The interesting question regarding the removal of the human heartbeat is the impact it will have on other bodily systems. Will it extend life by reducing stress on, for example, vulnerable blood vessels in the brain, or will it shorten life by also eliminating the beneficial response to that stress? Researchers are making progress in artificial hearts, so this question will likely be answered at some point over the next few decades: "The search for the perfect artificial heart seems never-ending. After decades of trial and error, surgeons remain stymied in their quest for a machine that does not wear out, break down or cause clots and infections. But Dr. Billy Cohn and Dr. Bud Frazier at the Texas Heart Institute say they have developed a machine that could avoid all that with simple whirling rotors - which means people may soon get a heart that has no beat. Inside the institute's animal research laboratory is an 8-month-old calf with a soft brown coat named Abigail. Cohn and Frazier removed Abigail's heart and replaced it with two centrifugal pumps. ... If you listened to her chest with a stethoscope, you wouldn't hear a heartbeat. If you examined her arteries, there's no pulse. If you hooked her up to an EKG, she'd be flat-lined. ... The pumps spin Abigail's blood and move it through her body. ... The doctors say the continuous-flow pump should last longer than other artificial hearts and cause fewer problems. That's because each side has just one moving part: the constantly whirling rotor. But Cohn says they will still have to convince the world that you don't need a pulse to live. ... We look at all the animals, insects, fish, reptiles and certainly all mammals, and see a pulsatile circulation. And so all the early research and all the early efforts were directed at making pulsatile pumps. ... However, the only reason blood must be pumped rhythmically instead of continuously is the heart tissue itself. ... The pulsatility of the flow is essential for the heart, because it can only get nourishment in between heartbeats. If you remove that from the system, none of the other organs seem to care much."

Link: http://www.npr.org/2011/06/13/137029208/heart-with-no-beat-offers-hope-of-new-lease-on-life

If the level of interest the public has in their gray hair could only be transferred to an interest in practical work to repair aging, how much better off we'd be. Here is more research into the biological causes of loss of hair pigmentation with aging: "Wnt signaling, already known to control many biological processes, between hair follicles and melanocyte stem cells can dictate hair pigmentation. ... We have known for decades that hair follicle stem cells and pigment-producing melanocycte cells collaborate to produce colored hair, but the underlying reasons were unknown. We discovered Wnt signaling is essential for coordinated actions of these two stem cell lineages and critical for hair pigmentation. ... The study suggests the manipulation of Wnt signaling may be a novel strategy for targeting pigmentation such as graying hair. The research study also illustrates a model for tissue regeneration. ... Using genetic mouse models, researchers were able to examine how Wnt signaling pathways enabled both hair follicle stem cells and melanocyte stem cells to work together to generate hair growth and produce hair color. Research also showed the depletion (or inhibition or abnormal) Wnt signaling in hair follicle stem cells not only inhibits hair re-growth but also prevents melanocytes stem cell activation required for producing hair color. The lack of Wnt activation in melanocyte stem cells leads to depigmented or gray hair."

Link: http://www.sciencedaily.com/releases/2011/06/110614115046.htm

"Should we treat aging?" is a rhetorical question here, but sadly it remains a straightforward open question for much of the world - when it is asked, they are quite serious in asking it. People expect there to be good reasons as to why aging should be left as it is, the cause of death for more than 100,000 people each and every day, and scientists restrained from working on therapies of rejuvenation. This is one of the uphill struggles taking place in the patient advocacy community for aging research, that most people don't consider themselves patients exhibiting the symptoms of degenerative aging, have little inclination to do anything about it, and are in fact initially hostile to the whole idea.

Here's an American Scientist article from researcher David Gems that asks the rhetorical question in the title of this post, and answers it for those who don't see things the way we do:

I am a scientist working in the growing field of biogerontology - the biology of aging. The cause of aging remains one of the great unsolved scientific mysteries. Still, the past decade has brought real progress in our understanding, raising the prospect that treatments might one day be feasible. Yet aging is not just another disease. And the prospect of treating aging is extraordinary in terms of the potential impact on the human condition. So, would it be ethical to try to treat it?

...

I argue for the recognition of an imperative to seek treatments that decelerate aging in order to alleviate late-life diseases. But at what point would such an imperative be fulfilled? Although decelerating aging would postpone the illnesses of aging, it would not make them any less awful. This means that achieving decelerated aging would not lessen the imperative. We would only be compelled to decelerate aging further, and then further still. Here the ethical calculus seems to set us inexorably on a road to ever-greater life extension. Could any sane authority ever opt to force others to forego treatment and suffer from avoidable age-related disease? Surely not.

So it is that decelerated aging would force a dilemma upon us. Should we alleviate suffering on a large scale and accept life extension? Or should we allow an immensity of avoidable suffering in order to avoid extending life? To my mind, the only reasonable course is the first. In fact, we should pursue it energetically, and begin to prevent illness as soon as is feasible. If not, we risk the fury of future generations for dithering. As for life extension, we will just have to take that on the chin. If we can prepare for it socially, politically and institutionally, and if we keep birth rates low, we should be able to ensure long, healthier, happier lives for our children and for our children's children.

In reading this, one must understand there there are a great many people in the world whose first, instinctive reaction to extending healthy human life is to reject it. For them, life extension is indeed a bad thing. Various strains of environmentalism are one of the main culprits here: so many minds are poisoned by the false ideas that spread from environmentalist and related Malthusian ideologies: that there are too many people, that people are intrinsically bad, that wealth and longevity are intrinsically bad, that economics is a zero-sum game, and so forth.

There's nothing wrong with liking trees and wild places enough to spend your hard-earned resources on helping to maintain them. But environmentalism has a way of veering off into the worship of death and destruction, a sort of modern penitent movement focused on the mortification of society as a whole. It's so widespread and embedded in our cultures now that even mild-mannered, everyday folk declare their support for shorter and fewer human lives, for abandonment of technologies that improve the quality of human life, and for relinquishment of technological development that will greatly improve life in the future.

In the long run, these are the ideas we must defeat and bury if we are to build the level of understanding and support required to speed the advent of rejuvenation biotechnology.