Attenuation of plasma annexin A1 in human obesity

FASEB J. 2013 Jan;27(1):368-78. doi: 10.1096/fj.12-213728. Epub 2012 Oct 4.

Abstract

Obesity-related metabolic disorders are characterized by mild chronic inflammation, leukocyte infiltration, and tissue fibrosis as a result of adipocytokine production from the expanding white adipose tissue. Annexin A1 (AnxA1) is an endogenous glucocorticoid regulated protein, which modulates systemic anti-inflammatory processes and, therefore, may be altered with increasing adiposity in humans. Paradoxically, we found that plasma AnxA1 concentrations inversely correlated with BMI, total percentage body fat, and waist-to-hip ratio in human subjects. Plasma AnxA1 was also inversely correlated with plasma concentrations of the acute-phase protein, C-reactive protein (CRP), and the adipocytokine leptin, suggesting that as systemic inflammation increases, anti-inflammatory AnxA1 is reduced. In addition, AnxA1 gene expression and protein were significantly up-regulated during adipogenesis in a human adipocyte cell line compared to vehicle alone, demonstrating for the first time that AnxA1 is expressed and excreted from human adipocytes. These data demonstrate a failure in the endogenous anti-inflammatory system to respond to increasing systemic inflammation resulting from expanding adipose tissue, a condition strongly linked to the development of type 2 diabetes and cardiovascular disease. These data raise the possibility that a reduction in plasma AnxA1 may contribute to the chronic inflammatory phenotype observed in human obesity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Annexin A1 / blood*
  • Biomarkers / blood
  • C-Reactive Protein / metabolism
  • Cells, Cultured
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Inflammation Mediators / blood
  • Leptin / blood
  • Male
  • Obesity / blood*
  • Real-Time Polymerase Chain Reaction

Substances

  • Annexin A1
  • Biomarkers
  • Inflammation Mediators
  • Leptin
  • C-Reactive Protein