Triglyceride Synthesis by DGAT1 Protects Adipocytes from Lipid-Induced ER Stress during Lipolysis.
Cell Metab
; 26(2): 407-418.e3, 2017 Aug 01.
Article
in En
| MEDLINE
| ID: mdl-28768178
Triglyceride (TG) storage in adipose tissue provides the major reservoir for metabolic energy in mammals. During lipolysis, fatty acids (FAs) are hydrolyzed from adipocyte TG stores and transported to other tissues for fuel. For unclear reasons, a large portion of hydrolyzed FAs in adipocytes is re-esterified to TGs in a "futile," ATP-consuming, energy dissipating cycle. Here we show that FA re-esterification during adipocyte lipolysis is mediated by DGAT1, an ER-localized DGAT enzyme. Surprisingly, this re-esterification cycle does not preserve TG mass but instead functions to protect the ER from lipotoxic stress and related consequences, such as adipose tissue inflammation. Our data reveal an important role for DGAT activity and TG synthesis generally in averting ER stress and lipotoxicity, with specifically DGAT1 performing this function during stimulated lipolysis in adipocytes.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Triglycerides
/
Adipocytes
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Diacylglycerol O-Acyltransferase
/
Endoplasmic Reticulum Stress
/
Lipolysis
Limits:
Animals
/
Humans
Language:
En
Journal:
Cell Metab
Journal subject:
METABOLISMO
Year:
2017
Document type:
Article
Affiliation country:
United States
Country of publication:
United States