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11β‐Hydroxysteroid dehydrogenase expression and activity in the human adrenal cortex
Author(s) -
Mazzocchi Giuseppina,
Rossi Gian Paolo,
Neri Giuliano,
Malendowicz Ludwik K.,
Albertin Giovanna,
Nussdorfer Gastone G.
Publication year - 1998
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.12.14.1533
Subject(s) - endocrinology , cortisone , medicine , adrenal cortex , corticosterone , aldosterone , mineralocorticoid , 11β hydroxysteroid dehydrogenase type 1 , aminoglutethimide , glucocorticoid , chemistry , secretion , metyrapone , dehydrogenase , biology , enzyme , hormone , biochemistry , cancer , breast cancer , aromatase
Although oxidation of Cortisol or corticosterone by 11β‐hydroxysteroid dehydrogenase (11β‐HSD) represents the physiological mechanism conferring specificity for aldosterone on the mineralocorticoid receptor in mineralocorticoid target tissues, little attention has been paid until now to the expression and activity of this enzyme in human adrenals. We have shown that human adrenal cortex expresses 11β‐HSD type 2 (11β‐HSD2) gene, and found a marked 11β‐HSD2 activity in microsomal preparations obtained from slices of decapsulated normal human adrenal cortices. Under basal conditions, adrenal slices secreted, in addition to cortisol and corticosterone (B), sizeable amounts of cortisone and 11‐dehydrocorticosterone (DH‐B), the inactive forms to which the former glucocorticoids are converted by 11β‐HSD. Addition of the 11β‐HSD inhibitor glycyrrhetinic acid elicited a moderate rise in the production of cortisol and B and suppressed that of cortisone and DH‐B. ACTH and angiotensin II evoked a marked rise in the secretion of cortisol and B, but unexpectedly depressed the release of cortisone and DH‐B. ACTH also lowered the capacity of adrenal slices to convert [ 3 H]cortisol to [ 3 H]cortisone. This last effect of ACTH was concentration‐dependently abolished by both aminoglutethimide and cyanoketone, which blocks early steps of steroid synthesis, but not by metyrapone, an inhibitor of 11β‐hydroxylase. Collectively, these findings indicate that the human adrenal cortex possesses an active 11β‐HSD2 engaged in the inactivation of newly formed glucocorticoids. The activity of this enzyme is negatively modulated by the main agonists of glucocorticoid secretion through an indirect mechanism, probably involving the rise in the intra‐adrenal concentration of non‐11β‐hydroxylated steroid hormones.—Mazzocchi, G., Rossi, G. P., Neri, G., Malendowicz, L. K., Albertin, G., Nussdorfer, G. G. 11β‐Hydroxysteroid dehydrogenase expression and activity in the human adrenal cortex. FASEB J. 12, 1533–1539 (1998)