Aging: a biologically managed process

By | 22 Junie 2009

growingoldIn a research article it was found that in Phuket during the last Tsunami very few homes with resident grandparents  lost children in the flood. The explanation is at the same time complex and simple:   simple, because these older people recognized the strange behavior of the animals and the silence when the birds had left. They immediately insisted that the children run for the mountains and not go and look at the receding tides. Probably also complex because the grandparents instinctively knew what  to do, either from instinct or the wisdom of many years.

It seems that aging is a biologically controlled process.  Judges and lawyers traditionally wear white wigs to give an impression of age with concomitant wisdom, influence and power. The money of the world and the power of economics is in the hands of the hoary headed, and with this comes great influence.

On 19 February 2008, The BBC screened a program on “How to live to 101”. They identified  900 centenarians out of a population of 1 million in Okinawa, Japan,  four times that of the UK population. Dr Bradley Wilcox visited 90 year olds that looked no more than 60.  A 100 year old villager tells us that when death comes calling even at his age “ you say, I have to discuss that with my family”. In Okinawa specifically vegetables and also fruit make an important contribution. They eat plant protein like soy and there is a popular saying of “Eat only to 80% full”.

This story of healthy aging is repeated in Sardinia and the Mediterranean countries.  In California there is a 92 year old cardiothoracic surgeon who performs 4 major open heart operations per week. There they also found a 103 year old woman who cycles 10 km for her customary daily trip. She is a Seventh Day Adventist,  (and,  previously being  resident Physician to the Adventists in Bloemfontein, I can vouch for their common sense healthy living  and  proven extended lifespan).  It is common knowledge that serious churchgoers enjoy a modest longevity advantage.

There is  bad news as well. Whenever Okinawans move abroad they age rapidly due to high fat diets and low levels of exercise;  they become fat, gluttonous and slothful like the rest of the Western world following the so-called Western lifestyle, and they all die quickly. (Darwin has nothing to say on survival of the fattest.)

In the inner city of Glasgow some of the lowest life expectancy figures in Europe are found. People of 47 years need bypass operations, have heart attacks and osteoarthritis of hip and knees as well as cancers. Possibly a sequence of rapid industrialization, epidemics, poor housing and overcrowding selected for a high-level of the inflammatory response which acts as a  genetic survival mechanism in diversity, but rapid aging is the price of childhood survival.

The longevity of mankind is one of our most astonishing successes. In Roman times the average age was less than 30 years and today, in the first world, it is 95 years. The extra years mean that  we who read this paper woke up this morning to what is effectively a 29 hour day. 24 of  those hours will be used today but the other five will be put in stock for later use by yourself. The challenge is to ensure that when we have access to these hours at the end of our lives it should be productive, happy,  useful and  free from high cost.

The study of aging is a relatively new field in medicine. To meet this challenge of productive time at the end of our life requires  good levelheaded research,  not over simplistic but not  overwhelmed by complexity.  An interdisciplinary approach known as ‘systems biology’ (essentially the study  of interactions between components of a biological system) is used.

oldSome scientists have suggested that aging is too complicated for serious scientific study,  or that it is like a slow motion-car crash:   everything just gets wrecked. There are even those who declare rather strangely that “there is no such thing as aging – old age is associated with disease, but does not cause it”.   At the other end of the spectrum are those who see ageing merely in terms of a biological mechanism  –  a simple matter of the erosion of telomeres (the protective structures at the ends of chromosomes), oxidative damage by ‘free radicals’,  or the dysfunction of mitochondria (the energy-generating organelles within the cell ).

The discovery that a single gene mutation causes major increases in lifespan of animals prompted many to believe that the genetic control of ageing lay in the simple altruistic purpose of creating space for progeny. The implication is then that the extension of the age of retirement from 55 years to the current 70 years if it suits the worker,  might have a major influence on the basic process of aging.  We are aware of an enormous range of faults that arises regularly in molecules, tissues and cells, in the DNA and RNA protein damage as well as membrane damage.

Between aging and cancer there is a spectrum,  with each on opposite sides. If cells are damaged too quickly due to an overactive immune system,  aging is accelerated  If slightly abnormal cells are not identified and eliminated quickly enough by the immune system, there is a chance that cancer cells might “slip through the net” and start to proliferate.  The immune system maintains a balance.

I had the privilege of attending a discussion on aging by a young blonde researcher, Dr.Cynthia Kenyon, Ph.D. (also endowed with a beautiful brain, she  worked with a previous Nobel prize winner in basic sciences) who made the first groundbreaking findings to suggest that aging is a controlled process. She was impressed by the fact that a mouse has a lifespan of 2 years but that a bat of the same weight lives for 50 years.

They researched the lifespan of the Caenorhabditis elegans  worm.  She identified a gene labeled  daf-2 which, when modified,  doubled the lifespan, and coupled to other genes prolonged the active life of Caenorhabditis elegans up to 6 times, preventing muscle weakness and loss of elasticity of the skin . These extra years are full of energy and no age related damage is evident in an animal six times the age of others dying from Alzheimer’s, heart failure, Huntington’s Chorea and Parkinsonism (yes, animals suffer from these diseases too!  Flies usually die from heart failure, mice die from neurological deterioration, literally Alzheimer’s disease) .

It is also evident that the dictum what you see in people is what they are, holds true.  If you look old,  you are old.  If your gait alters and you start walking slowly with short steps, it is a better indication of your biological age than many sophisticated evaluations.  The same applies to failing vision.

*** One of the astonishing findings in C.elegans was that a sugar (even natural fructose from fruit) when added to their food annihilated all the age and survival advantages.  Sugar also altered the action of insulin-like-growth-factor-1. (one of the lifestyle hormones which we have discussed previously but will get  back to in due time).   NOTE: fruit should be taken in moderation; vegetables are still the healthy choice.

Flora Maxwell, a successful British actress,  as nearing her nineties and living alone in her London flat after the departure of her grandchildren to Australia. She wrote “ We who are old know that age is more than disability. It is an intense and varied experience almost beyond our  capacity at times, but something to be carried high. If it is a long defeat it is also a victory, meaningful for initiates of time if not for those who have come less far”.  She also wrote “When a new disability arrives,  I look about me to see if death has come, and I call quietly ‘Death, is that you? Are you there?’  And so far disability has answered. ‘ Don’t be silly. It’s me.’

The more we learn of life, the more obvious it is that to follow a prudent lifestyle and do the right things is of utmost importance,  and that is where we can make an enormous contribution to a meaningful life to the fulfillment of all expectations. Health is the most simplistic and the most complex system known to man and involves living and dying.

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