Activation of cyclooxygenases by H2O2 and t-butylhydroperoxide in aged rat lung

Biotechnol Lett. 2004 Nov;26(21):1665-9. doi: 10.1007/s10529-004-3519-y.

Abstract

The arachidonate cascade is important for the generation of reactive species (RS), and cyclooxygenase (COX) is a key enzyme of this cascade. Tissues of 24-month-old rat lung showed a 2-fold increase in RS, malondialdehyde and thromboxane B2 than those of 6-month-old rat. We found that the effects of 50 microM H2O2 and 200 microM t-butylhydroperoxide (t-BHP) specify on COX activity, and that their effects increased cytosolic COX activity in a concentration-dependent manner (1-50 microM) in 24-month-old rat. Our results suggested that COX activators such as t-BHP and H2O2, which are located in cytosol, are essential for the activation of COX in aged lung.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging / drug effects
  • Aging / metabolism*
  • Animals
  • Dose-Response Relationship, Drug
  • Enzyme Activation / drug effects
  • Hydrogen Peroxide / pharmacology*
  • Lung / drug effects*
  • Lung / enzymology*
  • Male
  • Oxidative Stress / drug effects
  • Oxidative Stress / physiology
  • Prostaglandin-Endoperoxide Synthases / drug effects
  • Prostaglandin-Endoperoxide Synthases / metabolism*
  • Rats
  • Rats, Inbred F344
  • Reactive Oxygen Species / agonists
  • Reactive Oxygen Species / metabolism*
  • tert-Butylhydroperoxide / pharmacology*

Substances

  • Reactive Oxygen Species
  • tert-Butylhydroperoxide
  • Hydrogen Peroxide
  • Prostaglandin-Endoperoxide Synthases