That our allotted time on this earth is somewhat fleeting has surely not escaped us, especially as we move farther down our life path. Among the animals and plants with which we share our planet, there is inevitable senescence. Even though as one biologist noted, “aging is an unnatural phenomenon [in that] most animals starve or get eaten, and have no chance to age,” aging and death are part of the human natural order. In recent years, however, a building revolution in the science of gerontology has heralded the possibility of life extension. This is leading some to speculate about just what the limits to human life might be; adding another decade or two or even centuries might be possible.
As our knowledge of the biochemistry of aging increases exponentially, it is no surprise that around the globe scientists are discovering hopeful paths that will provide ways to increase human longevity. Meanwhile, biotechnology companies are seeking to bring new products to market—drugs, cells, tissues, and procedures—which they, too, hope will go some way toward extending life as well as bring a profit.
Is death therefore in terminal decline? While the commercial and media hype concerning such a possibility has dismayed some mainstream scientists, others such as Aubrey de Grey have spearheaded efforts to, as he puts it, “cure the disease of aging.” The Methuselah Foundation chairman and biogerontology researcher is not only chasing the dream of immortality; he expects to catch it.
Noting the potential for life extension in his book How to Live Forever or Die Trying, respected Sunday Times journalist Bryan Appleyard reviews much of the current work and comes to a startling conclusion. “Developments in a number of scientific disciplines,” he writes, “suggest that we may soon be able to increase life expectancies . . . to well over a hundred and, perhaps, to over a thousand.”
WAKE-UP CALL
Humankind suffers from a “global trance” concerning aging, de Grey says, and he wants to wake us up. Aging and its associated pathology are not inevitable, he insists. Once we move beyond our fatalistic view of lifespan, de Grey has faith that science will show us how to reprogram our bodies to maintain our cellular systems in a youthful, self-restorative state virtually forever. He believes there are people alive today who need never grow old.
The modern view of aging is being decoupled from calendar time. Instead, aging appears to be the gradual accumulation of cellular damage caused by the byproducts of the biochemistry of life itself. Like other disease, aging and death are now seen as a progression of events that occur because the body fails to repair ongoing metabolic damage; so although time is an important factor, it is the loss of the repair function that leads to disease. Turning back the hands of cellular time and resetting them permanently in youthful self-repair mode is the greater goal in longevity research. This will require further identification of the links between specific genes, their cell maintenance functions, and other interactions between cells, the body, and the environment.
Our emerging understanding will eventually allow humans to reach what de Grey calls “longevity escape velocity” (LEV). This is not to suggest that science is on the cusp of developing the ultimate silver bullet against aging. Rather, just as transfusions and transplants, pacemakers and statin drugs have extended life today—and sanitation, clean water and food, and an application of the germ theory of disease extended human life in an earlier time—so another new age of medicine is on the horizon. Now, de Grey says, we have come to the point where we can begin to retrain the body to retain its natural rejuvenating processes.
Reaching LEV will not happen immediately, of course. We will not suddenly have ways to challenge Methuselah. By the time we can make 100 the normal life span, new innovations will extend it to 200, and so on, effectively leapfrogging expected life span to, well, no end in sight.
http://www.vision.org/visionmedia/article.aspx?id=18195
No comments:
Post a Comment