Brain rejuvenation in old mice via Yamanaka factors

What's the news: Scientists make younger brains in older mice, via Yamanaka epigenetic reprogramming.

Why should we believe it: This news is based on a preprint of a study posted last week. One of the lead researchers on this study was Steve Horvath, a UCLA professor who in 2013 was the first to create an epigenetic aging clock. Interestingly, Horvath today also works as principal investigator at the well funded longevity startup Altos Labs (see this Long Youthspan segment about Altos Labs).

In this study, scientists injected older mice with a gene therapy that included the four Yamanaka factors. The Yamanaka factors are proteins that turn back the clock in cells — a discovery that won the 2006 Nobel Prize in Medicine.

The results of this gene therapy: significantly improved learning, marginal improvement in spatial memory, and younger epigenetic age of brain cells in these old mice.

Why this is a big deal: Yamanaka reprogramming is one of the most promising avenues to body-wide rejuvenation. Only a few weeks ago, we had the breakthrough news that a gene therapy using three of the four Yamanaka factors reversed blindness in monkeys. Which brings up the tantalizing possibility: Yamanaka-based brain rejuvenation in old mice today, and perhaps in old primates tomorrow?