Dehydroepiandrosterone DHEA

The major androgen or androgen precursor produced by the adrenal cortex is dehydroepiandrosterone (DHEA). Most 17-hydroxypregnenolone follows the glucocorticoid pathway, but a small fraction is subjected to oxidative fission and removal of the two-carbon side chain through the action of 17,20-lyase. The lyase activity is actually part of the same enzyme (P450cl7) that catalyzes 17tt-hydroxylation. This is therefore a dual function protein. The lyase activity is important in both the adrenals and... 

Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulphate, its sulphated derivative... 

The researeh on dehydroepiandrosterone (DHEA) is limited beeause of the laek of radiolabeled metabolites. Robinzon et al. [126] showed that, using pig liver mierosomes, the radiolabeled metabolites of DHEA can be prepared in stable, pure form for bioehemical smdies. They utilized pig liver microsomal (PLM) fractions to prepare pH]-labeled 7a-hydroxy-DHEA (7a-OH-DHEA), 7[3-hydroxy-DHEA (7P-OH-DHEA), and 7-oxo-DHEA substrates from 50 pM [1,2,6,7-3H]DHEA. The metabolites were separated by silica gel PLC plates using ethyl aeetate-hexane-gla-eial aeetic acid (18 8 , v/v) as the mobile phase, extracted with ethyl aeetate, and dried under a stream of nitrogen. The purity of markers was determined with the use of TLC and GC/MS. 

The zona reticularis produces the androgens androstene-dione, dehydroepiandrosterone (DHEA), and the sulfated form of dehydroepiandrosterone (DHEA-S). Only small amounts of testosterone and estrogen are produced in the adrenal glands. Androstenedione and DHEA are converted in the periphery, largely to testosterone and estrogen. 

Robel, P and Baulieu, E.-E. 1995. Dehydroepiandrosterone (DHEA) is a neuroactive neurosteroid. Annals of the New York Academy of Sciences 774 82-110. 

WeEl-Engerer S, David JP, Sazdovitch V, Liere P, Schumacher M, et al. 2003. In vitro metabolism of dehydroepiandrosterone (DHEA) to 7alpha-hydroxy-DHEA and Delta5-androstene-3beta,17beta-diol in specific regions of the aging brain from Alzheimer s and non-de-mented patients. Brain Res 969 117-125. 

In some countries dietary supplements containing dehydroepiandrosterone (DHEA) or dehydroepiandrosterone sulfate (DHEAS) have been advertised with claims that they may be beneficial for a wide variety of ailments. However, there is a lack of any proven benefit from DHEA supplementation. 

Androstenedione, dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DHEA-S) are other mildly androgenic compounds of secondary importance in males and females. The gonads and the adrenal cortex are capable of secreting androstenedione... 

Fluasterone is a stable adrenocortical steroid, a 16a-fluoro analogue of prasteron [dehydroepiandrosterone (DHEA)j. It is currently developed (phase II) for the treatment of metabolic syndrome (i.e. insulin resistance). Electrophilic... 

Wolkowitz OM, Reus VI, Roberts E, et al Dehydroepiandrosterone (DHEA) treatment of depression. Biol Psychiatry 41 311-318, 1997... 

DHEA Dehydroepiandrosterone DHEAS Dehydroepiandrosterone sulfate ERE Estrogen response element FSH Follicle-stimulating hormone GnRH Gonadotropin-releasing hormone HDL High-density lipoprotein... 

Griffiths et al. [23] studied the ESI MS of sterols, and while they are not hormonal steroids, similar derivatization methods can be used. He converts 3/5-hydroxy-A5 sterols to - -4-ene sterols using cholesterol oxidase and follows this by preparation of Girard P hydrazones. This increases the sensitivity by 1000 in ESI. This technique would also be applicable to pregnenolone, dehydroepiandrosterone (DHEA) and similar A5 steroids, which can also be oxidized by cholesterol oxidase. 

Dehydroepiandrosterone (DHEA) is a precursor hormone secreted by the adrenal cortex and to a lesser extent by the central nervous system (Chapter 40 The Gonadal Hormones Inhibitors). It is readily converted to androstenedione, testosterone, and androsterone. In peripheral tissues, aromatase converts DHEA to estradiol. In the plasma, DHEA is converted to DHEA sulfate (DHEAS). 

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