Lifespan extension by the antioxidant curcumin in Drosophila melanogaster

The interest in health benefits associated with consumption of anti-oxidants has led to investigations examining the possibility that diets rich in anti-oxidants promote lifespan extension. Studies using the standard fruit fly (Drosophila melanogaster) model of longevity have shown that the antioxidants vitamin E and N-acetyl cysteine prolong lifespan. Turmeric is a spice which has been consumed and used for medicinal purposes for many centuries in Asia. Interestingly, turmeric contains the powerful antioxidant, curcumin. To test the hypothesis that dietary curcumin prolongs lifespan, groups of 30 male D. melanogaster were cultured on media containing 1) no additive; 2) 0.5 mg of curcumin/gram of media; 3) 1.0 mg of curumin/gram of media; 4) 1.0μg of the superoxide dismutase inhibitor, disulfiram/gram of media; 5) 10 g of disulfiram/gram of media; 6) 0.5 mg curcumin and 1.0 g disulfiram/ gram of media; 7) 1.0 mg curcumin and 1.0 g disulfiram/ gram of media; 8) 0.5 mg curcumin and 10 g disulfiram/gram of media; or 9) 1.0 mg curcumin and 10 g disulfiram/gram of media. The number of live fruitflies was noted daily and mean lifespan determined for each treatment group. A significant (P≤0.05) increase in mean lifespan was noted only for the fruitflies maintained on 1.0 mg of curcumin/gram of media; this effect was reversed by addition of disulfiram. These results demonstrate that dietary curcumin prolongs lifespan and that this effect is associated with enhanced superoxide dismutase activity.