Aging: The Loss of Temporal Organization

Publisher Website
Google Scholar
Abstract
AGING: THE LOSS OF TEMPORAL ORGANIZATION H. V. SAMIS, JR.* Aging, I am sure, has concerned man since first he realized that it happens to him. Since then he has attempted to avoid it, reverse it, and, to some degree, understand it. None ofthese efforts has thus far met with much success. By and large, aging is thought ofin terms ofthe psychological , economic, social, and medical problems which it generates; it is thought of as being what it seems to create—especially what it seems to create in man. In my view, however, aging isfirst a biological problem because it isfirst a biological phenomenon. Biological organisms suffer a gradual decline in functional potential with advancing age. This decline is essentially linear and is accompanied by an exponentially increasing probability of death [i]. These senescent changes are manifest so dramatically that even the untrained eye does not confuse a man of sixty with a man of twenty-five. Nevertheless, little progress has been made in uncovering the causes or cause for these changes which so distinctly mark senescence in the biome. The notion that common effects arise from common causes, although intuitively derived, is one of the central tenets in gerontology. Clearly, neither this notion nor its converse is necessarily true, especially when applied to complex systems such as biological organisms. Yet, in spite ofits doubtful foundation in logic, this "truism" remains clearly implicit in much ofthe current thinking in gerontology and in the experimental work generated by this thinking. But, as various levels of biological organization have been probed for possible causes of senescence, it has become increasingly difficult to discriminate between young and old. * Masonic Medical Research Laboratory, Utica, New York 13501. I wish to thank Drs. V. J. Wulff and Frank C. Erk for their valuable criticisms of the manuscript. Work was supported in part under contract AT(3o-i)-35i8 between the Masonic Foundation for Medical Research and Human Welfare and the United States Atomic Energy Commission. 95 Although, with advancing age, organisms more frequently show signs of certain degenerative diseases, this increased incidence is the result of aging, not its cause. Once a disease has occurred, however, it may contribute to the organism's loss offunctional vigor. On the other hand, the deterioration ofform and function, which are the hallmarks ofsenescence for an integrated biological system, seem to be reflected but slightly, if at all, in physical or chemical changes at lower levels of organization. Yet, gerontologists, by what seems near acclamation, have embraced the general hypothesis that organisms age because cells age. Many of these gerontologists also think that cellular aging is the consequence ofmolecular changes which occur in the biological information system, that is, the system by which DNA-based information is transcribed into RNA and ultimately translated into enzymic protein [2]. These changes are thought of as affecting a loss of information or information potential either by cause ofrandom events occurring at the level ofthe genome or by the programmed expression of "new" and previously masked genetic information, deleterious to the system. What makes this hypothetical construct so appealing is that it places the site of change in the genome, a biological common denominator, where changes can accumulate with time and can affect all manner ofprocesses and functions throughout all levels oforganization. In our laboratory, as we have searched for a common cause of senescence , we too have been mesmerized by the desire to include aging among the phenomena directly explainable in terms of changes in the central biological information system. Concentrating on the molecular level of organization, we have looked, and to some degree continue to look, for physical and chemical changes in the information system which could deleteriously affect its capacity to efficiently furnish correct and timely information in quantities sufficient to sustain an organism's structural and functional integrity. But, for reasons that I will develop, our attention has now become diverted to the study of the dynamic dimensions of biological organization. Rates of biological processes are not constant. Quite to the contrary, they vary not only quantitatively but also cyclically. Some biological rhythms approximate the rhythms of the seasons of the year [3], others those of the lunar month...

This publication has 0 references indexed in Scilit: