Steroid glucuronides: Human circulatory levels and formation by LNCaP cells

We studied the relationship between circulating androsterone glucuronide, androstane-3,17β-diol glucuronide and androstane-3β,17β-diol glucuronide concentrations and adrenal as well as testicular C-19 steroids in men. Among the three 5-reduced steroid glucuronides, androsterone glucuronide is the predominant C-19 steroid measured in plasma and its levels are markedly elevated compared to those of the non-conjugated steroid. The marked rise in testosterone during puberty was strongly correlated with the increase in both androsterone glucuronide and androstane-3,17β-diol glucuronide, thus suggesting that testicular C-19 steroids are the main precursors of the steroid glucuronides. We also found that the presence of testicular androgen in plasma contributes to approx. 70% of plasma androsterone glucuronide and androstane-3,17β-diol glucuronide. Our data suggest that the adrenal C-19 steroids remaining in circulation after castration in men are converted into potent androgen which are then glucuronidated by UDP-glucuronyltransferase. We also demonstrated that the human prostate cell line LNCaP is capable of converting to a large extent androstenedione into androsterone glucuronide. Our data further confirm that glucuronidation is a major pathway of steroid metabolism in steroid target tissues.     

Effects of flutamide and aminoglutethimide on plasma 5 alpha-reduced steroid glucuronide concentrations in castrated patients with cancer of the prostate

Plasma levels of androstane-3 alpha, 17 beta-diol glucuronide (3 alpha-diol-G) and androsterone glucuronide (ADT-G) have been found to be effective markers of C-19 steroid metabolism in periphery in man. The present study has been performed in order to study in castrated patients the effect of antiandrogen administered alone or in combination with aminoglutethimide (AG) on the metabolism of adrenal C-19 steroid. Ten castrated patients with prostatic cancer received flutamide (FLU) alone for 2 months and, afterwards, the combined therapy of FLU and AG for 2 months. Antiandrogen treatment alone reduces the levels of dehydroepiandrosterone sulfate (DHEA-S), dehydroepiandrosterone glucuronide (DHEA-G) and androstenedione (4-ene-dione) by 43, 34 and 38% (P less than or equal to 0.01) respectively while dehydroepiandrosterone (DHEA), androst-5-ene-3 beta,17 beta-diol (5-ene-diol) and androst-5-ene-3 beta,17 beta-diol-glucuronide (5-ene-diol-G) levels show a nonsignificant inhibition. In these patients, plasma 3 alpha-diol-G and ADT-G concentrations are nonsignificantly stimulated to 122 and 143%. Moreover, when patients were receiving the combined administration of FLU and AG, adrenal C-19 steroids were further inhibited while both 3 alpha-diol-G and ADT-G show a small but nonsignificant decrease. Our data indicate that the antiandrogen increases the formation and/or the metabolism of adrenal C-19 steroids into steroid glucuronides.     

Precursors of plasma androstanediol- and androgen-glucuronides in women

Although androstanediol (AD) and androstanediolglucuronide (ADG) are generally considered to be parameters of peripheral androgen action, their plasma levels do not always vary in parallel, suggesting that they may have different precursors. Few hard data being available concerning ADG precursors in women, we studied in postmenopausal women with absent or suppressed adrenal function, the blood conversion rates of testosterone (T), dihydrotestosterone (DHT), androstenedione (A) and dehydroepiandrosterone (DHEA) and its sulfate (DHEAS) to AD and ADG respectively, as well as the conversion of AD to ADG. Moreover conversions of these precursors to testosteroneglucuronide (TG) and dihydrotestosteroneglucuronide (DHTG), respectively, were also studied. Our data show that, whereas plasma A and DHT are the major precursors of AD, plasma DHEAS and A are the major precursors of plasma ADG, accounting for 50 and 15%, respectively, of plasma ADG, A being the major precursor of plasma TG and DHTG, respectively. When the conversion rates, obtained in this study, were applied to the plasma concentration of precursors found in normal young and postmenopausal women, respectively, the calculated concentration of product steroids accounted for almost the totality of the actual plasma levels of ADG, TG and DHTG respectively. The difference in relative importance of their precursors, explains that plasma concentrations of AD and ADG do not always vary in parallel; moreover, the importance of DHEAS as precursor of ADG explains the suppression by dexamethasone and the increase after adrenocortical stimulation of plasma ADG levels.     

Androgen glucuronides: I. Direct formation in rat accessory sex organs

A simple one-step procedure is described on the isolation of androgen glucuronides from various rat tissues. This procedure uses polyacrylamide gel electrophoresis, and permits a quantitative isolation of a single band containing the total androgen glucuronides without the contamination of free androgens and androgen sulfates. This procedure was used to determine the ability of various tissues of the rat to form androgen glucuronides directly when they were incubated with 1,2-[³H]-testosterone (0.1 μM) $\text{in}$$\text{vitro}$. Of eleven organs studied, only the accessory sex organs (ventral prostate, seminal vesicle, and coagulating gland), liver, and kidney were capable of forming androgen glucuronides. At the end of a one-hour incubation period, approximately 1% of the total radiolabeled steroids in the prostatic tissue minces were in the form of glucuronide conjugates. The predominant androgen glucuronide formed in the accessory sex organs was 5α-androstane-3α,17β-diol 17β-d-glucuronide. This is in contrast to the rat liver and kidney in which testosterone glucuronide was the predominant conjugate.A similar amount of labeled glucuronide conjugates was formed from either [³H]-testosterone, [³H]-dihydrotestosterone or [³H]-androstenedione, whereas negligible amount of steroid conjugates was formed from [³H]-cortisol. The formation of androgen glucuronides requires metabolically active tissues; furthermore, the conjugation process was inhibited by the antiandrogen, cyproterone acetate, or by metabolic inhibitors, such as oligomycin or N-ethylmaleimide.     

Formation of estrogen glucuronides by human granulosa-luteal cells isolated from human menopausal gonadotropin-stimulated cycles for in vitro fertilization

The formation of steroid glucuronides by human granulosa cells isolated from human menopausal gonadotropin (hMG)/human chorionic gonadotropin (hCG)-stimulated cycles for in vitro fertilization was studied. From granulosa cells in suspension, 5 x 10(-7) M androstenedione was converted into estradiol (2.50 +/- 0.21 ng/ml), estrone (1.84 +/- 0.16 ng/ml), estradiol glucuronide (0.38 +/- 0.07 ng/ml), as well as estrone glucuronide (0.24 +/- 0.04 ng/ml). When 5 x 10(-7) M estradiol was incubated, estrone (15.5 +/- 0.9 ng/ml) and estradiol glucuronide (0.12 +/- 0.05 ng/ml) were detected in medium. Using the same preparation of granulosa cells, we have observed that androsterone could uniquely be transformed into androstane-3 alpha, 17 beta-diol (1.42 +/- 0.56 ng/ml), and only low amounts of steroid glucuronides could be detected. Since the formation of steroid glucuronides was extremely small when granulosa cells in suspension were used, we subsequently studied granulosa cells in culture. When 5 x 10(-7) M estradiol was added, estrone (7.8 +/- 1.3 ng/ml) and estradiol glucuronide (0.68 +/- 0.08 ng/ml) were formed. The addition of follicle-stimulating hormone did not cause a further increase in estrone or estradiol glucuronide levels. As observed with granulosa cells in suspension, incubation with androsterone led to the formation of androstane-3 alpha, 17 beta-diol (24.2 +/- 0.07 ng/ml). Our data demonstrated the presence of glucuronyltransferase in human granulosa cells obtained from preovulatory follicles of hMG/hCG-treated women. In addition, since the conversion of androsterone into C-19 steroid glucoronide was relatively small, the present finding also indicates that the glucoronyltransferase enzymatic activity in granulosa-luteal cells preferentially conjugated estrogens.     

Influence of diet on plasma steroids and sex hormone-binding globulin levels in adult men

Several experimental studies have suggested that diet can alter the production and metabolism of steroids in men. The purpose of this study was to determine the levels of unconjugated steroids and steroid glucuronides as well as sex hormone-binding globulin (SHBG) among normal adult men who were either omnivorous or vegetarians. The participants were white volunteers ranging from 25-35 years of age and the blood samples were taken between 0900 h and 1000 h and between 1600 h and 1700 h for two consecutive days. No significant statistical change was found in plasma dehydroepiandrosterone, dehydroepiandrosterone sulfate, testosterone, dihydrotestosterone and estradiol levels. Vegetarian group showed a higher levels of sex hormone-binding globulin (SHBG) while the free androgen index (FAI; calculated by the ratio testosterone/SHBG) was lower in this group. Although the concentrations of androsterone glucuronide were higher in vegetarian group, the vegetarians had a 25-50% lower level of androstane-3 alpha, 17 beta-diol glucuronide and androstane-3 beta,17 beta-diol glucuronide. Our data further indicate that both, androstane-3 alpha,17 beta-diol glucuronide and androstane-3 beta,17 beta-diol glucuronide concentrations are significantly correlated with SHBG levels and with the FAI values. The increases in androstane-3 alpha,17 beta-diol glucuronide and androstane-3 beta,17 beta-diol glucuronide levels in the omnivorous group are probably a consequence of the elevation of the FAI. Our data suggest that in a vegetarian group, less testosterone is available for androgenic action.     

Hyperinsulinemia and insulin insensitivity in women with nonclassical congenital adrenal hyperplasia due to 21-hydroxylase deficiency: the relationship between serum leptin levels and chronic hyperinsulinemia

BACKGROUND/AIM: Nonclassical congenital adrenal hyperplasia due to 21-hydroxylase deficiency (NC-CAH) is associated with hyperandrogenemia, chronic anovulation, hirsutism, acne and adrenal hyperplasia. A few studies have shown hyperinsulinemia and insulin insensitivity in NC-CAH. Hyperinsulinemia can stimulate leptin secretion, and androgens can inhibit leptin secretion. Thus, we designed a study to investigate the insulin levels and insulin sensitivity and the effect of chronic endogenous hyperinsulinemia and androgens on leptin in patients with NC-CAH. METHODS: Eighteen women with untreated NC-CAH and 26 normally cycling control women with a similar body mass index (BMI) were studied. Basal hormones, fasted and fed insulin levels, leptin and stimulated 17-hydroxyprogesterone (17-OHP) concentrations were studied. Homeostasis model assessment was used to assess insulin sensitivity. RESULTS: The basal 17-OHP, the free testosterone (fT) and dehydroepiandrosterone sulfate (DHEA-S) were significantly different in the 2 groups (p < 0.05). Fasting and fed insulin levels of the NC-CAH group were higher than those of the control group (p < 0.05) and insulin sensitivity was lower in NC-CAH than in controls (p < 0.05). Insulin levels were correlated with fT and 17-OHP (p < 0.05). Serum leptin levels for NC-CAH (25.9 +/- 12.5 microg/l) did not differ from the controls (25.4 +/- 12.06 microg/l) and were positively correlated with BMI (r = 0.725) and percent body fat (r = 0.710) for both groups (both p < 0.001). Leptin levels were not correlated with estrogen or androgens, gonadotropins or insulin levels. CONCLUSION: Hyperinsulinemia and insulin insensitivity associated with hyperandrogenism were detected in untreated NC-CAH patients as in previous reports, whereas serum leptin levels did not differ from those of controls.     

Structure-activity relationship of the cholestatic activity of dihydrotestosterone glucuronide, allo bile acids and lithocholate

Dihydrotestosterone glucuronide (DHTG), a series of 5 alpha-bile acids, or allo-bile acids (3 alpha-hydroxy-5 alpha-cholanic acid, 3-keto-5 alpha-cholanic acid and 3 beta-hydroxy-5 alpha-cholanic acid) and their normal bile acid analogues (3 alpha-hydroxy-5 beta-cholanic acid or lithocholate, 3-keto-5 beta-cholanic acid and 3 beta-hydroxy-5 beta-cholanic acid) were administered intravenously to female rats in order to determine their effects on bile flow. All agents caused a rapid and profound inhibition of bile flow which was dose-dependent. The logarithm of the dose vs the cholestatic response curve for DHTG, the allo-bile acids and lithocholate were all parallel. DHTG was the most potent congener and was two times more potent than 3-keto-5 alpha-cholanic acid and 5 times more potent than lithocholate. These data indicate that the glucuronic acid moiety and the trans configuration of the A and B rings of the steroid nucleus confer the greatest cholestatic potency.     

Enzyme-assisted synthesis and characterization of glucuronide conjugates of neuroactive steroids

Synthesis of reference standards is needed to determine the presence and function of steroid glucuronides in the brain or other tissues, because commercial sources of steroid glucuronide standards are limited or unavailable. In the present study porcine, rat, and bovine liver microsomes were tested to evaluate their ability to glucuronidate eight neurosteroids and neuroactive steroids of various types: dehydroepiandrosterone, pregnenolone, isopregnanolone, 5alpha-tetrahydrodeoxycorticosterone, corticosterone, cortisol, beta-estradiol, and testosterone. In general, the glucuronidation efficiency of rat liver was rather poor compared with that of bovine and porcine liver microsomes. Since porcine liver apparently has a relatively large amount of dehydrogenase, its microsomes also produced dehydrogenated steroids and their glucuronides, as well as various regioisomers in which the site of glucuronidation varied. In contrast, bovine liver microsomes produced mainly a single major glucuronidation product and few dehydrogenation products and gave the best overall yield for two-third of the steroids tested. The enzymatic synthesis of five glucuronides of four steroids was carried out and the conditions, purification, and analytical methods for the glucuronidation products were optimized. The steroid glucuronides synthesized were characterized by nuclear magnetic resonance spectroscopy (NMR) and liquid chromatography-mass spectrometry (LC-MS). The stereochemically pure steroid glucuronide conjugates were recovered in milligram amounts (yield 10-78%) and good purity (>85-90%), which is sufficient for LC-MS/MS method development and analyses of steroid glucuronides in biological matrices such as brain, urine, or plasma.     

Is plasma 5 alpha-androstane 3 alpha, 17 beta-diol glucuronide a biochemical marker of hirsutism in women?

We investigated whether plasma androstanediol glucuronide (ADG) levels reflect the increased androgenicity in women with idiopathic hirsutism (n = 24) or hirsutism associated with polycystic ovary syndrome (n = 10). We also evaluated whether ADG levels parallel the clinical evolution of the hirsutism during a combined treatment, with cyproteroneacetate (2 mg) and ethinylestradiol (35 micrograms), of women with moderate idiopathic hirsutism. Finally, we investigated if there is evidence for increased conversion of precursors to ADG in hirsutism, by comparing the ADG levels, measured by RIA, to ADG levels obtained by applying the conversion rates of precursors obtained in non-hirsute women. ADG levels were increased in less than half of the patients with mild hirsutism. The clinical cure of hirsutism, which was obtained by the treatment in majority of patients, was accompanied by a significant decrease of plasma ADG levels, but a similar decrease was also observed in the 5 patients who did not respond to treatment. The data show that, although there is evidence for increased conversion of precursors to plasma ADG in mildly hirsute women, the latter is not a reliable parameter of androgenicity. Our data suggest, moreover, that treatment with cyproterone acetate and ethinylestradiol decreases 5 alpha-reductase activity, as indicated by the more important decrease in ADG levels than in the precursors.     

Isolation and identification of androstanediol glucuronide from human plasma

[3H]Dihydrotestosterone (50 microCi) was infused into normal men and women for 8 h. It was previously shown that this was sufficient time for this material to reach a steady state. Venous plasma was obtained at 6 and 8 h, pooled, and the unconjugated steroids removed by ether extraction. The remaining plasma was adjusted to pH 4.9 and the steroid conjugate was extracted first with ethyl acetate and then with an ether-ethanol mixture. The extracts were combined and taken to dryness. Steroid sulfates were solvolyzed using dioxane, and the mixture partitioned between ether and 1% NaOH. The aqueous phase was acidified and added to an XAD-2 column, washed with water, and the glucuronide fraction eluted with methanol. The solvent was concentrated and the methanol extract was passed through a C18 Sep-Pak, filtered through an Acrodisc CR and then subjected to gradient high performance liquid chromatography [HPLC] (Nova-Pak C18, KH2PO4, pH 3, and methanol). The fractions containing steroid glucuronides were collected and esterified with diazomethane and then acetylated with acetic anhydride in pyridine. The glucuronide triacetyl methyl ester (GAME) derivatives were then run in a second HPLC system (3 Lichrosorb 5 mu columns, 4 mm x 25 cm) using a gradient of ethanol-heptane and heptane. We clearly established that this system separates 3 alpha-diol GAME conjugated at the 17 and 3 positions (44 vs 50 min) with authentic samples previously synthesized in our laboratory. We concluded that the pooled plasma contained only the 17-GAME conjugate. No significant activity of the 3-glucuronide was detected. The natural compound in circulation, therefore, is 5 alpha-androstane-3 alpha, 17 beta-diol 17-glucuronide.     

Direct high-performance liquid chromatography determination of propofol and its metabolite quinol with their glucuronide conjugates and preliminary pharmacokinetics in plasma and urine of man

Propofol (P) is metabolized in humans by oxidation to 1,4-di-isopropylquinol (Q). P and Q are in turn conjugated with glucuronic acid to the respective glucuronides, propofol glucuronide (Pgluc), quinol-1-glucuronide (Q1G) and quinol-4-glucuronide (Q4G). Propofol and quinol with their glucuronide conjugates can be measured directly by gradient high-performance liquid chromatographic analysis without enzymic hydrolysis. The glucuronide conjugates were isolated by preparative HPLC from human urine samples. The glucuronides of P and Q were present in plasma and urine, P and Q were present in plasma, but not in urine. Quinol in plasma was present in the oxidised form, the quinone. Calibration curves of the respective glucuronides were constructed by enzymic deconjugation of isolated samples containing different concentrations of the glucuronides. The limit of quantitation of P and quinone in plasma are respectively 0.119 and 0.138 μg/ml. The limit of quantitation of the glucuronides in plasma are respectively: Pgluc 0.370 μg/ml, Q1G 1.02 μg/ml and Q4G 0.278 μg/ml. The corresponding values in urine are: Pgluc 0.264 μg/ml, Q1G 0.731 μg/ml and Q4G 0.199 μg/ml. A pharmacokinetic profile of P with its metabolites is shown, and some preliminary pharmacokinetic parameters of P and Q glucuronides are given.     

Androgen glucuronides, instead of testosterone, as the new markers of androgenic activity in women

Despite the long series of cohort studies performed during the last 20 years, the correlation between serum testosterone and any clinical situation believed to be under androgen control in women has remained elusive. This is likely related to the recent finding that the androgens made locally in large amounts in peripheral tissues from the precursor dehydroepiandrosterone (DHEA) act in the same cells where synthesis takes place and are not released in significant amounts in the circulation, thus making unreliable the measurement of serum testosterone as marker of total androgenic activity. The objective is to determine if serum androgen glucuronides can be replaced by testosterone or another steroid as measure of androgenic activity.

Since the glucuronide derivatives of androgens are the obligatory route of elimination of all androgens, these metabolites were measured by liquid chromatography tandem mass spectrometry under basal conditions in 377 healthy postmenopausal women aged 55–65 years as well as in 47 premenopausal women aged 30–35 years while testosterone was assayed by gas chromatography mass spectrometry. No correlation was found between the serum concentration of testosterone and that of androsterone glucuronide (ADT-G) or androstenediol glucuronide (3-diol-G), the androgen metabolites which account for the total pool of androgens.

The present data show that measurement of the total pool of androgens reflected by the serum levels of ADT-G and 3-diol-G cannot be replaced by serum testosterone or any other steroid, including DHEA or DHEA sulphate. These findings may have implications for women with androgen deficiency involving osteoporosis, obesity, type 2 diabetes, sexual dysfunction, loss of muscular strength and a series of other clinical situations affecting women's health. Measuring ADT-G and 3-diol-G might identify cases of true androgen deficiency and provide an opportunity to offer appropriate androgen therapy.     

Identification and quantitation of free and conjugated steroids in milk from lactating women

A method for analysis of metabolic profiles of free and conjugated steroids in milk has been developed. Milk is diluted with aqueous triethylamine sulphate and liquid-solid extraction is achieved on a Sep-Pak C18 cartridge at 60-64 degrees C. Steroids are purified by chromatography on small columns of Lipidex 5000 and sulphohydroxypropyl Sephadex LH-20 [H+] prior to separation into neutral and phenolic compounds, glucuronide, mono- and disulphate conjugate groups on the lipophilic strong anion exchanger triethylaminohydroxypropyl Sephadex LH-20 (TEAP-LH-20). Conjugated steroids are released by enzymatic or solvolytic procedures and separated into a neutral and a phenolic fraction on TEAP-LH-20. The O-methyloxime and trimethylsilyl ether derivatives of the steroids are analyzed by capillary column gas chromatography-mass spectrometry. Fifty steroids were identified in milk collected from women a few days after delivery. Quantitatively about 80% were present as sulphates, 15% as glucuronides and only 5% were unconjugated steroids. The steroid pattern was similar to that in late pregnancy plasma with pregnanolone, pregnanediol and pregnanetriol isomers and dehydroepiandrosterone being predominant. About 10% of the steroid content consisted of estrogens. The total concentration of steroids 2 days after delivery was 20-116 ng/ml, i.e. about 1-5% of the concentration was about 10 ng/ml 1 month after delivery. In one milk sample, collected 2 days after delivery, the steroid concentration (3.6 micrograms/ml) was similar to that in plasma.     

In vivo MRI evaluation of anabolic steroid precursor growth effects in a guinea pig model

Anabolic steroids are widely used to increase skeletal muscle (SM) mass and improve physical performance. Some dietary supplements also include potent steroid precursors or active steroid analogs such as nandrolone. Our previous study reported the anabolic steroid effects on SM in a castrated guinea pig model with SM measured using a highly quantitative magnetic resonance imaging (MRI) protocol. The aim of the current study was to apply this animal model and in vivo MRI protocol to evaluate the growth effects of four widely used over-the-counter testosterone and nandrolone precursors: 4-androstene-3 17-dione (androstenedione), 4-androstene-3β 17β-diol (4-androsdiol), 19-nor-4-androstene-3β-17β-diol (bolandiol) and 19-nor-4-androstene-3 17-dione (19-norandrostenedione). The results showed that providing precursor to castrated male guinea pigs led to plasma steroid levels sufficient to maintain normal SM growth. The anabolic growth effects of these specific precursors on individual and total muscle volumes, sexual organs, and total adipose tissue over a 10-week treatment period, in comparison with those in the respective positive control testosterone and nandrolone groups, were documented quantitatively by MRI.     

Production and secretion of C-19 steroids by rat and guinea pig adrenals

The concentrations of C-19 steroids were measured in guinea pig and rat adrenals before and after castration as well as after stimulation with adrenocorticotropin hormone (ACTH). Characterization of adrenal C-19 steroids was also carried out by isolation with high-performance liquid chromatography and gas chromatography/mass spectrometry (GC/MS). From radioimmunoassay (RIA) data, androstenedione (4-DIONE) and 11 beta hydroxyandrostenedione (11 beta-DIONE) were the major C-19 steroids found in guinea pig adrenals, and castration induced a decrease of 4-DIONE levels only while all other C-19 steroids remained unchanged. In rat adrenals, the major C-19 steroids were 4-DIONE and testosterone, and they were also markedly inhibited after castration. With the exception of 11 beta-DIONE, all other C-19 steroids in circulation were eliminated after castration in both animals species. After ACTH administration in the guinea pig, adrenal 4-DIONE and 11 beta-DIONE levels were markedly stimulated, while an increase of only 11 beta-DIONE was observed in plasma. In the rat, ACTH had a small stimulatory effect on adrenal 52-androstane-3 alpha, 17 beta-diol (3 alpha-DIOL) and plasma 11 beta-DIONE levels. Analysis of guinea pig adrenal steroids by GC/MS confirmed the presence of C-19 steroids in adrenals (namely, 4-DIONE and 11 beta-DIONE) while, in the rat, this could not be confirmed. Our data indicate that production of C-19 steroids occurs in guinea pig adrenals, and 11 beta-DIONE is the major C-19 steroid as well as the only C-19 steroid secreted into the circulation. In the rat, the production of C-19 steroids detected by RIA is not supported by GC/MS data.     

Capillary gas chromatography as a tool for characterization of urinary steroid excretion in patients with congenital adrenal hyperplasia

Urinary steroid excretion was studied by capillary gas chromatography in 23 patients with congenital adrenal hyperplasia. In 5 patients the estimated excretion rates of pregnanetriol were in or below the normal range and 7 patients presented supranormal excretion rates of tetrahydro-cortisone and/or other glucocorticoid metabolites. Deficiency of 21-hydroxylase was nevertheless demonstrated in each patient by an increased ratio of excreted precursors vs products of 21-hydroxylase, e.g. of pregnanetriol/tetrahydro-cortisone. Due to this relative deficiency of glucocorticoids the patients' steroid excretion was further characterized by a predominance of 5 alpha-hydrogenated C19O3 metabolites (11-keto-androsterone, 11-hydroxy-androsterone) over their 5 beta-hydrogenated homologues (11-keto-etiocholanolone, 11-hydroxy-etiocholanolone). An apparent preponderance in the excretion of pregnenetriol over that of pregnanetriol was found in 4 patients, but the presence of pregnenetriol was not confirmed by mass spectrometry following prepurification of the urine samples by thin-layer chromatography indicating interference of an unidentified steroid metabolite with the initial gas chromatographic analysis. The simultaneous determination of steroids serving as precursors or products of 21-hydroxylase by capillary gas chromatography helps to establish the diagnosis of 21-hydroxylase deficiency and to characterize the pattern of steroid excretion in this syndrome even in patients where the estimation of single urinary steroids may lead to erroneous conclusions.     

Increased plasma bile alcohol glucuronides in patients with cerebrotendinous xanthomatosis: effect of chenodeoxycholic acid

Large quantities of C27 bile alcohols hydroxylated at C-25 are excreted in the bile and urine of patients with cerebrotendinous xanthomatosis, a lipid storage disease that results from defective bile acid synthesis. The presence of both biliary and urinary bile alcohols reflects impaired bile acid synthesis. After treatment of samples with beta-glucuronidase, plasma bile alcohols were quantitated by gas-liquid chromatography-mass spectrometry. 5 beta-Cholestane-3 alpha,7 alpha,12 alpha,25-tetrol (334 micrograms/dl) was found to be the major bile alcohol, followed by 5 beta-cholestane-3 alpha,7 alpha,12 alpha,23R,25-pentol (65 micrograms/dl), and 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24(R and S),25-pentols (62.5 micrograms/dl and 64.5 micrograms/dl, respectively) in the plasma of these patients. When compared to biliary and urinary bile alcohol excretions, the plasma pattern resembled bile where 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol glucuronide predominated. In contrast, urinary bile alcohols were composed chiefly of 5 beta-cholestanepentol glucuronides with only small amounts of 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol glucuronide. Treatment with chenodeoxycholic acid, which suppresses abnormal bile acid synthesis in these patients, reduced plasma bile alcohol concentrations dramatically. These results show that large quantities of bile alcohol glucuronides, particularly 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrolglucuronide, circulate in plasma of patients with cerebrotendinous xanthomatosis. The plasma bile alcohols closely resemble biliary bile alcohols which indicates their hepatic origin. The large quantities of polyhydroxylated bile alcohols in the urine may suggest their formation, at least in part, from 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol by renal hydroxylating mechanisms.(ABSTRACT TRUNCATED AT 250 WORDS)