DIFFERENTIAL EFFECTS OF PARAQUAT-INDUCED OXIDATIVE STRESS ON FUNCTIONAL AGING AND LIFESPAN IN MALE AND FEMALE DROSOPHILA MELANOGASTER

Aging is accompanied by loss of motor function that is often linked to oxidative stress. We asked how genotype and sex shape this process by exposing Oregon-R (wild-type) and vestigial (wing-deficient) Drosophila of both sexes to chronic paraquat (0, 10, or 20 mM) and tracking climbing performance from day 5 to 50, alongside survival. Paraquat impaired locomotion in a dose-dependent manner, with effects modified by genotype and sex (four-way ANOVA, all p < 0.001). Under control conditions, behavioral half-life (T50) occurred at 21.4 days in Oregon-R males and 25.7 days in females; vestigial flies declined earlier (males 14.8, females 18.3 days). At 20 mM, T50 fell by ~48–53% across groups. The female advantage persisted at 10 mM but narrowed at 20 mM, especially in vestigial flies. Survival changes mirrored functional decline: the interval between T50 and median lifespan compressed under severe stress (≈18–28 days in controls vs. 8–12 days at 20 mM), and functional-survival coupling was strong (r = 0.87, p < 0.001). Together, these data indicate that oxidative stress accelerates functional aging in patterns shaped by genotype and sex and support climbing performance as a practical predictor of healthspan.