News on Reliability Theory of Aging and Longevity

See also:
-- 'Books Forum' blog
-- 'Health Studies' blog


Greetings,

Here are some excerpts from the a new interview, which is just published by the scientific journal Rejuvenation Research:

Rejuvenation Research, 2009, 12(5): 371-374.
http://www.liebertonline.com/doi/abs/10.1089/rej.2009.0979
back-up copy:
http://health-studies.org/pdf/Interview-RR-2009.pdf

The excerpts are provided in their original, non-edited form, as they were initially presented before the publication.

Any comments and suggestions are welcome!

Please feel free to post your comments and suggestions below by clicking here.

-- Leonid Gavrilov

---------------------------------
-- Leonid Gavrilov, Ph.D. , GSA Fellow
Center on Aging, NORC/University of Chicago
Website: http://longevity-science.org/
Blog: http://longevity-science.blogspot.com/
Our books: http://longevity-science.org/Books.html

---------------------------------------------------

Excerpts from Interview

Question:

3. You have spearheaded the application of reliability theory to the modeling of aging and mortality. Reliability theory is designed to describe the behavior of man-made machines, which differ from living organisms in that they do not incorporate significant in-built self-repair machinery. To what extent do you feel that this difference diminishes the applicability of reliability theory to living organisms?


Answer:

Thank you for your kind comment on our 'spearheading' . Yes, we first started to apply reliability theory to the problem of biological aging more than 30 years ago, as early as in 1978 [1, 2], and since that time the reliability theory of aging and longevity has become well known in scientific literature [3 - 9]. To answer your question on applicability of reliability theory to living organisms, it is useful to consider separately two different topics: (1) applicability of reliability theory as a general concept; and (2) applicability of our particular mathematical models based on reliability theory.

Discussing the first topic, it is important to note that reliability theory is a general theory about systems failure. It allows researchers to predict the age-related failure kinetics for a system of given architecture (reliability structure) and given reliability of its components. Although historically it was initially applied to describe the behavior of man-made machines, nothing in this general mathematical theory prevents us from taking into account the in-built self-repair machinery, if this is needed. Therefore, there are no fundamental problems with applicability of reliability theory to living organisms, as there are no problems in applicability of mathematics in general to living organisms.

Discussing the second topic, it was our initial intent to find the most simple explanation for the major facts about aging and mortality (the very origin of aging, the Gompertz law of mortality, the compensation law of mortality, and the late-life mortality deceleration). We were interested in understanding the first principles and fundamental explanations of aging, before trying to create a comprehensive model, which takes into account all the complexities of living organisms. Therefore, in our models we were focused on accumulation of un-repaired damage as the final outcome of the damage-vs-repair process, leading to age-related decrease in systems redundancy (e.g. decrease in numbers of functional cells).

Now, when these intentionally simplified models with minimum number of assumptions gave us some general understanding of the nature of aging process and mortality laws, the way is opened to build upon them a more detailed and complex model of aging. This work is opened to everyone who can find a protected time to do it.

Another interesting feature of biological systems is that they are formed in evolution during a severe struggle for survival, and biological arms race with numerous infections and predators. Therefore they have many potentially harmful defense mechanisms, which may be useful for short-term survival in hostile wild environment, but not conductive for longevity in a protected environment (like the inflammation response).

So the analogy between living organisms and man-made machines is more appropriate for a man-made military machines, overloaded by weaponry and ammunition at the expense of their durability. Such machines could last much longer in protected environment if many dangerous fighting devices are removed from them.

The same is true for living organisms -- loss of some functions through introduced mutations or other interventions often leads to increased species longevity in a protected environment. Sometimes this observation is interpreted as a proof that aging is a programmed process, while in fact it simply means that organisms were selected by Nature for survival in the wild hostile environment, rather than for longevity in protected laboratory conditions.


References

1. Gavrilov, L.A. A mathematical model of the aging of animals. Proc. Acad. Sci. USSR [Doklady Akademii Nauk SSSR], 1978, 238(2): 490-492. English translation by Plenum Publ Corp: pp.53-55. PMID 624242

2. Gavrilov, L.A., Gavrilova, N.S., Yaguzhinsky, L.S. The main regularities of animal aging and death viewed in terms of reliability theory. J. General Biology [Zhurnal Obschey Biologii], 1978, 39(5): 734-742. PMID 716614

3. Gavrilov LA, Gavrilova NS. Reliability Theory of Aging and Longevity. In: Masoro E.J. & Austad S.N.. (eds.): Handbook of the Biology of Aging, Sixth Edition. Academic Press. San Diego, CA, USA, 2006, 3-42. ISBN 0-12-088387-2

4. Gavrilov LA, Gavrilova NS. Models of Systems Failure in Aging. In: P Michael Conn (Editor): Handbook of Models for Human Aging, Burlington, MA : Elsevier Academic Press, 2006. 45-68. ISBN 0-12-369391-8.

5. Gavrilov LA, Gavrilova NS. Why We Fall Apart. Engineering's Reliability Theory Explains Human Aging. IEEE Spectrum, 2004, 41(9): 30-35.

6. Gavrilov LA, Gavrilova NS. The Reliability-Engineering Approach to the Problem of Biological Aging. Annals of the New York Academy of Sciences, 2004, 1019: 509-512. PMID 15247076

7. Gavrilov L.A., Gavrilova N.S. The quest for a general theory of aging and longevity. Science's SAGE KE (Science of Aging Knowledge Environment) for 16 July 2003; Vol. 2003, No. 28, 1-10. http://sageke.sciencemag.org , PMID 12867663

8. Gavrilov L.A., Gavrilova N.S. The reliability theory of aging and longevity. Journal of Theoretical Biology, 2001, 213(4): 527-545. PMID 11742523

9. Gavrilov L.A., Gavrilova N.S (1991), The Biology of Life Span: A Quantitative Approach. New York: Harwood Academic Publisher, ISBN 3-7186-4983-7

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Key words:
Reliability Theory of Aging and Longevity, Rejuvenation Research, Reliability Theory of Aging, Interview, Reliability Theory, , Leonid Gavrilov, Natalia Gavrilova, ageing, aging, gerontology, longevity, repair, mortality laws, the origin of aging, the Gompertz law of mortality, the compensation law of mortality, the late-life mortality deceleration


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New Interview on Aging and Longevity Studies

See also:
-- 'Books Forum' blog
-- 'Health Studies' blog


Greetings,

This is to invite you to comment here on new interview on aging and longevity studies, published recently by the 'Rejuvenation Research' journal:

Rejuvenation Research, 2009, 12(5): 371-374.
http://www.liebertonline.com/doi/abs/10.1089/rej.2009.0979
and:
http://health-studies.org/pdf/Interview-RR-2009.pdf

Any comments and suggestions are welcome!

Please feel free to post your comments and suggestions below by clicking here.

-- Leonid Gavrilov

---------------------------------
-- Leonid Gavrilov, Ph.D. , GSA Fellow
Center on Aging, NORC/University of Chicago
Website: http://longevity-science.org/
Blog: http://longevity-science.blogspot.com/
Our books: http://longevity-science.org/Books.html

P.S.:
Also, here are some excerpts from this published interview (original non-edited text):

1. How, in general, can demographers contribute to the effort to develop medical treatments to combat aging?

There are several ways how human population studies could be very useful for efforts to extend healthy life span.

First, there is an area of biodemography - a science, which integrates biological knowledge with demographic approaches in attempt to understand the dynamics of vital events in human populations, including mortality and longevity [1-4]. Looking back at the history of science we can see that such important health findings as the discovery of long-term harmful effects of smoking, hypertension, high cholesterol levels and hyperglycemia all came from statistical (epidemiological) studies on human populations. These significant findings from population studies served as a guide and justification for subsequent development of specific medical treatments and health policies already saving many human lives now.

Looking forward at the future of biodemographic studies, we anticipate 'unraveling the secrets of human longevity' -- the discovery of determinants for exceptional human survival, which allow some individuals to delay dramatically many diseases of aging, and to live a remarkably healthy long life (sometimes beyond 100 years). When we find out why some people are so resilient to aging, these findings could serve as a guide and justification for development of new medical treatments and health policies to combat aging. To make this happen we developed a new research project 'Biodemography of Exceptional Longevity', which was recently awarded a grant from the U.S. National Institute on Aging, NIA. Information about the progress of this research project is continually updated at our scientific website 'Unraveling the secrets of human longevity' ( http://longevity-science.org/ ), and it is opened for comments and public discussion at our blog 'Longevity Science' ( http://longevity-science.blogspot.com/ ). Some preliminary findings on this topic are already published [5-7].

Second, there is an area of traditional demography, which has tools to make demographic projections for different scenarios of life extension. This is an important issue, because a common objection against starting a large-scale biomedical war on aging is the fear of catastrophic population consequences (overpopulation). This fear is only exacerbated by the fact that no detailed demographic projections for radical life extension scenario were published so far. What would happen with population numbers if aging-related deaths are significantly postponed or even eliminated? Is it possible to have a sustainable population dynamics in a future hypothetical non-aging society? These are important questions, which could be answered through traditional demographic studies.

Recently we made a new study, which explores different demographic scenarios and population projections, in order to clarify what could be the demographic consequences of a successful biomedical war on aging. The results of this study supported by the Methuselah and SENS foundations were presented at the SENS4 conference in Cambridge, UK, this September, and are expected to be published [8]. In brief, we found that defeating aging, the joy of parenting and sustainable population size are not mutually exclusive. This is an important point, because it can change the current public perception that life-extension necessarily leads to overpopulation. Amazingly, when we were returning back to the USA from the SENS4 conference in England, the passport control officer asked us exactly the same question about overpopulation during the interview about the purpose of our international travel! This example indicates how deep is the penetration of overpopulation scare in the fabrics of modern society, and hence how important are the demographic studies on this topic.

References

1. Curtsinger JW, Gavrilova NS, Gavrilov LA. Biodemography of Aging and Age-Specific Mortality in Drosophila melanogaster. In: Masoro E.J. & Austad S.N.. (eds.): Handbook of the Biology of Aging, Sixth Edition. Academic Press. San Diego, CA, USA, 2006, 261-288.

2. Gavrilov L.A., Gavrilova N.S., Olshansky S.J., Carnes B.A. Genealogical data and biodemography of human longevity. Social Biology, 2002, 49(3-4): 160-173.

3. Gavrilov, L.A., Gavrilova, N.S. Biodemographic study of familial determinants of human longevity. Population: An English Selection, 2001, 13(1): 197-222.

4. Gavrilova, N.S., Gavrilov, L.A. Data resources for biodemographic studies on familial clustering of human longevity. Demographic Research [Online], 1999, vol.1(4): 1-48. Available: http://www.demographic-research.org/Volumes/Vol1/4/

5. Gavrilova N.S., Gavrilov L.A. Can exceptional longevity be predicted? Contingencies [Journal of the American Academy of Actuaries], 2008, July/August issue, pp. 82-88.

6. Gavrilova N.S., Gavrilov L.A. Physical and Socioeconomic Characteristics at Young Age as Predictors of Survival to 100: A Study of a New Historical Data Resource (U.S. WWI Draft Cards). Living to 100 and Beyond: Survival at Advanced Ages [online monograph]. The Society of Actuaries, 2008, 23 pages.

7. Gavrilova N.S., Gavrilov L.A. Search for Predictors of Exceptional Human Longevity: Using Computerized Genealogies and Internet Resources for Human Longevity Studies. North American Actuarial Journal, 2007, 11(1): 49-67.

8. Gavrilov L.A., Gavrilova N.S. Demographic Consequences of Defeating Aging. [Meeting Abstract]. Rejuvenation Research, 2009, 12( Suppl. 1): 29-30.

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Key words:
Rejuvenation Research, Interview, Overpopulation, Reliability Theory, Predictors of Exceptional Longevity, Leonid Gavrilov, Natalia Gavrilova, ageing, aging, gerontology, longevity, centenarians, parental age


Home:
Longevity Science Blog
and
New Interview on Aging and Longevity Studies
Shorter weblink:
http://tinyurl.com/ydpnvhe


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