Glucocorticoid Cascade Hypothesis Research Articles

Assessment of the Role of the Glucocorticoid System in Aging Processes and in the Action of Food Restriction

The Glucocorticoid Cascade Hypothesis of Aging and the hypothesis that food restriction retards the aging processes by preventing the development with age of hyperadrenocorticism were investigated. A longitudinal life span study of the daily concentration pattern of plasma corticosterone was conducted in male Fischer 344 rats fed ad libitum or restricted to 60% of the mean food intake of ad libitum fed rats. In another group of ad libitum fed and food-restricted rats, the influence of age on the response of plasma corticosterone levels to restraint stress was measured as was the time course of the return of plasma corticosterone to basal levels following the stress. The findings do not support the hypothesis that food restriction retards the aging processes by preventing the development of hyperadrenocorticism with advancing age. They also indicate that the Glucocorticoid Cascade Hypothesis does not describe a major aspect of the aging processes. Rather, the results suggest the possibility that a lifetime of daily periods of mild hyperadrenocorticism may, if anything, retard the aging processes.

The neuroendocrinology of stress and aging: the glucocorticoid cascade hypothesis.

AS RECENTLY as 1900, tuberculosis, influenza, and pneumonia were the leading causes of death in our country (1). For the most part, however, these infectious diseases, as well as those of poor hygiene or undernutrition, no longer plague us. Instead, we succumb most frequently to heart disease and cancer, diseases of slow degeneration (1). Most of all, unlike so many in the generations before us, we are in a position to age. Regardless of what else occurs, we age, we become more constrained by the discrepancy between what we were and what we have become, and each step becomes harder. The goal in the study of aging is not to halt the process, because we can no more be cured of aging than of birth. The goal, instead, is to slow and soften the sharpest edges of the biological unraveling that constitutes aging. Over the past 5 yr, we have examined some of the sharpest edges of the pathology of aging. We have studied the capacity of aged organisms to respond appropriately to stress and the capacity of stress to cumulatively damage aging tissue.