Article thumbnail
Location of Repository

Gamma-tocopherol detoxification of nitrogen dioxide: superiority to alpha-tocopherol.

By R V Cooney, A A Franke, P J Harwood, V Hatch-Pigott, L J Custer and L J Mordan

Abstract

In the vitamin E group, alpha-tocopherol is generally considered to be the most potent antioxidant with the highest vitamin bioactivity, yet gamma-tocopherol is produced in greater amounts by many plants and is the principal tocopherol in the United States diet. This report describes a fundamental difference in the chemical reactivities of alpha-tocopherol and gamma-tocopherol with nitrogen dioxide (NO2), which leads to the formation of a nitrosating agent from alpha-tocopherol, but not from gamma-tocopherol. Nitric oxide (NO) is a major product of the reaction of gamma-tocopherol with NO2, while alpha-tocopherol reacts with NO2 to form an intermediate tocopheroxide analogue. The biological significance of gamma-tocopherol is suggested by limited epidemiological data as well as the observation that it is a more potent inhibitor than alpha-tocopherol of neoplastic transformation during the postinitiation phase in 3-methylcholanthrene-treated C3H/10T1/2 murine fibroblasts. This latter property suggests the superiority of gamma-tocopherol in a mammalian biological assay and a role for endogenous NO production in promotion of neoplastic transformation

Topics: Research Article
Year: 1993
DOI identifier: 10.1073/pnas.90.5.1771
OAI identifier: oai:pubmedcentral.nih.gov:45961
Provided by: PubMed Central
Sorry, our data provider has not provided any external links therefore we are unable to provide a link to the full text.

Suggested articles


To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.