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标题：Insights into the requirement of phosphatidylcholine synthesis for liver function in mice
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作者：Anna A. Noga ; Dennis E. Vance
期刊名称：JLR Papers In Press
印刷版ISSN：0022-2275
电子版ISSN：1539-7262
出版年度：2003
卷号：44
期号：10
页码：1998-2005
DOI：10.1194/jlr.M300226-JLR200
语种：English
出版社：American Society for Biochemistry and Molecular Biology
摘要：Phosphatidylcholine (PC) is made in the liver by the CDP-choline pathway and via phosphatidylethanolamine N -methyltransferase (PEMT), which catalyzes the conversion of phosphatidylethanolamine to PC. Unexpectedly, hepatic apolipoprotein B-100 secretion is inhibited in male, but not female, Pemt ^−/− mice (Noga, A. A., Y. Zhao, and D. E. Vance. 2002. J. Biol. Chem. 277: 42358–42365; Noga, A. A., and D. E. Vance. 2003. J. Biol. Chem. 278: 21851–21859). To gain further insight into this process, we compared PC metabolism in male and female mice fed chow or a high-fat/high-cholesterol (HF/HC) diet. Immunoblot analyses demonstrated that twice as much PEMT2 was present in livers from female compared with male mice. In contrast, assays of CTP:phosphocholine cytidylyltransferase from livers of Pemt ^+/+ mice demonstrated more active cytidylyltransferase in male than in female mice. Secretion of PEMT-derived PC into lipoproteins was examined in vivo by injection of mice with [methyl-³H]methionine in the presence of Triton WR1339. The PEMT-derived PC shifts to smaller-sized particles in response to a HF/HC diet, but only in male mice. Secretion of PEMT-derived PC into bile was enhanced in mice fed a HF/HC diet. These results demonstrate that the synthesis and targeting of PC produced by the PEMT pathway in the livers of mice differs in a gender- and diet-specific manner.