Effect of zinc-alpha 2-glycoprotein (ZAG) on expression of uncoupling proteins in skeletal muscle and adipose tissue

Paul M. Sanders, Michael J. Tisdale*

*Corresponding author for this work

Research output: Contribution to journalArticle

Abstract

The plasma protein zinc-α2-glycoprotein (ZAG) has been shown to be identical with a lipid mobilizing factor capable of inducing loss of adipose tissue in cancer cachexia through an increased lipid mobilization and utilization. The ability of ZAG to induce uncoupling protein (UCP) expression has been determined using in vitro models of adipose tissue and skeletal muscle. ZAG induced a concentration-dependent increase in the expression of UCP-1 in primary cultures of brown, but not white, adipose tissue, and this effect was attenuated by the β3-adrenergic receptor (β3-AR) antagonist SR59230A. A 6.5-fold increase in UCP-1 expression was found in brown adipose tissue after incubation with 0.58 μM ZAG. ZAG also increased UCP-2 expression 3.5-fold in C2C12 murine myotubes, and this effect was also attenuated by SR59230A and potentiated by isobutylmethylxanthine, suggesting a cyclic AMP-mediated process through interaction with a β3-AR. ZAG also produced a dose-dependent increase in UCP-3 in murine myotubes with a 2.5-fold increase at 0.58 μM ZAG. This effect was not mediated through the β3-AR, but instead appeared to require mitogen activated protein kinase. These results confirm the ability of ZAG to directly influence UCP expression, which may play an important role in lipid utilization during cancer cachexia. © 2004 Elsevier Ireland Ltd. All rights reserved.

Original languageEnglish
Pages (from-to)71-81
Number of pages11
JournalCancer Letters
Volume212
Issue number1
DOIs
Publication statusPublished - Aug 2004

Keywords

  • BAT, brown adipose tissue
  • cancer cachexia
  • UCP
  • uncoupling proteins
  • WAT, white adipose tissue
  • ZAG
  • Zinc-α-glycoprotein

Fingerprint Dive into the research topics of 'Effect of zinc-alpha 2-glycoprotein (ZAG) on expression of uncoupling proteins in skeletal muscle and adipose tissue'. Together they form a unique fingerprint.

  • Cite this