The science of aging has been making headlines this summer. In the same week in July the Washington Post ran the story “Cutting Calories Might Extend Life - For Monkeys, At Least” and the front page of the New York Times reported “Antibiotic Delayed Aging in Experiments with Mice.”
MPrize competitor Dr. Richard Weindruch, University of Wisconsin, is a team leader in the ongoing research that shows monkeys live longer when fed a healthy diet with 30% lower calories. Calorie Restriction has already been shown to extend life in mice; Dr. Stephen Spindler, University of California Riverside, won the Methuselah Foundation Rejuvenation MPrize for the longest living mouse as a result of late life (19 months) intervention. Richard has been studying aging for over 30 years, “I have witnessed a significant increase in the number of labs working on aging related research; from 15 - 20 across the United States to hundreds today.”
Three of those labs are working with the antibiotic touted in the other headline grabbing story, rapamycin. This is significant because it is the first drug to be proven to extend life in mice. The result of a collaboration between teams at the University of Texas, the University of Michigan and Jackson Laboratory, Maine and sponsored by the National Institute on Aging, the study produced significant results in rejuvenation. The mice were given rapamycin, also known as sirolimus, at an advanced age. The study was published on July 8 in the journal Nature.
Rapamycin is generally used as an immunosuppressant for transplant patients. [Read more about transplants in
“Student Contributes to the Future of Organ Replacement” in this newsletter.] It was discovered in Easter Island soil samples about 40 years ago. The researchers were prompted to study its effects on aging after noting that the compound appeared to affect cell growth in lab animals in much the same way as calorie restriction.
The three test sites worked with nearly 2,000 genetically similar mice. The trials began when the mice were about 600 days old, equivalent to 60 year old humans. Rapamycin delayed the deaths of the longest-lived male mice by 101 days and the longest-lived female mice by 151 days. That is similar to 13 human years. Or, when you take into account the average remaining lifespan when the treatment began it is an increase of 38% in female mice and 28% in males.
How rapamycin works remains unclear. It may impact cellular efficiency with the result of delaying aging and preserving good health. The results do not show that the drug prevented any single disease, the mice died of various causes, but they do show that aging was slowed.
These studies and the fascinating range of research now being conducted by the MPrize competitors indicate that there will be lots more headlines - and progress - in the months and years ahead.
