The conversion of 16β hydroxyldehydroepiandrosterone in human serum.
Steroids 2016;
109:50-5. [PMID:
26896786 DOI:
10.1016/j.steroids.2016.02.007]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 01/20/2016] [Accepted: 02/11/2016] [Indexed: 10/22/2022]
Abstract
The circulating levels of 16β hydroxydehydroepiandrosterone (16β OH-DHEA) are at the limit of detection (less than 10 pg/mL), unlike the serum concentrations of 16α-hydroxydehydroepiandrosterone (16α OH-DHEA, 10-300 pg/mL) in premenopausal, postmenopausal and male serum. A major reason could be the rapid conversion of 16β OH-DHEA to 5-androstene-3beta, 17beta-diol 16 one (3β, 17β-diol 16-oxo) in serum due to the stereospecific structure of 16β OH-DHEA. In ultrapure H2O, there is no apparent conversion observed while 16β OH-DHEA (10 ng/mL) spiked in stripped or unstripped serum is quickly converted to 3β, 17β-diol 16-oxo at room temperature. During this conversion, a further converted product was observed with a difference in molecular weight of 16 Da from that of 16β OH-DHEA and 3β, 17β-diol 16-oxo, which could be their hydroxylation product, i.e. triol-ketone. Under basic conditions, further conversion occurs. The present data can explain the practically undetectable concentration of serum 16β OH-DHEA while 3β, 17β-diol 16-oxo is at the level of less than 50 pg/mL. Serum concentrations of (0.0-9.9 pg/mL for 16β OH-DHEA, 8.9-50.7 pg/mL for 3β, 17β-diol 16-oxo and 10.0-285.0 pg/mL for 16α OH-DHEA are measured in sera of premenopausal, postmenopausal women and men over 50 years of age.
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