When those mice died some six months later, they still had good eyesight, Sinclair told an audience at Life Itself, a health and wellness event presented in partnership with CNN.
“It’s a permanent reset, as far as we can tell, and we think it may be a universal process that could be applied across the body to reset our age,” said Sinclair, who has spent the last 20 years studying ways to reverse the ravages of time.
“If we reverse aging, these diseases should not happen. We have the technology today to be able to go into your hundreds without worrying about getting cancer in your 70s, heart disease in your 80s and Alzheimer’s in your 90s. This is the world that is coming. It’s literally a question of when and for most of us, it’s going to happen in our lifetimes,” Sinclair told the audience.
While modern medicine addresses sickness, it doesn’t address the underlying cause, “which for most diseases, is aging itself,” Sinclair said. “We know that when we reverse the age of an organ like the brain in a mouse, the diseases of aging then go away. Memory comes back; there is no more dementia.
“I believe that in the future, delaying and reversing aging will be the best way to treat the diseases that plague most of us.”
A reset button
In Sinclair’s lab, two mice sit side by side. One is the picture of youth, the other gray and feeble. Yet they are brother and sister, born from the same litter — only one has been genetically altered to age faster.
However, adult cells fully switched back to stem cells via Yamanaka factors lose their identity. They forget they are blood, heart and skin cells, making them perfect for rebirth as “cell du jour,” but lousy at rejuvenation. You don’t want Brad Pitt in “The Curious Case of Benjamin Button” to become a baby all at once; you want him to age backward while still remembering who he is.
But there was a downside in all this research: In certain situations, the altered mice developed cancerous tumors.
Looking for a safer alternative, Sinclair lab geneticist Yuancheng Lu chose three of the four factors and genetically added them to a harmless virus. The virus was designed to deliver the rejuvenating Yamanaka factors to damaged retinal ganglion cells at the back of an aged mouse’s eye. After injecting the virus into the eye, the pluripotent genes were then switched on by feeding the mouse an antibiotic.
“The antibiotic is just a tool. It could be any chemical really, just a way to be sure the three genes are switched on,” Sinclair said. “Normally they are only on in very young developing embryos and then turn off as we age.”
Amazingly, damaged neurons in the eyes of mice injected with the three cells rejuvenated, even growing new axons, or projections from the eye into the brain. Since that original study, Sinclair said his lab has reversed aging in the muscles and brains of mice and is now working on rejuvenating a mouse’s entire body.
“Somehow the cells know the body can reset itself, and they still know which genes…
Read More: The ‘Benjamin Button’ effect: Scientists can reverse aging in mice. The goal is