Amino Acids and Lipids Associated with Long-Term and Short-Term Red Meat Consumption in the Chinese Population: An Untargeted Metabolomics Study.

Red meat (RM) consumption is correlated with multiple health outcomes. This study aims to identify potential biomarkers of RM consumption in the Chinese population and evaluate their predictive ability. We selected 500 adults who participated in the 2015 China Health and Nutrition Survey and examined their overall metabolome differences by RM consumption by using elastic-net regression, then evaluate the predictivity of a combination of filtered metabolites; 1108 metabolites were detected. In the long-term RM consumption analysis 12,13-DiHOME, androstenediol (3α, 17α) monosulfate 2, and gamma-Glutamyl-2-aminobutyrate were positively associated, 2-naphthol sulfate and S-methylcysteine were negatively associated with long-term high RM consumption, the combination of metabolites prediction model evaluated by area under the receiver operating characteristic curve (AUC) was 70.4% (95% CI: 59.9-80.9%). In the short-term RM consumption analysis, asparagine, 4-hydroxyproline, and 3-hydroxyisobutyrate were positively associated, behenoyl sphingomyelin (d18:1/22:0) was negatively associated with short-term high RM consumption. Combination prediction model AUC was 75.6% (95% CI: 65.5-85.6%). We identified 10 and 11 serum metabolites that differed according to LT and ST RM consumption which mainly involved branch-chained amino acids, arginine and proline, urea cycle and polyunsaturated fatty acid metabolism. These metabolites may become a mediator of some chronic diseases among high RM consumers and provide new evidence for RM biomarkers.

A Metabolome-Wide Study of Dry Eye Disease Reveals Serum Androgens as Biomarkers.

PURPOSE: To test the association between serum metabolites and dry eye disease (DED) using a hypothesis-free metabolomics approach. DESIGN: Cross-sectional association study. PARTICIPANTS: A total of 2819 subjects from the population-representative TwinsUK cohort in the United Kingdom, with a mean age of 57 years (range, 17-82 years). METHODS: We tested associations between 222 known serum metabolites and DED. All subjects underwent nontargeted metabolomic analysis of plasma samples using gas and liquid chromatography in combination with mass spectrometry (Metabolon Inc., Durham, NC). Dry eye disease was defined from the validated Short Questionnaire for Dry Eye Syndrome (SQDES) as a previous diagnosis of DED by a clinician or "often" or "constant" symptoms of dryness and irritation. Analyses were performed with linear mixed effect models that included age, BMI, and sex as covariates, corrected for multiple testing. MAIN OUTCOME MEASURES: Primary outcome was DED as defined by the SQDES, and secondary outcomes were symptom score of DED and a clinical diagnosis of DED. RESULTS: Prevalence of DED as defined by the SQDES was 15.5% (n = 436). A strong and metabolome-wide significant association with DED was found with decreased levels of the metabolites androsterone sulfate (P = 0.00030) and epiandrosterone sulfate (P = 0.00036). Three other metabolites involved in androgen metabolism, 4-androsten-3beta,17beta-diol disulfate 1 and 2, and dehydroepiandrosterone sulfate, were the next most strongly associated of the 222 metabolites, but did not reach metabolome-wide significance. Dryness and irritation symptoms, as opposed to a clinical diagnosis, were particularly strongly associated with decreased androgen steroid metabolites, with all reaching metabolome-wide significance (androsterone sulfate, P = 0.000000029; epiandrosterone sulfate, P = 0.0000040; 4-androsten-3beta,17beta-diol disulfate 1, P = 0.000016; 4-androsten-3beta,17beta-diol disulfate 2, P = 0.000064; and dehydroepiandrosterone sulfate, P = 0.00011). Of these 5 androgens, epiandrosterone sulfate (P = 0.0076) was most associated with 2-year incidence of clinician-diagnosed DED. In addition, we found decreased glycerophosphocholines to be associated with DED, although not at metabolome-wide significance. CONCLUSIONS: This hypothesis-free metabolomic approach found decreased serum androgens to be highly associated with DED and adds important evidence to the growing body of research that links androgens to ocular surface disease and DED.

Neuroactive Steroids in Acute Ischemic Stroke: Association with Cognitive, Functional, and Neurological Outcomes.

Despite several scientific and technological advances, there is no single neuroprotective treatment that can reverse the brain damage after acute ischemic stroke (AIS). Neuroactive steroids are cholesterol-derived hormones that have the ability to modulate the normal and pathologic nervous system employing genomic and nongenomic mechanisms. In this work, we first investigated if AIS affects the plasma concentration of 5 neuroactive steroids (cortisol, estradiol, progesterone, testosterone, and 3α-androstenediol glucuronide). Second, we studied if levels of circulating steroids associate with neurological, cognitive, and functional outcome in a cohort of 60- to 90 year-old male and female patients with AIS. For this purpose, we recruited patients who were hospitalized at the Emergency Room of the Central Military Hospital within the first 24 h after stroke onset. We designed 2 experimental groups, each one composed of 30 control subjects and 30 AIS patients, both males and females. The assessment of neurological deficit was performed with the NIHSS and the tests used for the functional and cognitive status were: (1) modified Rankin Scale; (2) Photo test, and (3) abbreviated Pfeiffer's mental status questionnaire. We observed a significant difference in plasma concentration of cortisol and estradiol between both experimental groups. In the AIS group, higher levels of these neuroactive steroids were associated with more pronounced neurological, cognitive and functional deficits in women compared to men. We propose that in elderly patients, high levels of circulating neuroactive steroids like cortisol and estradiol could potentiate AIS-mediated neuropathology in the ischemic and penumbra areas.

Gas chromatography-mass spectrometry method for the analysis of 19-nor-4-androstenediol and metabolites in human plasma: application to pharmacokinetic studies after oral administration of a prohormone supplement.

19-Nor-4-androstenediol is a prohormone of nandrolone. Both substances are included in the WADA list of prohibited classes of substances. The aim of this study is to determine the plasma levels of 19-nor-4-androstenediol and its metabolites after oral administration of a nutritional supplement containing the drug. Two capsules of Norandrodiol Select 300 were orally administered to six healthy male volunteers. Plasma samples were collected up to 24h. Samples were extracted to obtain free and glucuronoconjugated metabolic fractions. Trimethylsilyl derivatives of both fractions were analyzed by gas chromatography coupled to mass spectrometry (GC-MS). The method was validated to determine linearity, extraction recovery, limit of detection and quantification, intra- and inter-day precision and accuracy. After administration of 19-nor-4-androstenediol, the main metabolites detected were norandrosterone and noretiocholanolone, mainly in the glucuronide fraction. Nandrolone, norandrostenedione and 19-nor-4-androstenediol were also detected at lower concentrations.

Endogenous sex hormones and prostate cancer: a collaborative analysis of 18 prospective studies.

BACKGROUND: Sex hormones in serum have been hypothesized to influence the risk of prostate cancer. We performed a collaborative analysis of the existing worldwide epidemiologic data to examine these associations in a uniform manner and to provide more precise estimates of risks. METHODS: Data on serum concentrations of sex hormones from 18 prospective studies that included 3886 men with incident prostate cancer and 6438 control subjects were pooled by the Endogenous Hormones and Prostate Cancer Collaborative Group. Relative risks (RRs) of prostate cancer by fifths of serum hormone concentration were estimated by use of conditional logistic regression with stratification by study, age at recruitment, and year of recruitment. All statistical tests were two-sided. RESULTS: No associations were found between the risk of prostate cancer and serum concentrations of testosterone, calculated free testosterone, dihydrotestosterone, dehydroepiandrosterone sulfate, androstenedione, androstanediol glucuronide, estradiol, or calculated free estradiol. The serum concentration of sex hormone-binding globulin was modestly inversely associated with prostate cancer risk (RR in the highest vs lowest fifth = 0.86, 95% confidence interval = 0.75 to 0.98; P(trend) = .01). There was no statistical evidence of heterogeneity among studies, and adjustment for potential confounders made little difference to the risk estimates. CONCLUSIONS: In this collaborative analysis of the worldwide data on endogenous hormones and prostate cancer risk, serum concentrations of sex hormones were not associated with the risk of prostate cancer.

Quantitative determination of metabolic products of 19-norandrostenediol in human plasma using gas chromatography/mass spectrometry.

Prohormones such as 19-norandrostenediol (estr-4-ene-3beta,17beta-diol) have been added to the list of prohibited substances of the World Anti-Doping Agency because they are metabolized to the common nandrolone metabolites norandrosterone and noretiocholanolone. So far, no studies on the metabolism and in vivo conversion of 19-norandrostenediol after oral or sublingual administration have been reported nor have had quantified data on resulting plasma nandrolone levels. In the present study, an open-label crossover trial with eight healthy male volunteers was conducted. After application of capsules or sublingual tablets of 19-norandrostenediol plasma concentrations of 19-norandrostenediol, nandrolone as well as major metabolites (19-norandrosterone and 19-noretiocholanolone) were determined using a validated assay based on gas chromatography/mass spectrometry. The administration of 100-mg capsules of 19-norandrostenediol yielded maximum plasma total concentrations (i.e., conjugated plus unconjugated compounds) of 1.1 ng/ml (+/-0.7) for 19-norandrostenediol, 4.0 ng/ml (+/-2.6) for nandrolone, 154.8 ng/ml (+/-130.8) for 19-norandrosterone, and 37.7 ng/ml (+/-6.9) for 19-noretiocholanolone. The use of 25-mg sublingual tablets resulted in 3.3 ng/ml (+/-1.0) for 19-norandrostenediol, 11.0 ng/ml (+/-6.4) for nandrolone, 106.3 ng/ml (+/-40.1) for 19-norandrosterone, and 28.5 ng/ml (+/-20.8) for 19-noretiocholanolone. Most interestingly, the pharmacologically active unconjugated nandrolone was determined after administration of sublingual tablets (up to 5.7 ng/ml) in contrast to capsule applications. These results demonstrate the importance of prohibiting prohormones such as 19-norandrostenediol, in particular, since plasma concentrations of nandrolone between 0.3 to 1.2 ng/ml have been reported to influence endocrinological parameters.

Phase I and clinical pharmacology of a type I and II, 5-alpha-reductase inhibitor (LY320236) in prostate cancer: elevation of estradiol as possible mechanism of action.

OBJECTIVES: To study the safety, pharmacokinetics, biologic activity, and preliminary efficacy of the bispecific 5-alpha-reductase inhibitor (LY320236) in prostate cancer. METHODS: Fifty-one patients with recurrent or metastatic prostate cancer were sequentially (nonrandomly) assigned in cohorts to receive one of five single daily oral doses of LY320236 (10, 50, 150, 250, and 500 mg). Serial evaluations included serum testosterone, dihydrotestosterone, androstenediol glucuronide, estradiol, and pharmacokinetics on days 1, 29, and 57. Toxicity assessments, x-rays/scans, and blood tests, including serum prostate-specific antigen (PSA) determination, were done at regular intervals. RESULTS: Overall, treatment was well tolerated, with 3 of 51 patients developing reversible grade 3-4 toxicity (one diarrhea, two elevated liver enzymes). Peak blood levels (2 to 3 hours after drug administration) were greater for doses of 150 mg or greater compared with less than 150-mg doses with slow accumulation. Serum levels of testosterone, dihydrotestosterone, and androstenediol glucuronide did not change significantly during treatment; however, a statistically significant increase occurred in serum estradiol levels in both the castration and noncastration groups. One of 26 in the noncastration group and 4 (27%) of 15 in the castration group with baseline PSA levels of 5 ng/mL or greater had a 50% or greater PSA decline for 4 weeks or longer. CONCLUSIONS: LY320236 treatment is associated with modest reversible toxicity. An elevation of estradiol levels was seen in both castration and noncastration groups, although PSA declines were primarily seen in the castration group. The absence of cardiovascular toxicity suggests that this agent may be a promising alternative to exogenous estrogens in patients with prostate cancer who demonstrate evidence of disease progression after initial androgen deprivation treatment.

Simultaneous determination of androstenediol 3-sulfate and dehydroepiandrosterone sulfate in human serum using isotope diluted liquid chromatography-electrospray ionization-mass spectrometry.

A simple method for simultaneous determination of androstenediol 3-sulfate (Adiol-3S) and dehydroepiandrosterone sulfate (DHEA-S) in human serum using isotope diluted liquid chromatography-electrospray ionization-ion trap-mass spectrometry (LC-ESI-ion trap-MS) was developed. After addition of deuterated internal standards ([2H5]Adiol-3S and [2H4]DHEA-S), human serum (100 microl) was deproteinized with acetonitrile and then applied to a solid-phase extraction cartridge, Oasis HLB. The obtained steroid sulfates fraction was washed with hexane and then analyzed by LC-ESI-MS operated in the negative ion mode. The quantification ranges of Adiol-3S and DHEA-S were 10-400 ng/ml and 0.05-8 microg/ml, respectively. The method does not require the chemical or enzymatic hydrolysis of the conjugates and purification with high-performance liquid chromatography, and shows satisfactory reproducibility and accuracy. The concentrations of these sulfates in the sera of healthy male volunteers (n=14) were 19.2-245.3 mg/ml (Adiol-3S) and 0.175-5.16 microg/ml (DHEA-S), and those of patients with prostate cancer (n=19) were 15.3-182.7 ng/ml (Adiol-3S; four samples, not detectable) and 0.110-2.421 microg/ml (DHEA-S).

Adrenal androgen production in response to adrenocorticotropin infusions in men.

The responses of several adrenal steroids to adrenocorticotropin (ACTH) were investigated in a group of healthy young men. The protocol consisted of overnight adrenal suppression with dexamethasone followed by 1 hr infusions of ACTH in increasing (4X) doses ranging from 30-30,720 ng/1.5M2 followed by 0.25 mg ACTH/1.5M2. Whereas cortisol, androstenedione and androstenediol concentrations tended to plateau at the higher ACTH infusion rates, those of dehydroepiandrosterone (DHEA) and 17-hydroxyprogesterone (17-OH P) did not. The cortisol concentration achieved after the highest dose of ACTH was over 50 fold higher than that at baseline. DHEA levels rose to values about 13 times baseline whereas the other steroids increased to lesser extents (3-5 fold). The ACTH infusion rate required to significantly increase each steroid over the baseline level was extrapolated from dose response curves and was considered to be an index of the sensitivity of each steroid to ACTH. Cortisol was the most sensitive, rising significantly at approximately 35 ng ACTH/1.5M2, followed by androstenediol, DHEA, androstenedione and 17-OH P.

Serum 5-androstene-3 beta,17 beta-diol sulphate and 5 alpha-androstane-3 alpha,17 beta-diol sulphate in hirsute females with polycystic ovarian disease.

Serum sulphates of 5-androstene-3 beta,17 beta-diol (5-ADIOL-S), 5 alpha-androstane-3 alpha,17 beta-diol (3 alpha-DIOL-S) and dehydroepiandrosterone (DHEA-S), unconjugated androstene-dione (AD) and testosterone (T), sex hormone binding globulin (SHBG), free androgen index (FAI), 17 alpha-hydroxyprogesterone (17OHP), luteinising hormone (LH) and follicle stimulating hormone (FSH) were measured by specific radioimmunoassay in 28 hirsute women with polycystic ovarian disease (PCO) and in normal women (n = 73). Mean levels of steroids measured were significantly elevated, and SHBG significantly depressed, in the women with PCO with values (mean +/- SE) for 5-ADIOL-S (516 +/- 51 vs 267 +/- 10 nmol/l), 3 alpha-DIOL-S (130 +/- 9 vs 52 +/- 2 nmol/l), DHEA-S (7.3 +/- 0.5 vs 4.4 +/- 0.2 mumol/l), AD (11.3 +/- 1.1 vs 3.4 +/- 0.2 nmol/l), T (3.3 +/- 0.2 vs 1.5 +/- 0.1 nmol/l) and 17OHP (5.1 +/- 0.8 vs 2.8 +/- 0.2 nmol/l). SHBG levels were 31 +/- 2.9 vs 65 +/- 2.5 nmol/l, and the free androgen index [100 x T (nmol/l) divided by (SHBG nmol/l)] was 12.5 +/- 1.4 vs 2.4 +/- 0.1. The mean LH to FSH ratio was also elevated at 2.8 +/- 0.3. These studies suggest that the measurement of 5-ADIOL-S and DHEA-S may indicate adrenal gland involvement in PCO while 3 alpha-DIOL-S appears to be a reflection of peripheral androgen metabolism. A comprehensive biochemical profile of PCO should thus include the analysis of these sulphoconjugates as well as unconjugated steroids.

Serum 5-androstene-3 beta,17 beta-diol sulphate, sex hormone binding globulin and free androgen index in girls with premature adrenarche.

Serum sex hormone binding globulin (SHBG), testosterone (T), DHEA sulphate (DHEA-S), androstenedione (AD) and delta 5-androstene-3 beta,17 beta-diol sulphate (5-ADIOL-S) levels were measured by specific radioimmunoassay in 16 girls presenting with premature adrenarche (PA) and in 14 normal girls. Mean levels of steroids measured were elevated, and SHBG significantly depressed, in the girls with PA, with values (mean +/- SE) for DHEA-S (1.73 +/- 0.17 vs 0.25 +/- 0.06 mumol/l), 5-ADIOL-S (104 +/- 8 vs 31 +/- 4 nmol/l), AD (0.89 +/- 0.06 vs 0.62 +/- 0.04 nmol/l), and T (0.49 +/- 0.03 vs 0.23 +/- 0.06 nmol/l). SHBG levels were 68 +/- 6 vs 108 +/- 5 nmol/l, and the free androgen index [100 x T (nmol/l) divided by SHBG (nmol/l)] was 0.89 +/- 0.17 vs 0.22 +/- 0.01. These studies show that SHBG is depressed in girls with premature adrenarche; with the increased testosterone levels, this results in a markedly elevated free androgen index, a measure of testosterone which is bioavailable to target tissue. This may be compounded by the elevated levels of 5-ADIOL-S in girls with PA since its role may be as a prohormone for more potent androgens (testosterone, 5 alpha-dihydrotestosterone) in target tissues such as pubic skin.

[Analysis of experimental autoimmune oophoritis as a model of premature ovarian failure].

Neonatal thymectomy in mice at 3 days of age (Tx-3) can induce autoimmune oophoritis and results in complete loss of oocyte at young adult age. We examined endocrinological and immunological abnormalities in Tx-3 (C3H/He X A/J)F1 female mice to find some similarities to premature ovarian failure (POF) in humans. The majority of the Tx-3 mice showed irregular estrous cycles during 7 to 9 weeks of age then fell into continuous diestrous. Endocrinological analysis of Tx and sham-Tx mice revealed that serum gonadotropin levels (LH and FSH) of Tx-3 mice rapidly increased from 8 weeks of age and serum estradiol levels significantly decreased from 10 weeks of age (P less than 0.05). In contrast with estradiol, serum androstenedione levels significantly increased from 10 weeks of age (P less than 0.01). In the mice with oophoritis, circulating autoantibodies against ooplasm and/or zona pellucida determined by immunoperoxidase method could be detected from 6 weeks of age, became high titer from one or two weeks later, but resulted in low titer or negative test from about 4 months of age. Acute loss of oocyte with massive mononuclear cell infiltration coincident with the appearance of these autoantibodies were progressed, and then atrophic ovaries with complete destruction of follicles were seen at 3 months of age. This experimental model of autoimmune oophoritis abounds in suggestion for the understanding of one of the possible etiology of POF in women.

[Determination of 5 alpha-androstane-3 alpha, 17 beta-diol in human serum by GC-SIM and influence of age-associated change].

5 alpha-Androstane-3 alpha, 17 beta-diol (A3 alpha diol) is a potent androgen, and is an end product of testosterone. Many authors measured A3 alpha diol levels in human plasma by various methods, but the levels of this steroid were very dissimilar. In order to validate such values, it was measured by gas chromatography-selected ion monitoring (GC-SIM) in this study. A3 alpha diol, 5 alpha-Androstane-3 beta, 17 beta-diol (A3 beta diol) and Testosterone (T) in human peripheral serum were measured by GC-SIM at the same time. The TFA-derivatives of these compounds were analyzed after purification of the serum extract by Sephadex LH-20 microcolumn chromatography. The sensitivity was good: (16.7 pg/ml: A3 alpha diol, 26.7 pg/ml: A3 beta diol). The precision (CV = 2.75%: A3 alpha diol, 3.11%: A3 beta diol) and the accuracy were better than ever reported. Serum A3 alpha diol was measured in 131 healthy men aged 15-81 years and 5 healthy women aged 25-60 years. There were remarkable differences between individuals in the serum levels of A3 alpha diol, but the levels in male serum (greater than 20y) showed a significant negative correlation with age (r = -0.560, p less than 0.01). When these healthy men were classified into three age groups of 20-39, 40-59 and 60-79 years, the values (mean +/- SD) for serum A3 alpha diol were 189.3 +/- 77.7 (n = 20), 127.9 +/- 59.5 (n = 28), and 94.9 +/- 52.9 (n = 73) pg/ml, respectively. There were significant differences between the levels of this steroid in all age groups (p less than 0.01). There was a weak but significant correlation between serum A3 alpha diol and T levels (r = 0.3235, p less than 0.01) in healthy men (25-77 years, n = 77). Determination of serum A3 alpha diol was influenced by age. The number of samples strongly influenced the decision of mean value of A3 alpha diol levels. These results suggested that these factors had to be made obvious when this steroid was studied.

The use of nonradiolabelled steroid infusions to investigate the origin of oestrone sulphate in postmenopausal women.

Infusion of nonradiolabelled dehydroepiandrosterone sulphate (DHA-S) has been used to investigate the possible formation of oestrone sulphate via a sulphated conjugate of androstenedione. The metabolic clearance rate (MCR) of DHA-S also was measured and the mean value (25 1/24h) was similar to values reported using isotopic techniques. Although conversion of DHA-S to 5-androstenediol, a steroid with oestrogenic properties, was detected during infusion of DHA-S, there were no significant increases in plasma levels of conjugated androstenedione or oestrone sulphate. The MCR's oestrone sulphate measured using infusion of nonradiolabelled steroid in two menopausal women were 99 1/24h and 121 1/24h. For one woman, the production rate of oestrone sulphate, calculated from the conversion of oestrone and oestradiol to oestrone sulphate (151 nmol/day) was similar to the measured production rate of oestrone sulphate (144 nmol/day). It is concluded that in menopausal women, oestrone sulphate is derived from conversion of oestrone and oestradiol with no formation occurring via conjugated androstenedione.

Concentration patterns of plasma dehydroepiandrosterone, delta 5-androstenediol and their sulphates, testosterone and cortisol in normal healthy women and in women with anorexia nervosa.

Plasma levels of cortisol, dehydroepiandrosterone (DHA), dehydroepiandrosterone sulphate (DHAS), delta 5-androstenediol (delta 5-DIOL), delta 5-androstenediol sulphate (delta 5-DIOL-S) and testosterone were determined every 2 h from 10.00 to 20.00 h in 8 normal women and 10 with anorexia nervosa. Plasma levels of cortisol. DHA and delta 5-DIOL were significantly (P less than 0.001) higher while DHAS levels were significantly (P less than 0.001) lower in the anorexic women. The levels of delta 5-DIOL-S and testosterone were similar in both groups of women. In the normal women there were significant (P less than 0.001) diurnal fluctuations in the levels of cortisol, DHA and DHAS with high levels in the morning and a nadir in the evening; however, there were significant P less than 0.001) 'reverse' diurnal fluctuations in the levels of delta 5-DIOL, delta 5-DIOL-S and testosterone with low levels in the morning and elevated levels in the evening. In the anorexia nervosa women there was a loss of the diurnal variation in the levels of cortisol, DHA and DHAS and delta 5-DIOL-S; the diurnal variations of delta 5-DIOL and testosterone levels in the anorexic women were similar to those in the normal women. In general, these findings support the suggestion of a disturbance in the mechanisms regulating hypothalamic-pituitary-adrenal function resulting from a primary hypothalamic defect and/or abnormal alterations in steroid metabolism associated with the malnutrition in anorexia nervosa.

The interrelationship between plasma 5-ene adrenal androgens in normal women.

Plasma concentrations of 5-androstene-3 beta,17 beta-diol (ADIOL) dehydroepiandrosterone (DHA) dehydroepiandrosterone sulphate (DHAS) and cortisol were measured by radioimmunoassay in a group of women aged between 27 and 88 years of age. There was a significant negative correlation with increased age for all three adrenal androgens but not for cortisol. The decrease in adrenal androgens was not related to an excessive divergence from ideal body weight. There was a highly significantly positive correlation between plasma concentrations of all three adrenal androgens which supports a metabolic interrelationship.

Serum levels of testosterone precursors, testosterone and estradiol in 10 animal species.

Blood levels of testosterone precursors, i.e. pregnenolone, progesterone, 17 alpha-hydroxyprogesterone, androstendione, DHEA, and delta 5-androstendiol as well as testosterone and estradiol are measured in 10 animals each of 10 different species. The determination is done by radioimmunoassay with steroidspecific antibodies. Precursors of the delta 5-pathway (DHEA, androstendiol) are low in the red deer, dog, cat, rat and guinea pig. Precursors of the delta 4-pathway (progesterone, 17-hydroxprogesterone, androstendione) are lower in the bull, boar, ram, stallion and rabbit thus indicating a predominance of different pathways in the animal species studied herein. Pregnenolone concentrations are of equal height in all animals, testosterone is lowest in the cat and stallion. In the latter species the estradiol/testosterone ratio is spectacular high.

Gynecomastia in association with a complex tumor of the testis secreting chorionic gonadotropin: studies on the testicular venous effluent.

The levels of progesterone, 17 alpha-hydroxyprogesterone, androstenedione, testosterone and estradiol were measured in the testicular venous effluent from a testis containing a complex malignant tumor associated with gynecomastia and increased serum levels of beta-human chorionic gonadotropin. An abnormally low testosterone/estradiol ratio was encountered (83 in the peripheral serum and 101 in the spermatic venous effluent). On the basis of the available data no delineation could be made as to the relative contributions to estradiol production of tumor tissue and Leydig cells.

Androgen binding capacity and 5 alpha-reductase activity in pubic skin fibroblasts from hirsute patients.

We have measured the total (cytosolic plus nuclear) androgen binding capacity of pubic skin fibroblasts from nine patients with hirsutism of various origin. Confluent intact cell monolayers were incubated with increasing concentrations (0.05-2 nM) of [3H]dihydrotestosterone ([3H]DHT) with or without a 200-fold excess of unlabeled DHT. The androgen binding capacities (mean +/- SD) were similar in normal men (411 +/- 171 fmol/mg DNA), women (310 +/- 103 fmol/mg DNA), and hirsute patients (313 +/- 141 fmol/mg DNA) regardless of the plasma androgen levels. In contrast, the 5 alpha-reductase level in pubic skin fibroblasts (mean +/- SD) was, as previously described, higher in hirsute women (3.3 +/- 2.6 fmol/micrograms DNA . h) than in normal women (1.1 +/- 0.6 fmol/microgram DNA . h; P less than 0.05). We conclude from these data that: 1) increased androgen binding capacity cannot be held responsible for hypersensitivity to androgens in hirsutism; 2) the androgen receptor is not regulated by androgens in human skin, as similar levels are observed in men, women, and hirsute patients; 3) this contrasts with 5 alpha-reductase activity and emphasizes the importance of this enzyme as an amplifier of androgen action in areas where it is stimulated by androgens, such as pubic skin.