Ray Kurzweil reviews the talks given by participants of the Fifth Annual Alcor Conference on Extreme Life Extension.
Robert Freitas is a Research Scientist at Zyvex, a nanotechnology company, and in my view the world's leading pioneer in nanomedicine. He is the author of a book by the same name and the inventor of a number of brilliant conceptual designs for medical nanorobots. In his first major presentation of his pioneering conceptual designs, Freitas began his lecture by lamenting that "natural death is the greatest human catastrophe." The tragedy of medically preventable natural deaths "imposes terrible costs on humanity, including the destruction of vast quantities of human knowledge and human capital." He predicted that "future medical technologies, especially nanomedicine, may permit us first to arrest, and later to reverse, the biological effects of aging and most of the current causes of natural death."
Freitas presented his design for "respirocytes," nanoengineered replacements for red blood cells. Although much smaller than biological red blood cells, an analysis of their functionality demonstrates that augmenting one's blood supply with these high pressure devices would enable a person to sit at the bottom of a pool for four hours, or to perform an Olympic sprint for 12 minutes, without taking a breath. Freitas presented a more complex blueprint for robotic "microbivores," white blood cell replacements that would be hundreds of times faster than normal white blood cells.
Freitas has the full text of his conference lecture entitled "Death Is An Outrage" on his web site.
The end result of all these nanomedical advances will be to enable a process I call “dechronification” – or, “rolling back the clock.” I see no serious ethical problems with this. According to the volitional normative model of disease that is most appropriate for nanomedicine, if you’re physiologically old and don’t want to be, then for you, oldness and aging are a disease, and you deserve to be cured. After all, what’s the use of living many extra hundreds of years in a body that lacks the youthful appearance and vigor that you desire? Dechronification will first arrest biological aging, then reduce your biological age by performing three kinds of procedures on each one of the 4 trillion tissue cells in your body.
* First, a respirocyte- or microbivore-class device will be sent to enter every tissue cell, to remove accumulating metabolic toxins and undegradable material. Afterwards, these toxins will continue to slowly re-accumulate as they have all your life, so you’ll probably need a whole-body cleanout to prevent further aging, maybe once a year.
* Second, chromosome replacement therapy can be used to correct accumulated genetic damage and mutations in every one of your cells. This might also be repeated annually.
* Third, persistent cellular structural damage that the cell cannot repair by itself such as enlarged or disabled mitochondria can be reversed as required, on a cell by cell basis, using cellular repair devices.
We’re still a long way from having complete theoretical designs for many of these machines, but they all appear possible in theory, so eventually we will have good designs for them.
Freitas links to another article of his that further expounds on the coming ability of nanobots to repair bodies and reverse aging:
Artificial "biobots" could be in our bodies within five to 10 years. Advances in genetic engineering are likely to allow us to construct an artificial microbe - a basic cellular chassis - to perform certain functions. These biobots could be designed to produce vitamins, hormones, enzymes or cytokines in which the host body was deficient, or they could be programmed to selectively absorb and break down poisons and toxins. A new company called engeneOS, Inc., founded in late 2000, has already announced plans to develop artificial Engineered Genomic Operating Systems using the techniques of molecular biology. These systems will comprise a library of component device modules and proprietary modular components. This will allow the engineering and construction of programmable biobots with novel form and function.
Unfortunately, Kurzweil says little about Aubrey de Grey's presentation at the conference and yet de Grey is proposing the development of some fairly specific rejuvenation techniques that show a lot of promise. What is important about the techniques that Aubrey advocates is that they can be made to work many years before nanomedicine becomes possible. In fact, Aubrey argues (and I agree), that we know enough now about the molecular mechanisms of aging and that we already have sufficently advanced biochemical tools and techniques to start developing some forms of aging-reversal intervention. The candidate methods of intervention and aging reversal could be tested using the tools that biochemists and molecular biologists already possess and the results of the tests would show how much various interventions may help.
Aubrey also holds the radical view (and is having success in convincing a number of noted biologists on this) that it will be faster to the develop aging reversal therapies to avoid the diseases of old age than it will be to continue to try to develop treatments for those diseases to deal with the disorders of old age once they appear. His argument is that it is the processes of aging that are increasing the incidence of the many disorders of old age and so if we make our bodies younger we will avoid many of the diseases that inflict people as they grow older.
Aubrey has co-authored a paper with a prominent list of biologists (Aubrey D. N. J. de Grey, Bruce N. Ames, Julie K. Andersen, Andrzej Bartke, Judith Campisi, Christopher B. Heward, Roger J. M. McCarter and Gregory Stock) which describes some of the techniques that could be used to reverse aging. The paper is entitled Time to Talk SENS: Critiquing the Immutability of Human Aging.
Aging is a three-stage process: metabolism, damage and pathology. The biochemical processes that sustain life generate toxins as an intrinsic side-effect. These toxins cause damage, of which a small proportion cannot be removed by any endogenous repair process and thus accumulates. This accumulating damage ultimately drives age-related degeneration. Interventions can be designed at all three stages. However, intervention in metabolism can only modestly postpone pathology, because production of toxins is so intrinsic a property of metabolic processes that greatly reducing that production would entail fundamental redesign of those processes. Similarly, intervention in pathology is a "losing battle" if the damage that drives it is accumulating unabated. By contrast, intervention to remove the accumulating damage would sever the link between metabolism and pathology, so has the potential to postpone aging indefinitely. We survey the major categories of such damage and the ways in which, with current or foreseeable biotechnology, they could be reversed. Such ways exist in all cases, implying that indefinite postponement of aging – which we term "engineered negligible senescence" – may be within sight. Given the major demographic consequences if it came about, this possibility merits urgent debate.
The term "negligible senescence" was coined1 to denote the absence of a statistically detectable increase with organismal age in a species’ mortality rate. It is accepted as the best operational definition of the absence of aging, since aging is itself best defined as an increase with time in the organism’s susceptibility to life-threatening challenges. It has been compellingly shown to exist only in one metazoan, Hydra;2 certain cold-blooded vertebrates may exhibit negligible senescence but limitations of sample size leave the question open;1 and it has not been suggested that any warm-blooded animal (homeotherm) does so. Indeed, humans are among the slowest-aging homeotherms.
Since Gilgamesh, civilization has sought to emulate Hydra – to achieve a perpetually youthful physiological state – by intervention to combat the aging process. Such efforts may appropriately be termed "strategies for engineered negligible senescence" (SENS). This phrase makes explicit the inevitable exposure to extrinsic, age-independent causes of death (which is blurred by more populist terms such as "immortality" or "eternal youth"), while also stressing the goal-driven, clinical nature of the task (in contrast to the basic-science tenor of, for example, "interventive biogerontology"). Here we discuss the feasibility, within about a decade, of substantive progress towards that goal.
Click thru and read the full paper. If you don't have college level training in biology it might be a bit hard to follow on some points. But most of it can be understood by the interested layman.
|Share |||Randall Parker, 2002 December 01 10:56 PM Aging Reversal|