|11-beta-hydroxysteroid dehydrogenase (NADP+)|
|EC number||CAS number||IntEnz||BRENDA||ExPASy||KEGG||MetaCyc||metabolic pathway|
11β-Hydroxysteroid dehydrogenase (HSD-11β or 11β-HSD) is the name of a family of enzymes that catalyze the conversion of inert 11 keto-products (cortisone) to active cortisol, or vice versa, thus regulating the access of glucocorticoids to the steroid receptors:
- 11β-hydroxysteroid + NADP+ an 11-oxosteroid + NADPH + H+
This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is 11beta-hydroxysteroid:NADP+ 11-oxidoreductase. Other names in common use include corticosteroid 11beta-dehydrogenase, beta-hydroxysteroid dehydrogenase, 11beta-hydroxy steroid dehydrogenase, corticosteroid 11-reductase, and dehydrogenase, 11beta-hydroxy steroid. This enzyme participates in c21-steroid hormone metabolism and androgen and estrogen metabolism.
As of late 2007, 8 2IRW.
Cortisol, a glucocorticoid, binds the glucocorticoid receptor. However, because of its molecular similarity to aldosterone it is also capable of binding the mineralcorticoid receptor. Both aldosterone and cortisol have a similar affinity for the mineralocorticoid receptor; however, there is vastly more cortisol in circulation than aldosterone. To prevent over-stimulation of the mineralocorticoid receptor by cortisol, HSD-11β converts the biologically active cortisol to the inactive cortisone, which can no longer bind to the mineralocorticoid receptor. HSD-11β co-localizes with intracellular adrenal steroid receptors. Licorice or Carbenoxolone, which contains glycyrrhetinic acid, can inhibit 11β-HSD and lead to a mineralocorticoid excess syndrome.
|HSD11B1||NADPH-dependent||Highly expressed in key metabolic tissues including liver, adipose tissue, and the central nervous system.||In these tissues, HSD11B1 reduces cortisone to the active hormone cortisol that activates glucocorticoid receptors.|
|HSD11B2||NAD+-dependent||Expressed in aldosterone-selective tissues, including kidneys, colon, salivary glands, and placenta.||In these tissues, HSD11B2 oxidizes cortisol to cortisone and prevents illicit activation of the mineralocorticoid receptor.|
- Medical Subject Headings (MeSH)