Research into the eternal human aspiration to stay forever young continues to bring forth new meanings for and sources of the elusive fountain of youth. In yet another attempt, scientists have taken a cue from the ubiquitous Fruit Fly to satiate our hunger for evergreen youth.

A new study published in the journal Cell Metabolism, explains how an understanding of the Fruit Fly's intestine has helped researchers explore the impact of minimal diets on longevity. The new finding is seen as a precursor to discovering new clues on the impact of aging on stem cell behavior. The findings also suggest that the Fruit Fly version of a gene known as PCG-1, which is also found in human DNA, could act as a biological guide to slowing down the aging process. A further insight from the study suggests the possibility of exploring and finding targeted drug remedies to counter aging or age-related diseases.

Although it is a well-documented fact that restricting calories during daily food intake is the easiest strategy to extend life spans for both humans and animals, little is known about biological mechanisms underlying this phenomenon.

Previous studies, however, have shown that the cells of calorie-restricted animals have greater numbers of energy-generating structures known as mitochondria. Researchers at the Salk Institute for Biological Studies and from the University of California, Los Angeles, investigated the chain of connections between mitochondria and longevity.

Fruit flies and humans have a lot more in common than most people think, said Leanne Jones, an Associate Professor at Salk's Laboratory of Genetics and a lead scientist on the project, There is a tremendous amount of similarity between a human small intestine and the fruit fly intestine.

The researchers found that boosting the activity of dPGC-1, the Fruit Fly version of the gene, resulted in greater numbers of mitochondria and more energy-production in flies; the same phenomenon is seen in organisms on calorie restricted diets.

When the activity of the gene was accelerated in stem and progenitor cells of the intestine, which serve to replenish intestinal tissues, these cellular changes correspond with better health and longer lifespan.

The flies lived between 20 and 50 percent longer, depending on the method and extent to which the activity of the gene was altered.

Their intestines were beautiful, said Christopher L. Koehler, a doctoral student at the University of California, San Diego, who conducts research in Jones' laboratory, The flies with the modified gene activity were much more active and robust than the other flies.

Scientists theorized that one reason for this could be the boosting of PCG-1 led to stem cells being stimulated to replenishing intestinal tissues, thereby keeping the flies' intestines healthier.

Slowing the aging of a single, important organ, in this case the intestine -- could have a dramatic effect on overall health and longevity, Jones said, In a disease that affects multiple tissues, for instance, you might focus on keeping one organ healthy, and to do that you might be able to utilize PGC-1.

The PCG-1 gene regulates the number of these cellular power plants, which convert sugars and fats from food into energy for cellular functions. Previous studies have confirmed that animals on restricted diets lived more than twice as long, on average, as those on non-restricted diets.