Endocrine and metabolic changes in human aging

Abstract

"Aging and death are inevitable. We have no desire to prolong life, if such prolongation entails only added days and years of misery and suffering. On the other hand, for the first time in history, man has within his grasp potent medications of many kinds, among the more important of which are specific hormones capable of retarding if not stopping some of the undesirable features of growing old". Thomas Hodge McGavack Geriatrics 18:181-191 (1963) ABSTRACT Numerous alterations in hormonal secretion occur with aging. In general, these tend towards a disintegration of the normal cyclic secretory patterns resulting in lower total circulating levels. In addition, declines in receptors and postreceptor function further decreases the ability of the hormonal orchestra to maintain coordinated function throughout the organism. Clues to some of these agerelated changes in humans may come from the study of simpler organisms where regulatory systems are known to modulate the aging process. In particular, the interactions among the environment, hormones, and insulin receptor genes have led to new insights into the genetic control of longevity and the development of syndrome X.It is now well established, as summarized in Table 1, that the levels of many hormones are altered with aging (1). Some hormonal levels decrease, reflecting endocrine gland failure, whereas others increase, often because of end organ failure due to a decrease in receptors or a failure of postreceptor function. In the last decade, it has become popular to look to hormone replacement therapy as a mechanism to reverse the aging process. It has become popular to consider this the "hormonal fountain of youth". With aging, dysregulation of food intake accompanied by sarcopenia ('wasting of the flesh") occurs (2). A number of hormonal mechanisms are related to the physiological anorexia of aging (3). In particular, recent studies have suggested that alterations in circulating testosterone levels lead in males to increased leptin levels and thus to anorexia (4).Another area of intense interest in understanding the mechanisms of aging in humans has been the alterations that occur in glucose metabolism with aging and the role of age-related glucose end products (AGE) in accelerating the aging process (5). This area has been closely linked with the changes in nutrition that occur with aging, with insulin resistance, and more recently, with the genes that encode for the insulin receptor. It is of interest that the hormonal changes produced by dietary restriction in rodents are similar to the agerelated hormonal changes in humans, as shown in Table 2 (6). This raises the possibility that these hormonal changes are protective, i,e. slow down metabolism and thus slow down the aging process. This creates a "chicken or egg" hypothesis, illustrated in Figure 1, which asks the question: do aging changes occur because of the decline in hormones or do high hormone levels produce aging changes?This review will briefly examine the available data in each of these areas and...

Frailty and Hormones

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Gender differences in geriatric syndromes as mental illness and nervous system diseases in hospitalized Thai older patients

“…Older individuals face numerous health issues. Besides matters of physical health, especially chronic diseases such as cardiovascular disease, 1 diseases of the circulatory system, 2 endocrine, nutritional, and metabolic diseases, 3 and so on that affect the elderly, mental illness and diseases of the nervous system are serious issues that must be considered.…”