Jan. 31, 2013 A new study led by researchers at the University of California, Berkeley, represents a major advance in the understanding of the molecular mechanisms behind aging while providing new hope for the development of targeted treatments for age-related degenerative diseases.

Older and fitter? New findings from a UC Berkeley-led study could have implications for the development of treatments for age-related degenerative diseases.

Researchers were able to turn back the molecular clock by infusing the blood stem cells of old mice with a longevity gene and rejuvenating the aged stem cells' regenerative potential. The findings were published online on Jan. 31, in the journal Cell Reports.

The biologists found that SIRT3, one among a class of proteins known as sirtuins, plays an important role in helping aged blood stem cells cope with stress. When they infused the blood stem cells of old mice with SIRT3, the treatment boosted the formation of new blood cells, evidence of a reversal in the age-related decline in the old stem cells' function.

"We already know that sirtuins regulate aging, but our study is really the first one demonstrating that sirtuins can reverse aging-associated degeneration, and I think that's very exciting," said study principal investigator Danica Chen, UC Berkeley assistant professor of nutritional science and toxicology. "This opens the door to potential treatments for age-related degenerative diseases."

Chen noted that over the past 10 to 20 years, there have been breakthroughs in scientists' understanding of aging. Instead of an uncontrolled, random process, aging is now considered highly regulated as development, opening it up to possible manipulation.

"A molecular fountain of youth"

"Studies have already shown that even a single gene mutation can lead to lifespan extension," said Chen. "The question is whether we can understand the process well enough so that we can actually develop a molecular fountain of youth. Can we actually reverse aging? This is something we're hoping to understand and accomplish."

Chen worked with David Scadden, director of the Center for Regenerative Medicine at Massachusetts General Hospital and co-director of the Harvard Stem Cell Institute.

Sirtuins have taken the spotlight in this quest as the importance of this family of proteins to the aging process becomes increasingly clear. Notably, SIRT3 is found in a cell's mitochondria, a cell compartment that helps control growth and death, and previous studies have shown that the SIRT3 gene is activated during calorie restriction, which has been shown to extend lifespan in various species.

Read more:
Longevity Gene: Discovery opens the door to a potential 'molecular fountain of youth'