Recombinant human sonic hedgehog protein regulates the expression of ZO-1 and occludin by activating angiopoietin-1 in stroke damage

PLoS One. 2013 Jul 23;8(7):e68891. doi: 10.1371/journal.pone.0068891. Print 2013.

Abstract

This study examines the regulating effect of Sonic Hedgehog (Shh) on the permeability of the blood-brain barrier (BBB) in cerebral ischemia. By employing permanent middle cerebral artery occlusion (pMCAO) model, we find that Shh significantly decreases brain edema and preserves BBB permeability. Moreover, Shh increases zonula occludens-1 (ZO-1), occludin and angiopiotetin-1 (Ang-1) expression in the ischemic penumbra. Blockage of Shh with cyclopamine abolishes the effects of Shh on brain edema, BBB permeability and ZO-1, occludin, Ang-1 expression. Primary brain microvessel endothelial cells (BMECs) and astrocytes were pre-treated with Shh, cyclopamine, Ang-1-neutralizing antibody, and subjected to oxygen-glucose deprivation (OGD). Results show that the Ang-1 protein level in the culture medium of Shh-treated astrocytes is significantly higher. Shh also increased ZO-1, occludin and Ang-1 expression in BMECs, while cyclopamine and Ang-1-neutralizing antibody inhibited the effects of Shh on the ZO-1 and occludin expression, respectively. This study suggests that, under ischemic insults, Shh triggers Ang-1 production predominantly in astrocytes, and the secreted Ang-1 acts on BMECs, thereby upregulating ZO-1 and occludin to repair the tight junction and ameliorate the brain edema and BBB leakage.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiopoietin-1 / metabolism*
  • Animals
  • Astrocytes / metabolism
  • Blood-Brain Barrier / metabolism
  • Brain Ischemia / metabolism
  • Brain Ischemia / physiopathology
  • Hedgehog Proteins / genetics
  • Hedgehog Proteins / metabolism*
  • Humans
  • Occludin / biosynthesis*
  • Rats
  • Rats, Sprague-Dawley
  • Recombinant Proteins / metabolism
  • Stroke / genetics*
  • Stroke / metabolism
  • Stroke / physiopathology
  • Up-Regulation
  • Zonula Occludens-1 Protein / biosynthesis*

Substances

  • Angiopoietin-1
  • Angpt1 protein, rat
  • Hedgehog Proteins
  • Occludin
  • Ocln protein, rat
  • Recombinant Proteins
  • SHH protein, human
  • Zonula Occludens-1 Protein

Grants and funding

This work was supported by grants 81070938 from the Program of National Natural Science Foundation of China, grant 81101905 from the Program of National Natural Science Foundation of China, New Century Excellent Talents in University NCET-10-0406 and the Fundamental Research Funds for the Central Universities, HUST No.2010JC028, HUST No. 2011JC069. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.