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1.
Steroids ; 73(11): 1066-76, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18502460

RESUMEN

Data are presented on the urinary corticosteroid metabolic profile of the mouse strain 129/svJ. Through the use of GC/MS we have characterized, or tentatively identified corticosterone (Kendall's compound B) metabolites of both the 11beta-hydroxy and 11-carbonyl (compound A) series in urine. Full mass spectra of the methyloxime-trimethylether derivatives of 15 metabolites are included in the paper as an aid to other researchers in the field. Metabolites ranged in polarity from tetrahydrocorticosterone (THB) to dihydroxy-corticosterone with dominance of highly polar steroids. We found that prior to excretion corticosterone can undergo oxidation at position 11beta, reduction at position 20 and A-ring reduction. Metabolites retaining the 3-oxo-4-ene structure can be hydroxylated at position 6beta- as well as at an unidentified position, probably 16alpha-. Saturated steroids can be hydroxylated at positions 1beta-, 6alpha-, 15alpha- and 16alpha. A pair of hydroxy-20-dihydro-corticosterone metabolites (OH-DHB) were the most important excretory products accounting for about 40% of the total. One metabolite of this type was identified as 6beta-hydroxy-DHB; the other, of similar quantitative importance was probably 16alpha-hydroxy-DHB. The ratio of metabolites of corticosterone (B) to those of 11-dehydro-corticosterone (A) was greater than 9:1, considerably higher than that for the equivalent "human" ratio of 1:1 for cortisol to cortisone metabolites. Results from this study allowed the evaluation of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) activity in mice with deleted glucose-6-phosphate transporter (G6PT). These mice had attenuated back-conversion of A to B resulting in an increased ratio of A-metabolites to B-metabolites [Walker EA, Ahmed A, Lavery GG, Tomlinson JW, Kim SY, Cooper MS, Stewart PM, 11beta-Hydroxysteroid dehydrogenase type 1 regulation by intracellular glucose-6-phosphate, provides evidence for a novel link between glucose metabolism and HPA axis function. J Biol Chem 2007;282:27030-6]. We believe this study is currently the most comprehensive on the urinary steroid metabolic profile of the mouse. Quantitatively less steroid is excreted in urine than in feces by this species but urine analysis is more straightforward and the hepatic metabolites are less subject to microbial degradation than if feces was analyzed.


Asunto(s)
Corticosterona/metabolismo , Corticosterona/orina , Glucosa-6-Fosfato/metabolismo , Esteroides/metabolismo , Esteroides/orina , Animales , Corticosterona/análisis , Corticosterona/química , Femenino , Cromatografía de Gases y Espectrometría de Masas , Glucosa-6-Fosfato/deficiencia , Glucosa-6-Fosfato/genética , Hidroxiesteroide Deshidrogenasas/análisis , Hidroxiesteroide Deshidrogenasas/química , Hidroxiesteroide Deshidrogenasas/metabolismo , Hidroxiesteroide Deshidrogenasas/orina , Masculino , Ratones , Ratones Endogámicos , Estructura Molecular , Esteroides/análisis , Esteroides/química
2.
J Clin Invest ; 108(9): 1299-305, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11696574

RESUMEN

Enhanced renal sodium retention and potassium loss in patients with cirrhosis is due to activation of mineralocorticoid receptors (MRs). Increased aldosterone concentrations, however, do not entirely explain the activation of MR in cirrhosis. Here, we hypothesize that cortisol activates MRs in patients with cholestasis. We present evidence that access of cortisol to MRs is a result of bile acid-mediated inhibition of 11 beta-hydroxysteroid dehydrogenase type 2 (11 beta-HSD2), an MR-protecting enzyme that converts cortisol to cortisone. Twelve patients with biliary obstruction and high plasma bile acid levels were studied before and after removal of the obstruction. The urinary ratio of (tetrahydrocortisol + 5 alpha-tetrahydrocortisol)/tetrahydrocortisone, a measure of 11 beta-HSD2 activity, decreased from a median of 1.91 during biliary obstruction to 0.78 at 4 and 8 weeks after removal of the obstruction and normalization of plasma bile acid concentrations. In order to demonstrate that bile acids facilitate access of cortisol to the MR by inhibiting 11 beta-HSD2, an MR translocation assay was performed in HEK-293 cells transfected with human 11 beta-HSD2 and tagged MR. Increasing concentrations of chenodeoxycholic acid led to cortisol-induced nuclear translocation of MR. In conclusion, 11 beta-HSD2 activity is reduced in cholestasis, which results in MR activation by cortisol.


Asunto(s)
Colestasis/enzimología , Fibrosis/metabolismo , Hidroxiesteroide Deshidrogenasas/metabolismo , Hidroxiesteroide Deshidrogenasas/orina , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2 , 11-beta-Hidroxiesteroide Deshidrogenasas , Transporte Activo de Núcleo Celular , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Aldosterona/sangre , Ácidos y Sales Biliares/sangre , Ácidos y Sales Biliares/metabolismo , Línea Celular , Ácido Quenodesoxicólico/sangre , Ácido Quenodesoxicólico/orina , Relación Dosis-Respuesta a Droga , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Hidrocortisona/metabolismo , Riñón/metabolismo , Masculino , Microscopía Fluorescente , Persona de Mediana Edad , Modelos Químicos , Potasio/metabolismo , Sodio/metabolismo , Tetrahidrocortisol/química , Tetrahidrocortisol/orina , Factores de Tiempo , Transfección
3.
Eur J Endocrinol ; 135(2): 238-44, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8810740

RESUMEN

We report the clinical history and results of endocrine investigations in two brothers born to consanguineous parents, who presented with hypokalemia and arterial hypertension when they were aged 2 and 6 years. The hormonal serum assay results, including extremely low values for aldosterone and plasma renin activity, favored the existence of apparent mineralocorticoid excess. A diagnosis of 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) deficiency was made, based on assays of the hydrogenated urinary metabolites of cortisol and cortisone, as well as of corticosterone and dehydrocorticosterone. Indeed we found a very low rate of urinary elimination of cortisone metabolites: tetrahydrogenated cortisone was reduced to between 0.10 and 30 mumol/24 h, which is 15-100 times lower than the normal rate; hexahydrogenated cortolones alpha and beta were found to be 7- to 20-fold lower than normal levels; and the 11-keto-17-ketosteroid derivatives of cortisone were also reduced. Urinary elimination of the cortisol-reduced metabolites 5 beta- and 5 alpha-tetrahydrogenated cortisol were slightly reduced or normal. These results argue in favor of a deficit in the enzyme 11 beta-HSD, which oxidizes cortisol into cortisone. A moderate defect in the conversion of cortisol into 5 beta-THF compared to normal conversion into 5 alpha-THF was also found. With respect to corticosterone metabolism, we demonstrated the presence of a defect in the oxidation of that steroid into dehydrocorticosterone, also due to the deficit in 11 beta-HSD. Arterial hypertension and hypokalemia were corrected by treatment with dexamethasone, concomitantly with correction of the low aldosterone and plasma renin activity levels. On the other hand, during this treatment, urinary concentrations of the metabolites of cortisol, cortisone and corticosterone were only moderately affected.


Asunto(s)
Hidroxiesteroide Deshidrogenasas/deficiencia , Hipertensión/etiología , 11-beta-Hidroxiesteroide Deshidrogenasas , Aldosterona/sangre , Niño , Preescolar , Cortisona/metabolismo , Dexametasona/uso terapéutico , Humanos , Hidrocortisona/metabolismo , Hidroxiesteroide Deshidrogenasas/sangre , Hidroxiesteroide Deshidrogenasas/orina , Hipertensión/tratamiento farmacológico , Masculino , Mineralocorticoides/metabolismo , Renina/sangre
4.
Eur J Clin Invest ; 33(7): 589-94, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12814396

RESUMEN

BACKGROUND: It is unclear whether cortisol production and the 11betaHSD-mediated cortisol to cortisone interconversion are different between type 1 diabetic patients and healthy subjects. MATERIALS AND METHODS: Fourteen male, nonobese, normotensive type 1 diabetic patients without severe complications (HbA1c < 8.5%) were studied twice during a daily sodium intake of 50 and 200 mmol, and were then compared with 14 individually matched healthy subjects. Cortisol production was assessed by the sum of urinary cortisol metabolite excretion. Urinary ratios of (tetrahydrocortisol + allo-tetrahydrocortisol)/tetrahydro-cortisone [(THF + allo-THF)/THE] and of free cortisol/free cortisone [UFF/UFE] were determined as parameters of 11betaHSD activity. RESULTS: Sum of urinary cortisol metabolite excretion during low- and high-salt diet was 7.4 +/- 2.5 vs. 7.7 +/- 2.3 nmol min-1 m-2 (NS) in diabetic patients and 9.7 +/- 2.1 vs. 11.2 +/- 4.1 nmol min-1 m-2 (NS) in healthy subjects, respectively (P < 0.05 vs. healthy subjects at both diets). The allo-THF excretion and allo-THF/THF ratios were lower in the diabetic than in the healthy males during both diets (P < 0.05). Urinary (THF + alloTHF)/THE and UFF/UFE were similar in both groups and remained unchanged after salt loading. CONCLUSIONS: The sum of urinary cortisol metabolite excretion as a measure of cortisol production is lower in nonobese, normotensive type 1 diabetic males with adequate glycaemic control and without severe complications, irrespective of sodium intake. We suggest that this is at least in part as result of diminished 5alpha reductase activity, resulting in a decreased cortisol metabolic clearance. In type 1 diabetic and in healthy males, the 11betaHSD setpoint is not affected by physiological variations in sodium intake.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Hidrocortisona/metabolismo , Hidroxiesteroide Deshidrogenasas/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasas , Adulto , Índice de Masa Corporal , Diabetes Mellitus Tipo 1/orina , Relación Dosis-Respuesta a Droga , Humanos , Hidrocortisona/orina , Hidroxiesteroide Deshidrogenasas/orina , Masculino , Cloruro de Sodio Dietético/administración & dosificación
5.
Endocr Res ; 24(3-4): 659-62, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9888556

RESUMEN

There is growing interest in the hydroxysteroid dehydrogenases (HSDs) as local modulators of hormone action. We have studied urinary steroid profiles from nine men and nine women with Major Depression to determine whether 11beta-HSD and 17beta-HSD activity are altered. Urinary steroid profiles were determined by high resolution gas chromatography. The ratio of 11-oxo over 11beta-hydroxy metabolites of cortisol was used as the index of 11beta-HSD activity and the ratio of dehydroepiandrosterone (DHA) over androstenediol-17beta was used as the index of 17beta-HSD activity. Symptom severity was assessed using the Hamilton Depression Rating Scale (HDRS). None of the measures of cortisol production, 9 AM plasma cortisol, 24 hour urinary free cortisol or 24 hour total urinary cortisol metabolites, correlated with HDRS in either men or women. 11Beta-HSD activity was altered and correlated with symptom severity in depressed women (r=0.688, p<0.05) but not men (r=0.132). In both depressed men and women, 17beta-HSD activity was altered and correlated with HDRS scores (r=-0.796, p<0.05 and r=0.688, p<0.05 respectively). However, although the ratio was changed in the same direction in depressed men and women. the correlation with symptom severity was positive in women but negative in men. We conclude that markers of subtle change such as these may prove more useful and informative than gross changes in plasma cortisol in depression.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas/orina , Depresión/psicología , Depresión/orina , Hidroxiesteroide Deshidrogenasas/orina , Caracteres Sexuales , 11-beta-Hidroxiesteroide Deshidrogenasas , Biomarcadores , Depresión/sangre , Femenino , Humanos , Hidrocortisona/sangre , Hidrocortisona/orina , Masculino , Escalas de Valoración Psiquiátrica , Valores de Referencia
6.
N Engl J Med ; 330(7): 460-5, 1994 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-8289851

RESUMEN

BACKGROUND: Hyperandrogenemia is the hallmark of the polycystic ovary syndrome, yet the relative contributions of the adrenal cortex and ovary to the overproduction of androgen remain unclear. To identify possible causes of adrenocortical overactivity, we studied the metabolism of adrenal and ovarian steroid hormones in women with this disorder. METHODS: We measured 24-hour urinary excretion of steroid hormone metabolites by high-resolution capillary gas chromatography in 65 women with the polycystic ovary syndrome and 45 normal women matched for body-mass index. RESULTS: After adjustment for body-mass index, the urinary excretion of testosterone and androstenedione metabolites was 1.9 times higher in the women with the syndrome than in the normal women, and the excretion of dehydroepiandosterone metabolites (C19 steroid sulfates) and cortisol metabolites was 1.5 and 1.3 times higher, respectively (P < 0.01 for all comparisons). The affected women also had significantly higher ratios of 11-oxo (oxygenated) metabolites to 11-hydroxy metabolites of cortisol (1.4 times higher, P < 0.001) and of 11-oxo to 11-hydroxy metabolites of corticosterone (1.8 times higher, P < 0.001). In the group with the polycystic ovary syndrome, 55 percent of the nonobese women and 24 percent of the obese women had ratios above the upper limit of normal; the ratios in the obese women did not differ significantly from those in the nonobese women. CONCLUSIONS: Adrenal secretion of cortisol and androgens is increased in women with the polycystic ovary syndrome. The increases may be explained by dysregulation of 11 beta-hydroxysteroid dehydrogenase causing increased oxidation of cortisol to cortisone, which cannot be accounted for by obesity.


Asunto(s)
Hidroxiesteroide Deshidrogenasas/metabolismo , Hiperandrogenismo/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasas , Adulto , Femenino , Hormonas/biosíntesis , Hormonas/metabolismo , Humanos , Hidrocortisona/metabolismo , Hidrocortisona/orina , Hidroxiesteroide Deshidrogenasas/orina , Síndrome del Ovario Poliquístico/orina
7.
Hypertension ; 38(6): 1330-6, 2001 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11751713

RESUMEN

Loss-of-function mutations or inhibition of 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD-2) results in overstimulation of the mineralocorticoid receptor by cortisol and causes salt-sensitive hypertension. Traditionally, 11beta-HSD-2 activity has been assessed by measurement of the urinary cortisol metabolite ratio (tetrahydrocortisol [THF]+5alpha-THF)/tetrahydrocortisone (THE). Recently, the ratio of urinary free glucocorticoids, UFF/UFE, has been suggested to be a more reliable parameter, an aspect that has not been investigated systematically. Steroid metabolites were measured repeatedly by gas chromatography-mass spectrometry in 20 healthy subjects at baseline and after 1 week each of a 30- or 180-mmol/d of sodium diet or 500 mg/d of glycyrrhetinic acid. Intraindividual coefficients of variation from 3 random urine collections for (THF+5alpha-THF)/THE and UFF/UFE ratios were 11+/-9% and 25+/-14% (P<0.001). (THF+5alpha-THF)/THE was more sensitive than UFF/UFE for detection of glycyrrhetinic acid-induced increases higher than the upper 95% confidence interval of the coefficient of variation of the corresponding ratio. Low- or high-salt diet did not alter either ratio. Mean (THF+5alpha-THF)/THE but not UFF/UFE was higher in salt-sensitive than salt-resistant subjects. Absolute glycyrrhetinic acid-related increase in (THF+5alpha-THF)/THE but not UFF/UFE was higher in salt-sensitive than salt-resistant subjects and correlated with changes in mean BP. Intraindividual variability of (THF+5alpha-THF)/THE is lower than that of UFF/UFE. The UFF/UFE ratio does not appear to be more sensitive than (THF+5alpha-THF)/THE for detection of decreased 11beta-HSD-2 activity. The (THF+5alpha-THF)/THE ratio better discriminates between salt-sensitive and salt-resistant subjects. Together with BP responses to glycyrrhetinic acid, these findings support a pivotal role of 11beta-HSD-2 in salt sensitivity.


Asunto(s)
Presión Sanguínea/fisiología , Ácido Glicirretínico/farmacología , Glycyrrhiza , Hidroxiesteroide Deshidrogenasas/orina , Sodio en la Dieta/administración & dosificación , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2 , Adulto , Presión Sanguínea/efectos de los fármacos , Electrólitos/sangre , Femenino , Predisposición Genética a la Enfermedad , Ácido Glicirretínico/sangre , Humanos , Masculino , Estudios Prospectivos , Tetrahidrocortisol/orina , Tetrahidrocortisona/orina
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