Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
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Drug
Enzyme
Compound
Query: EC:3.1.6.1 (
sulfatase
)
3,205
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The metabolism of various radiolabeled steroids by cultured human epidermal keratinocytes was studied in an attempt to identify the steroid-metabolizing enzymes present in these cells. Sulfatase activity was demonstrated in keratinocytes with either E1S or DS as substrates. The products of
sulfatase
action were E1 and DHEA, respectively. The specific activity of the enzyme was approximately 5- to 14-fold greater with E1S as the substrate compared with DS, and the rates of hydrolysis were linear with incubation time up to 3 h. The metabolism of DHEA by the keratinocyte 17 beta-HSOR-catalyzed reaction resulted in the predominant formation of 5-androstene-3 beta,17 beta-diol. The rate of formation of 5-androstene-3 beta,17 beta-diol was linear with time of incubation up to 18 h, and the specific activity of 17 beta-HSOR, with DHEA as the substrate, was greater in keratinocytes maintained in culture for 4 weeks compared with keratinocytes kept in culture for 1 week. Androstenedione was a minor product of DHEA metabolism. The metabolism of DHT by epidermal keratinocytes resulted in the formation of 5 alpha-androstanedione, 5 alpha-androstane-3 alpha,17 beta-diol, 5 alpha-androstane-3 beta,17 beta-diol, androsterone, and isoandrosterone: the rates of formation of 5 alpha-androstane-3 alpha,17 beta-diol and 5 alpha-androstane-3 beta,17 beta-diol were linear with incubation time up to 24 h, and the specific activities of 3 alpha-HSOR and 3 beta-HSOR did not appear to change with keratinocyte time in culture up to 3 weeks. The metabolism of DOC by epidermal keratinocytes resulted in 5 alpha-dihydrodeoxycorticosterone production: the rate of formation of this metabolite was linear with incubation time up to 4 h. The metabolism of E1 by epidermal keratinocytes yielded E2, and that of E2 resulted in the formation of E1. The rate of E1 formation from E2, was approximately 10-fold greater than the rate of formation of E2 from E1; these rates were linear with incubation time up to 4 h. Epidermal keratinocytes maintained in culture did not metabolize androstenedione to either E1 or E2, and pregnenolone was not metabolized by these cells. This study serves to ascertain that epidermal keratinocytes express
steroid 5 alpha-reductase
, 17 beta-HSOR, 3 beta-HSOR, 3 alpha-HSOR, 3 beta-hydroxysteroid oxidoreductase-delta 5----4-isomerase, and
sulfatase
activities.
...
PMID:Steroid metabolism by epidermal keratinocytes. 247 Mar 8