β-Glucan attenuates inflammatory responses in oxidized LDL-induced THP-1 cells via the p38 MAPK pathway

Nutr Metab Cardiovasc Dis. 2014 Mar;24(3):248-55. doi: 10.1016/j.numecd.2013.09.019. Epub 2013 Nov 7.

Abstract

Aim: To investigate the immunomodulatory effects of β-(1,3/1,6)-d-glucan on atherosclerosis as well as on the molecular mechanisms of its transition.

Methods and results: Human monocytic leukemia (THP-1) cells were differentiated into the macrophage phenotype by incubation with oxLDL in the absence or presence of β-glucan. β-glucan attenuated CD86 and CD80 expression and simultaneously reduced secretion of the inflammatory cytokines IL-2, IL-8, IL-12, TNF-α and IFN-γ. Western blot analysis showed that oxLDL treatment induced phosphorylation of p38 MAPK and ERK1/2 in PMA-differentiated THP-1 cells. However, β-glucan inhibited p38 MAPK activation. In experiments with monocytes derived from healthy donors, β-glucan inhibited IL-8, IL-12 and TNF-α production. The anti-inflammatory effects of β-glucan were also observed in atherosclerotic plaque cells.

Conclusions: β-glucan inhibited oxLDL-induced pro-inflammatory effects in macrophages via regulation of p38 MAPK phosphorylation. This novel finding may provide insight for new therapeutic strategies.

Keywords: Atherosclerosis; Macrophage; p38 MAPK; β-Glucan.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Inflammatory Agents / pharmacology*
  • Cell Differentiation
  • Cell Line, Tumor
  • Humans
  • Inflammation / metabolism*
  • Interferon-gamma / metabolism
  • Interleukin-12 / metabolism
  • Interleukin-8 / metabolism
  • Lipoproteins, LDL / administration & dosage
  • Lipoproteins, LDL / adverse effects
  • MAP Kinase Signaling System*
  • Macrophages / metabolism
  • Monocytes / drug effects
  • Monocytes / metabolism
  • Phosphorylation
  • Tumor Necrosis Factor-alpha / metabolism
  • beta-Glucans / pharmacology*
  • p38 Mitogen-Activated Protein Kinases / genetics
  • p38 Mitogen-Activated Protein Kinases / metabolism*

Substances

  • Anti-Inflammatory Agents
  • Interleukin-8
  • Lipoproteins, LDL
  • Tumor Necrosis Factor-alpha
  • beta-Glucans
  • oxidized low density lipoprotein
  • Interleukin-12
  • Interferon-gamma
  • p38 Mitogen-Activated Protein Kinases