Anti-inflammatory effects of soyasapogenol I-αa via downregulation of the MAPK signaling pathway in LPS-induced RAW 264.7 macrophages

Food Chem Toxicol. 2018 Mar:113:211-217. doi: 10.1016/j.fct.2018.01.050. Epub 2018 Jan 31.

Abstract

The crude extract of soyasaponins was reported to possess anti-inflammatory activity. We determined the new purity group I saponin, I-αa and I-γa that was isolated from wild soybean (Glycine soja) in terms of its efficacy in protecting RAW 264.7 macrophages from lipopolysaccharide (LPS)-stimuli. Cells were treated with soyasaponin I-αa/I-γa (30-300 μΜ) and LPS (0.1 μg/mL) for 24 h. Soyasaponin I-αa inhibited nitric oxide (NO) production at 100 μg/mL, while soyasaponin I-γa demonstrated this effect at a higher concentration (200 μg/mL). The expression levels of iNOS and COX-2 enzymes were downregulated by both soyasaponins. Soyasaponin I-αa exerted its effect via the TNF-α and IL-1β cytokines. However, soyasaponin I-γa only inhibited the expression of TNF-α. The inflammatory effect of group I soyasaponin was mainly mediated via the phosphorylation of the p38 and JNK proteins. Collectively, these results suggested the potential anti-inflammatory effects of soyasaponins.

Keywords: Cytokines; Glycine soja; Inflammatory; Macrophage; Soyasaponin.

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / pharmacology*
  • Cyclooxygenase 2 / metabolism
  • Down-Regulation / drug effects*
  • Glycine max / chemistry
  • Interleukin-1beta / metabolism
  • Lipopolysaccharides / pharmacology*
  • MAP Kinase Signaling System / drug effects*
  • Macrophages / drug effects*
  • Mice
  • Nitric Oxide / antagonists & inhibitors
  • Nitric Oxide / biosynthesis
  • Nitric Oxide Synthase Type II / metabolism
  • Oleanolic Acid / analogs & derivatives*
  • Oleanolic Acid / pharmacology
  • Plant Extracts / pharmacology
  • RAW 264.7 Cells
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Anti-Inflammatory Agents
  • Interleukin-1beta
  • Lipopolysaccharides
  • Plant Extracts
  • Tumor Necrosis Factor-alpha
  • Nitric Oxide
  • soyasapogenol A
  • Oleanolic Acid
  • Nitric Oxide Synthase Type II
  • Cyclooxygenase 2