Young blood rejuvenates older animals, studies show

Three new medical studies show young blood may be able to improve lives.

Researchers took old mice and gave them blood, and blood proteins, from young mice. They found the old mice showed improved muscle and brain function. The older animals ran faster and longer on a treadmill, had an increased rate of new brain cell creation, were more sensitive to changes in smell and improved on age-related memory tasks.

The studies were conducted at Harvard University, University of California, San Francisco and Stanford University and published in the publications Science and Nature Medicine.

"It was something -- a cross between vampire and Frankenstein where they took two animals and they hooked their blood supply for four weeks called parabiosis," CBS News medical contributor Dr. David Agus explained on "CBS This Morning."

"It was an experiment that was originally done in the '50s that showed mice seem to reverse aging. Now we know the mechanism. So three separate groups showed this. When you hook the blood together, after four weeks, the stem cells in the brain and the muscle and heart, they get activated and turn back on. And in fact, the young mice age and old mice reverse age. Very powerful. Their brain works better, they were able to get through a maze better. Their muscles work better. So certainly very exciting findings."

Scientists hope these mouse studies will lead to anti-aging treatments for humans.

Looking forward to clinical trial research on humans -- which researchers say will begin this year -- the hope is that the particular protein will be identified so researchers won't need all of the blood from the young person, Agus said.

"So the dream is, instead of treating the disease, we actually change you so you're not aging and you can actually, hopefully even reverse it," Agus said. "It has enormous implications for people with disease and people as they grow older."

Though the implications for humans based on this animal study are unknown, Agus said, "there clearly is something here."

He added, "These are the best science journals with really well done science, but it will take a while before we understand how to control it and use it appropriately and safely in humans."