An aging-related cell surface NADH oxidase (arNOX) generates superoxide and is inhibited by coenzyme Q.

Abstract

This report describes a novel ECTO-NOX protein with an oscillating activity having a period length of ca. 26 min encountered with buffy coat fractions and sera of aged individuals (70-100 years) that generates superoxide as measured by the reduction of ferricytochrome c. The oscillating, age-related reduction of ferricytochrome c is sensitive to superoxide dismutase, is inhibited by coenzyme Q and is reduced or absent from sera of younger individuals (20-40 years). An oscillating activity with a regular period length is a defining characteristic of ECTO-NOX proteins (a group of cell surface oxidases with enzymatic activities that oscillate). The period length of ca. 26 min is longer than the period length of 24 min for the usual constitutive (CNOX) ECTO-NOX proteins of the cell surface and sera which neither generate superoxide nor reduce ferricytochrome c. The aging-related ECTO-NOX protein (arNOX) provides a mechanism to transmit cell surface oxidative changes to surrounding cells and circulating lipoproteins potentially important to atherogenesis. Additionally, the findings provide a rational basis for the use of dietary coenzyme Q to retard aging-related arterial lesions.

• Authors: Dorothy M Morré, Fenghui Guo, D James Morré
• Journal: Molecular and cellular biochemistry (Mol Cell Biochem) Vol. 254 Issue 1-2 Pg. 101-9 (Dec 2003) ISSN: 0300-8177 [Print] Netherlands
• PMID: 14674687 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Multienzyme Complexes
• Superoxides
• Ubiquinone
• Cytochromes c
• Superoxide Dismutase
• NADH oxidase
• NADH, NADPH Oxidoreductases
• Cytochrome Reductases
• Endopeptidase K
• Oxygen

Topics

• Adult
• Age Factors
• Aged
• Aged, 80 and over
• Aging
• Cell Membrane (enzymology)
• Cytochrome Reductases (chemistry)
• Cytochromes c (chemistry)
• Endopeptidase K (chemistry)
• Humans
• Kinetics
• Middle Aged
• Multienzyme Complexes (chemistry, physiology)
• NADH, NADPH Oxidoreductases (chemistry, physiology)
• Oscillometry
• Oxidative Stress
• Oxygen (metabolism)
• Superoxide Dismutase (chemistry)
• Superoxides (chemistry)
• Time Factors
• Ubiquinone (pharmacology)