Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Superoxide radical generation from heterocyclic amines

H Maeda1, K Sato, T Akaike

  • 1Department of Microbiology, Kumamoto University School of Medicine, Japan.

Princess Takamatsu Symposia
|January 1, 1995
PubMed
Summary

Cytochrome P-450 reductase and NADPH generate superoxide radicals from heterocyclic amines, with implications for cancer. This study identifies specific heterocyclic amines that are potent generators of these radicals, highlighting their role in carcinogenesis.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Hydroxyl radical production by H2O2 plus Cu,Zn-superoxide dismutase reflects the activity of free copper released from the oxidatively damaged enzyme.

The Journal of biological chemistry·1992
Same author

Effect of cilostazol, a cyclic AMP phosphodiesterase inhibitor, on the proliferation of rat aortic smooth muscle cells in culture.

Journal of cardiovascular pharmacology·1992
Same author

Inhibition of mite protease (Df-protease) with protease inhibitors.

Biochemistry international·1992
Same author

[Pharmacokinetic and clinical studies of cefprozil fine granules in children].

The Japanese journal of antibiotics·1992
Same author

[A case of primary alveolar hypoventilation syndrome with a good response to nocturnal low-flow oxygen inhalation and negative pressure ventilation].

Nihon Kyobu Shikkan Gakkai zasshi·1992
Same author

Microvasculature of normal and hydropic labyrinth.

Scanning microscopy·1992

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Toxicology

Background:

  • Cytochrome P-450 reductase (also known as cytochrome c reductase) is an enzyme crucial for various cellular redox reactions.
  • Heterocyclic amines (HCAs) are compounds found in cooked foods that have been linked to carcinogenesis.
  • Superoxide radicals (O2.-) are reactive oxygen species implicated in cellular damage and disease promotion.

Purpose of the Study:

  • To investigate the generation of superoxide radicals (O2.-) from various heterocyclic amines (HCAs) catalyzed by cytochrome P-450 reductase.
  • To identify specific HCAs that are more potent generators of O2.-.
  • To determine the kinetic parameters (Km values) for HCA metabolism by cytochrome P-450 reductase.

Main Methods:

  • Electron spin resonance (ESR) spectroscopy with spin trapping using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) was employed to detect O2.-.

Related Experiment Videos

  • A panel of 11 different heterocyclic amines were tested for their ability to generate O2.- in the presence of purified cytochrome P-450 reductase and NADPH.
  • Lineweaver-Burk plots were used to calculate Km values for specific HCAs.

    • Main Results:

    • Superoxide radical (O2.-) generation was confirmed from 11 different HCAs.
    • 2-amino-3,4-dimethylimidazo[4,5-f]-quinoline (MeIQ) showed the strongest signal for O2.- generation.
    • The order of O2.- generation potency was MeIQx = IQ > diMeIQx > other HCAs, with MeAαC showing the lowest generation.

    Conclusions:

    • Cytochrome P-450 reductase, in conjunction with NADPH, effectively generates superoxide radicals from various heterocyclic amines.
    • The differential generation of O2.- by HCAs suggests varying levels of oxidative stress and potential carcinogenic risk.
    • These findings have significant implications for understanding the mechanisms of carcinogenesis and tumor promotion, given the known role of oxygen radicals in these processes.