Researchers have found that the blood of young mice has the ability to restore mental capabilities in old mice.
If the same holds true for humans, it could pave way for new treatments for dementias such as Alzheimer’s disease, said researchers from Stanford University School of Medicine.
In the study, published in the journal Nature Medicine, the researchers pinned down numerous important changes in the brains of old mice that shared the blood of young mice. The scientists also tested older mice’s performance on standard laboratory tests of spatial memory after infusions.
“We’ve shown that at least some age-related impairments in brain function are reversible. They’re not final,” said Saul Villeda, study’s lead author and a graduate student at Stanford.
Previous experiments by Tony Wyss-Coray, the senior author of the study and a Stanford professor of neurology and neurological science, Villeda and colleagues had found that key regions in the brains of old mice exposed to blood from young mice produced more new nerve cells..
This time, the researchers checked both for changes within nerve circuits and individual nerve cells and for demonstrable improvements in learning and memory.
They examined pairs of mice whose circulatory systems had been surgically conjoined. Members of such pairs, known as parabiotic mice, share a pooled blood supply.
Researchers found that the hippocampi of older mice that had been conjoined to younger mice more closely resembled those of younger mice than those of paired older mice. They made greater amounts of certain substances that hippocampal cells are known to produce when learning is taking place, for example.
“It was as if these old brains were recharged by young blood,” Wyss-Coray said.
Heat treatment can denature proteins, so this hints that a blood-borne protein, or group of them, may be responsible for the cognitive improvements seen in old mice given young mouse plasma, researchers said. — PTI