Aging and Regenerative Medicine
scientists begin to understand the age-imposed decline in
the regenerative capacity of stem cells (Conboy, Yousef,
and Conboy 2011).
These advances in regenerative medicine raise a host
of ethical, legal, and social questions that health-care
providers, scientists, and policymakers will need to
consider. These questions and concerns include definitions, source materials, appropriate applications, potential risks, and accessibility, as well as the impact on the
environment and social structures (Glenn and Boyce
2012).
AGING AND LONGEVITY
Regenerative medicine, by definition of the National
Institute of Biomedical Imaging and Bioengineering, is “a
rapidly growing multidisciplinary field involving the life,
physical and engineering sciences that seeks to develop
functional cell, tissue, and organ substitutes to repair,
replace or enhance biological function that has been lost
due to congenital abnormalities, injury, disease, or aging”
(US Department of Health and Human Services 2005, 3).
While the search for the “fountain of youth” has long been
considered merely a fantasy, advances in regenerative
medicine and biogerontology in the twenty-first century
suggest that “the aspiration to modify the biological
processes of ageing in humans—and thus delay the onset
of all age-related disadvantages, as well as compress
morbidity and mortality—may actually be achievable”
(Farrelly 2010, 385). Although it has been demonstrated
that human cells’ ability to divide is limited to
approximately fifty times, after which they simply stop
dividing (known as the Hayflick limit theory of aging),
research on the restoration of telomeres to the end of their
chromosomes has shown that the changes associated with
aging can be slowed down or even reversed (Jin 2010).
The debilitating lack of organ maintenance in the old
could be ameliorated and, perhaps, even reversed, as
28
While humanity has always been preoccupied with
discovering the “fountain of youth,” advances in the field
of biogerontology and regenerative medicine hold the
promise of enabling scientists to regenerate damaged
tissues and organs in vitro or in vivo, developing therapies
for previously untreatable diseases and conditions,
combating rising health-care costs, solving the shortage
of transplantable organs, and offering improved quality of
life for an aging population (Glenn and Boyce 2012).
Where some see only benefit in the ability to slow, stop, or
even reverse the aging process, others have argued that
aging is inevitable and have warned that extending
longevity could lead to undesirable consequences, such
as social upheaval and a straining of limited resources
(Hayflick 2000).
AGING AS A DISEASE
The question of intervening in the aging process depends
on whether or not aging is seen as a disease. The medical
profession has not yet come to a consensus about treating
aging as a disease, but opinions are in a state of flux.
ETHICS, SCIENCE, TECHNOLOGY, AND ENGINEERING, 2ND EDITION
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AGING AND REGENERATIVE
MEDICINE
In the Stone Age and throughout much of the history of
humanity, human life expectancy, without the intervention of modern medicine, is estimated to have been
around 20 to 34 years (Bostrom and Roache 2007). As of
2012, in the United States, people who survive to age 65
can expect to live an average of 19.2 more years, nearly 5
years longer than people age 65 in 1960. In 2009 the life
expectancy of people who survive to age 85 was 7 years for
women and 5.9 years for men (Federal Interagency Forum
2012). These statistics reflect that there has been almost a
tripling of life expectancy for humans in the last few
thousand years. This gain is primarily the result of social
and technological developments, such as sanitation,
medicine, education, and nutrition (Bostrom and Roach
2007). The trend in extending longevity will continue;
insurance companies have started banking on the notion
that the first person to live to 150 years of age is now alive
(Prudential 2013).
Aging and Regenerative Medicine
According to the Merriam-Webster online medical
dictionary (2013), a disease is
4
an impairment of the normal state of the living
animal or plant body or one of its parts that
interrupts or modifies the performance of the vital
functions, is typically manifested by distinguishing
signs and symptoms, and is a response to
environmental factors (as malnutrition, industrial
hazards, or climate), to specific infective agents (as
worms, bacteria, or viruses), to inherent defects of
the organism (as genetic anomalies), or to
combinations of these factors.
At first blush, this definition would certainly cover most
symptoms and impairments that result from the process of
aging; pathological changes and morbid processes are
generally the criteria used in determining age in autopsies
or when obtaining a medical history is impracticable
(Caplan 2005). The common risk factor for two major
causes of death worldwide, cancer and cardiovascular
disease, are age; postpone aging, and one postpones these
diseases (Bourzac 2012).
Yet there are those who argue that “ageing is not a
disease because it is not a dysfunction” (Schramme 2013,
182). That is, to explain further, functions are relative to
age, so processes that are functional earlier in life (e.g.,
reproductive ability) are not necessarily functional later in
life. Others argue that because aging is “natural”—or
“inevitable” and “universal”—there should not be intervention; but viral infections, gingivitis, acne, hypertension, and tooth decay are all of those things, but they
warrant intervention. Considering the arbitrariness of
these criteria, it is not intrinsically wrong to try to reverse
or cure aging (Caplan 2005).
At least one author argues that a new model of disease
has emerged based on numerical deviations rather than
symptoms and that it arose in concert with the
development and use of safe, effective, marketable, and
highly profitable prescription drugs (Greene 2007). This
suggests that if treating aging as a disease is profitable, then
aging will be treated as a disease because of market forces.
RESEARCH AND ETHICAL CONSIDERATIONS
Source Materials. One of the primary ethical conundrums
in using regenerative medicine is the source of the stem
cells that are used. Adult stem cells, which have been
identified in many organs and tissues, including brain,
bone marrow, peripheral blood, blood vessels, skeletal
muscle, skin, teeth, heart, gut, liver, ovarian epithelium,
and testis, do not pose an ethical challenge; but even
though they are pluripotent, they are somewhat limited in
their capacity to differentiate. Embryonic stem cells, by
contrast, are totipotent—able to differentiate into any cell
in the body. Embryonic stem cells are controversial
because of differing beliefs regarding the moral status of
embryos. Those opposed to human embryonic stem cell
(hESC) research believe that the fertilized egg has the
moral rights of personhood and that the destruction of
blastocysts devalues human life and dignity (Glenn and
Boyce 2012).
In the center of the spectrum of beliefs are people who do
not object to the use of existing (or future) frozen blastocysts
that are destined to be destroyed, rather than used for
reproductive purposes, to derive new hESCs for research, but
they do not want new blastocysts created specifically for
experimentation. The current policy in both the United States
and Canada is that the federal government will pay only for
research conducted with stem cells harvested from leftover
embryos developed via in vitro fertilization procedures, and
only with the donors’ consent (Glenn and Boyce 2012).
To avoid this ethical controversy, researchers have
found ways of creating induced pluripotent cells (iPCs),
which are adult or midrange stem cells (such as those found
in umbilical cord blood or menstrual blood) that have been
used to successfully reprogram skin cells to behave like
hESCs (Chan and Harris 2008). The area of iPC research is
attractive for several reasons, including the following: first,
it does not require the gathering and use of human eggs;
second, it is genuinely gender neutral because it does not
impose a disproportionate burden on one gender over the
other, in terms of the risks and burdens of egg collection/
donation (Glenn and Boyce 2012).
Therapy versus Enhancement versus Altering Human
Nature. One of the more controversial areas of research
within the field of regenerative medicine involves brain
implants—namely, the potential not only for brain repair or
axon regeneration but also for the merger of artificial
intelligence with human capabilities (Acey 2013). The
ethical, legal, and societal concern is that merging humans
with technology would change what it means to be
“human” or a “person” and change basic human nature
(Glenn 2003). Although technologies often start out for
therapeutic use, use for enhancement often follows. Brain
implants that create interfaces between human neural
systems and computers would allow for (1) the improvement and augmentation of human capabilities; (2) the
advent of “human” immortality through cloning and the
implantation of bioelectronic chips with the uploaded
emotions, memories, and knowledge of the source human;
and (3) the possibility that humanity may be replaced by the
next stage in guided evolution (Glenn and Boyce 2012).
Access. With a widespread aging population, regenerative
medicine will be in peak demand in the decades to come.
As the American Medical Association notes, equal access
to health care is also an ethical issue:
ETHICS, SCIENCE, TECHNOLOGY, AND ENGINEERING, 2ND EDITION
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Aging and Regenerative Medicine
Most Americans understand this: 72 percent think
our society should ensure universal access to
health care, and 60 percent consider it to be a
moral rather than a strictly political or economic
issue. We hold that three core American values are
at stake: equality of opportunity, justice, and
compassion.
Caplan, Arthur L. 2005. “Death as an Unnatural Process: Why Is
It Wrong to Seek a Cure for Ageing?” EMBO Reports 6 (supp.
1): S72–S75.
Equality of opportunity is essential for each of us
to fulfill the American promise of life, liberty, and
the pursuit of happiness, and personal health is an
essential ingredient to ensure opportunity. (Levine
et al. 2007, 15)
Cibelli, Jose, Robert P. Lanza, Keith H. S. Campbell, and Michael
D. West, eds. 2002. Principles of Cloning. Amsterdam:
Academic Press.
The implementation of the Patient Protection
and Affordable Care Act of 2010 shows some promise
of significant gains in coverage and access to basic
care for populations in need, but the promise is
tempered with concerns about enrollment coverage
and sustainability. Only time will tell if regenerative
medicine will become standard or a luxury of only a
privileged few.
Biotech Ethics; Medical Ethics; Posthumanism;
President’s Council on Bioethics.
SEE ALSO
BIBLIOGRAPHY
Acey, Madeleine. 2013. “Brain Implants: Restoring Memory with
a Microchip.” CNN, May 8. http://www.cnn.com/2013/05/
07/tech/brain-memory-implants-humans
Binstock, Robert H. 2003. “The War on ‘Anti-aging Medicine.’”
Gerontologist 43 (1): 4–14.
A scholarly analysis of how mainstream biogerontologists are
countering the practitioners of antiaging medicine who biogerontologists believe are exploiting the public’s ignorance of the science for
financial gain.
Bostrom, Nick, and Rebecca Roache. 2007. “Human Enhancement: Ethical Issues in Human Enhancement.” In New
Waves in Applied Ethics, edited by Jesper Ryberg, Thomas
Petersen, and Clark Wolf, 120–152. New York: Palgrave
Macmillan.
30
Chan, Sarah, and John Harris. 2008. “Adam’s Fibroblast? The
(Pluri)potential of iPCs.” Journal of Medical Ethics 34 (2):
64–66.
Conboy, Irina M., Hanadie Yousef, and Michael J. Conboy.
2011. “Embryonic Anti-aging Niche.” Aging (Albany, NY) 3
(5): 555–563.
Farrelly, Colin. 2010. “Equality and the Duty to Retard Human
Ageing.” Bioethics 24 (8): 384–394.
Federal Interagency Forum on Aging-Related Statistics. 2012.
“Health Status.” http://www.agingstats.gov/Main_Site/Data/
2012_Documents/Health_Status.aspx
Glenn, Linda MacDonald. 2003. “Biotechnology at the Margins
of Personhood: An Evolving Legal Paradigm.” Journal of
Evolution and Technology 13: 35–37.
Glenn, Linda MacDonald, and Jeanann S. Boyce. 2012.
“Regenerative Nanomedicine: Ethical, Legal, and Social
Issues.” In Nanotechnology in Regenerative Medicine, edited by
Melba Navarro and Josep A. Planell, 303–316. New York:
Humana Press/Springer.
Greene, Jeremy A. 2007. Prescribing by Numbers: Drugs and the
Definition of Disease. Baltimore: Johns Hopkins University
Press.
Gruman, Gerald J. 2003. A History of Ideas about the Prolongation
of Life. New York: Springer.
First published 1966 by the American Philosophical Society. Probably the
best history ever written on the evolution of human thought about longevity
from the first written records until 1800.
Hall, Stephen S. 2003. Merchants of Immortality: Chasing
the Dream of Human Life Extension. Boston: Houghton
Mifflin.
Developments in the fields of research on aging, stem cells, regenerative
medicine, and cloning are considered in this well-written and carefully
researched history of these fields. Biological advances, political positions,
and ethical debates are covered in detail.
Hayflick, Leonard. 1994. How and Why We Age. New York:
Ballantine Books.
An overview of the aging process written for the lay reader with a chapter
on the probability and desirability of intervention.
Hayflick, Leonard. 2000. “The Future of Ageing.” Nature 408
(6809): 267–269.
Hayflick, Leonard. 2001. “A Brief History of Cell Substrates
Used for the Preparation of Human Biologicals.” In
Developments in Biologicals, vol. 106, Evolving Scientific and
Regulatory Perspectives on Cell Substrates for Vaccine
Development, edited by Fred Brown, Andrew M. Lewis Jr.,
Keith Peden, and Philip Krause, 5–23. Basel, Switzerland:
Karger.
Hayflick, Leonard. 2004. “Aging: The Reality; ‘Anti-aging’ Is an
Oxymoron.” Journal of Gerontology A 59 (6): B573–B578.
ETHICS, SCIENCE, TECHNOLOGY, AND ENGINEERING, 2ND EDITION
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The same report notes that to be successful, the
contents and limits of health-care benefits must be
established through an ethical process and the health-care
system must be sustainable. To ensure fairness and equity
in coverage decisions, the practical application of the
following principles would be useful: transparency,
participation (of stakeholders), equitableness and consistency, sensitivity to value, and compassion. While this
would be ideal, many questions remain unresolved: Will
regenerative medicine be available only to a privileged few
who can afford it? Can health care be comprehensive and
include regenerative medicine, while at the same time
being equitable and sustainable? Is individual responsibility and accountability incompatible with sensitivity to
value and compassion?
Bourzac, Katherine. 2012. “Interventions: Live Long and
Prosper.” Nature 492 (7427): S18–S20.
The failure to define common terms in the field of gerontology has
contributed to the many conceptual misunderstandings that have hindered
progress and contributed to serious communication failures.
Hayflick, Leonard, Stanley Plotkin, and Robert E. Stevenson.
1987. “History of the Acceptance of Human Diploid Cell
Strains as Substrates for Human Virus Vaccine Manufacture.”
Development of Specifications for Biotechnology Standards 68
(1987): 9–17.
—
Details how the struggle to have normal human fetal cells used for the
production of many of the world’s human virus vaccines was ultimately
won. The early use of primary monkey kidney cells for this purpose revealed
contamination with several dangerous viruses. Yet it took more than a
decade to overcome the scientific, political, and economic resistance to have
them replaced with the safe, normal, human fetal cell strain WI-38
discovered by Leonard Hayflick. Many safe and efficacious vaccines made
in Hayflick’s human fetal cells have since been administered to almost one
billion people.
Jin, Kunlin. 2010. “Modern Biological Theories of Aging.” Aging
and Disease 1 (2): 72–74. http://www.ncbi.nlm.nih.gov/pmc/
articles/PMC2995895/
Levine, Mark A., Matthew K. Wynia, Paul M. Schyve, J.
Russell Teagarden, David A. Fleming, Sharon King
Donohue, Ron J. Anderson, James Sabin, and Ezekiel J.
Emanuel, for the Ethical Force Program. 2007. “Improving
Access to Health Care: A Consensus Ethical Framework to
Guide Proposals for Reform.” Hastings Center Report 37 (5):
14–19.
Merriam Webster. 2013. “Disease.” Accessed September 1. http://
www.merriam-webster.com/medical/disease
Olshansky, S. Jay, Leonard Hayflick, and Bruce A. Carnes. 2002.
“No Truth to the Fountain of Youth.” Scientific American 286
(6): 92–95.
’
’
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A declaration with much supporting evidence that, in the early
twenty-first century, there is no way of intervening in the fundamental
aging process in humans. Signed by fifty-one of the world’s leading
researchers on aging.
Patient Protection and Affordable Care Act of 2010, Pub. L.
No. 111-148, §2702, 124 Stat. 119 (2010). http://www
.gpo.gov/fdsys/pkg/PLAW-111publ148/pdf/PLAW111publ148.pdf
Prudential. 2013. “New Prudential Ad Debuts during Super Bowl:
Ad’s Live Experiment Highlights the Financial Challenges of
Living Longer.” News release, January 31. http://news.
prudential.com/article_display.cfm?article_
id=6490
Schramme, Thomas. 2013. “‘I Hope That I Get Old before I
Die’: Ageing and the Concept of Disease.” Theoretical Medicine
and Bioethics 34 (3): 171–187.
World Health Organization. 2012. “Defining Disease Types I, II,
and III.” http://www.who.int/phi/3-background_cewg_agenda_
item5_disease_types_final.pdf
U.S. Department of Health and Human Services (DHHS). 2005.
2020: A New Vision—A Future for Regenerative Medicine.
Washington, DC: DHHS. http://www.scribd.com/doc/
37338866/2020-A-New-Vision-a-Future-for-RegenerativeMedicine
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“
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Linda MacDonald Glenn
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