Androgen metabolism in vitro by human leukocytes, variations with sex and age

The present study was undertaken in order to examine the metabolism of androgens by isolated human leukocytes. After incubation, steroids were extracted and purified by high performance liquid chromatography (HPLC); identification and quantification of the steroid products was achieved by gas-liquid-chromatography (GLC), radio-GLC and combined gas chromatography-mass spectrometry (GC-MS) of the trimethylsilyl derivatives (TMS). Incubation in the presence of testosterone led to the formation of 4-ene-androstenedione and 5 alpha-dihydrotestosterone (5 alpha-DHT) while in the presence of 5 alpha-DHT, the products were 5 alpha-androstane-3 alpha, 17 beta-diol (5-Ad) and 5 alpha-androstane-3 beta, 17 beta-diol. The formation of these metabolites was compared in healthy males and females of two age groups. Production of 5 alpha-DHT and 5-Ad was significantly higher in males than in females. In subjects aged 75 years or more, formation of these steroids was decreased by more than half in both sexes, but the sex differences remained. This study confirms the presence in human leukocytes of 17 beta-hydroxysteroid oxydoreductase, 5 alpha-reductase and 3 alpha- and 3 beta-hydroxysteroid oxydoreductase activities.