Researchers at Washington University may have found the fountain of youth—without leaving their laboratory. Recent studies indicate increased levels of SIRT1 in the brain may eventually lead to lengthening the average human lifespan. The study’s senior author Shin-ichiro Imai, associate professor of developmental biology and internal medicine at Washington University, says studies have demonstrated SIRT1 is connected to a mechanism that allows animals to survive even when food is scarce. “It’s very significant,” explains Imai. “Imagine if you were to extend lifespan by 50 percent to human beings. If the average life span is 80 years old that means people could live up to 120 years old as an average.”
Diet restriction is the only experimental nutritional method known to help delay aging. Mice engineered to have higher levels of SIRT1 in the brain have increased physical activity and body temperature even under low energy intake. SIRT1 prompts the mice to continue to search for food, even after going hungry for an extended period of time.
After a two-day fast, normal mice huddled in the corner, Imai explains. In another cage, the mice with the increased levels of SIRT1 remained active even without nourishment. “If you sit and wait for food and the food is not readily available you’re going to die, which means you have to look for food," says Imai. "SIRT1 basically increases your level of activity in response to a low nutritional input.” Eventually, raising activity levels of SIRT1 may combat the anorexia of aging and motivate the elderly to remain active.