The challenge of aging; Physiology and aging

The following program is produced by the University of Michigan broadcasting service under a grant of aid from the National Educational Television and Radio Center in cooperation with the National Association of educational broadcasters. The challenge of aging today's program physiology and aging. A program from the series human behaviors social and medical research produced by the University of Michigan broadcasting service with special assistance from the National Health Council and the National help for these programs have been developed from interviews with men and women who have the too often unglamorous job of basic research. Research in medicine the physical sciences the social sciences and the behavioral sciences locational you will hear what may seem like strange or unfamiliar sobs. These are the sounds of the participants office his laboratory or his clinic where the interviews were first conducted. You were here today Dr. Steven M. Horvath. Who is head of the department of

physiology at the Lanka now Hospital in Philadelphia and my name is Glenn Philips. My first question addressed to Dr. Horvath was what do physiologist mean by homeo can he says. This just means a very simple way. For. The organism her since it removed itself as a human organism since it removed itself from the environment of the Seas the oceans has had to develop a mechanism by which it maintains an environment similar to that which you see in the ocean within itself. Consequently any change in the internal environment refers to or is indicated as being a change in homeo can Iesus homeo means. Human. Increases means a pattern of internal of change so as the change of the human organism an attempt to maintain a most optimum level of functioning so that

their entire study of the human organism where there is an organism who which is in a state of health or an organism which is in the state of this health namely illness. Here's a study of the degree to which this homeo kinetic mechanism. He is disturbed. By this is probably one of the most naive but at the same time probably one of the biggest questions confronting you as a physiologist. Is old age and illness. In the past I would say I have a reason most people did not become very 0 in terms of chronological years as been due to the fire that illness or disease processes have. Impinged upon the individual to such an extent as to prevent the development of the normal aging process. Aging is an old old. Phenomenon. It starts with the very first moment but they ovum and the

sperm get together at this time that the cell begins to divide. Aging has begun because of the fact that aging occurs at the very first moment of conception. It really means that by the time an individual as a human is born into this world he has gone through an extensive portion of his aging phenomena. He is at the time that he is born a fairly old individual. Some and some people have estimated that approximately two thirds of his total life potential has been expended in the process of developing from a single room to single cells into the complex thing that we call a baby. You saw that if you then consider that aging has begun from this very first moment that the two cells that combine. Then they continue a process of aging really means.

That from the tight moment on until the time that you die there are certain changes occurring in the total individual and in various of his sub portions namely certain organs such as the liver the kidney the spleen the Longs the heart of the brain disorder the central nervous system to be more precise. All of these organs are undergoing a certain degree of change. However the speed at which these changes occur is quite variable. That is in these different organs some organs happen to age much more rapidly than the others. I was a prior mentor example of theirs for instance we may consider the heart itself. The heart of an individual if you look at one portion of it now just say look at the blood vessels which supply. The blood to the heart the coronary arteries. Those blood vessels are all much older than a corresponding set of blood vessels in another part of the body. Most of you are familiar with with feeling your hair your obtaining your pulse you put your

fingers on what we refer to as a radial artery Now if you want to compare the age of the radial artery which is a vessel about the same size as that of one of the two vessels which supply the heart to coronary arteries the relative age of those two vessels is quite different. A vessel in the heart the coronary artery has aged much more rapidly than has the vessel out in this in the wrist. For instance. Rough comparison seems to indicate that the that the age the characteristics of this vessel at the wrist when you are approximately 16 60 years old chronologically speaking. Is equivalent to that which can be seen in the heart vessel in the coronary artery and at an age of approximately 20 chronological years. So therefore. Here you have a beautiful example of the fact that they similar structure namely a blood vessel. Ages at a different rate in

different parts of the body. This of course also applies to to a more complex organs like in the liver and the kidney kidney for instance ages at quite a different rate than those of the. Liver for example a kidney will be showed signs of change. Oh somewhere between 40th and 50th here chronological age. There. Of course the important thing is not the fact that these vessels these various parts of the body age at different rates. The important thing is which ones happen to age most rapidly in a particular individual. It is quite important for one individual to. For instance to have a rapid aging of a central nervous system of the brain. He may have a perfectly normal functioning body but his brain may have aged much more rapidly than his body. Therefore in some respects he is not as well off as someone who may have a perfectly normally aging brain but may have

some deficiency or so are repeated a lot of say in aging how the scales the muscles where you can't move around as fast. That individual still has certain benefits which an individual. With a. Markedly accelerated aging process in the brain might not happen. It would be better in many cases for some of us to feel that some of our periphery is aging faster than is our central nervous system. Hold on could Amanda live. Now this is a very important question I think Mr. Phillips actually probably the most important question anyone can ask. We really don't know how long a man can live. The life span of the human organism can be estimated on a comparative basis with that of lifespans of various kinds of organisms. And on such a system of comparison. Life expose of the human organism is approximately one hundred and fifty

years. This is quite an important statement to make really. We have had individuals who have lived fairly close to that. There are at least. Half a dozen cases in the literature of people who have lived at least two hundred forty seven. In the Russian literature in the recent news which have become has become available to us. We have reports of individuals who live past 150 years. This is of course to be expected because when you say that the average lifespan of an individual is 150 years this means that plus and minus 10 or maybe even 20 years. But I think the important part of this statement of mine about the lifespan of the individual. Lies in the fact that we today consider people to be aged when they have reached the. Chronological age of 65. This is a somewhat ridiculous sort of feeling to have a body aging because this means we consider people to be our

own when they have not even reached the halfway mark as far as their life. It's. A Spanish concern. Now we are getting closer and closer. To the hundred year old 100 year mark as far as life expectancy is concerned. I might well schism those clipboards and I was just going to ask if what is taking place. Well I mean it has to be there's no way to get around it I was going to say what is happening then you're pushing the years of. Really old age just further and further and further up the scale we're becoming more realistic about what old age happens to be. The life expectancy is it is a statistical figure and it's based upon the number of people who are born of the number of people of bar who die it's a semi mortality sort of thing again. It is true for instance today that in India the reveries life expectancy is slightly over 30 years but we must remember that back around the beginning of our own country

here in the seventeen hundreds. Seven to eighteen hundreds. Life expectancy was always also some worked approximately 30 years. We now are increasing life expectancy so that miss most of us can I hope to live on the average somewhere around 70 years again depending somewhat upon whether you're a male or female if you're a female you have a few extra years to live compared to that of a male. But of course from the standpoint of the physiologist this is. Quite a. Small figure even 150 years happens to be pretty smart. There are some plants. And some trees in particular some traders whose life expectancy. Is even today somewhere in the neighborhood of 6000 or a thousand years. This doesn't mean that we don't ever hope to have man reach anything comparable to that age I think many of us would be really amazed to seem great sure of our population

lived to be 100. Or even one hundred twenty five. Although in my own right is my impression because of the advances we are making in medical sciences and our basic understanding of the physiological processes which go on. In the human body as he ages as it ages. We are coming closer and closer to approaching normal life expectancies of a hundred and a hundred plus. I doubt going back to your statement that. Some of our. Citizens and leaders governmental leaders in the early part of our country were 30 32 33. I think I'll never cease to be amazed but probably to young students of history when they find this fact already there. I think certainly Benjamin Franklin was a. Standout this fire's age was concerned you know you split them you can look back today there's a Mr I had an hour and Jeremy was very active

and 83 plus. And he is certainly far beyond the average life expectancy of the human male. Which is somewhere in the neighborhood of 70 years so he's 13 years greater much more welder now than you would normally expect most human males but again you must remember that we're talking about statistics and then raise the life expectancy of 30 or 35 years means that many people died when they were wanted to and quite a few. More sore some people actually died when they were 70 or 80 or even 90 and certainly it was not unusual to fly and even in the good old days many many years ago to find people who live close to be 100. This is not unusual. The point that is occurring now is that we are not having a greater number of people approaching these so-called magical ages of around century. This is just a statistical figure which we're quoting now. Yes but at the point I was making is it today it would be unheard of to have a group

of. A. Young 30 year olds write a constitution or something I could imagine myself I am 31. I could imagine myself writing a constitution to the United States. I mean yeah I could mean well I'm. Depending on who you talk to about matters of this sort. There. Dr. Laman wrote a book recently that had to do with the relative age of which people made their greatest contribution to society. And. It's so although I personally don't believe it because there are just enough exceptions to any statement that you can my on average their greatest contribution to society by scientists at least was made during their relatively earlier periods of life. That is when they were making their contribution and they generally were somewhere between two I will say 30 or 40 years of age. This does not mean they did not continue to make

contributions afterwards but their major contribution probably occurred at a fairly early age. Heavens I hope I have something left. Well I'm sure that this is changing because we now have a greater opportunity for people to continue to develop. It may well be that the next study the doctor laymen are people similar interest to his will show that the average age at which the major contribution is being made is at a somewhat later date. I think this will undoubtedly occur because it takes longer for us to obtain an equivalent education today than was true for people in say 100 to 200 years ago. I don't want to stop you or particularly but time is going fast here as it always seems to. Me but I do want to go back to the physiological research aspects. And also when I want to get onto your particular interest which is stress. But first I'd like to ask this is there a basic difference between the physiology of the male as

opposed to the female which causes her to live longer than the male. This is a question to which we cannot provide a proper answer. It would appear that on the basis of the fact that in many attributes to female is superior to the male. That there must be some factors involved in their basic physiology which caused this difference. Now what these are. I was saying are present and not new into us. We are desperately trying to elucidate the just the cause of these differences because if it turns out that there is a relatively simple. Chemic. Who are all of the simple physiological process involved. In this prolonged geisha of life and other attributes which the female does have. That we may well transfer those over to the male. And therefore we were looking at this sex difference as far as longevity is concerned although I'm sure we would not be interested in

having it change from other aspects I think we will still like to have females being females for other reasons. Funny I thought of that say things you said that I was protecting myself lately. Let's move on to the stress. Particularly. Do older people have more stresses in life and their now and youthful counterparts. They and there certainly are a number of stresses which older people have which are not present to the younger generation of younger people. I don't think I was referring or meant to infer that these were the things which would interest us. Our interest in the physiological response of people has to do with the fact that their ability to respond to a stressful situation may change with the. Alteration in physiological functioning which may or may not occur with aging. It is this particular aspect that is of most interest to us. We

are using a number of stresses. Some of them are psychological stresses some of them are simple nutritional stresses others are stresses such as environmental factors. Actions such as all these things anything which puts a limit on the individual can be considered a stress. In general we try to evaluate the reactions of the human organism and its attempts to make an adjustment which will keep things at a constant keel within itself. We are we attempt to place upon that organism a stress of some sort. Because this brings out. The ability of the organism to respond. This is what we're interested in not so much the fact that he lives. I mean you can have many things to live which have no meaning after if they're just the fact that they're alive. The build the ability of the individual organism to respond is much more important than his ability just to merely survive.

So we are interested in detecting the ways the man or. The. Mad mechanisms which the individual have different ages utilizes in order to maintain this constant internal keel of his so that he doesn't go too far off one end or the other and we are pretty assured that the success for paging individual is one who is most adequately able to respond to these stressful situations in such a way as not to alter his homier kinetic balances to any great extent. There are other factors of course involved in this which we are not at all clear at the moment but experimentally for instance we can show the alterations and. That individual. Can markedly influence his life expectancy. Not his lifespan but his life expectancy. For instance there have been some very beautiful experiments carried out showing that you

can. In case of an animal like a rat for instance not a rat is not of course similar to a human but there you can do things with rats which you can't do with humans in terms of studying their aging processes. For instance or rats not on the life expectancy is somewhat around two years. Now if you can by some means or rather extend this life expectancy saving to three years which is a tremendous increase in life expectancy then you've really done something. So one of a most interesting experiments which have been conducted in the last 10 years has had to do actually with the anthro and sort of rawest attritional States upon the ability of the experimenter to prolong the life expectancy or to approach extended. I can very easily unwrap and certain other species also. Almost doubles the life expectancy. We can fry some sort of the rock let's

say lives around 700 some on the day. Ordinarily we can get rats to live up to fifteen hundred or sixteen hundred days which is a double of our life. Expectancy this course means that we don't know what the lifespan of the rat is but are again on the basis of the same predictive mechanisms that we employed in predicting the lifespan of a human to be one hundred fifty three. We ordinarily some would say that the life expectancy span of a rat is somewhat over. Four years somewhere between three and a half in four years. Well by the changing his nutritional state. We can increases life expectancy until almost approaches his theoretical lifespan and we did this by a relatively simple sort of procedure. Why we do. Basically although the right is not very happy here and living this long under this system but I would do is reduce the number of calories that he ingests to make sure that he has all the vitamins he needs and all the minerals that he needs but will

reduce his calories to about one half. How those words are normally given to a rat who has his friend who has free choice as to how much he wants to eat by the simple relatively very simple expedient make it all over his food is a logical processes to such an extent that his life expectancy is nearly doubled. Compared to what it had been. There are other possible facets involved in nutritional studies too which offers a logical course in nature. Which would do the same sort of thing. We don't know all these we're just sort of now beginning to approach the problem of aging to the physiological standpoint we're now beginning to think of what are the facets involved in the regulation of this internal environment which would prolonging man's life expectancy but not at the expense of just making him live longer but I think more importantly I think split with the idea in mind that we would make him live as an effective individual for a longer period of time.

One of my old teachers Dr. Chris Saunders once made that very important comment which has become a sort of a guideline. To our journey to logical research. The statement is approximately as follows. This is how our day our goal is not to add years to life but to add life to yours. The implication of the statement is that the mere fact that you can continue. To expand the life expectancy. Is itself not enough. What you must. Have in addition to increasing the life expectancy just increased ability of the individual to function at a higher plane than most of our older people not function for a longer period of time. It's ridiculous to have somebody live to be 100 years of age if he spends the last 35

years in battle. So that we don't want individual do that so the other aspect of physiological research has to do. With mechanisms to maintain the level of efficiency the level of comfort form and so the individual. At. The point. Where he will be performing in such a way that he will not be a drain either upon himself or upon the society within this in which he lives. So we are definitely after. A dream going away but I think a dream which can be accomplished. Making the life worth something to be here on this magical in the age of 65 75 or even 80. We like the city and the individuals who do survive 200 years of age or even longer to be as active physically and mentally as is consistent with their physiological. Status. And this we think we can improve considerably because of our increased knowledge of the ways in which the human

organism. Behaves in response to various stresses facetiously if these rats prove. To be telling the true story is going to play heck but eating. A lot of desserts isn't it. Well basically of course we know that one of our major problems today among all of the American people has to do with the fact that so darn many of them are overweight. And they're overweight because they simply don't have anything else to do except to eat. And it may well be worthwhile to consider the fact that you could benefit considerably by reducing your intake or some of the nonessentials to wife namely the excess of calories which we take in in terms of proteins our desserts and our ice cream and some other concoctions which we delightfully make. I think there's been enough indication in the last two years to make a case. That this is a problem which plagues not only our younger people but also plays older people.

The insurance. Companies are always making this very strong statement that your life expectancy. Can be considerably reduced by being overweight. And that if you're really smart about this to think that you would want to do this to bring your weight down. I think there's a great deal to do learn yet about the physiological changes which occur in the human organism with advancing age. We are just beginning to scratch the surface. One of these days. Well we will never find a magical compound or a magical formula for increasing life expectancy expectancy to this proverbial hundred fifty. I think we will come to the point that by understanding the normal physiological process sees We will pretty soon be able to bring about a radical change in the pattern of living out of the human race so that it will manage to survive. Effectively and usefully even until an age of 100 or

200 plus. This is that eventually the goal of all physiologists. I'm practical about the Basically more importantly of all biologists since aging is a universal phenomenon not limited only to the human organism. Prior knowledge that we will gain from the study of various forms of life. Will be. Handed. Down compounded by our interests in the field of physiological human research and one of these days all of this will come together and we will have attained a understanding of the physiological basis of aging. I certainly appreciate this opportunity Mr. Phillips of talking to you about physiology of aging and I trust that someday you and I can get together and speak more vigorously. So the one thing you know I would have to worry about of course and that we should really live to be about three or 400 years old Judging by our size that.

Some people would even say that. There are many methods suggested you know that we ought to try certain phenomena like hibernation which would keep us alive for a longer period of time reduce our activities you know our thanks to Dr. Steven M. horrifying who is head of the department of physiology at the like in our hospital in Philadelphia for his participation on this program physiology and aging. Next week you will hear Dr. Nathan W. Shoppe who is chief of the Gerontology branch of Baltimore City hospitals in Baltimore Maryland as he discusses research in aging on the next program from the series human behavior social and medical research. We extend our special thanks to the National Health Council and the National Health Forum for their assistance. Glenn Phillips speaking asking that you join us next week and thanking you all for being with us at this time.

This program has been produced by the University of Michigan broadcasting service under a grant in aid from the National Educational Television and Radio Center in cooperation with the National Association of educational broadcasters. This is the NEA E.B. Radio Network.