Down-regulation of oxidative DNA lesions in human mononuclear cells after antioxidant supplementation correlates to increase of gamma-tocopherol
2008 (English)In: International Journal for Vitamin and Nutrition Research, ISSN 0300-9831, Vol. 78, no 4-5, 183-194 p.Article in journal (Refereed) Published
The protective effect of vitamin E supplements has been questioned, possibly because they often contain only alpha-tocopherol, and recent studies indicate that gamma-tocopherol also has important properties. The aim of this study was to investigate whether the levels of DNA lesions in middle-aged, overweight males could be reduced by consumption of low doses of an antioxidant supplement for six weeks, designed to imitate a balanced diet. The participants (n=60) were randomly divided into: placebo, single-, and double-dose groups. Genotoxic and oxidative DNA lesions in mononuclear cells were measured with the Comet assay, before and after supplement administration. Furthermore, a cell study was performed to investigate if pre-incubation of a human lung cell line (A549) with alpha- and gamma-tocopherol (5 and 50 microM for 23 hours) could protect against induced oxidative DNA lesions as measured by the Comet assay. The level of oxidative DNA lesions in the double-dose group was significantly lower than in the control group. Oxidative DNA lesions correlated only to changes in serum gamma-tocopherol, and not alpha-tocopherol. In the cell study, only gamma-tocopherol protected cells against induced oxidative DNA lesions. We therefore hypothesize that gamma-tocopheol rather than alpha-tocopherol is involved in reducing oxidative DNA lesions.
Place, publisher, year, edition, pages
2008. Vol. 78, no 4-5, 183-194 p.
Tocopherol, vitamin E, oxidative stress, DNA damage, DNA lesions, antioxidant supplements, Comet assay
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-104615DOI: 10.1024/0300-98188.8.131.52ISI: 000264544800003PubMedID: 19326341OAI: oai:DiVA.org:uu-104615DiVA: diva2:219985