Effect of vitamin E on 4-nitroquinoline 1-oxide-induced lung tumorigenesis in mice.
Oxidative stress may play a partial role in chemically induced tumorigenesis in mice. Herein, we investigated the preventive effect of vitamin E on 4-nitroquinoline 1-oxide (4NQO)-induced oxidative damage on pulmonary nuclei and lung tumorigenesis in mice. At 4 weeks after 4NQO injection, the levels of nuclear thiobarbituric acid substances (TBARS) and DNA single strand breaks (DNA-SSB) in the lungs of mice treated with 4NQO were significantly higher than those in the control mice. The 4NQO-induced oxidative stress on the nuclei and DNA-SSB were significantly inhibited by vitamin E treatment. The nuclear alpha-tocopherol level in the 4NQO-treated group was significantly lower than that in the control, but the plasma alpha-tocopherol level in the former was slightly lower than that in the latter. Vitamin E feeding compensated the decrease of the level in the nuclei and plasma. The feeding on excessive vitamin E for 23 weeks after 4NQO injection could partly reduce the lung tumor incidence as well as lung tumor multiplicity in mice. These findings suggest that vitamin E could partly suppress 4NQO-induced lung tumorigenesis in mice, probably through the inhibition of 4NQO-induced oxidative damage on the nuclei.
Yano
T
T
Division of Applied Food Research, National Institute of Health & Nutrition, Tokyo, Japan.
Obata
Y
Y
Ishikawa
G
G
Hagiwara
K
K
Ichikawa
T
T
D015112:4-Nitroquinoline-1-oxide; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D004249:DNA Damage; D008168:Lung / Q000378:metabolism / Q000648:ultrastructure; D008175:Lung Neoplasms / Q000139:chemically induced* / Q000378:metabolism / Q000517:prevention & control*; D008297:Male; D051379:Mice; D018384:Oxidative Stress; D013047:Specific Pathogen-Free Organisms; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014810:Vitamin E / Q000008:administration & dosage / Q000378:metabolism / Q000627:therapeutic use*
D017392:Thiobarbituric Acid Reactive Substances; D014810:Vitamin E; D015112:4-Nitroquinoline-1-oxide