Vitamin E acts as a useful chemopreventive agent to reduce spontaneous lung tumorigenesis in mice.
The present study was designed to evaluate whether vitamin E could be a useful chemopreventive agent to reduce spontaneous lung tumorigenesis in mice. Starting at 6 weeks of age, groups were divided into three groups, i.e. A/J mice fed a control diet (A/J control), A/J mice fed a vitamin E-supplemented diet (A/J vitamin E) and ddY mice fed a control diet (ddY control). At the 28th experimental week, nuclear NADPH-driven active oxygen generation, thiobarbituric acid reactive substances (TBARS) and DNA single strand breaks (DNA-SSB) in A/J mice fed a control diet were significantly higher than those in the ddY control group. A/J mice fed Vitamin E for 28 weeks could decrease the levels of TBARS and DNA-SSB with a significant difference, as compared with those in A/J control mice. The nuclear alpha-tocopherol levels in A/J controls were significantly lower than those in ddY controls, on the contrary, the vitamin feeding to A/J mice increased nuclear alpha-tocopherol levels more than that in the ddY controls. At the 40th experimental week, lung tumor incidence and tumor multiplicity (percentage of mice with tumors) in A/J controls were reduced and brought close to those in ddY control mice by vitamin E. Then the alpha-tocopherol level in plasma of A/J controls was significantly lower than the level in plasma of ddY controls, and the level in tumor-bearing mice in A/J controls also showed a lower level with significant difference as compared to that in non-tumor-bearing mice of A/J controls. These results suggest that the difference in susceptibility to spontaneous lung tumorigenesis between A/J and ddY mice partly depends on the difference of oxidative stress on the pulmonary nuclei, and vitamin E can act as a useful chemopreventive agent to reduce spontaneous lung tumorigenesis in mice.
Yano
T
T
Division of Applied Food Research, National Institute of Health and Nutrition, Tokyo, Japan.
Obata
Y
Y
Yano
Y
Y
Otani
S
S
Ichikawa
T
T
D000818:Animals; D015227:Lipid Peroxidation; D008175:Lung Neoplasms / Q000517:prevention & control*; D008297:Male; D051379:Mice; D010100:Oxygen / Q000378:metabolism; D014810:Vitamin E / Q000378:metabolism / Q000494:pharmacology*
D014810:Vitamin E; D010100:Oxygen