Zucker diabetic fatty (ZDF) rats and their lean littermates (ZL) under two isocaloric dietary fat conditions. Lipogenesis was also determined using the deuterated water method. Conversion of palmitate to stearate and stearate to oleate was calculated from the deuterium incorporation by use of the tracer dilution principle. In the ZL rat, lipogenesis was suppressed from 70 to 24%, conversion of palmitate to stearate from 86 to 78%, and conversion of stearate to oleate from 56 to 7% in response to an increase in the dietary fat-to-carbohydrate ratio. The results suggest that suppression of fatty acid synthase and stearoyl-CoA desaturase activities is a normal adaptive mechanism to a high-fat diet. In contrast, de novo lipogenesis, chain elongation, and desaturation were not suppressed by dietary fat in the ZDF rat. The lack of ability to adapt to a high-fat diet resulted in a higher plasma triglyceride concentration and excessive fat accumulation from both diet and de novo synthesis in the ZDF rat.
chain elongation; stearoyl-coenzyme A desaturase; tissue fatty acid composition
This article has been cited by other articles:
![]() |
K. Begriche, P. Letteron, A. Abbey-Toby, N. Vadrot, M.-A. Robin, A. Bado, D. Pessayre, and B. Fromenty Partial leptin deficiency favors diet-induced obesity and related metabolic disorders in mice Am J Physiol Endocrinol Metab, May 1, 2008; 294(5): E939 - E951. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. R. Bederman, D. A. Dufner, J. C. Alexander, and S. F. Previs Novel application of the "doubly labeled" water method: measuring CO2 production and the tissue-specific dynamics of lipid and protein in vivo Am J Physiol Endocrinol Metab, May 1, 2006; 290(5): E1048 - E1056. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Garg, S. Bassilian, C. Bell, S. Lee, and W. N. P. Lee Hepatic de Novo Lipogenesis in Stable Low-Birth-Weight Infants During Exclusive Breast Milk Feedings and During Parenteral Nutrition JPEN J Parenter Enteral Nutr, March 1, 2005; 29(2): 81 - 86. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |