The effect of a water-dispersible beta-carotene formulation on the prevention of age-related lymphoid neoplasms in mice.

There is currently a great interest in the efficiency of micronutrients against age-associated disorders. The present study aimed to evaluate the efficacy of beta-carotene on the incidence of lymphoid neoplasia, a fatal pathology associated with OFI mouse ageing. Beta-carotene, given as a water-dispersible preparation to 8-month-old mice, on a four month follow-up study, significantly reduced the incidence of neoplasm (12.5% versus 50% for controls). Evaluation of the parameters of oxidative stress showed a highly-significant reduction of the antioxidant defenses in the liver of cancer mice when compared to healthy controls (78% decrease in GSH-Px activity and 47% decrease of the ratio GSH/GSSG). Liver GSH-Px activity was 35% higher in old than in young mice, which correlated with higher (41%) plasma Se level. In conclusion beta-carotene improved the antioxidant status of the mice, causing a 4.5-fold increase in the liver GSH/GSSG ratio, an effect which was probably responsible for the lowered incidence of neoplasia observed.