7-Hydroxydehydroepiandrosterone epimers in the life span

Evidence has been accumulated that 7-hydroxyepimers of dehydroepiandrosterone (7-OH-DHEA), may act as locally active immunomodulatory and immunoprotective agents, counteracting exaggerated actions of glucocorticoids. Since Skinner et al. (1977) developed the first unspecific RIA, it has been known that 7alpha-OH-DHEA is present in near nanomolar concentration in human blood. No data have been available, however, on its changes during the human life. Using recently developed specific radioimmunoassays for determination of both 7-OH-DHEA epimers, 7alpha- and 7beta-OH-DHEA were measured in sera from 252 males and 172 females, representing age groups from 10 to 91 years (males) and from 10 to 72 years (females). The dependence of 7-OH-DHEA levels on age was evaluated by using polynomial fitting of the 4th or 5th degree. In contrast to men, where a distinct decline with age occurred, two local maxima have been recorded round the age 22 and 53, respectively, in females. The curves of age dependence of 7-OH-DHEA levels in both sexes resembled those of previously determined unconjugated DHEA, but in the latter case the second maximum in women was found about 10 years earlier than 7-OH-DHEA, in a premenopausal period. The levels of both 7-OH-DHEA epimers correlated excellently with each other.