Endocrine Abstracts

Introduction: DHEA is a well-known neurosteroid. Its plasmatic level is reduced with ageing in most individuals. A non-negligible portion of DHEA is hydroxylated at C7 and C16 to 7α-, 7β- and 16α- and 16β-hydroxyderivatives. A part of the antiglucocorticoid function of DHEA has been described to its 7-oxygenated metabolites, namely to 7α-hydroxy-DHEA. Due its anti-glucocoticoid action it is also considered a factor in fat deposition processes. Thus, we were interested in examining daily profiles of DHEA and its metabolites, as well as possible associations with daily variation of hormones associated with food intake.

Description of methods: 8 women of reproductive age with normal BMI were given five standardised meals, and their hormonal milieu was determined during the course of the day. Plasma from 12 withdrawals was analysed for DHEA and its 7- and 16-hydroxylated metabolites. The Ethical Committee of the Institute of Endocrinology approved the study.

Results: Free DHEA showed a small but significant decrease after lunch and dinner, whereas conjugated DHEA decreased only after dinner. Androstenediol decreased after lunch, but other changes were not significantly influenced by meals. 7α-hydroxy-DHEA and 3β,7α,17β-hydroxyandrostentriol followed the profile of DHEA, but 7β-isomer, 7-oxo-derivative and 3β,7β,17β-hydroxy-androstentriol did not. DHEA and all its derivatives showed an increase at 2200–2300 h, which, however, was significant only for free and conjugated DHEA, 7β-hydroxy-DHEA and 16α-hydroxy-DHEA.

Conclusion: The daily profile of DHEA levels shows a decrease throughout the day from the highest values in the morning value, with additional significant decreases after main meals. Only some hydroxylated metabolites and conjugated derivatives show a similar profile.

Disclosure: This work was supported by the grants ‐ NT12340, NT13890-4, NT11277-6 IGA MZCR and GAUK 1254314 Charles University, Prague.