alexa Effect of ascorbate on the DT-diaphorase-mediated redox cycling of 2-methyl-1,4-naphthoquinone.
Oncology

Oncology

Journal of Cancer Science & Therapy

Author(s): Jarabak R, Jarabak J, Jarabak R, Jarabak J

Abstract Share this page

Abstract Following the two-electron reduction of 2-methyl-1,4-naphthoquinone by rat liver DT-diaphorase (also called NAD(P)H: (quinone acceptor) oxidoreductase, EC 1.6.99.2), the hydroquinone product is slowly autoxidized to the quinone in buffered solutions at pH 7.0. The autoxidation, which generates the superoxide radical (O2-.) and other reactive oxygen species, is the rate-limiting step in the oxidation-reduction (redox) cycling of the quinone. The addition of ascorbate to these reaction mixtures increases the rate of redox cycling. Two mechanisms are proposed to explain this increase: (1) ascorbate reduces the quinone in a one-electron reduction and (2) if Fe(3+)-EDTA is present, ascorbate reduces the metal chelate in a one-electron reduction. Both mechanisms produce O2-. which initiates the free radical chain reaction that results in autoxidation of the hydroquinone. Although ascorbate may be a physiologically important antioxidant under some conditions, the studies reported here show that ascorbate is a prooxidant in the redox cycling of 2-methyl-1,4-naphthoquinone and, as such, could increase the potential toxicity of this quinone. This article was published in Arch Biochem Biophys and referenced in Journal of Cancer Science & Therapy

Relevant Expert PPTs

Relevant Speaker PPTs

Relevant Topics

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

Agri, Food, Aqua and Veterinary Science Journals

Dr. Krish

[email protected]

1-702-714-7001 Extn: 9040

Clinical and Biochemistry Journals

Datta A

[email protected]

1-702-714-7001Extn: 9037

Business & Management Journals

Ronald

[email protected]

1-702-714-7001Extn: 9042

Chemical Engineering and Chemistry Journals

Gabriel Shaw

[email protected]

1-702-714-7001 Extn: 9040

Earth & Environmental Sciences

Katie Wilson

[email protected]

1-702-714-7001Extn: 9042

Engineering Journals

James Franklin

[email protected]

1-702-714-7001Extn: 9042

General Science and Health care Journals

Andrea Jason

[email protected]

1-702-714-7001Extn: 9043

Genetics and Molecular Biology Journals

Anna Melissa

[email protected]

1-702-714-7001 Extn: 9006

Immunology & Microbiology Journals

David Gorantl

[email protected]

1-702-714-7001Extn: 9014

Informatics Journals

Stephanie Skinner

[email protected]

1-702-714-7001Extn: 9039

Material Sciences Journals

Rachle Green

[email protected]

1-702-714-7001Extn: 9039

Mathematics and Physics Journals

Jim Willison

[email protected]

1-702-714-7001 Extn: 9042

Medical Journals

Nimmi Anna

medical[email protected]

1-702-714-7001 Extn: 9038

Neuroscience & Psychology Journals

Nathan T

[email protected]

1-702-714-7001Extn: 9041

Pharmaceutical Sciences Journals

John Behannon

[email protected]

1-702-714-7001Extn: 9007

Social & Political Science Journals

Steve Harry

[email protected]

1-702-714-7001 Extn: 9042

 
© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version
adwords