Effects of tocotrienols on life span and protein carbonylation in Caenorhabditis elegans.

To assess the efficiency of tocotrienols against oxidative damage, we have demonstrated in a model-system nematode, Caenorhabditis elegans, that tocotrienol administration reduced the accumulation of protein carbonyl (a good indicator of oxidative damage during aging) and consequently extended the mean life span (LS), but not the maximum LS. Conversely, alpha-tocopherol acetate did not affect these parameters. As a way to evaluate the protective ability of tocotrienols against oxidative stress, the life spans of animals administrated tocotrienols before or after exposure to ultraviolet B-induced oxidative stress were measured. Ultraviolet B irradiation shortened the mean LS of animals, whereas preadministration of tocotrienols recovered the mean LS to that of unirradiated animals. Interestingly, postadministration also extended the mean LS more than that of unirradiated animals, and administration through the LS conferred greater protection. Thus, the administration of tocotrienols to animals results in a reduction of oxidative stress risks. These data indicated that tocotrienols merit further investigation as possible agents for antiaging and oxidative stress prevention. In addition, they suggest that C. elegans will continue to provide provocative clues into the mechanisms of aging.