Something in elderly blood is bad for brains. Plasma from old mice or humans worsens cognition and biological indicators of brain health, when infused into young mice. Conversely, plasma from young mice (or humans) rejuvenates old brains.
Much of this research has come from neurobiologist Tony Wyss-Coray’s group at Stanford University, which is pursuing what constituents of blood might be responsible. One previous study identified a protein, which declines with age, that has powerful beneficial effects. That protein can cross from the blood into the brain, but Wyss-Coray wondered how certain molecules contained in blood typically “talk” to the brain. Must they interact with neurons directly, or can they communicate indirectly, through the gateway to the brain, the blood-brain barrier?
To investigate, Wyss-Coray’s team tried a new approach in their latest study, published May 13 in Nature Medicine. “We reasoned that the most obvious way plasma would interact with the brain is through blood vessels,” Wyss-Coray says. “So, we looked at proteins that change with age and had something to do with the vasculature.” One protein that becomes more abundant with age, VCAM1, stood out, and the team showed that it appears to play a pivotal role in the effects of aged blood on the brain. Biological and cognitive measures alike indicated that blocking VCAM1 not only prevents old plasma from damaging young mouse brains but can even reverse deficits in old mice. The work has important implications for age-related cognitive decline and brain diseases. “Cognitive dysfunction in aging is one of our biggest biomedical challenges, and we have no effective medical therapies. None,” says neuroscientist Dena Dubal, of the University of California, San Francisco, who was not involved in the study. “It’s such an important line of investigation; it has tremendous implications.”
Wealthy vampires take note. ;-) To read more, click here.