Heme Oxygenase-1 Expression Affects Murine Abdominal Aortic Aneurysm Progression

PLoS One. 2016 Feb 19;11(2):e0149288. doi: 10.1371/journal.pone.0149288. eCollection 2016.

Abstract

Heme oxygenase-1 (HO-1), the rate-limiting enzyme in heme degradation, is a cytoprotective enzyme upregulated in the vasculature by increased flow and inflammatory stimuli. Human genetic data suggest that a diminished HO-1 expression may predispose one to abdominal aortic aneurysm (AAA) development. In addition, heme is known to strongly induce HO-1 expression. Utilizing the porcine pancreatic elastase (PPE) model of AAA induction in HO-1 heterozygous (HO-1+/-, HO-1 Het) mice, we found that a deficiency in HO-1 leads to augmented AAA development. Peritoneal macrophages from HO-1+/- mice showed increased gene expression of pro-inflammatory cytokines, including MCP-1, TNF-alpha, IL-1-beta, and IL-6, but decreased expression of anti-inflammatory cytokines IL-10 and TGF-beta. Furthermore, treatment with heme returned AAA progression in HO-1 Het mice to a wild-type profile. Using a second murine AAA model (Ang II-ApoE-/-), we showed that low doses of the HMG-CoA reductase inhibitor rosuvastatin can induce HO-1 expression in aortic tissue and suppress AAA progression in the absence of lipid lowering. Our results support those studies that suggest that pleiotropic statin effects might be beneficial in AAA, possibly through the upregulation of HO-1. Specific targeted therapies designed to induce HO-1 could become an adjunctive therapeutic strategy for the prevention of AAA disease.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Aortic Aneurysm, Abdominal / drug therapy
  • Aortic Aneurysm, Abdominal / genetics*
  • Aortic Aneurysm, Abdominal / metabolism
  • Aortic Aneurysm, Abdominal / pathology*
  • Body Weight
  • Cytokines / genetics
  • Cytokines / metabolism
  • Disease Models, Animal
  • Disease Progression
  • Enzyme Activation
  • Gene Expression*
  • Genes, Reporter
  • Heme / metabolism
  • Heme / pharmacology
  • Heme Oxygenase-1 / genetics*
  • Heme Oxygenase-1 / metabolism
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors / pharmacology
  • Inflammation Mediators / metabolism
  • Lipids / blood
  • Macrophages / immunology
  • Macrophages / metabolism
  • Macrophages / pathology
  • Male
  • Mice
  • Mice, Knockout
  • Promoter Regions, Genetic
  • Swine

Substances

  • Cytokines
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors
  • Inflammation Mediators
  • Lipids
  • Heme
  • Heme Oxygenase-1