Rosemary Extract-Mediated Lifespan Extension and Attenuated Oxidative Damage in Drosophila melanogaster Fed on High-Fat Diet

Rosemary extract has a potent antioxidant activity and is widely used in the food industry. In this study, the lifespan prolonging and antioxidant activity of rosemary extract was evaluated by high-fat-induced oxidative damage in Drosophila melanogaster. The results revealed that the lifespan and climbing ability of fruit flies was enhanced significantly by feeding rosemary extract. Furthermore, feeding with rosemary extract significantly increased the enzyme activity of superoxide dismutase (SOD) and catalase (CAT), and significantly decreased the level of malonaldehyde. The gene expression of SOD, CAT, and nuclear factor erythroid-2 related factor 2 was enhanced and that for methuselah was significantly reduced. The comet assay showed that high-fat diet-induced DNA lesion was significantly reduced in larvae treated with the rosemary extract. Our results suggest that feeding with rosemary extract is effective to the extended lifespan in fruit flies by strengthening of the resistance to high-fat-induced oxidative stress and by stimulating, at least in part, the endogenous antioxidant response.