Attenuation of ischemic inflammatory response in mouse brain using an adenoviral vector to induce overexpression of interleukin-1 receptor antagonist

J Cereb Blood Flow Metab. 1998 Aug;18(8):840-7. doi: 10.1097/00004647-199808000-00004.

Abstract

It has been demonstrated that administration of an interleukin-1 receptor antagonist protein (IL-1ra) reduces ischemic brain injury; however, the detrimental mechanism initiated by interleukin-1 (IL-1) in ischemic brain injury is unclear. In this study, we used mice that were transfected to overexpress human IL-1ra to elucidate the role of IL-1 in the activation of the inflammatory response after middle cerebral artery occlusion (MCAO). Myeloperoxidase (MPO) activity and immunohistostaining were used as a marker of polymorphonuclear leukocytes (PMNL) infiltration. Adenoviral vector (1 x 10(9) particles) was administered by injection into the right lateral ventricle in mice. Five days later, MCAO was performed on the mice using a suture technique. Permanent MCAO was achieved for 24 hours in the Ad.RSVIL-1ra-transfected. Ad.RSVlacZ-transfected, and saline (control) mice. Myeloperoxidase activity was quantified in each region and localization of MPO was determined by immunohistochemistry. After 2 hours of MCAO, the surface cerebral blood flow was reduced to 13.5% +/- 3.4%, 10.75% +/- 2.6%, and 10.9% +/- 2.6% of baseline in the ischemic hemisphere in Ad.RSVIL-1ra-transfected, Ad.RSVlacZ-transfected, and saline-treated mice, respectively. The MPO activity in the ischemic hemisphere in the Ad.RSVlacZ group was similar to that in the saline control group (cortex: 0.40 +/- 0.22 versus 0.33 +/- 0.11; basal ganglia: 0.46 +/- 0.23 versus 0.49 +/- 0.17; P > 0.05); however, it was significantly reduced in the Ad.RSVIL-1ra group (cortex: 0.18 +/- 0.07; basal ganglia: 0.26 +/- 0.15; P < 0.05). Myeloperoxidase immunohistochemistry showed that the massive accumulation of MPO-positive cells in the ischemic cortex, striatum, and corpus callosum regions was greatly attenuated in Ad.RSVIL-1ra-transfected mice. Our results indicate that Ad.RSVIL-1ra-transfected mice provide a useful tool to study the mechanism of action of IL-1. The MPO activity assay and immunostaining after 24 hours of focal ischemia were significantly reduced in IL-1ra gene-transfected mice, suggesting that IL-1 may play an important role in the activation of inflammatory cells during focal cerebral ischemia.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenoviridae
  • Animals
  • Biomarkers
  • Brain / drug effects
  • Brain / immunology*
  • Brain / pathology
  • Brain Ischemia / immunology
  • Brain Ischemia / prevention & control
  • Brain Ischemia / therapy*
  • Gene Transfer Techniques
  • Genetic Therapy*
  • Genetic Vectors
  • Humans
  • Inflammation
  • Interleukin 1 Receptor Antagonist Protein
  • Ischemic Attack, Transient / immunology*
  • Ischemic Attack, Transient / pathology
  • Ischemic Attack, Transient / therapy*
  • Male
  • Mice
  • Neutrophils / immunology
  • Neutrophils / pathology
  • Peroxidase / analysis
  • Receptors, Interleukin-1 / antagonists & inhibitors
  • Recombinant Proteins / biosynthesis
  • Sialoglycoproteins / biosynthesis*

Substances

  • Biomarkers
  • IL1RN protein, human
  • Il1rn protein, mouse
  • Interleukin 1 Receptor Antagonist Protein
  • Receptors, Interleukin-1
  • Recombinant Proteins
  • Sialoglycoproteins
  • Peroxidase