Researchers have shown that a protein they earlier showed can make the failing hearts in aging mice appear more like those of young health mice, similarly improves brain and skeletal muscle function in aging mice.
In two separate papers, Professors Amy Wagers and Lee Rubin, of Harvard's Department of Stem Cell and Regenerative Biology (HSCRB), report that injections of a protein known as GDF11, which is found in humans as well as mice, improved the exercise capability of mice equivalent in age to that of about a 70-year-old human, and also improved the function of the olfactory region of the brains of the older mice - they could detect smell as younger mice do.
Rubin and Wagers each said that, baring unexpected developments, they expect to have GDF11 in initial human clinical trials within three to five years. Postdoctoral fellow Lida Katsimpardi is the lead author on the Rubin group's paper, and postdocs Manisha Sinha and Young Jang are the lead authors on the paper from the Wagers group.
Both studies examined the effect of GDF11 in two ways. First, by using what is called a parabiotic system, in which two mice are surgically joined and the blood of the younger mouse circulates through the older mouse.
And second, by injecting the older mice with GDF11, which in an earlier study by Wagers and Richard Lee, of Brigham and Women's Hospital was shown to be sufficient to reverse characteristics of aging in the heart.
Wagers first began using the parabiotic system in mice 14 years ago as a post doctoral fellow at Stanford University, when she and colleagues Thomas Rando, of Stanford, Irina Conboy, of UC Berkley, and Irving Weissman, of Stanford, observed that the blood of young mice circulating in old mice seemed to have some rejuvenating effects on muscle repair after injury.
The two separate papers have been released online in the journal Science.
