Aspirin didn’t pan out. Neither did two other potential anti-aging agents. But a synthetic derivative of a pungent desert shrub is now a front-runner in ongoing experiments to find out if certain chemicals, known to inhibit inflammation, cancer and other destructive processes, can boost the odds of living longer.
A new research paper co-authored by Oklahoma Medical Research Foundation scientist Kenneth Hensley, Ph.D., reports early results from a mouse study being conducted for the National Institute on Aging. The study, now in its fourth year, will test as many as two dozen possible anti-aging agents in animals within the next five years.
The scientists were surprised to find so quickly that one agent showed promise: NDGA, a compound derived from creosote (chaparral) bushes. These common North American desert shrubs have been traditionally used by Native Americans as healing remedies.
The preliminary results, published online in the journal Aging Cell (and appearing in the August print edition), show that male mice fed a normal diet and NDGA so far have survived in significantly greater numbers than mice on a normal diet. Scientists measured the difference at a point called median lifespan, when half the control mice had died of natural causes associated with aging.
No significant difference occurred in female mice. The scientists can’t explain why at this point.
Hensley devised the idea of studying NDGA’s effect on aging after observing that it extended the lives of mice affected by a condition similar to Lou Gehrig’s disease. “Based on those results, we decided to administer it to healthy mice,” said the OMRF researcher. “Not only did the mice tolerate NDGA well, but they appeared younger, healthier and had stronger hind legs than normal mice.”
The large, carefully controlled study is being conducted at three sites and is intended to provide some of the first reliable data on potential drugs to slow aging and its accompanying ills. Hensley says prior studies typically have been too small and their results hard to confirm in subsequent studies.
In six to 10 months, once all the mice in the control group have died, the scientists will get answers to the really burning question: Will the mice fed NDGA, already well past middle age, live past the normal outer limit of old age? The longest that mice of this type usually live is about three years.
Hensley cautions that people should not bulk up on creosote bush leaves as a way to defy old age. If NDGA continues to show promise in the final results of this study, other labs likely will try to duplicate the results in animals. Much more research is needed before any possible human anti-aging drug could emerge, Hensley said.
The Food and Drug Administration doesn’t evaluate the safety of such herbal remedies. But, said Hensley, there have in the past been reports of people dying after drinking tea derived from creosote leaves. “So we need to do a lot more work in the lab before we can even consider trying this in people.”
“Even if this agent turns out to be good for mice, it won’t be possible to tell without careful studies of humans whether NDGA is beneficial, harmful or has no effect whatsoever,” he warned.
The study was led by Richard A. Miller of the University of Michigan, Randy Strong of the University of Texas Health Science Center and David E. Harrison of the Jackson Laboratory in Bar Harbor, Maine. In addition to Hensley’s work at OMRF, the project also includes collaborators at the University of Florida and Milan, Italy.
Results from the study were presented earlier this month at the annual meeting of the American Aging Association. The research is funded by the National Institute on Aging, part of the National Institutes of Health.
About OMRF:
Chartered in 1946, OMRF (www.omrf.org) is an independent, nonprofit biomedical research institute dedicated to understanding and developing more effective treatments for human disease. Its scientists focus on such critical research areas as Alzheimer’s disease, cancer, lupus and cardiovascular disease. OMRF’s scientists, who include a member of the National Academy of Sciences and a Howard Hughes Medical Institute investigator, hold more than 500 U.S. and international patents.
