Aging Is Reversible--at Least in Human Cells and Live Mice

Caveats:

1) Doing anything to the aging of cells in culture has next to nothing to do with what goes on inside aging tissues, or where it does that is heavily dependent on the details. The article doesn't tell you enough to decide, so you should look at the paper.

2) Doing anything that attenuates the effects of an accelerated aging phenotype, actually usually a DNA repair disorder, almost always has nothing to do with aging as it happens in normal individuals. You can hit mice with hammers, and then evaluate the effects of a hammer-blocking cage, but that doesn't tell you anything about aging - and for exactly the same reasons. This is generally true except when it is isn't, and that depends on the fine details. Again, go look at the paper.

3) The interesting experiment is the one in which pluripotency-inducing factors are upregulated in a normal mouse. This is the thing that people have looked at in the past and said, well, turning on widespread transformation of somatic cells into pluripotent stem cells sounds like a really bad idea. Cancer seems the likely outcome, but there is also the point that your central nervous system rather relies upon maintaining the fine structure it has established in many cases, such as data stored in the brain. Running in and randomly reprogramming any CNS cells that take up the vector or the pluripotency signals seems like a bad idea on the face of it.

So on the whole it is fascinating that a good outcome was produced in the normal mice, analogous to the sort of thing that has been produced via stem cell transplants and telomerase gene therapies. But I'd still want to see what happens to the mice over the long term after that, and would expect cancer.