Esculetin inhibits the inflammatory response by inducing heme oxygenase-1 in cocultured macrophages and adipocytes

Food Funct. 2014 Sep;5(9):2371-7. doi: 10.1039/c4fo00351a.

Abstract

Obesity is associated with chronic low-grade inflammation of adipose tissue. In this study, we investigated the anti-inflammatory effects of esculetin (ECT) through up-regulation of heme oxygenase-1 (HO-1) in cocultured macrophages and adipocytes. RAW264.7 macrophages and differentiated 3T3-L1 adipocytes were cocultured in serum-free Dulbecco's modified Eagle's medium with or without ECT for 24 h. Nitric oxide (NO), tumor necrosis factor-α (TNF-α), and monocyte chemoattractant protein-1 (MCP-1) production was measured in the coculture supernatant. ECT decreased the secretion of NO, TNF-α, and MCP-1. The expression of adipogenic proteins, including peroxisome proliferator-activated receptors γ (PPARγ) and CCAAT/enhancer binding protein α (C/EBPα) in cocultured adipocytes and inducible nitric oxide synthase (iNOS) in cocultured macrophages, was inhibited by ECT. Additionally, HO-1 expression was induced in cocultured macrophages and adipocytes. Silencing of HO-1 expression increased the production of NO, TNF-α, and MCP-1 in cocultured cells, in spite of the presence of ECT. This study demonstrated that ECT exhibited anti-inflammatory properties by inhibiting the production of proinflammatory cytokines in the interaction between adipocytes and macrophages through HO-1 expression. ECT may have the potential to improve chronic inflammation in obesity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3-L1 Cells
  • Adipocytes / drug effects*
  • Adipocytes / immunology
  • Animals
  • CCAAT-Enhancer-Binding Protein-alpha / genetics
  • CCAAT-Enhancer-Binding Protein-alpha / immunology
  • Coculture Techniques
  • Heme Oxygenase-1 / genetics
  • Heme Oxygenase-1 / immunology*
  • Macrophages / drug effects*
  • Macrophages / immunology
  • Mice
  • PPAR gamma / genetics
  • PPAR gamma / immunology
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / immunology
  • Umbelliferones / pharmacology*

Substances

  • CCAAT-Enhancer-Binding Protein-alpha
  • PPAR gamma
  • Tumor Necrosis Factor-alpha
  • Umbelliferones
  • Heme Oxygenase-1
  • esculetin