Document Type

Article

Publication Date

2-28-2014

Comments

This article has been peer reviewed. It was published in: Circulation Research.

Volume 114, Issue 5, 28 February 2014, Pages 792-805.

The published version is available at DOI: 10.1161/CIRCRESAHA.114.302439

Copyright © 2014 American Heart Association, Inc.

Abstract

RATIONALE: Anti-inflammatory and vascular protective actions of adiponectin are well recognized. However, many fundamental questions remain unanswered.

OBJECTIVE: The current study attempted to identify the adiponectin receptor subtype responsible for adiponectin's vascular protective action and investigate the role of ceramidase activation in adiponectin anti-inflammatory signaling.

METHODS AND RESULTS: Adiponectin significantly reduced tumor necrosis factor (TNF)α-induced intercellular adhesion molecule-1 expression and attenuated TNFα-induced oxidative/nitrative stress in human umbilical vein endothelial cells. These anti-inflammatory actions were virtually abolished by adiponectin receptor 1 (AdipoR1-), but not AdipoR2-, knockdown (KD). Treatment with adiponectin significantly increased neutral ceramidase (nCDase) activity (3.7-fold; P87% of adiponectin-induced nCDase activation was lost. Whereas adiponectin treatment failed to inhibit TNFα-induced intercellular adhesion molecule-1 expression, treatment with sphingosine-1-phosphate or SEW (sphingosine-1-phosphate receptor agonist) remained effective in Cav1-KD cells. AdipoR1 and Cav1 colocalized and coprecipitated in human umbilical vein endothelial cells. Adiponectin treatment did not affect this interaction. There is weak basal Cav1/nCDase interaction, which significantly increased after adiponectin treatment. Knockout of AdipoR1 or Cav1 abolished the inhibitory effect of adiponectin on leukocyte rolling and adhesion in vivo.

CONCLUSIONS: These results demonstrate for the first time that adiponectin inhibits TNFα-induced inflammatory response via Cav1-mediated ceramidase recruitment and activation in an AdipoR1-dependent fashion.

Included in

Pathology Commons

Share

COinS