文章基本信息

标题：Autophagy regulates sphingolipid levels in the liver
本地全文：下载
作者：Aikaterini Alexaki ; Sita D. Gupta ; Saurav Majumder 等
期刊名称：JLR Papers In Press
印刷版ISSN：0022-2275
电子版ISSN：1539-7262
出版年度：2014
卷号：55
期号：12
页码：2521-2531
DOI：10.1194/jlr.M051862
语种：English
出版社：American Society for Biochemistry and Molecular Biology
摘要：Sphingolipid levels are tightly regulated to maintain cellular homeostasis. During pathologic conditions such as in aging, inflammation, and metabolic and neurodegenerative diseases, levels of some sphingolipids, including the bioactive metabolite ceramide, are elevated. Sphingolipid metabolism has been linked to autophagy, a critical catabolic process in both normal cell function and disease; however, the in vivo relevance of the interaction is not well-understood. Here, we show that blocking autophagy in the liver by deletion of the Atg7 gene, which is essential for autophagosome formation, causes an increase in sphingolipid metabolites including ceramide. We also show that overexpression of serine palmitoyltransferase to elevate de novo sphingolipid biosynthesis induces autophagy in the liver. The results reveal autophagy as a process that limits excessive ceramide levels and that is induced by excessive elevation of de novo sphingolipid synthesis in the liver. Dysfunctional autophagy may be an underlying mechanism causing elevations in ceramide that may contribute to pathogenesis in diseases.
关键词：ceramide ; lipids ; endoplasmic reticulum ; triglycerides ; lipophagy