Myeloperoxidase is increased in human cerebral aneurysms and increases formation and rupture of cerebral aneurysms in mice.

Journal Article (Clinical Trial;Journal Article)

BACKGROUND AND PURPOSE: Cerebral aneurysm (CA) affects 3% of the population and is associated with hemodynamic stress and inflammation. Myeloperoxidase, a major oxidative enzyme associated with inflammation, is increased in patients with CA, but whether myeloperoxidase contributes to CA is not known. We tested the hypotheses that myeloperoxidase is increased within human CA and is critical for formation and rupture of CA in mice. METHODS: Blood was drawn from the lumen of CAs and femoral arteries of 25 patients who underwent endovascular coiling of CA, and plasma myeloperoxidase concentrations were measured with ELISA. Effects of endogenous myeloperoxidase on CA formation and rupture were studied in myeloperoxidase knockout mice and wild-type (WT) mice using an angiotensin II-elastase induction model of CA. In addition, effects of myeloperoxidase on inflammatory gene expression in endothelial cells were analyzed. RESULTS: Plasma concentrations of myeloperoxidase were 2.7-fold higher within CA than in femoral arterial blood in patients with CA. myeloperoxidase-positive cells were increased in aneurysm tissue compared with superficial temporal artery of patients with CA. Incidence of aneurysms and subarachnoid hemorrhage was significantly lower in myeloperoxidase knockout than in WT mice. In cerebral arteries, proinflammatory molecules, including tumor necrosis factor-α, cyclooxygenase-2 (COX2), chemokine (C-X-C motif) ligand 1 (CXCL1), chemokine (C motif) ligand (XCL1), matrix metalloproteinase (MMP) 8, cluster of differentiation 68 (CD68), and matrix metalloproteinase 13, and leukocytes were increased, and α-smooth muscle actin was decreased, in WT but not in myeloperoxidase knockout mice after induction of CA. Myeloperoxidase per se increased expression of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 in endothelial cells. CONCLUSIONS: These findings suggest that myeloperoxidase may contribute importantly to formation and rupture of CA.

Full Text

Duke Authors

Cited Authors

  • Chu, Y; Wilson, K; Gu, H; Wegman-Points, L; Dooley, SA; Pierce, GL; Cheng, G; Pena Silva, RA; Heistad, DD; Hasan, D

Published Date

  • June 2015

Published In

Volume / Issue

  • 46 / 6

Start / End Page

  • 1651 - 1656

PubMed ID

  • 25922506

Pubmed Central ID

  • PMC4418183

Electronic International Standard Serial Number (EISSN)

  • 1524-4628

Digital Object Identifier (DOI)

  • 10.1161/STROKEAHA.114.008589

Language

  • eng

Conference Location

  • United States