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1.
Science ; 214(4521): 659-60, 1981 Nov 06.
Article in English | MEDLINE | ID: mdl-6945674

ABSTRACT

Plasma cholesterol sulfate concentration is increased in patients with recessive X-linked ichthyosis, a disease in which steroid sulfatase activity is absent. In these patients, cholesterol sulfate is found primarily in the low-density lipoprotein fraction of plasma, and the electrophoretic mobility of these lipoproteins is greatly increased.


Subject(s)
Cholesterol Esters/blood , Ichthyosis/genetics , Lipoproteins, LDL/blood , Electrophoresis, Agar Gel , Female , Genes, Recessive , Genetic Linkage , Humans , Ichthyosis/blood , Steryl-Sulfatase , Sulfatases/deficiency , Sulfates , X Chromosome
2.
Steroids ; 73(11): 1066-76, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18502460

ABSTRACT

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.


Subject(s)
Corticosterone/metabolism , Corticosterone/urine , Glucose-6-Phosphate/metabolism , Steroids/metabolism , Steroids/urine , Animals , Corticosterone/analysis , Corticosterone/chemistry , Female , Gas Chromatography-Mass Spectrometry , Glucose-6-Phosphate/deficiency , Glucose-6-Phosphate/genetics , Hydroxysteroid Dehydrogenases/analysis , Hydroxysteroid Dehydrogenases/chemistry , Hydroxysteroid Dehydrogenases/metabolism , Hydroxysteroid Dehydrogenases/urine , Male , Mice , Mice, Inbred Strains , Molecular Structure , Steroids/analysis , Steroids/chemistry
3.
J Clin Invest ; 82(1): 340-9, 1988 Jul.
Article in English | MEDLINE | ID: mdl-3164727

ABSTRACT

The first adult case of 11 beta-hydroxysteroid dehydrogenase (11 beta-OHSD) deficiency is described. The impaired conversion of cortisol to cortisone (indicated by urinary cortisol and cortisone metabolites and failure to metabolize 11 alpha-[3H]cortisol to [3H]H2O), was associated with hypertension, hypokalemia, and suppression of the renin-angiotensin-aldosterone system. When established on a fixed Na+/K+ intake, dexamethasone, given orally, produced a natriuresis and potassium retention. Plasma renin activity became detectable. When hydrocortisone (10 mg daily s.c. for 4 d) was added, there was marked Na+ retention, a kaliuresis (urinary Na+/K+ falling from 1.2 to 0.15), with suppression of plasma renin activity and an increase in blood pressure. These changes were also seen with the subject on no treatment. Conversion of cortisone to cortisol was not affected. These results suggest that cortisol acts as a potent mineralocorticoid in 11 beta-OHSD deficiency. The major site for the oxidation of cortisol to cortisone is the kidney. In this patient congenital deficiency of 11 beta-OHSD results in high intrarenal cortisol levels which then act on renal type I mineralocorticoid receptors. This condition can be treated with dexamethasone, which suppresses cortisol secretion and binds to the type II glucocorticoid receptor. We suggest that 11 beta-OHSD exerts a critical paracrine role in determining the specificity of the type I receptor. In the normal state cortisol is converted by 11 beta-OHSD to cortisone which thus allows aldosterone to bind preferentially to the type I receptors in the kidney and gut. In this patient deficiency of 11 beta-OHSD results in high intrarenal cortisol concentrations that then bind to the type I receptor.


Subject(s)
Cortisone/metabolism , Hydrocortisone/metabolism , Hydroxysteroid Dehydrogenases/deficiency , Mineralocorticoids/metabolism , 11-beta-Hydroxysteroid Dehydrogenases , Adolescent , Adult , Alkalosis/enzymology , Alkalosis/genetics , Cortisone/analogs & derivatives , Dexamethasone , Hemodynamics , Humans , Hydrocortisone/blood , Hydroxysteroid Dehydrogenases/genetics , Hypertension/enzymology , Hypertension/genetics , Hypokalemia/enzymology , Hypokalemia/genetics , Male , Middle Aged , Syndrome
4.
J Clin Invest ; 87(5): 1841-52, 1991 May.
Article in English | MEDLINE | ID: mdl-2022750

ABSTRACT

Direct measurement of de novo lipogenesis has not previously been possible in humans. We measured de novo hepatic lipogenesis in normal men by means of stable isotopes and by combining the acetylated-xenobiotic probe technique with mass isotopomer analysis of secreted very low density lipoprotein-fatty acids (VLDL-FA). Sulfamethoxazole (SMX) was administered with [13C]acetate during an overnight fast followed by refeeding with intravenous glucose (7-10 mg/kg of weight per min), oral Ensure (7-10 mg of carbohydrate/kg of weight per min), or a high-carbohydrate mixed-meal breakfast (3.5 g of carbohydrate/kg of weight). Respiratory quotients remained less than 1.0. High-performance liquid chromatography/mass spectrometry-determined enrichments in SMX-acetate attained stable plateau values, and hepatic acetyl-coenzyme A (CoA) dilution rate did not increase with refeeding (approximately 0.024 mmol/kg per min). The fraction of VLDL-palmitate derived from de novo lipogenesis was only 0.91 +/- 0.27% (fasted) and 1.64-1.97% (fed). For stearate, this was 0.37 +/- 0.08% and 0.47-0.64%. Precursor enrichments predicted from isotopomer ratios were close to measured SMX-acetate enrichments, indicating that SMX-acetate samples the true lipogenic acetyl-CoA pool. Stearate synthesis was less than palmitate and the two did not move in parallel. Estimated total VLDL-FA synthesis is less than 500 mg/day. Thus, de novo hepatic lipogenesis is a quantitatively minor pathway, consistent with gas exchange estimates; fatty acid futile cycling (oxidation/resynthesis) is not thermogenically significant; and synthesis rates of different nonessential fatty acids by human liver are not identical in nonoverfed normal men. The contribution and regulation of de novo lipogenesis in other settings can be studied using this technique.


Subject(s)
Lipids/biosynthesis , Liver/metabolism , Acetyl Coenzyme A/analysis , Calorimetry , Carbon Isotopes , Fasting , Fatty Acids/metabolism , Humans , Lipoproteins, VLDL/metabolism , Male , Mathematics , Models, Biological , Sulfamethoxazole/metabolism
5.
Cancer Res ; 50(17): 5488-96, 1990 Sep 01.
Article in English | MEDLINE | ID: mdl-2386954

ABSTRACT

We established a continuous cell line, NCI-H295, from an invasive primary adrenocortical carcinoma. The cell line was established in a fully defined medium (HITES) and later could be adapted for growth in a simple medium supplemented only with selenium, insulin, and transferrin and devoid of serum, steroids, fibroblast growth factor, and a source of exogenous cholesterol. NCI-H295 cells had a relatively long population doubling time and were tumorigenic when inoculated s.c. into athymic nude mice. The cultured cells had ultrastructural features of steroid-secreting cells and contained complex cytogenetic abnormalities including the presence of multiple marker chromosomes. Steroid analyses (radioimmunoassays and mass spectrometry), performed 7 to 9 years after culture initiation, demonstrated secretion of more than 30 steroids characteristic of adrenocortical cells. Total unconjugated steroid secretion in serum-supplemented medium was 2.83 micrograms/10(6) cells/24 h and about 4-fold less in serum-free medium. The major pathway of pregnenolone metabolism in NCI-H295 cells is androgen synthesis, with formation of dehydroepiandrosterone, androstenedione, testotesterone, and at least three sulfated androgens, as well as estrogens. In addition, formation of cortisol, corticosterone, aldosterone, and 11 beta-hydroxyandrostenidione indicated the presence of 11 beta-hydroxylase. Thus, multiple pathways of steroidogenesis are expressed by NCI-H295 cells, including formation of corticosteroids, mineralocorticoids, androgens, and estrogens. Our findings indicate the presence in NCI-H295 cells of all of the major adrenocortical enzyme systems, including 11 beta-hydroxylase, desmolase, 21 alpha-hydroxylase, 17 alpha-hydroxylase, 18-hydroxylase, lyase, sulfokinase, and aromatase. The NCI-H295 cell line should prove of value in studying the regulation, metabolic pathways, and enzymes involved in steroid formation and secretion. In addition, it may provide insights into the biology and treatment of adrenocortical carcinoma.


Subject(s)
Adrenal Cortex Neoplasms/pathology , Steroids/metabolism , Tumor Cells, Cultured/cytology , Adrenal Cortex Neoplasms/genetics , Adrenal Cortex Neoplasms/metabolism , Adrenal Cortex Neoplasms/ultrastructure , Animals , Cell Line , Chromatography, High Pressure Liquid , Chromosome Banding , Culture Techniques/methods , Humans , Karyotyping , Mass Spectrometry , Mice , Mice, Nude , Microscopy, Electron , Steroids/biosynthesis , Transplantation, Heterologous
6.
Mol Endocrinol ; 11(13): 1961-70, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9415400

ABSTRACT

The secosteroid hormone, 1,25-dihydroxyvitamin D [1,25(OH)2D], plays a crucial role in normal bone growth, calcium metabolism, and tissue differentiation. The key step in the biosynthesis of 1,25(OH)2D is its 1 alpha-hydroxylation from 25-hydroxyvitamin D (25-OHD) in the kidney. Because its expression in the kidney is very low, we cloned and sequenced cDNA for 25-OHD-1 alpha-hydroxylase (P450c1 alpha) from human keratinocytes, in which 1 alpha-hydroxylase activity and mRNA expression can be induced to be much greater. P450c1 alpha mRNA was expressed at much lower levels in human kidney, brain, and testis. Mammalian cells transfected with the cloned P450c1 alpha cDNA exhibit robust 1 alpha-hydroxylase activity. The identity of the 1,25(OH)2D3 product synthesized in transfected cells was confirmed by HPLC and gas chromatography-mass spectrometry. The gene encoding P450c1 alpha was localized to chromosome 12, where the 1 alpha-hydroxylase deficiency syndrome, vitamin D-dependent rickets type 1 (VDDR-1), has been localized. Primary cultures of human adult and neonatal keratinocytes exhibit abundant 1 alpha-hydroxylase activity, whereas those from a patient with VDDR-1 lacked detectable activity. Keratinocyte P450c1 alpha cDNA from the patient with VDDR-1 contained deletion/frameshift mutations either at codon 211 or at codon 231, indicating that the patient was a compound heterozygote for two null mutations. These findings establish the molecular genetic basis of VDDR-1, establish a novel means for its study in keratinocytes, and provide the sequence of the key enzyme in the biological activation of vitamin D.


Subject(s)
25-Hydroxyvitamin D3 1-alpha-Hydroxylase/genetics , Chronic Kidney Disease-Mineral and Bone Disorder/enzymology , Chronic Kidney Disease-Mineral and Bone Disorder/genetics , Cloning, Molecular , Mutation , 25-Hydroxyvitamin D3 1-alpha-Hydroxylase/physiology , Amino Acid Sequence , Animals , Base Sequence , Cell Line , Cells, Cultured , Chronic Kidney Disease-Mineral and Bone Disorder/congenital , DNA, Complementary/biosynthesis , DNA, Complementary/isolation & purification , Female , Humans , Infant , Keratinocytes , Leydig Cells , Male , Mice , Molecular Sequence Data , Organ Specificity/genetics , RNA, Messenger/biosynthesis
7.
J Invest Dermatol ; 80(6): 514-6, 1983 Jun.
Article in English | MEDLINE | ID: mdl-6304199

ABSTRACT

Patients with recessive X-linked ichthyosis lack activity of the enzyme steroid sulfatase. One of the more striking clinical findings in these patients is the improvement in stratum corneum shedding in the summer. Since vitamin D is one steroid responsive to sunlight, we examined whether or not vitamin D3 sulfate is a substrate for steroid sulfatase. Enzyme preparations active against other sulfated steroids caused no desulfation of vitamin D3 sulfate.


Subject(s)
Cholecalciferol/metabolism , Sulfatases/metabolism , Humans , Ichthyosis/physiopathology , Microsomes/enzymology , Skin/physiopathology , Steryl-Sulfatase , Sulfatases/deficiency
8.
Endocrinology ; 129(6): 2941-50, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1954879

ABSTRACT

The present studies were conducted to define the pathway(s) by which androstenedione is metabolized in porcine granulosa cells (pGC) and determine whether metabolism of this steroid is affected by in vitro luteinization. pGC isolated from large preovulatory follicles were cultured for up to 2 days in the presence of 5 microM unlabeled or [4-14C]-labeled androstenedione. Metabolism of androstenedione was assessed by HPLC, using in-line liquid scintillation detection. Metabolite identification was confirmed by gas chromatography-mass spectrometry of HPLC fractions isolated from medium conditioned by granulosa cells (pGCCM) cultured for 48 h in the presence of unlabeled androstenedione. The metabolites identified were 19-oic-androstenedione (3,17-dioxo-4-androsten-19-oic acid), 19-hydroxytestosterone, 19-hydroxyandrostenedione, 19-nor-testosterone, an estrenolone of as yet unproven stereoisomerism, 5(10)-estrene-3 beta, 17 beta-diol, 17 beta-estradiol, testosterone, and 19-nor-androstenedione. Results indicate that 19-nor-androstenedione is artifactually derived from 19-oic-androstenedione as a result of degradation in storage and during isolation. After metabolite identification, studies of the time course of androstenedione metabolism by pGC during in vitro luteinization were conducted. 17 beta-Estradiol and 19-oic-androstenedione were the predominant metabolites, and accumulation of these steroids was virtually identical. Production of these metabolites was maximal during the first 12 h of culture. The accumulation of 5(10)-estrene-3 beta,17 beta-diol and 19-nor-testosterone was maximal at 48 h of culture, with 5(10)-estrene-3 beta,17 beta-diol consistently accumulating in greater concentrations than 19-nor-testosterone. Aromatase activity of pGC was negligible from 36-48 h of culture, as demonstrated by minimal accumulation of 17 beta-estradiol during this period of culture. The accumulation of 19-oic-androstenedione, 5(10)-estrene-3 beta,17 beta-diol, and 19-nor-testosterone was also negligible during this latter time period, suggesting that their formation is associated with aromatase. From these results, pGC from preovulatory follicles undergoing luteinization in vitro lose the ability to convert androstenedione to estrogens. The formation of 19-oic-androstenedione, shown here for the first time, parallels the formation of 17 beta-estradiol, and this acidic steroid is proposed to be a product of aromatase. As reported in previous studies, pGC do produce C18 neutral steroids from exogenous androstenedione. The production of these steroids requires an active aromatase to produce their immediate precursor, which is here hypothesized to be 19-oic-androstenedione. However, their maximal production does not commence until aromatase activity has declined, and it is hypothesized that their production depends on modifications in steroid metabolism associated with luteinization.


Subject(s)
Androgens/metabolism , Androstenedione/analogs & derivatives , Corpus Luteum/physiology , Granulosa Cells/metabolism , Androstenedione/metabolism , Animals , Cells, Cultured , Chromatography, High Pressure Liquid , Estradiol/metabolism , Female , Gas Chromatography-Mass Spectrometry , Kinetics , Swine
9.
Endocrinology ; 110(2): 384-9, 1982 Feb.
Article in English | MEDLINE | ID: mdl-7056205

ABSTRACT

The formation of 19-hydroxydeoxycorticosterone (19,21-dihydroxy-4-pregnen-3,20-dione), 19-oxo-deoxycorticosterone (21-hydroxy-4-pregnen-3,19,20-trione), and 19-oic-deoxycorticosterone (19-oic-21-hydroxy-4-pregnen-3,20-dione) from precursor deoxycorticosterone by adrenal glands obtained from intact rats and from rats undergoing adrenal regeneration was demonstrated. These metabolites were isopolar with corresponding authentic steroid standards on thin layer chromatography, gas chromatography, and high pressure liquid chromatography. They were further characterized by either mass spectrometry or gas chromatography-mass spectrometry. Therefore, rat adrenals have the enzymes required to convert deoxycorticosterone to 19-hydroxydeoxycorticosterone, 19-oxo-deoxycorticosterone, and 19-oic-deoxycorticosterone; however, rat adrenals do not convert deoxycorticosterone or any of the oxygenated metabolites to 19-nor-deoxycorticosterone (21-hydroxy-19-nor-4-pregnen-3,20-dione). It is possible, however, that 19-nor-deoxycorticosterone is formed at peripheral sites from the oxygenated deoxycorticosterone precursors.


Subject(s)
Adrenal Glands/metabolism , Desoxycorticosterone/analogs & derivatives , Desoxycorticosterone/metabolism , Animals , Desoxycorticosterone/isolation & purification , Gas Chromatography-Mass Spectrometry , Rats , Rats, Inbred Strains
10.
Endocrinology ; 145(5): 2157-64, 2004 May.
Article in English | MEDLINE | ID: mdl-14962994

ABSTRACT

The gonadal and placental paralogues of porcine aromatase cytochrome P450 (P450arom) were examined for novel catalytic properties to shed light on the evolutionary survival of duplicated copies of an enzyme critical to reproduction. Recombinant gonadal P450arom catalyzed the formation of a novel metabolite from testosterone, identified by gas chromatography/mass spectrometry and biochemical analyses as 1 beta-hydroxytestosterone (1 beta OH-T), in almost equal proportion to 17beta-estradiol (E(2)). This activity was absent in reactions with the porcine placental paralogue (or other orthologues) of P450arom and was minimal with androstenedione. Incubations with both porcine enzymes and with bovine and human P450arom demonstrated that 1 beta OH-T was not aromatizable, and 1 beta OH-T activated the androgen receptor of prostate cancer cells in vitro. Porcine testicular and follicular granulosa tissues synthesized 1 beta OH-T, which was also detected in testicular venous plasma. These results constitute the first of identification of a novel, perhaps potent, nonaromatizable metabolite of testosterone, whose synthesis (paradoxically) can be definitively ascribed to the activity of the gonadal paralogue of porcine P450arom. It probably represents an evolutionary gain of function associated with fixation and the survival of the genes after CYP19 duplication. Novel activities and adaptive functions may exist among other duplicated vertebrate aromatases.


Subject(s)
Aromatase/genetics , Aromatase/metabolism , Gene Duplication , Animals , Cattle , Estradiol/metabolism , Evolution, Molecular , Female , Gas Chromatography-Mass Spectrometry , Humans , Hydroxytestosterones/metabolism , Isoenzymes/genetics , Isoenzymes/metabolism , Kinetics , Male , Ovary/enzymology , Placenta/enzymology , Pregnancy , Recombinant Proteins , Substrate Specificity , Swine , Testis/enzymology , Testosterone/metabolism , Tritium
11.
J Clin Endocrinol Metab ; 81(11): 3855-60, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8923828

ABSTRACT

We describe two female siblings who had production of cortisol (F; as determined from excretion of urinary metabolites) high enough to give rise to Cushing's disease, but who had no clinical indications of the condition. The teenage patients were hirsute as a result of adrenal hyperandrogenism. A notable feature of the condition was the elevated excretion of corticosteroid metabolites with 11-carbonyl groups and very low excretion of 11 beta-hydroxylated steroids. We termed this disorder apparent cortisone (E) reductase disorder. The steroid metabolite phenotype appeared to be the opposite of that seen in the apparent mineralocorticoid excess syndrome, in which the excretion of 11-keto compounds is attenuated. As an example, the tetrahydrocortisol plus 5 alpha-tetrahydrocortisol/tetrahydrocortisone ratio was about 0.04 compared to normal values of about 1.0 and apparent mineralocorticoid excess syndrome values of 5.0-50.0. Paradoxically, among the F metabolites that had not undergone A-ring reduction, 11 beta-hydroxylated steroids dominated over 11-carbonyl compounds. The F/E ratio was about 1.8 compared to an average normal value of 0.54. Neither the father nor the mother of the patient had abnormal F metabolite/E metabolite ratios, although the father did excrete highly elevated free E and F, possibly an unrelated condition. A conclusion was not reached regarding the basis of the disorder. We considered that the most likely causes were 1) defective hepatic 11 beta-hydroxysteroid dehydrogenase-1, 2) failure to develop the adult form of F metabolism, or 3) excessive activity of A ring reduction enzymes acting on E.


Subject(s)
Adrenocortical Hyperfunction/enzymology , Hydrocortisone/biosynthesis , Hydroxysteroid Dehydrogenases/deficiency , 11-beta-Hydroxysteroid Dehydrogenases , Adolescent , Adrenal Cortex Hormones/metabolism , Adrenocortical Hyperfunction/etiology , Adrenocortical Hyperfunction/metabolism , Adult , Androgens/biosynthesis , Cortisone/biosynthesis , Cortisone/metabolism , Female , Hirsutism/enzymology , Hirsutism/etiology , Hirsutism/metabolism , Humans , Hydrocortisone/metabolism , Hydroxysteroid Dehydrogenases/metabolism , Liver/enzymology , Male , Phenotype
12.
J Clin Endocrinol Metab ; 48(6): 976-82, 1979 Jun.
Article in English | MEDLINE | ID: mdl-312808

ABSTRACT

[4-14C]Corticosterone was administered to a woman with the 17 alpha-hydroxylase deficiency syndrome and urine was collected for 72 h. Sixty-three percent of the radioactivity was eliminated on the first day, 10.3% on the second, and 3.8% on the third, making a total recovery of 77%. On the first day, 85% of the recovered radioactivity was in the glucuronide conjugates of corticosterone, 10.6% was in the sulfate form of this steroid, and 3.9% was in the free forms of the steroid. On the following 2 days, the proportion of labeled glucuronides and free steroids decreased and that of labeled sulfates increased. On the first day of collection, the major radiolabeled metabolites were 21-hydroxylated steroids (e.g. allo-tetrahydrocorticosterone and 5 alpha- and beta-pregnane-3 alpha,11 beta,20 alpha,21-tetrol), but by the third day, at least 75% of the excreted activity was associated with 21-deoxysteroids, such as 3 alpha,20 alpha-dihydroxy-5 alpha (and beta)-pregnan-11-one and 5 alpha- and beta-pregnane-3 alpha,11 beta,20 alpha-triol. Bacterial metabolism in the intestinal tract is responsible for the dehydroxylation. 6 alpha-Hydroxytetrahydrocorticosterone was tentatively identified among several new metabolites of corticosterone.


Subject(s)
Adrenal Hyperplasia, Congenital , Corticosterone/urine , Steroid Hydroxylases/deficiency , Adult , Chromatography, Gas , Female , Humans , Mass Spectrometry , Steroids/urine
13.
J Clin Endocrinol Metab ; 59(3): 513-20, 1984 Sep.
Article in English | MEDLINE | ID: mdl-6086702

ABSTRACT

We documented 17-hydroxylase deficiency in a newborn male infant with micropenis, perineoscrotal hypospadias, and a bifid scrotum containing two histologically normal testes. Mild hypertension developed at 20 months of age. The diagnosis was made on the basis of elevated serum levels of progesterone (180-475 ng/dl), corticosterone (1.8-20.2 micrograms/dl), and desoxycorticosterone (56-330 ng/dl). There was an exaggerated response of these steroids to ACTH-(1-24) and suppression by dexamethasone. Mass spectrometric analysis of urinary steroids showed an abnormally high ratio of C21 to C19 3 beta-hydroxy-5-ene steroids due to reduced C19 steroid formation. We suggest that this infant has a form of 17-hydroxylase deficiency which is less severe than previously reported cases in view of his partial prenatal virilization, the minimal testosterone response to CG the absence of hypokalemia, and the presence of normal cortisol levels after prolonged ACTH stimulation. Family studies suggest reduced 17-hydroxylase activity in the father. A surprising coincident finding of no apparent clinical significance was in vitro evidence of 5 alpha-reductase deficiency in genital skin fibroblasts.


Subject(s)
Adrenal Hyperplasia, Congenital , Steroid Hydroxylases/deficiency , 3-Oxo-5-alpha-Steroid 4-Dehydrogenase/deficiency , Adrenal Cortex Hormones/blood , Adrenocorticotropic Hormone , Female , Genitalia, Male/metabolism , Gonadal Steroid Hormones/blood , Humans , In Vitro Techniques , Infant , Infant, Newborn , Male
14.
J Clin Endocrinol Metab ; 54(2): 325-31, 1982 Feb.
Article in English | MEDLINE | ID: mdl-7033278

ABSTRACT

The salt-losing syndromes in the neonatal period and early infancy due to adrenal disease can be differentiated by the pattern of excretion of steroids in urine. The presence or absence of metabolites of cortisol, aldosterone, and corticosterone as well as certain precursors can be established in a single analysis of steroids in urine by using gas chromatography with open tubular capillary columns. The profiles of steroid excretion in the urine of 8 infants with renal tubular insensitivity to aldosterone were compared with those in 5 infants with isolated aldosterone biosynthetic defects. The excretion in urine of 18 hydroxytetrahydro-compound A was elevated in all 13 children, but relative to the excretion of tetrahydroaldosterone, a high ratio was found for the biosynthetic defect and clearly distinguished the 2 conditions. Age-related changes in steroid metabolism are described. The diagnosis in each case was supported by clinical investigation together with determinations of PRA and aldosterone concentrations.


Subject(s)
Aldosterone/biosynthesis , Corticosterone/urine , Hydrocortisone/urine , Metabolism, Inborn Errors/urine , Renal Tubular Transport, Inborn Errors/urine , Aldosterone/analogs & derivatives , Aldosterone/urine , Child, Preschool , Chromatography, Gas , Diagnosis, Differential , Female , Humans , Infant , Infant, Newborn , Male , Renin/blood , Sodium/urine , Sodium Chloride/urine , Syndrome
15.
J Clin Endocrinol Metab ; 84(3): 1157-9, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10084612

ABSTRACT

The equine-type estriols 1,3,5(10),7-estratetraene-3,16alpha,17beta-triol (16alpha-hydroxy-17beta-dihydroequilin) and 1,3,5(10),6,8-estrapentaene-3,16alpha,17beta-triol (16alpha-hydroxy-17beta-dihydroequilenin) constituted over half of the estrogens excreted by a woman carrying a Smith-Lemli-Opitz syndrome (SLOS) affected fetus. The steroids were characterized by gas chromatography-mass spectrometry (GC/MS), and mass spectra of the dehydro estriols as trimethylsilyl ethers are illustrated. SLOS is associated with 7-dehydrocholesterol (7DHC), delta 7-reductase deficiency; the enzyme catalyzing the final step in cholesterol biosynthesis. Identification of these equine estrogens show that an estrogen biosynthetic pathway parallel to normal is functional in the feto-placental unit and uses 7DHC as precursor, therefore P450scc, P450c17, and 3betaHSD and P450arom are all active on 7-dehydrometabolites. Patients with affected fetuses have low plasma estriol values (probably due to deficient production of the cholesterol precursor) and this is often a warning sign which instigates further evaluation for SLOS. The estriol deficiency is not quantitatively made up by the dehydrometabolites, and the combined excretion was found to be about one-third of the mean of gestational age matched controls. The importance of these findings lies in the potential value of dehydroestriol measurement for non-invasive diagnosis of SLOS at mid-gestation. Currently diagnosis relies on imaging, since SLOS is a malformation syndrome, and measurement of 7DHC levels in amniotic fluid and chorionic villus tissue.


Subject(s)
Estriol/urine , Horses/metabolism , Pregnancy/urine , Smith-Lemli-Opitz Syndrome/embryology , Adult , Animals , Female , Humans
16.
J Clin Endocrinol Metab ; 76(3): 559-65, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8445011

ABSTRACT

We measured de novo lipogenesis in human immunodeficiency virus (HIV) infected men using a newly developed stable isotope method. HIV-infected subjects with a history of weight loss (n = 17, mean weight loss 14.9 +/- 3.2 kg), asymptomatic HIV-seropositive subjects with normal CD4 T-cell counts (n = 7) and healthy HIV seronegative controls (n = 11) were studied. Hepatic lipogenesis was determined by infusion of [2-13C]-acetate, using the recently described xenobiotic probe technique with mass isotopomer analysis. Hepatic acetyl-coenzyme A enrichment was measured by high performance liquid chromatography/mass spectrometry of secreted sulfamethoxazole-acetate, with measurement of incorporation into very low density lipoprotein-fatty acids by gas chromatography-mass spectrometry. Circulating tumor necrosis factor (TNF), interleukin-1 (IL-1), interferon alpha (IFN alpha), insulin, and triglycerides were measured concurrently, and 7-day weighed food records were performed. De novo hepatic lipogenesis was increased 3- to 4-fold in HIV-infected subjects with weight loss compared to normal controls (P < 0.05 for palmitate and stearate in both overnight-fasted and fed states), and was also significantly increased in asymptomatic HIV seropositive subjects. Circulating TNF and IL-1 were not measurable in any subject (detection limit 2 pg/ml for IL-1 and 20 pg/ml for TNF). Serum IFN alpha was measurable in 11 out of 17 subjects with wasting and correlated significantly with de novo lipogenesis in overnight-fasted but not fed states. Serum IFN alpha was unmeasurable in asymptomatic HIV-infected subjects despite elevated lipogenic rates. Serum triglyceride concentrations were elevated in subjects with weight loss (2.09 +/- 0.28 mmol/L) and asymptomatic HIV-positives (1.34 +/- 0.34 mmol/L) in comparison to controls (0.67 +/- 0.08 mmol/L), and correlated with lipogenesis. Food intake correlated inversely with lipogenesis in the overnight-fasted state. We conclude that HIV infection is characterized by abnormal fat anabolism. This applies to subjects with reduced lean body mass and to asymptomatic HIV-positive subjects with normal T-cell counts. The former observation may have implications for the pathophysiology and treatment of the wasting syndrome. The latter observation is consistent with activation of the immune response and a state of viral nonlatency in early HIV disease.


Subject(s)
HIV Infections/metabolism , Lipids/biosynthesis , Liver/metabolism , Adult , Body Composition , Cytokines/blood , Energy Intake , HIV Infections/blood , HIV Infections/physiopathology , Humans , Insulin/blood , Male , Osmolar Concentration , Triglycerides/blood
17.
J Clin Endocrinol Metab ; 76(3): 748-51, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8445034

ABSTRACT

11 beta-Hydroxysteroid dehydrogenase (11 beta HSD), found predominantly in liver and kidney, is responsible for the shuttling of active cortisol to cortisone. A defect in this shuttle mechanism, e.g. after liquorice ingestion, results in an increase in the ratio of urinary cortisol [tetrahydrocortisol (THF)] to cortisone [tetrahydrocortisone (THE)] metabolites. The plasma cortisol half-life is prolonged, but concentrations remain normal because of a concomitant fall in cortisol production. Alcohol-induced pseudo-Cushing's syndrome is an ill defined cause of Cushing's syndrome. Because many of the documented cases have abnormal liver function tests, we have investigated whether abnormal hepatic 11 beta HSD activity may play a role in the pathogenesis of the condition. Fourteen patients with alcoholic (ALD) and 14 patients with non-alcoholic (CLD) chronic liver disease had marked deficiency of 11 beta HSD [5 alpha-THF + THF/THE: ALD, 1.94 +/- 0.38 (+/- SEM); CLD, 1.82 +/- 0.20] compared to controls (0.94 +/- 0.04; P < 0.01 and 0.001, respectively). In the CLD group, the daily cortisol production rate (as assessed by summation of principal cortisol metabolites) was reduced appropriately [median, 3,510; range, 1,101-8,940 micrograms/24 h; controls, 5,492 (range, 3,818-14,996) micrograms/24 h; P < 0.001], and normal 0900 h plasma cortisol and urinary free cortisol levels were maintained. However, in the ALD group, there was no concomitant fall in the cortisol production rate (sum of cortisol metabolites, 5,043 micrograms/24 h; range, 520-27,344). As a consequence, 0900 h plasma cortisol in the ALD group was significantly elevated (633 +/- 52 nmol/L) compared to values in the CLD group (487 +/- 48 nmol/L; P < 0.05) and controls (432 +/- 27 nmol/L; P < 0.001). Our findings of glucocorticoid excess in patients with chronic ALD may indicate that alcohol-induced pseudo-Cushing's syndrome develops as a result of continuing normal cortisol secretion in the face of impaired cortisol metabolism. The latter is mediated by defective hepatic 11 beta HSD activity; the former by either abnormal glucocorticoid feedback or stimulation of cortisol secretion at the level of the hypothalamus/pituitary.


Subject(s)
Hydrocortisone/metabolism , Hydroxysteroid Dehydrogenases/deficiency , Liver Diseases, Alcoholic/enzymology , Liver Diseases, Alcoholic/urine , Liver Diseases/enzymology , Liver Diseases/urine , 11-beta-Hydroxysteroid Dehydrogenases , Adult , Chronic Disease , Female , Humans , Hydrocortisone/blood , Hydrocortisone/urine , Male , Middle Aged
18.
J Clin Endocrinol Metab ; 75(1): 195-200, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1619010

ABSTRACT

We have developed a gas chromatographic/mass spectral method for the sensitive and reproducible measurement of estradiol-17-fatty acid esters in human tissues and blood. To provide an internal standard for quantification, a trideuterated analog of a representative estradiol ester is added to the tissues. Estradiol (E2) released from the nonpolar ester fraction by alkaline hydrolysis is derivatized to form the ditrimethylsilyl ether and then analyzed by gas chromatographic/mass spectral, monitoring the molecular ions mass per U charge of the ditrimethylsilyl derivative of E2 and [2H3]E2. There are low but detectable levels of E2 ester in the blood of cycling females; there are none in urine. While the E2 ester is present in breast cyst fluid, its concentration, 77-140 pmol/L, is considerably less than E2, 110-2,863 pmol/L. But there is a large amount of E2 ester in fat. In premenopausal women the average E2 ester in fat (sc and omental) is 957 +/- 283 38 fmol/g (SEM); in women who are menopausal less than 12 yr, the E2 ester in fat is 669 +/- 158 fmol/g; in women who are menopausal at least 15 yr, the fat level is 399 +/- 146 fmol/g. Muscle from the same women have lower concentrations of the ester; in 8 out of 12 muscle specimens it was not detectable. The E2 esters are extremely potent estrogens. Although they are hormonally active they require enzymatic hydrolysis to exert their hormonal action. These studies show that these long chain esters of E2 are sequestered in fatty tissues, wherein they represent a protected store of preformed hormone. Under the proper stimulation, adipose tissue can activate the estrogenic signal through the action of hormonally sensitive esterases. Thus, through signaling between estrogen sensitive tissues and neighboring fat cells, a local paracrine loop may exist.


Subject(s)
Estradiol/analogs & derivatives , Fatty Acids/analysis , Adipose Tissue/chemistry , Adult , Estradiol/analysis , Estradiol/blood , Estradiol/urine , Exudates and Transudates/chemistry , Fatty Acids/blood , Fatty Acids/urine , Female , Fibrocystic Breast Disease/chemistry , Gas Chromatography-Mass Spectrometry/methods , Humans , Menopause , Muscles/chemistry , Tissue Distribution
19.
J Clin Endocrinol Metab ; 50(4): 786-02, 1980 Apr.
Article in English | MEDLINE | ID: mdl-6988456

ABSTRACT

A 4-yr-old boy with hypertension and hypokalaemic alkalosis had low plasma aldosterone levels and renin activity. The hypertension and hypokalemia responded to spironolactone and triamterene therapy. A partial response to dexamethasone was observed. Analysis of urinary steroid metabolites by gas chromatography-mass spectrometry showed that the excretion of metabolites of deoxycorticosterone and aldosterone was subnormal, and there was no evidence for sizeable excretion of unusual steroids with potential mineralocorticoid activity. The cortisol excretion rate, however, was subnormal, and the relative excretions of individual metabolites of this hormone were not typical. In particular, the excretion of tetrahydrocortisone was markedly reduced, and the excretions of allotetrahydrocortisol and free cortisol and metabolites were elevated. These findings suggest that modified or deficient metabolism of adrenal steroids could give rise to elevated blood pressure. It is not known whether the inappropriate production of unusual cortisol metabolites were responsbile for the high blood pressure or whether the altered metabolism is indicative of similar abnormality in the metabolism of other adrenal steroids, resulting in hyperproduction or extended half-life of minor but highly active mineralocorticoids of unknown structures.


Subject(s)
Alkalosis/metabolism , Hypertension/metabolism , Liver/metabolism , Steroids/urine , Aldosterone/blood , Alkalosis/complications , Child, Preschool , Gas Chromatography-Mass Spectrometry , Humans , Hypertension/complications , Hypertension/drug therapy , Male , Renin/blood , Spironolactone/therapeutic use , Triamterene/therapeutic use
20.
J Clin Endocrinol Metab ; 49(2): 247-51, 1979 Aug.
Article in English | MEDLINE | ID: mdl-156733

ABSTRACT

Congenital adrenal hypoplasia is reported in two siblings. The first died at 16 months of purulent bronchopneumonia after a history of adrenal insufficiency. No gross adrenal tissue was found at autopsy and urinary steroids were not excreted in detectable amounts before death. In a subsequent uncomplicated pregnancy, extremely low estrogens were recorded in the last trimester. Analysis of steroids in the urine of the neontate by gas chromatography revealed virtual absence of 3 beta-hydroxy-5-ene steroids. These suggest hypoplasia of the fetal adrenal cortex. Metabolites of cortisol were excreted in normal amounts and responded adequately to ACTH stimulation. Neonatal hyponatremia was associated with subnormal excretion of corticosterone and aldosterone metabolites. It is proposed that in the perinatal period, the fetal zone is required for mineralocorticoid synthesis, possibly by providing essential precursor steroids, e.g. 21-hydroxypregnenolone.


Subject(s)
Adrenal Insufficiency/congenital , Dehydroepiandrosterone/urine , Adrenal Insufficiency/drug therapy , Adrenal Insufficiency/urine , Chromatography, Gas , Dehydroepiandrosterone/analogs & derivatives , Dexamethasone/therapeutic use , Fludrocortisone/therapeutic use , Humans , Infant , Infant, Newborn , Male
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