長期的な酸化脂質摂取が線虫の生殖能力と寿命に与える影響

Abstract

Fatty acids, which are biologically and functionally crucial components of triacylglycerol and phospholipid,are very sensitive to oxygen attack, and subsequently produce substances such as hydroperoxides and aliphaticlong-chain aldehydes. Although these compounds, collectively called oxidized lipids, are known to be toxicto organism, long-term effects of the oxidized lipids uptake upon organism have much to be uncovered. Inthis study, the effects of long-term uptake of oxidized lipids upon fecundity and life-span were analyzed usingmodel organism, Caenorhabditis elegans. Although oxidized lipids showed little effect on fecundity, mean lifespanof the worms were shortened when they were fed with oxidized fatty acids. However, maximum life span was not affected by oxidized lipid indicating the toxic effect of the oxidized lipids were not uniform throughoutthe life cycle; relatively strong in the early stage of life and gradually become weak as aging proceeds. The toxiceffects of oxidized lipids were diminished by addition of anti-oxidative vitamin α-tocopherol. The expressionof anti-oxidative stress enzyme gene, such as superoxide dismutases and catalases, were analyzed by RT-PCR.The expression of these genes were increased upon long-term oxidized lipids exposure. This indicates that antioxidantprotection system indeed responded to the oxidative stress caused by the oxidized lipids.