High-mobility group box-1 mediates toll-like receptor 4-dependent angiogenesis

Qing Lin, Xiao Ping Yang, Dan Fang, Xiangrong Ren, Hongyan Zhou, Jiazhu Fang, Xialin Liu, Shiyou Zhou, Feng Wen, Xiaohong Yao, Ji Ming Wang, Shao Bo Su

Research output: Contribution to journalArticle

Abstract

Objective- Inflammation is closely linked to angiogenesis, and Toll-like receptors (TLRs) are the key mediators of inflammatory responses. However, the impact of TLRs on angiogenesis is incompletely understood. In this study, we determined the involvement of TLRs in angiogenesis. Methods and Results- In a mouse model of alkali-induced corneal neovascularization (CNV), we found that CNV was attenuated in TLR4-/- but not TLR2-/- mice. Further study revealed that the absence of TLR4 led to decreased production of proangiogenic factors in association with reduced accumulation of macrophages at the site of wounds, which was associated with reduced expression of high-mobility group box-1 (HMGB1) protein, an endogenous ligand for TLR4 -/-. Topical application of HMGB1 to the injured cornea promoted CNV with increased macrophage accumulation in wild-type mice but not in TLR4 mice. HMGB1 treatment in vitro also promoted the production of proangiogenic factors by mouse macrophages in a TLR4-dependent manner. Furthermore, antagonists of HMGB1 and TLR4 reduced CNV and macrophage recruitment in the injured cornea of wild-type mice. Conclusion- Our results suggest that the release of HMGB1 in the wounds initiates TLR4-dependent responses that contribute to neovascularization. Thus, targeting HMGB1-TLR4 signaling cascade may constitute a novel therapeutic approach to angiogenesis-related diseases.

Original languageEnglish (US)
Pages (from-to)1024-1032
Number of pages9
JournalArteriosclerosis, thrombosis, and vascular biology
Volume31
Issue number5
DOIs
StatePublished - May 2011
Externally publishedYes

    Fingerprint

Keywords

  • HMGB1
  • Toll-like receptor
  • angiogenesis
  • inflammation
  • macrophages

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

Cite this

Lin, Q., Yang, X. P., Fang, D., Ren, X., Zhou, H., Fang, J., Liu, X., Zhou, S., Wen, F., Yao, X., Wang, J. M., & Su, S. B. (2011). High-mobility group box-1 mediates toll-like receptor 4-dependent angiogenesis. Arteriosclerosis, thrombosis, and vascular biology, 31(5), 1024-1032. https://doi.org/10.1161/ATVBAHA.111.224048