Inhibition of endothelial activation: a new way to treat cerebral malaria?

PLoS Med. 2005 Sep;2(9):e245. doi: 10.1371/journal.pmed.0020245. Epub 2005 Aug 23.

Abstract

Background: Malaria is still a major public health problem, partly because the pathogenesis of its major complication, cerebral malaria (CM), remains incompletely understood. However tumor necrosis factor (TNF) is thought to play a key role in the development of this neurological syndrome, as well as lymphotoxin alpha (LT).

Methods and findings: Using an in vitro model of CM based on human brain-derived endothelial cells (HBEC-5i), we demonstrate the anti-inflammatory effect of LMP-420, a 2-NH2-6-Cl-9-[(5-dihydroxyboryl)-pentyl] purine that is a transcriptional inhibitor of TNF. When added before or concomitantly to TNF, LMP-420 inhibits endothelial cell (EC) activation, i.e., the up-regulation of both ICAM-1 and VCAM-1 on HBEC-5i surfaces. Subsequently, LMP-420 abolishes the cytoadherence of ICAM-1-specific Plasmodium falciparum-parasitized red blood cells on these EC. Identical but weaker effects are observed when LMP-420 is added with LT. LMP-420 also causes a dramatic reduction of HBEC-5i vesiculation induced by TNF or LT stimulation, as assessed by microparticle release.

Conclusion: These data provide evidence for a strong in vitro anti-inflammatory effect of LMP-420 and suggest that targeting host cell pathogenic mechanisms might provide a new therapeutic approach to improving the outcome of CM patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / pharmacology*
  • Antimalarials / pharmacology*
  • Boron Compounds / pharmacology
  • CD40 Antigens / metabolism
  • Cell Adhesion / drug effects
  • Cell Line
  • Endothelial Cells / drug effects*
  • Endothelial Cells / metabolism
  • Endothelial Cells / parasitology
  • Erythrocytes / drug effects
  • Erythrocytes / parasitology
  • Humans
  • Intercellular Adhesion Molecule-1 / metabolism
  • Plasmodium falciparum / drug effects*
  • Plasmodium falciparum / isolation & purification
  • Purine Nucleosides / pharmacology
  • Purines / pharmacology
  • Time Factors
  • Tumor Necrosis Factor-alpha / pharmacology
  • Vascular Cell Adhesion Molecule-1 / metabolism

Substances

  • 2-amino-6-chloro-9-((5-dihydroxyboryl)pentyl)purine
  • Anti-Inflammatory Agents
  • Antimalarials
  • Boron Compounds
  • CD40 Antigens
  • Purine Nucleosides
  • Purines
  • Tumor Necrosis Factor-alpha
  • Vascular Cell Adhesion Molecule-1
  • Intercellular Adhesion Molecule-1