Research described as “a major landmark” and “a milestone in the field” restored lost vision in old mice by restoring damaged cells in the eye to a youthful state.
This is the first time any treatment has succeeded in accomplishing this, and to say scientists are excited is an understatement.
The researchers believe one day this new “reprogramming” technique could help turn back time for other parts of the body as well.
Back in July we told you about a remarkable discovery from Juan Carlos Izpisúa Belmonte and his team at the Gene Expression Laboratory at San Diego’s Salk Institute for Biological Studies.
Dying, lifeless mice with a disease of accelerated aging called progeria were rejuvenated; the clock was turned back on all their cells and organs and the mice became lively and active.
Dr. Belmonte was able to turn back time by reprogramming cellular chemical switches called epigenetic markers that turn genes on and off. Changes to the markers from aging cause cells to function less efficiently, and some scientists believe this is the underlying cause of aging.
Restoring Health, Cell by Cell
Dr. Belmonte reset the markers by adding four proteins that occur in some genes. Called Yamanaka factors, they wipe the markers clean. This restores aging cells to a primitive embryonic state called induced pluripotent stem cells (IPSCs).
Trouble is, these cells can’t be controlled. They might develop into a normal cell; then again, they might become a malfunctioning or cancerous cell, which is what occurred in the mice. In fact, many of the mice died within days because they developed tumors or other malfunctions following the treatment.
But that was not the end of the story.
Seeing that creating cellular blank slates was a step too far, Dr. Belmonte and his team devised a procedure to partially reprogram the markers—and they succeeded.
Life Extended By 30 Percent
The mice treated with Dr. Belmonte’s new programming technique did not develop tumors. What’s more, their bodies grew healthy and stayed that way with treatment, extending their lives by 30 percent.
An exciting development, indeed, but this new reprogramming technique still requires far more research. Enter a team of geneticists at Harvard.
Since one of the Yamanaka factors was linked to cancer, the Harvard scientists dropped this gene, combined the other three – which they dubbed OSK – and loaded them into a virus to shuttle them into cells, hoping to restore the cells’ youth and enable them to repair damaged tissue. They also developed a technique to switch OSK “on” and “off” as needed.
Then, they tested their new discovery on mice with injured eye cells. The results were astounding as the treatment regenerated damaged nerves five times over.
Geneticist Yuancheng Lu was blown away by what he witnessed, saying, “It was like a jellyfish growing out through the injury site. It was breathtaking.”
Reversed Vision Loss
In additional experiments with mice, the Harvard scientists were able to reverse vision loss due to both aging and glaucoma– a hereditary eye disease that increases pressure in the eye, damaging the optic nerve and resulting in blindness.
David Sinclair, who led the research, said, “The treatment allowed the nerves to grow back towards the brain. Normally they would simply die.
“I’m excited about being able to rejuvenate organs and tissues that fail due to aging and disease.”
OSK Praised By Experts
“It is a major landmark,” said Dr. Belmonte of the Harvard team’s research. “These results clearly show that tissue regeneration in mammals can be enhanced.”
Andrew Huberman, a neuroscientist at Stanford, called it “a milestone in the field.”
“The effects of OSK in people remain to be tested, but the existing results suggest that OSK is likely to reprogram brain neurons across species.
“For decades, it was argued that understanding normal neural developmental processes would one day lead to the tools to repair the aged or damaged brain… [this] work makes it clear: that era has now arrived.”
Judith Campisi, a cell biologist at the Buck Institute for Research on Aging in Novato, California, is also cautiously optimistic. She notes “There are many labs now who are working on this whole concept of reprogramming.
“We should be hopeful but, like everything else, it (the study) needs to be repeated and it needs to be extended.”
The Harvard researchers agree. They’re already planning a human trial in people with glaucoma. We’ll follow their progress and keep you updated on their findings.