Author:
Werner Anniek,Havinga Rick,Bos Trijnie,Bloks Vincent W.,Kuipers Folkert,Verkade Henkjan J.
Abstract
Essential fatty acid (EFA) deficiency in mice decreases plasma triglyceride (TG) concentrations and increases hepatic TG content. We evaluated in vivo and in vitro whether decreased hepatic secretion of TG-rich very low-density lipoprotein (VLDL) contributes to this consequence of EFA deficiency. EFA deficiency was induced in mice by feeding an EFA-deficient (EFAD) diet for 8 wk. Hepatic VLDL secretion was quantified in fasted EFAD and EFA-sufficient (EFAS) mice using the Triton WR-1339 method. In cultured hepatocytes from EFAD and EFAS mice, VLDL secretion into medium was measured by quantifying [3H]-labeled glycerol incorporation into TG and phospholipids. Hepatic expression of genes involved in VLDL synthesis and clearance was measured, as were plasma activities of lipolytic enzymes. TG secretion rates were quantitatively similar in EFAD and EFAS mice in vivo and in primary hepatocytes from EFAD and EFAS mice in vitro. However, EFA deficiency increased the size of secreted VLDL particles, as determined by calculation of particle diameter, particle sizing by light scattering, and evaluation of the TG-to-apoB ratio. EFA deficiency did not inhibit hepatic lipase and lipoprotein lipase activities in plasma, but increased hepatic mRNA levels of apoAV and apoCII, both involved in control of lipolytic degradation of TG-rich lipoproteins. EFA deficiency does not affect hepatic TG secretion rate in mice, but increases the size of secreted VLDL particles. Present data suggest that hypotriglyceridemia during EFA deficiency is related to enhanced clearance of altered VLDL particles.
Publisher
American Physiological Society
Subject
Physiology (medical),Gastroenterology,Hepatology,Physiology
Reference54 articles.
1. Abdel-Fattah G, Fernandez ML, and McNamara DJ.Regulation of guinea pig very low density lipoprotein secretion rates by dietary fat saturation.J Lipid Res36: 1188–1198, 1995.
2. Regulation of very low density lipoprotein apo B metabolism by dietary fat saturation and chain length in the guinea pig
3. Changes in Tissue Lipids and Tissue Histology Resulting from Essential Fatty Acid Deficiency in Rats
4. Allmann Dand Gibson D.Fatty acids synthesis during early linoleic acid deficiency in the mouse.J Lipid Res79: 51–62, 1965.
5. Bennett Clark S, Ekkers TE, Singh A, Balint JA, Holt PR, and Rodgers JB.Fat absorption in essential fatty acid deficiency: a model experimental approach to studies of the mechanism of fat malabsorption of unknown etiology.J Lipid Res14: 581–588, 1973.
Cited by
38 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献