Fruit Fly Research Gives an Answer to Aging?

Fruit flies on dietary restriction need to be physically active in order to reap the lifespan extending benefits that come from their simple diet. If this same principle holds true in humans, those who restrict calories in their diets need to make sure that they eat enough to avoid fatigue.

Research from the Buck Institute shows that flies on dietary restriction shift their metabolism towards increasing fatty acid synthesis and breakdown, specifically in muscle tissue. "Dietary restriction is known to enhance spontaneous movement in a variety of species including primates, however this is the first examination of whether enhanced physical activity is necessary for its beneficial effects," Buck faculty Pankaj Kapahi, PhD, who runs the lab where the research took place, was quoted as saying. "This study establishes a link between DR-mediated metabolic activity in muscle, increased movement and the benefits derived from restricting nutrients." Flies on DR who could not move or had inhibited fat metabolism in their muscle did not demonstrate an extended lifespan. "Our work argues that simply restricting nutrients without physical activity may not be beneficial in humans," Kapahi was quoted as saying.

Additionally, the research points towards a potential target that could produce a drug that mimics the good effects of dietary restriction. Flies that are genetically engineered to overexpress the circulating peptide AKH (the fly equivalent of glucagon in mammals) showed increased fat metabolism, spontaneous activity and extended lifespan even though their diet was unrestricted. AKH plays an important role in glucose and lipid metabolism. "Our data suggests that DR may induce changes in muscle similar to those observed under endurance exercise and that molecules like AKH could serve as potential mimetics for DR that enhance activity and healthspan," lead author, Subhash D. Katewa, PhD, Buck Institute staff scientist, was quoted as saying.

"A better understanding of the dynamics of fat metabolism is needed in order to clarify its role in aging and disease," Katewa was quoted as saying. "These current results suggest that enhanced fat metabolism could help slow aging and the onset of age-related disease."