Sophora flavescens protects against mycobacterial Trehalose Dimycolate-induced lung granuloma by inhibiting inflammation and infiltration of macrophages

Sci Rep. 2018 Mar 2;8(1):3903. doi: 10.1038/s41598-018-22286-w.

Abstract

The immune system responds to Mycobacterium tuberculosis (MTB) infection by forming granulomas to quarantine the bacteria from spreading. Granuloma-mediated inflammation is a cause of lung destruction and disease transmission. Sophora flavescens (SF) has been demonstrated to exhibit bactericidal activities against MTB. However, its immune modulatory activities on MTB-mediated granulomatous inflammation have not been reported. In the present study, we found that flavonoids from Sophora flavescens (FSF) significantly suppressed the pro-inflammatory mediators released from mouse lung alveolar macrophages (MH-S) upon stimulation by trehalose dimycolate (TDM), the most abundant lipoglycan on MTB surface. Moreover, FSF reduced adhesion molecule (LFA-1) expression on MH-S cells after TDM stimulation. Furthermore, FSF treatment on TDM-activated lung epithelial (MLE-12) cells significantly downregulated macrophage chemoattractant protein (MCP-1/CCL2) expression, which in turn reduced the in vitro migration of MH-S to MLE-12 cells. In addition, FSF increased the clearance of mycobacterium bacteria (Mycobacterium aurum) in macrophages. FSF mainly affected the Mincle-Syk-Erk signaling pathway in TDM-activated MH-S cells. In TDM-induced mouse granulomas model, oral administration with FSF significantly suppressed lung granulomas formation and inflammation. These findings collectively implicated an anti-inflammatory role of FSF on MTB-mediated granulomatous inflammation, thereby providing evidence of FSF as an efficacious adjunct treatment during mycobacterial infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adjuvants, Immunologic / toxicity
  • Animals
  • Cells, Cultured
  • Cord Factors / toxicity*
  • Cytokines / metabolism
  • Flavonoids / pharmacology*
  • Granuloma, Respiratory Tract / chemically induced
  • Granuloma, Respiratory Tract / immunology
  • Granuloma, Respiratory Tract / prevention & control*
  • Inflammation / chemically induced
  • Inflammation / immunology
  • Inflammation / prevention & control*
  • Lung Diseases / chemically induced
  • Lung Diseases / immunology
  • Lung Diseases / prevention & control*
  • Macrophages / drug effects*
  • Macrophages / immunology
  • Macrophages / pathology
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mycobacterium / metabolism
  • Mycobacterium / pathogenicity
  • Protective Agents / pharmacology
  • Sophora / chemistry*

Substances

  • Adjuvants, Immunologic
  • Cord Factors
  • Cytokines
  • Flavonoids
  • Protective Agents