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Fas activation in adipocytes impairs insulin-stimulated glucose uptake by reducing Akt

Stephan Wueest1, Reto A Rapold, Eugen J Schoenle

  • 1Division of Pediatric Endocrinology and Diabetology, University Children's Hospital, Zurich, Switzerland.

FEBS Letters
|September 11, 2010
PubMed

Insights

Fas receptor activation in fat cells reduces insulin sensitivity by lowering Akt protein levels, impacting glucose uptake. This finding highlights Fas signaling

Area of Science:

  • Cell Biology
  • Molecular Endocrinology
  • Immunology

Background:

  • Fas (CD95) is a tumor necrosis factor (TNF) receptor superfamily member involved in apoptosis.
  • Fas also regulates non-apoptotic cellular processes, including proliferation and inflammation.
  • Insulin signaling is crucial for glucose homeostasis, primarily mediated by the Akt pathway.

Purpose of the Study:

  • To investigate the role of Fas activation in regulating insulin sensitivity in adipocytes.
  • To determine the effect of Fas signaling on insulin-stimulated glucose uptake and Akt pathway.
  • To compare insulin sensitivity in adipocytes from Fas-deficient and wild-type mice.

Main Methods:

  • Treatment of 3T3-L1 adipocytes with Fas ligand to activate Fas.
  • Measurement of insulin-stimulated glucose uptake.
  • Assessment of Akt protein expression and phosphorylation.
  • Analysis of adipocytes isolated from Fas-deficient and wild-type mice.

Main Results:

  • Fas activation in 3T3-L1 adipocytes decreased insulin-stimulated glucose uptake without affecting cell viability.
  • This reduction correlated with decreased Akt protein expression and phosphorylation.
  • Fas-deficient adipocytes exhibited enhanced insulin-stimulated glucose incorporation and higher Akt levels compared to wild-type.

Conclusions:

  • Fas receptor activation in adipocytes impairs insulin sensitivity.
  • Fas signaling negatively regulates Akt expression, thereby inhibiting insulin-stimulated glucose uptake.
  • Targeting Fas pathways may offer therapeutic strategies for metabolic disorders characterized by insulin resistance.

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