IL-6, DHEA AND THE AGING PROCESS

The age-related increase in circulating IL-6 levels in humans which ha s been attributed to a decline in DHEA production by the adrenal gland is currently attracting attention because of its possible relevance t o the aetiology and management of a number of age-related clinical dis orders. The potential importance of these observations and suggestions has prompted us to perform more detailed studies on the relationship between IL-6 and DHEA. Using immunoassay techniques we have found in n ormal healthy individuals over the age of 40 an inverse relationship b etween plasma DHEA levels and the presence of detectable levels of IL- 6 (more than 1 pg/ml). In vitro, studies also revealed that low doses (10(-6)-10(-8) M) of DHEA and DHEAS inhibited the production of IL-6 i n unstimulated human spleen cell suspension cultures whilst enhancing its release by explant cultures of the same tissue. In contrast they h ad no effect on immunoglobulin production. These studies suggest that there is a real, but complex relationship between IL-6 production and DHEA levels which warrants further investigation. (C) 1997 Elsevier Sc ience Ireland Ltd.