Role of alpha-interferon in regulation of apoptosis in cells of the hypothalamo-hypophyseal-adrenocortical system of old mice in oxidative stress

The aim of this work was to demonstrate the role of interferon alpha (IA) in apoptosis control of cells of hypothalamohypophysial adrenocortical system (HHAS) in young and old mice under conditions of hyperoxia. The increase of functional activity of neurosecretory cells of hypothalamic paraventricular nucleus in old mice treated with IA was demonstrated, while no effect was found in young mice. This differences could be associated with aging changes in HHAS in intact old animals. Oxidative stress caused an increase in the number of cells synthesizing proapoptotic c-fos protein in paraventricular nucleus of mice of both age groups. However, the protective action of IA against the stress is expressed more actively and in more early stage of apoptosis in young mice. Thus, the degree of IA participation in the control of programmed cell death of hypothalamic cells depends on the age of the animal. In the adrenal zona fasciculata of young mice the number of apoptotic cells was significantly increased after IA administration while after hyperoxia or its combination with IA it remained at control level. In the adrenal gland of old mice the proportion of apoptotic cells was not different from that found in young mice and remained unchanged after all experimental challenges.