Metabolic importance of adipose tissue monoacylglycerol acyltransferase 1 in mice and humans

J Lipid Res. 2018 Sep;59(9):1630-1639. doi: 10.1194/jlr.M084947. Epub 2018 May 31.

Abstract

Adipocyte triglyceride storage provides a reservoir of energy that allows the organism to survive times of nutrient scarcity, but excessive adiposity has emerged as a health problem in many areas of the world. Monoacylglycerol acyltransferase (MGAT) acylates monoacylglycerol to produce diacylglycerol; the penultimate step in triglyceride synthesis. However, little is known about MGAT activity in adipocytes, which are believed to rely primarily on another pathway for triglyceride synthesis. We show that expression of the gene that encodes MGAT1 is robustly induced during adipocyte differentiation and that its expression is suppressed in fat of genetically-obese mice and metabolically-abnormal obese human subjects. Interestingly, MGAT1 expression is also reduced in physiologic contexts where lipolysis is high. Moreover, knockdown or knockout of MGAT1 in adipocytes leads to higher rates of basal adipocyte lipolysis. Collectively, these data suggest that MGAT1 activity may play a role in regulating basal adipocyte FFA retention.

Keywords: adipocytes; fatty acid; fatty acid re-esterification; lipids; lipolysis; lipolysis and fatty acid metabolism.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acyltransferases / deficiency
  • Acyltransferases / genetics
  • Acyltransferases / metabolism*
  • Adipocytes / cytology
  • Adipose Tissue / enzymology*
  • Adipose Tissue / metabolism
  • Animals
  • Cell Differentiation
  • Fatty Acids, Nonesterified / metabolism
  • Gene Expression Regulation, Enzymologic
  • Gene Knockdown Techniques
  • Humans
  • Male
  • Mice
  • N-Acetylglucosaminyltransferases / deficiency
  • N-Acetylglucosaminyltransferases / genetics
  • N-Acetylglucosaminyltransferases / metabolism*
  • Obesity / metabolism
  • Obesity / pathology
  • RNA, Small Interfering / genetics

Substances

  • Fatty Acids, Nonesterified
  • RNA, Small Interfering
  • Acyltransferases
  • MGAT1 protein, human
  • MGAT1 protein, mouse
  • N-Acetylglucosaminyltransferases