Polyethylene glycol-conjugated superoxide dismutase and catalase reduce ischemic brain injury.

Abstract

Superoxide dismutase and catalase enzymatically scavenge superoxide and hydrogen peroxide, respectively. Conjugation of polyethylene glycol to superoxide dismutase (PEG-SOD) or catalase (PEG-CAT) prolongs the circulatory half-life of the native enzymes and enhances their intracellular access. We studied the protective effect of these free radical scavengers on ischemic brain injury using a rat model of focal cerebral ischemia, which is suitable for therapeutic trials. Intravenous administration of PEG-SOD (10,000 U/kg) and PEG-CAT (10,000 U/kg) before ischemia reduced the infarct volume (treatment, 139 +/- 9 mm3, means +/- SE, N = 38; placebo, 182 +/- 8 mm3, n = 37, P less than 0.002). This finding supports the concept that superoxide and hydrogen peroxide contribute to brain injury following focal cerebral ischemia.

• Authors: T H Liu, J S Beckman, B A Freeman, E L Hogan, C Y Hsu
• Journal: The American journal of physiology (Am J Physiol) Vol. 256 Issue 2 Pt 2 Pg. H589-93 (Feb 1989) ISSN: 0002-9513 [Print] United States
• PMID: 2492771 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• catalase-polyethylene glycol
• Carbon Dioxide
• Polyethylene Glycols
• Catalase
• Superoxide Dismutase
• polyethylene glycol-superoxide dismutase
• Oxygen

Topics

• Animals
• Blood Pressure (drug effects)
• Carbon Dioxide (blood)
• Carotid Arteries (physiology)
• Catalase (therapeutic use)
• Cerebrovascular Circulation
• Heart Rate (drug effects)
• Ischemic Attack, Transient (drug therapy, pathology, physiopathology)
• Male
• Oxygen (blood)
• Partial Pressure
• Polyethylene Glycols (therapeutic use)
• Rats
• Reference Values
• Superoxide Dismutase (therapeutic use)