A study in mice shows that if you kill off aging, poorly-functioning cells in mice, the mice become healthier, more attractive, and more fun to be around. This is obviously the key to human immortality — as long as it doesn't kill us.
USA Today reports on the research, originally published in Nature. Scientists used a genetic tracer to find "senescent" cells — those that were no longer working right as a result of age. Then they used a drug to activate a "suicide gene" in these cells, making them die instead of sticking around. Result, according to Dr. Gary Kennedy, who read the research: "When they blocked the senescent cell process in mice prone to premature aging, they blocked the development of spinal arthritis, the loss of muscle, thinning of skin — they were all reversed. Mice that should have looked prematurely aged were essentially normal." The mice were also more active than usual. The treatment was most effective when it started at birth, but it also worked to some degree when started after the mice began to age.
Obviously, this is the Fountain of Youth. There's just one teensy little problem. Says Dr. Julian Sage, "The tricky part in people will be how many senescent cells you can eliminate without killing the person." There's no mention of whether any mice died as a result of the treatment, but researchers would presumably have to be quite careful when applying the technique to humans — you can't just go triggering a "suicide gene" all willy-nilly. It's also hard to study mouse personality, so it's not clear whether killing off all their old cells drove them crazy, or made them all vain and prissy, or caused the little mouse-portraits in their attics to age in their stead.
Clearing Out 'Old Cells' May Make For A Healthier Old Age [USA Today]