Conversion of progesterone to corticosteroids by the midterm fetal adrenal and kidney

Midterm fetal adrenal and kidney tissue homogenates were incubated with 3H-progesterone (1 microM) and its conversion to te 3H-corticosteroids metabolites studied. Cortisol (36.3%) and corticosterone (4.7%) were isolated from the adrenal, and 11-deoxycortisol (32.5%) and deoxycorticosterone (21.1%) from the kidney. The results of these incubations confirmed the presence of 17- and 21-hydroxylase activities in both fetal tissues, and that of 11 beta-hydroxylase activity only in fetal adrenal tissue. We conclude that during pregnancy when progesterone levels are high, biosynthesis by the fetal kidney of 11-deoxycortisol, the most abundant corticosteroid formed by this tissue in this investigation, might provide to the fetal adrenal an important precursor for cortisol biosynthesis within the fetal compartment.     

Androstenedione-mediated inhibition of 11 beta-hydroxylation in monolayer cell cultures of fetal calf adrenals

The possibility that the formation of androstenedione by fetal calf adrenal cells in culture is linked to their decreased ability to form cortisol and corticosterone was investigated. Fetal calf adrenal cells metabolise radioactive adrostenedione to two major products which coelute on thin layer chromatography with 11 beta-hydroxyandrostenedione and 11 beta-hydroxytestosterone. When the cells are incubated with 11-deoxycortisol or 11-deoxycorticosterone in the presence of androstenedione there is a dose dependant inhibition of cortisol and corticosterone formation. Further studies with progesterone showed an accumulation of 11-deoxycortisol and 11-deoxycorticosterone in cells incubated simultaneously with androstenedione. The results demonstrate that exogenous androstenedione can have dramatic effects on steroidogenesis in the fetal calf adrenal and suggest that the accumulation of androstenedione in the medium of cultured andrenocortical cells is responsible, at least in part, for the decreased formation of cortisol and corticosterone.     

Increased adrenal steroid secretion in response to CRF in women with hypothalamic amenorrhea

OBJECTIVE: To evaluate adrenal steroid hormone secretion in response to corticotropin-releasing factor (CRF) or to adrenocorticotropin hormone in women with hypothalamic amenorrhea. DESIGN: Controlled clinical study. SETTING: Department of Reproductive Medicine and Child Development, Section of Gynecology and Obstetrics, University of Pisa, Italy. PATIENT(S): Fifteen women with hypothalamic amenorrhea were enrolled in the study. Eight normal cycling women were used as control group. INTERVENTION(S): Blood samples were collected before and after an injection of ovine CRF (0.1 microg/kg iv bolus) or after synthetic ACTH (0.25 mg iv). MAIN OUTCOME MEASURE(S): Plasma levels of ACTH, 17-hydroxypregnenolone (17OHPe), progesterone (P), dehydroepiandrosterone (DHEA), 17-hydroxyprogesterone (17OHP), cortisol (F), 11-deoxycortisol (S) and androstenedione (A). RESULT(S): Basal plasma concentrations of ACTH, cortisol, 11-deoxycortisol, DHEA and 17OHPe were significantly higher in patients than in controls, whereas plasma levels of progesterone and 17-OHP were significantly lower in patients than in controls. In amenorrheic women the ratio of 17-OHPe/DHEA, of 17-OHPe/17-OHP and of 11-deoxycortisol/cortisol were significantly higher than in controls, while a significant reduction in the ratio of 17-OHP/androstenedione, of 17-OHP/11-deoxycortisol was obtained. In response to corticotropin-releasing factor test, plasma levels of ACTH, cortisol, 17-OHP, 11-deoxycortisol, DHEA and androstenedione were significantly lower in patients than in controls. In response to adrenocorticotropin hormone, plasma levels of 17-OHP, androstenedione and androstenedione/cortisol were significantly higher in patients than in controls. CONCLUSIONS: Patients suffering for hypothalamic amenorrhea showed an increased activation of hypothalamus-pituitary-adrenal (HPA) axis, as shown by the higher basal levels and by augmented adrenal hormone response to corticotropin-releasing factor administration. These data suggest a possible derangement of adrenal androgen enzymatic pathway.     

18-Hydroxy-11-deoxycortisol: a new steroid isolated from incubations of the adrenal with 11-deoxycortisol

Cortisol has been shown to be metabolized in the zona glomerulosa of the adrenal gland through the same pathway involving the cytochrome P-450, corticosterone methyl oxidase by which corticosterone is transformed to 18-hydroxycorticosterone and aldosterone. When cortisol is the precursor, 18-hydroxycortisol and 18-oxocortisol are formed. 18-Hydroxycortisol can also be made at a similar rate in the bovine zona fasciculata and reticularis as in the zona glomerulosa. We studied the possibility that the formation of 18-hydroxycortisol in the zona fasciculata and reticularis might be through a different pathway involving initial 18-hydroxylation of 11-deoxycortisol before 11 beta-hydroxylation. Rat adrenal capsules or cores were incubated with 10 micrograms of cortisol or 11-deoxycortisol and the formation of 18-hydroxycortisol was measured by radioimmunoassay. Both capsules and cores transformed 11-deoxycortisol to 18-hydroxycortisol, but cortisol was only transformed in the capsular portion. Sixty-two rat adrenals were incubated with 10 mg of 11-deoxycortisol and the putative steroid, 18-hydroxy-11-deoxycortisol, was purified by TLC and HPLC and subjected to gas chromatography mass spectrometry. The mass spectra indicated that the steroid isolated was indeed 18-hydroxy-11-deoxycortisol. The function of this steroid is still unknown.     

Disorders of the aldosterone synthase and steroid 11beta-hydroxylase deficiencies

The most potent corticosteroids are 11beta-hydroxylated compounds. In humans, two cytochrome P450 isoenzymes with 11beta-hydroxylase activity, catalysing the biosynthesis of cortisol and aldosterone, are present in the adrenal cortex. CYP11B1, the gene encoding 11beta-hydroxylase (P450c11), is expressed on high levels in the zona fasciculata and is regulated by ACTH. CYP11B2, the gene encoding aldosterone synthase (P450c11Aldo), is expressed in the zona glomerulosa under primary control of the renin-angiotensin system. Aldosterone synthase has 11beta-hydroxylase activity as well as 18-hydroxylase activity and 18-oxidase activity. The substrate for CYP11B2 is 11-deoxycorticosterone, that of CYP11B1 is 11-deoxycortisol. Mutations in CYP11B1 cause congenital adrenal hyperplasia (CAH) due to 11beta-hydroxylase deficiency. This disorder is characterized by androgen excess and hypertension. Mutations in CYP11B2 cause congenital hypoaldosteronism (aldosterone synthase deficiency) which is characterized by life-threatening salt loss, failure to thrive, hyponatraemia and hyperkalaemia in early infancy. Both disorders have an autosomal recessive inheritance. Classical and nonclassical forms of 11beta-hydroxylase deficiency can be distinguished. Studies in heterozygotes for classical 11beta-hydroxylase deficiency show inconsistent results with no or only mild hormonal abnormalities (elevated plasma levels of 11-deoxycortisol after ACTH stimulation). In infants with congenital hypoaldosteronism, a comparable frequency of 18-hydroxylase deficiency (aldosterone synthase deficiency type I) and of 18-oxidase deficiency (aldosterone synthase deficiency type II) can be found. Molecular genetic studies of the CYP11B1 and CYP11B2 genes in 11beta-hydroxylase deficiency or aldosterone synthase deficiency have led to the identification of several mutations. Transfection experiments showed loss of enzyme activity in vitro. In some of the patients with 18-oxidase deficiency (aldosterone synthase deficiency type II) no mutations in the CYP11B2 gene were identified. Refined methods for steroid determination are the basis for the diagnosis of inborn errors of steroidogenesis. Molecular genetic studies are complementary; on the one hand, they have practical importance for the prenatal diagnosis of virilizing CAH forms and on the other hand, they are of theoretical importance in terms of our understanding of the functioning of cytochrome P450 enzymes. Copyrightz1999S.KargerAG, Basel     

Studies on the metabolism of steroid hormones in a virilizing adrenal cortex adenoma.

Slices of an adreno-cortical adenoma which had been obtained at operation from an 11-year-old girl with clinical signs of virilism were incubated with each of the following steroids: [1,2-3H]progesterone, [4-14C]pregnenolone, [1,2-3H]testosterone, [4-14C]androstenedione and [7-3H]dehydroepiandrosterone, respectively. Isolation and identification of the free radioactive metabolites were achieved by gel column chromatography on Sephadex LH-20, thin-layer chromatography, radio gas chromatography and isotope dilution. After incubation of progesterone, the following metabolites were identified: 11beta-hydroxyprogesterone, 16alpha-hydroxyprogesterone, 17alpha-hydroxyprogesterone, 21-deoxycortisol, corticosterone and cortisol. Pregnenolone was metabolized to 17alpha-hydroxypregnenolone, progesterone, dehydroepiandrosterone, androstenedione and 11beta-hydroxyandrostenedione. When testosterone was used as substrate, 11beta-hydroxytestosterone, androstenedione and 11beta-hydroxyandrostenedione were found as metabolites, whereas androstenedione was metabolized to testosterone and 11beta-hydroxyandrostenedione. After incubation of dehydroepiandrosterone, only androstenedione and 11beta-hydroxyandrostenedione were isolated and identified. From these results, it appears that cortisol was formed in the adenoma tissue via 21-deoxycortisol and corticosterone. Delta4-3oxo steroids of the C19-series arose exclusively from pregnenolone via 17alpha-hydroxypregnenolone and dehydroepiandrosterone, and not from progesterone and 17alpha-hydroxyprogesterone. Calculated on the amounts of metabolites formed, the highest enzyme activities were those of the 11beta-hydroxylase and the 17alpha-hydroxylase. It is interesting to note that only traces of testosterone were detected after incubation of androstenedione, whereas testosterone yielded large amounts of androstenedione.     

Evidence of 11 beta-hydroxylase deficiency in a patient with cortical adrenal adenoma

We explored a 61 year old woman with mild hirsutism. An adrenal tumor was found in the left adrenal, which was held responsible for the androgen secretion. The in vitro incubation of the tumor tissue showed an impaired 11 beta-hydroxylation of 11-deoxycortisol. This is a rare and unusual case of adrenal pathology showing that a deficiency in 11 beta-hydroxylase activity does not rule out the presence of an adrenocortical adenoma.     

Efficient conversion of 11-deoxycortisol to cortisol (hydrocortisone) by recombinant fission yeast Schizosaccharomyces pombe

Genetically engineered microorganisms are being increasingly used for the industrial production of complicated chemical compounds such as steroids; however, there have been few reports on the use of the fission yeast Schizosaccharomyces pombe for this purpose. We previously have demonstrated that this yeast is a unique host for recombinant expression of human CYP11B2 (aldosterone synthase), and here we report the functional production of human CYP11B1 (steroid 11beta-hydroxylase) in S. pombe using our new integration vector pCAD1. In the human adrenal, the mitochondrial cytochrome P450 enzyme CYP11B1 catalyses the conversion of 11-deoxycortisol to cortisol, a key reaction in cortisol biosynthesis that in addition is of fundamental interest for the technical synthesis of glucocorticoids. We observed that the endogenous mitochondrial electron transport system detected previously by us is capable of supplying this enzyme with the reducing equivalents necessary for steroid hydroxylation activity. Under optimised cultivation conditions the transformed yeasts show in vivo the inducible ability to efficiently and reliably convert deoxycortisol to cortisol at an average rate of 201 microM d(-1) over a period of 72h, the highest value published to date for this biotransformation.     

Corticoid formation by the monkey fetal adrenal: Evaluation of 17-, 21- and 11-hydroxylase activities

There is indirect evidence that cortisol synthesis in the fetal rhesus monkey adrenal gland is limited at Day 135 of gestation but increases thereafter. This study was conducted to ascertain whether a reduced synthetic capacity is caused by a deficiency in 17-, 21- or 11-hydroxylase activity. For the sake of comparison 11- and 21-hydroxylases were also estimated in adult adrenals. 11-, 21-Hydroxylases were measured in the entire adrenal by the oxidation of NADPH by mitochondria and microsomes, respectively. 17-Hydroxylase was evaluated in outer and inner regions of the fetal gland by the formation of [³H]17-hydroxyprogesterone, -11-deoxycortisol, -cortisol and -androstenedione from [³H]progesterone. The maximum velocity of both the 11- and 21-hydroxylase was similar in fetal and adult glands indicating that corticoid formation in the fetus is not constrained by levels of these enzymes.[³H]Progesterone was extensively metabolized to -17-hydroxyprogesterone, -androstenedione, -11-deoxycortisol and -cortisol by homogenates from both regions of the fetal adrenal. The ratio of [³H]-cortisol to [³H]11-deoxycortisol was consistently higher in incubations of the inner glandular area. Together, these findings indicate that 17-hydroxylase is also active at Day 135 and that the 11-hydroxylase may be more concentrated in the fetal cortex. These data suggest in addition that the restriction in cortisol formation occurs at a step prior to the metabolism of progesterone to cortisol.     

An adrenocortical tumor secreting weak mineralocorticoids

An adrenocortical carcinoma (15.5 g) secreting excessive amounts of steroids with weak mineralocorticoid activity in a 25-year-old woman was studied with particular reference to its in vivo and in vitro secretions of steroids. Severe hypertension, occasional low serum potassium and suppressed PRA were the major clinical findings, and were improved with removal of the tumor. In the preoperative stage, plasma levels of 11-deoxycorticosterone, 18-hydroxy-11-deoxycorticosterone, corticosterone and 18-hydroxycorticosterone were all increased. However, the plasma level of aldosterone was repeatedly normal. Although plasma levels of pregnenolone, 17-hydroxypregnenolone, progesterone and 17-hydroxyprogesterone were very high, those of other late step steroids, i.e. 11-deoxycortisol, cortisol, dehydroepiandrosterone, androstenedione and testosterone were almost normal. From these findings, a major etiological role of weak mineralocorticoids such as 11-deoxycorticosterone, 18-hydroxycorticosterone and corticosterone in her hypertension was suggested. Pregnenolone and 17-hydroxypregnenolone in tumor tissue were increased, but 11-deoxycorticosterone, corticosterone, aldosterone, cortisol and adrenal androgens such as dehydroepiandrosterone, androstenedione and testosterone were below normal or low normal. In vitro production of 11-deoxycorticosterone, aldosterone or cortisol by the tumor tissue slices was very low and scarcely responded to synthetic ACTH.     

Potency and selectivity of the aromatase inhibitor R 76,713. A study in human ovarian, adipose stromal, testicular and adrenal cells

The effects of R 76,713 on steroidogenesis were studied in primary cultures of four different human cell types, i.e. ovarian granulosa cells, adipose stromal cells, testicular cells and adrenal cells. In human granulosa cells aromatization of [1 beta, 2 beta-3H]androstenedione (as measured by the release of tritiated water) showed a Km (Michaelis constant) of 78 nM. R 76,713 competitively inhibited aromatization with a Ki (dissociation constant of the enzyme-inhibitor complex) of 1.6 nM. In human adipose stromal cells aromatization was measured by following the conversion of androstenedione to estrone and 17 beta-estradiol. In this system a Km for aromatization of androstenedione of 10.8 nM was found. R 76,713 again showed competitive kinetics with a Ki-value of 0.14 nM. In human testicular cells the synthesis of the androgens testosterone, androstenedione and dehydroepiandrosterone was only inhibited by drug concentrations exceeding 10(-6) M. At 10(-5) M of R 76,713, steroid concentrations were lowered to 56, 64 and 81% of the control for testosterone, androstenedione and dehydroepiandrosterone respectively. Concomitantly, a slight increase in the levels of pregnenolone (138% of the control) and progesterone (133% of the control) was seen. In human adrenal cells the synthesis of cortisol and aldosterone was slightly affected by R 76,713 also at concentrations exceeding 10(-6) M. At 10(-5) M of R 76,713 the concentrations of cortisol and aldosterone were lowered to respectively 59 and 51% of the control. At the same drug concentration the precursors 11-deoxycortisol and 11-deoxycorticosterone rose to 189 and 147% of the control. These results show that in primary cultures of human cells, R 76,713 is a very potent aromatase inhibitor with a selectivity of at least 1000-fold compared to other steps in steroidogenesis.     

Corticotropin-induced changes in enzymatic activities of the post-pregnenolone steroidogenic pathway in rabbit adrenocortical cells

In an attempt to delineate the effect of corticotropin (ACTH) on post-pregnenolone steroidogenesis, the activity of enzymatic systems operative in conversion of pregnenolone into glucocorticoids and androgens was studied in adrenocortical cells from control rabbits and from animals treated with ACTH for 12 days (ACTH 1-24, 200 micrograms s.c. daily). The cells from ACTH-treated rabbits exhibited an increased overall steroidogenic capacity and produced much more cortisol (P less than 0.0005) as well as other 17-hydroxylated steroids as a result of increased activity of 17 alpha-hydroxylase; corticosterone generation was concomitantly reduced. The increased conversion of pregnenolone or progesterone into androgens, as a result of previous treatment with ACTH, provides additional evidence for an effect of ACTH on 17 alpha-hydroxylase activity. A stimulatory effect of ACTH on 11 beta-hydroxylase was also evidenced by these cells, since conversion of 11-deoxycortisol into cortisol was enhanced (P less than 0.005). The increased production of androgens from 17-hydroxylated precursors by cells from ACTH-treated rabbits suggests that ACTH also exerts a prolonged stimulatory effect on 17,20-lyase. The activity of 3 beta-hydroxysteroid dehydrogenase-isomerase was apparently not influenced by chronic treatment with ACTH, judged from unchanged conversion of dehydroepiandrosterone into androstenedione. The activity of 11 beta-dehydrogenase was likewise unchanged in these conditions.     

Biotransformation of pregnenolone - 7alpha-3H, progesterone - 7alpha-3H and dehydroepiandrosterone - 7alpha-3H by porcine fetal and maternal adrenal homogenate preparations.

The biotransformation of pregnenolone-7alpha-3H and of progesterone-7alpha-3H by porcine fetal and maternal adrenal homogenates at 56 and 112 days of pregnancy and of dehydroepiandrosterone-7alpha-3H by fetal adrenal homogenates has been investigated in vitro. Both pregnenolone-7alpha-3H and progesterone-7alpha-3H were metabolized extensively by maternal adrenal preparations, the principal radioactive metabolites isolated being cortisol, corticosterone, 11-deoxycortisol, deoxycorticosterone, 11beta-hydroxyprogesterone and androstenedione. In addition, 17alpha-hydroxyprogesterone, 20alpha-dihydroprogesterone and cortisone were formed from both substrates and 17alpha-hydroxypregnenolone and progesterone were formed from pregnenolone. Although essentially the same radioactive metabolites were isolated after incubation of fetal adrenal glands with pregnenolone-7alpha-3H or progesterone-7alpha-3H, a greater proportion of the radioactivity was associated with corticosteroids at 112 days of pregnancy than at 56 days. 11beta-Hydroxyandrostenedione and androstenedione were isolated and identified together with an unknown polar metabolite, after incubation of fetal adrenal tissue with dehydroepiandrosterone-7alpha-3H. These results are discussed in relation to feto-placental steroid biosynthesis and metabolism and the role of the fetal adrenal in the initiation of parturition in the pig.     

Effects of cyproterone acetate on adrenal steroidogenesis in vitro

The effects of cyproterone acetate (CA) on steroidogenesis in isolated guinea-pig adrenal cells have been investigated by measuring the production of cortisol, its immediate precursors (11-deoxycortisol and 17-hydroxyprogesterone), and adrenal androgens (delta 4-androstenedione and dehydroepiandrosterone). Used at a dose of 2 micrograms/ml, CA provoked a sharp drop in the production of cortisol, aldosterone and 11-deoxycortisol. By contrast, 17-hydroxyprogesterone, delta 4-androstenedione and dehydroepiandrosterone were increased, which suggests that 21-hydroxylase activity is inhibited. With concentrations above 2 micrograms/ml CA, it would seem to be the 3-beta-ol-dehydrogenase-delta 4,5-isomerase complex that is affected, since dehydroepiandrosterone exhibited a sudden increase, whereas 17-hydroxyprogesterone and delta 4-androstenedione showed a relative decrease. The enzymatic system or systems involved therefore appear to be linked to the concentration of CA used but, whatever the case, the drop in cortisol production is accompanied by a decrease in aldosterone and an increase in adrenal androgen levels.     

Differential modulation of ACTH-stimulated cortisol and androstenedione secretion by insulin

Results of previous clinical studies suggested counter regulatory actions between insulin and DHEA(S). The present studies were performed using primary monolayer cultures of bovine fasciculata-reticularis cells to test the hypothesis that insulin directly affects adrenal androgen secretion. Although having no independent effect, insulin exhibited complex time- and concentration-specific actions on ACTH-stimulated secretion of both C21 (cortisol) and C19 (androstenedione) corticosteroids. In the presence of low concentrations (0.05-0.1 nM) of ACTH, cortisol secretion during a 2 h incubation was about 2-fold greater in the presence than in the absence of insulin (0.01-100 ng/ml). In the presence of a maximal concentration (10 nM) of ACTH, on the other hand, cortisol secretion was not affected by insulin at concentrations less than or equal to 0.1 ng/ml, but was decreased at higher insulin concentrations. ACTH-stimulated androstenedione secretion was not significantly affected by insulin during a short-term (2 h) incubation. During a prolonged (24 h) incubation, insulin produced a concentration-dependent inhibition of ACTH-stimulated cortisol secretion. At an insulin concentration of 100 ng/ml, ACTH (10 nM)-stimulated cortisol secretion declined to a level only 30% of that produced by ACTH alone. In contrast, insulin exhibited biphasic effects on the secretion of androstenedione by cells maintained in the presence of ACTH for 24 h; an effect that was most dramatic in the presence of a maximal concentration of ACTH. At an insulin concentration of 0.1 ng/ml, androstenedione secretion by cells maintained in the presence of 10 nM ACTH was increased approximately 2.5-fold. At higher concentrations of insulin, ACTH-stimulated androstenedione secretion was inhibited to an extent comparable to that in cortisol secretion. The effects of insulin on ACTH-stimulated cortisol and androstenedione secretion could not be accounted for by changes in steroid degradation or a loss in 11 beta-hydroxylase activity. These results indicate that insulin interacts with ACTH to modulate the secretion of both C21 and C19 corticosteroids and that physiological concentrations (less than or equal to 1 ng/ml) of insulin may have a long-term effect to enhance selectively adrenal androgen secretion. These data are consistent with a servo mechanism between insulin and DHEA(S) in vivo and indicate that the correlations observed clinically result, at least in part, from a direct action of insulin to modulate the rate of adrenal androgen production.     

Inhibition of cortisol production in isolated guinea-pig adrenal cells

Cortisol, added to 1 ml incubation medium containing 3-4 X 10(5) isolated guinea-pig adrenal cells, provoked a decrease in basal and ACTH (250 pg)-stimulated cortisol production, in correlation with the amounts used (50 ng-2,000 ng). A decrease in aldosterone production could be seen when cortisol concentrations reached or exceeded 1,000 ng/ml. There were no variations in either androgens (delta 4-androstenedione, dehydropiandrosterone) or 17-hydroxyprogesterone. Only 11-deoxycortisol was slightly increased. Using increasing concentrations of ACTH (50-250 pg), both in the absence and in the presence of 1,000 ng cortisol, it was noted that the inhibition induced by cortisol was of a competitive type and could be overcome by ACTH. This decrease in cortisol was concomitant with an increase in 11-deoxycortisol. Neither corticosterone nor dexamethasone reduced cortisol production. In addition, it was shown that the conversion of tritiated 11-deoxycortisol to radioactive cortisol increased significantly under the influence of 250 pg ACTH (mean relative variation of 21.7% +/- 7.7 (SEM), n = 6, P less than 0.05); but decreased significantly under the combined effect of 1,000 ng exogenous cortisol and the same dose of ACTH: (mean relative variation of 4.3% +/- 1 (SEM), n = 8, P less than 0.005). There is therefore reason to believe that the concentrations of cortisol at the adrenal level modulate the stimulation induced by ACTH and that this self-adjustment forms part of the control mechanisms involved in corticosteroidogenesis.     

In vivo evidence that human adrenal glands possess 11 beta-hydroxysteroid dehydrogenase activity

Blood samples were collected intraoperatorily from inferior vena cava (VC) and adrenal vein (AV) of 8 male and 9 female consenting adult patients undergoing unilateral nephrectomy with ipsilateral adrenalectomy for kidney cancer, and steroid-hormone concentrations were assayed by quantitative HPLC. Hormonal concentrations were significantly higher in AV than in VC (systemic) blood and did not display significant differences between males and females. Higher levels not only of the main glucocorticoids cortisol and corticosterone, but also of their inactive oxidized forms corticosterone and 11-dehydrocorticosterone (DH-B), respectively, were detected in AV than in VC blood. Highly significant inverse correlations between cortisol and cortisone, and corticosterone and DH-B concentrations were observed in AV, but not in VC blood. Moreover, in AV blood the concentration of the main cortisol precursor 11-deoxycortisol correlated inversely with those of both cortisone and DH-B. Taken together, these findings are in keeping with previous in vitro evidence that human adrenal glands possess 11beta-hydroxysteroid dehydrogenase activity, which is engaged in the inactivation of newly formed glucocorticoids and is probably negatively regulated by the local concentrations of non-11beta-hydroxylated steroid-hormone precursors.     

Use of steroid profiles in determining the cause of adrenal insufficiency

HYPOTHESIS: A cortisol response to adrenocorticotropin injection is the standard test for diagnosing adrenal insufficiency. Multiple steroid hormones can now be accurately measured by tandem mass spectrometry in a single sample. The study objective was to determine whether a steroid profile, created by simultaneous measurement of 10 steroid hormones by tandem mass spectrometry, would help determine the cause of adrenal insufficiency. DESIGN: A 10-steroid profile was measured by tandem mass spectrometry during the performance of a standard high dose cortrosyn stimulation test. The steroids were measured at baseline, 30, and 60min following synthetic adrenocorticotropin injection. Adrenal insufficiency was defined as a peak cortisol level of less than 20microg/dL. Testing was conducted in the general clinical research center of a university medical center. Normal volunteers, patients suspected of having adrenal insufficiency, and patients with known adrenal insufficiency participated. RESULTS: Our results showed that adrenal insufficiency of any cause was adequately diagnosed using the response of 11-deoxycortisol, dehydroepiandrosterone, or these analytes combined in a two-steroid profile. A three-steroid profile yielded a test with 100% accuracy for discriminating primary adrenal insufficiency from normal status. Primary adrenal insufficiency was well separated from secondary adrenal insufficiency using only a single aldosterone value. 11-Deoxycortisol, dehydroepiandrosterone, and a two-steroid profile each provided fair discrimination between secondary adrenal insufficiency and normal status. CONCLUSIONS: We conclude that stimulated levels of aldosterone, 11-deoxycortisol, dehydroepiandrosterone, and a two- or three-steroid profile provided additional discrimination between states of adrenal sufficiency and insufficiency. It is proposed that a steroid profile measuring cortisol, aldosterone, 11-deoxycortisol, and dehydroepiandrosterone would potentially improve the ability to determine the cause of adrenal insufficiency.