Regulation of Plasminogen Activator Inhibitor-1 in Adipocytes by Macrophages Activated by Low-dose Lipopolysaccharide

Anticancer Res. 2021 Aug;41(8):4071-4076. doi: 10.21873/anticanres.15208.


Background/aim: Increased expression of inflammatory cytokine genes through cell interactions in tissues may cause chronic inflammation, leading to the development of lifestyle-related diseases. Since the activation of inflammatory cytokine genes in monocytes/macrophages by co-culturing with cancer cells or adipocytes was suppressed by pre-treatment with low-dose lipopolysaccharide (LPS), we hypothesized that low-dose LPS-activated macrophages may regulate the expression of immune response-related genes in other cells.

Materials and methods: Phorbol myristate acetate-treated human monocytes (THP-1) were activated by LPS. The conditioned medium of LPS-activated THP-1 cells was added to human adipocytes. After 5 days, the expression of genes encoding interleukin (IL)-6 (IL6), IL-8 (IL8), monocyte chemotactic protein (MCP)-1 (CCL2), adiponectin (ADIPOQ), and plasminogen activator inhibitor (PAI)-1 (SERPINE1) was analyzed using quantitative real-time PCR.

Results: The increased expression of inflammation-related genes and SERPINE1 in adipocytes was suppressed by the conditioned medium of THP-1 cells activated by low-dose LPS, whereas the expression of ADIPOQ was significantly increased.

Conclusion: Low-dose LPS-activated macrophages convert adipocytes to anti-inflammatory phenotypes.

Keywords: Macrophage; adipocyte; inflammatory cytokine genes; lipopolysaccharide; plasminogen activator inhibitor-1.

MeSH terms

  • Adipocytes / metabolism*
  • Adiponectin / genetics*
  • Cell Line
  • Cytokines / genetics*
  • Humans
  • Lipopolysaccharides / pharmacology*
  • Macrophage Activation
  • Macrophages / drug effects*
  • Plasminogen Activator Inhibitor 1 / genetics*


  • ADIPOQ protein, human
  • Adiponectin
  • Cytokines
  • Lipopolysaccharides
  • Plasminogen Activator Inhibitor 1
  • SERPINE1 protein, human