Longevity of Man - How long can we live?

Longevity ego blogged across the decades! In 1985 I wrote an essay on longevity and anti-ageing science for my first year biology course. In 1994 I updated it with new telomere information and posted it on my website and had it published in “The Sydney Futurian”, the newsletter of the Sydney Futurian Science Fiction Society

Today I did an RSS search on anti-ageing medicine and found Anti-Aging Medicine & Science Blog , and lo and behold, they have my article on longevity linked from the Futurian mirror site as one of their references!

“The Plausible Futures Newsletter focus on large scale social change and the implications of emerging technologies on the world system.” Their lens looks to the Futurian mirror of my article, too.

This is almost enough to persuade me that I should be paid to write.

The least I can do is blog this.

Longevity of Man - How long can we live?

by Ian Woolf

“Man will never be contented until he conquers death.”
- Dr Bernard Strehler, 1977

According to Dr Walton of the CSIRO, an organism’s life generally
falls into the three phases:


1 growth
2 maintenance, and
3 aging.

It has been the desire to remain or return to phase 2 that has kept
Humanity on our millenia-long qquest for immortality. Scientists now
have some understanding of aging and are actively seeking for ways to
prevent or even reverse the process; some of the quite successfully,
and all of them optimistically.

Life-expectancy in Will Shakespeare’s day was only about thirty years.
In England in the 1880’s, just over a century ago, it was less than
forty years of life for the working class majority. In Australia in
1900, it was fifty-one. In Australia now, it is seventy-five for men,
and eighty-one for women,; a rise of three years in the last decade. In
the 1970’s demographers realized that for older people life expectancy
is rising. In 1975 a sixty-five year old man could expect another 13.1
years, in 1983 a man of 65 averaged 14.2 more years, and in 1993 he can
expect 17.2 more years. Researchers think this is probably due to
better education, nutrition and attention to personal health, as well
as availability of medical treatment for fatal conditions. Yet
individuals now in their seventies and eighties were born early this
century and suffered poorer nutrition and living conditions than today.
This implies that given modern high living standards, children growing
mow should survive well into their nineties.

Free radicals are unstable molecules that cause aging according to Dr
Denham Harman. They disrupt cells by robbing electrons from passing
molecules and triggering destructive reactions. They are created by
oxygen processing in the body, or by contact with smoke and smog. Older
cells are packed with them. Anti-oxidants combat free radicals by
making them more stable, and thus preventing them causing damage.
Vitamins C and E, carotene, and lecithin are all anti-oxidants. Dr
Harman says that anti-oxidants increase life expectancy by twenty
percent or more.

Cross-linkage of vital proteins and nuclei acids in and around body
cells causes aging according to Dr Johann Bjorksten. Gradually, with
the assistance of lead, cadmium, aluminium and free radicals, the
proteins are bound into large aggregates which are irreversibly
immobilized, and clog the cells, ultimately destroying them. In 1970 Dr
Bjorksten isolated microenzymes from soil bacteria which penetrate and
breakdown the aggregates allowing them to be excreted safely. A
proposed “youth pill” would contain the microenzymes plus chelating
agents to remove the metals, and antioxidants to prevent further
cross-linkage. Dr Bjorksten predicts 800 year life spans, soon!

A “death-hormone” is triggered at a genetically programmed time says Dr
Denckla. The hormone is secreted by the pituitary gland after
adolescence. The output increases with age, and progressively blocks
the action of a thyroid hormone, vital to metabolism. Dr Denckla has
delayed aging in rats by removing the pituitary and dosing them with
other hormones. A death-hormone neutralizing drug says Dr Denckla,
could add 30 years to human life expectancy. Dr Denckla left research
in 1980 after his funding was cut.

The thymus gland shrinks with age says Dr Goldstein. Thus thymosin,
which it secretes, is reduced in supply, until at eighty years of age,
the gland has vanished altogether and its supply is zero. Thymosin
maintains the immunological system. As thymosin level falls,
susceptibility to disease and cancer mounts rapidly. Thymosin
injections would allow one to age gracefully, disease-free, although it
is uncertain how much life would be extended.

Metabolic toxins accumulate in our blood and slowly poison us according
to Alexis Carrel. Dr Klebanhoff at the Lackland Airforce Medical Centre
has a “total body washout” machine, which siphons off all blood and
replaces it with an oxygen-carrying solution, then drains this and
gives a complete transfusion. Replacement blood would preferably be
from healthy young donors, or have been cleaned of toxins and
infections.

Abusive living wears out organs. Heart and lungs age due to diets high
in fat and insufficient exercise. The same goes for other body organs.
Organs can be replaced either by transplants or by artificial organs.
There are rejection problems to be overcome with transplants, but heart
and cornea transplants are now commonplace. Prosthetic replacement for
organs have developed slowly, but should benefit from the advances in
the new biotechnology revolution.

The Hayflick limit, until recently, put an absolute upper bound on how
long we could live. Every living cell possesses a biological fuse that
“burns down” a little every time the cell divides; in normal cell, each
division brings death closer. The fuse runs out, and there is no more
cell replacement in the body. The average cell can divide 60 or 100
times before this happens. The fuse on cancer cells never runs down,
they are immortal. In 1993 Calvin Harley’s team at Geron, a Californian
biotechnology company have linked the biochemical changes that give
cancer cells immortality to one that regulates ageing. They have
already discovered a compund that makes cancer cells mortal in a test
tube. They have found that cancer cells manufacture an enzyme called
telomerase that rebuilds the cancer cell’s fuse, so that the cell never
gets the instruction to suicide. They have successfully made cancer
cells mortal by inhibiting telomerase. This will lead to control of
hayflick limit in healthy cells, allowing us to control their longevity
without killing the organism with runaway cancerous replication.

If, pessimistically, we can raise the human lifespan by only fifty
percent in this generation, then that still means that you will
probably live at least thirty years past the projected seventy-five
years the insurance companies expect.

With even a thirty year bonus, the leap into hundreds of years is
likely to occur. If you are now 20 years old, you expect to die around
2045 AD. Add thirty years to that, and you live to 2075 AD. How many
years will medical science be able to give you then? In 2075 AD, an
increase of one hundred years would be conservative. So you can live on
to 2175 AD. And where will life-extension sciences be by then? Likely
any population problems will also have been solved.

Life extension technique	Maximum life-extension predicted
Denckla death-hormone inhibitor	thirty years	30
Bjorksten cross-linkage dissolver	seven hundred years	700
Harman anti-oxidants	twenty years	20
Thymosin injection	uncertain	?
“total body washout”	uncertain	?
Prosthetics and transplants	uncertain	?
Cell fuse extension	uncertain	?
Grand total of extra years	850+

Even if this table is over-optimistic, you will probably live a lot
longer than you expect. Possibly long enough for the next
life-extension breakthrough.

“Some people want to achieve immortality through their works or their
descendants. I prefer to achieve immortality by not dying.”
- Woody Allen, ‘Immortalist’ magazine

A good reason to be confident something will come of this research in a
maximum ten years, is that there are so many scientists researching
longevity from many different directions.

“People now living - the more determined ones - may never die at all”
- Robert Anton Wilson, ‘The Illuminati Papers’

References:

New Scientist 1993-1994
Discover (Dec 1984) “Aging, can we slow the inevitable?” by Gina Morris
Sydney Morning Herald (9/3/85) “The Age of Youth” by M. harris and A. Levinson
‘Future Facts’ by Stephen Rosen (pub Heinmann, 1976)
‘Science Fact’ by Frank George (pub Angus & Robertson, 1977)
‘Your next Fifty Years’ by Robert Prehoda (pub Ace, 1979)
‘Can you live to be 100?’ by Dr Woodruff (pun Chatham Square Press, 1977)
‘The Illuminati Papers’ by Robert Anton Wilson (pub Sphere, 1980)
‘A Step Farther Out’ By Dr Jerry Pournelle (Pub Ace, 1980)

About the author: Ian Woolf lives in Sydney, has a degree in Applied Physics, worked as a solar astronomer, software engineer, systems programmer, webmaster, Cisco CCNA tutor, Computational Theory lecturer, and subject coordinator; while changing his career to professional writing and broadcasting. Listen to Ian on the Discovery science show on radio 2SER 107.3Fm Mondays at 9am in Sydney or streaming audio on www.2ser.com, or listen to the Discovery sound archives.

Posted by iwoolf at March 21, 2004 03:51 PM | TrackBack