Autophagy Ablation in Adipocytes Induces Insulin Resistance and Reveals Roles for Lipid Peroxide and Nrf2 Signaling in Adipose-Liver Crosstalk

Cell Rep. 2018 Nov 13;25(7):1708-1717.e5. doi: 10.1016/j.celrep.2018.10.040.

Abstract

Autophagy is a homeostatic cellular process involved in the degradation of long-lived or damaged cellular components. The role of autophagy in adipogenesis is well recognized, but its role in mature adipocyte function is largely unknown. We show that the autophagy proteins Atg3 and Atg16L1 are required for proper mitochondrial function in mature adipocytes. In contrast to previous studies, we found that post-developmental ablation of autophagy causes peripheral insulin resistance independently of diet or adiposity. Finally, lack of adipocyte autophagy reveals cross talk between fat and liver, mediated by lipid peroxide-induced Nrf2 signaling. Our data reveal a role for autophagy in preventing lipid peroxide formation and its transfer in insulin-sensitive peripheral tissues.

Keywords: adipocytes; adiponectin; adipose tissue; autophagy; inflammation; insulin resistance; lipid peroxide; mitochondria.

Publication types

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

MeSH terms

  • Adipocytes / cytology*
  • Adipocytes / metabolism
  • Adipose Tissue / metabolism*
  • Adipose Tissue, Brown / metabolism
  • Adipose Tissue, Brown / pathology
  • Adipose Tissue, White / metabolism
  • Adipose Tissue, White / pathology
  • Adiposity
  • Animals
  • Autophagy*
  • Autophagy-Related Proteins / metabolism
  • Body Composition
  • Body Weight
  • Humans
  • Inflammation / pathology
  • Insulin Resistance*
  • Kelch-Like ECH-Associated Protein 1 / metabolism
  • Lipid Peroxides / metabolism*
  • Lipoproteins, HDL / metabolism
  • Liver / metabolism*
  • Mice, Knockout
  • Mitochondria / metabolism
  • NF-E2-Related Factor 2 / metabolism*
  • Signal Transduction*
  • Ubiquitin-Conjugating Enzymes / metabolism

Substances

  • Atg16l1 protein, mouse
  • Autophagy-Related Proteins
  • Keap1 protein, mouse
  • Kelch-Like ECH-Associated Protein 1
  • Lipid Peroxides
  • Lipoproteins, HDL
  • NF-E2-Related Factor 2
  • Ubiquitin-Conjugating Enzymes
  • Atg3 protein, mouse