PROTEIN OXIDATIVE DAMAGE IS ASSOCIATED WITH LIFE EXPECTANCY OF HOUSEFLIES

The objective of this study was to test some of the predictions of the oxidative-stress hypothesis of aging, which postulates that aging is causally associated with the molecular damage inflicted by reactive ox ygen species. Protein carbonyl content was used as an index of molecul ar oxidative modifications. The carbonyl content was found to be assoc iated with the physiological age or life expectancy of flies rather th an with their chronological age. Exposure of flies to sublethal hypero xia (100% oxygen) irreversibly enhanced the carbonyl content of the fl ies and decreased their rate of oxygen consumption. Results of this st udy indicate that protein carbonyl content may be a biomarker of aging and support the general concept that oxidative stress may be a causal factor in the aging process.