Metabolism of testosterone and androstenedione in normal and ovariectomized women

Ovary removal modifies liver message RNA profiles in single Comb White Leghorn chickens

Ovaries produce sex hormones, and ovariectomized animals are often used as models for ovarian dysfunction. The liver is a vital organ involved in metabolism and immunity. In the present study, we conducted experiments to investigate the effects of ovariectomy on transcription and metabolic processes in the liver in chicken. Eight Single Comb White Leghorn (SCWL) female chickens were ovariectomized at 17 wk of age, and 8 intact SCWL females served as controls. At 100 wk of age, all chickens were euthanized. High-throughput transcriptome sequencing was performed on liver RNA obtained from ovariectomized and intact females. A total of 267 differentially expressed genes (DEG) were identified in our study. After analysis using DAVID functional annotation tool, one significant Kyoto Encyclopedia of Genes and Genomes pathway, the phosphatidylinositol signaling pathway, was clustered. Gene Ontology enrichment analysis yielded 46 significant Gene Ontology terms. Among terms describing biological processes, the glycerolipid metabolic and lipid localization processes were dominant. The anabolic genes, PEPCK and GK5, and the catabolic genes, VTG1; VTG2; PLD5; DGKQ; DGKE; and FABP3, were detected in ovariectomized chickens. Differentially expressed genes such as ENSGALG00000000162, IL-1Β, SVOPL, and CA12 implied that livers in ovariectomized chickens were subjected to strong inflammatory reactions, whereas defenses against endogenous materials were compromised. A comprehensive view of gene expression in the liver of ovariectomized chickens would advance our understanding of lipid metabolism, glycometabolism, and their relationships to pathologies induced by absence of the ovary. The identified DEG indicated that ovariectomy disturbed lipid metabolism in the liver and was accompanied by an increase in hepatic gluconeogenesis and reductions in phosphatidic acid synthesis and lipid carrier capacity.

Synthesis and biological evaluation of nandrolone-bodipy conjugates

Here, we report synthesis and biological evaluation of fluorescent nandrolone-3-carboxymethyloxime derivatives conjugated with green-emitting bodipy dye via PEG linkers. All the newly-synthesized compounds were evaluated for their effect on cell proliferation in vitro in MCF-7, LNCaP, PC-3 and HEK 293T model cell lines using WST-1 assay. By means of live-cell fluorescence microscopy, the intracellular localization of nandrolone-bodipy conjugates was revealed in endoplasmic reticulum. Moreover, we performed competitive localization study with nonfluorescent nandrolone, metandrolone, boldenone, trenbolone, and testosterone.

Bone mineral density in young women with primary ovarian insufficiency: results of a three-year randomized controlled trial of physiological transdermal estradiol and testosterone replacement

CONTEXT

Women with primary ovarian insufficiency have significantly lower serum estradiol and T levels compared with regularly menstruating women. They also have significantly reduced bone mineral density (BMD).

OBJECTIVE

The objective of the study was to evaluate the efficacy of hormone replacement in maintaining BMD in these young women.

DESIGN AND SETTING

This was a randomized, double-blind, single-center, placebo-controlled clinical trial at the National Institutes of Health clinical center (Bethesda, Maryland).

PARTICIPANTS

Young women with primary ovarian insufficiency participated in the study.

INTERVENTIONS

We compared the effect of estradiol and progestin replacement (n = 72) vs estradiol, progestin, and T replacement (n = 73) on BMD. We also compared findings with a contemporaneous control group of normal women (n = 70). All patients received transdermal estradiol (100 μg/d) plus oral medroxyprogesterone acetate 10 mg/d (12 d/mo) for a 3-month run-in period before being randomized in a double-blinded fashion to the addition of transdermal T (150 μg/d) or placebo.

MAIN OUTCOME MEASURE

Change in BMD at the femoral neck was measured by dual-energy x-ray absorptiometry.

RESULTS

At screening, patients had significantly lower femoral neck BMD compared with control women (0.77 vs 0.81 g/cm(2), P = .001) and did not differ in body mass index, age at menarche, or education level. Normal control women lost femoral neck BMD over the study period, whereas patients on estradiol and progestin therapy gained BMD; and at the end of the study period, femoral neck BMD of patients on estradiol and progestin therapy did not differ from that of control women (0.80 g/cm(2) in both groups, P = .9). The addition of T showed no further benefit (percentage change in BMD 3.9 vs 2.4, respectively, P = .9). Nonetheless, using a repeated-measures model, the T group achieved a mean BMD in the femoral neck 0.015 g/cm(2) higher than the placebo group at 3 years (95% confidence interval -0.005 to 0.034, P = .13). Similar findings were observed in the lumbar spine BMD as well.

CONCLUSION

Long-term physiological transdermal estradiol replacement in combination with oral medroxyprogesterone acetate restores mean femoral neck BMD to normal in young women with spontaneous 46,XX primary ovarian insufficiency. However, the addition of physiological transdermal T replacement did not provide additional benefit.

Differential effect of amphetamine on c-fos expression in female aromatase knockout (ArKO) mice compared to wildtype controls

Estrogen may be involved in psychosis by an interaction with central dopaminergic activity. Aromatase knockout mice are unable to produce estrogen and have been shown to display altered behavioural responses and effects of the dopamine releaser, amphetamine. This study investigates the effect of gonadal status on amphetamine-induced c-fos expression in the brains of female aromatase knockout and wildtype mice. Six groups of mice were treated intraperitoneally with saline or 5mg/kg amphetamine. Fos immunoreactivity was assessed in the cingulate cortex, caudate putamen and nucleus accumbens. Aromatase knockout mice showed markedly reduced amphetamine-induced Fos immunoreactivity compared to wildtype mice. However, the amphetamine response was restored in aromatase-knockout mice after ovariectomy, which reduced this effect in wildtype controls. Estrogen supplementation reversed the effect of ovariectomy in wildtype mice but had no additional significant effect in aromatase-knockout mice. These results indicate that mechanisms involved in amphetamine-induced c-fos expression are altered in aromatase knockout mice and that the primary hormone involved in this effect is not estrogen, but may be another factor released from the ovaries, such as an androgen. These results provide new insight into the effect of gonadal hormones on amphetamine induced c-fos expression in this mouse model of estrogen deficiency. These results could be important for our understanding of the role of sex steroid hormones in psychosis.

Ovarian androgen production in postmenopausal women

CONTEXT

Several studies previously reported that the postmenopausal ovary produces androgens. However, these findings have recently been questioned in a group of women with adrenal insufficiency.

OBJECTIVE

We sought to use contemporary assay methodologies to investigate whether the postmenopausal ovary is hormonally active and contributes to the circulating pool of androgens.

DESIGN AND PATIENTS

Serum was collected from the ovarian veins of 13 postmenopausal women undergoing total abdominal hysterectomy and bilateral oophorectomy, with sufficient quantities obtained to allow for measurement of several hormones. Serum was also analyzed from peripheral blood collected preoperatively, intraoperatively, and postoperatively.

SETTING

The study took place at the Los Angeles County Women's and Children's Hospital, University of Southern California Keck School of Medicine.

MAIN OUTCOME MEASURES

Testosterone (T), androstenedione (A), dehydroepiandrosterone (DHEA), estrone (E1), and estradiol (E2) were measured by RIA with preceding organic solvent extraction and Celite column chromatography.

RESULTS

Statistically significant gradients were seen between the ovarian venous and peripheral samples for T, A, DHEA, E1, and E2. Postoperative levels of T and E1, but not A, DHEA, or E2, were statistically significantly lower than preoperative levels. A gradient for T between the ovarian venous and peripheral blood was present in four of five women who were menopausal for more than 10 yr.

CONCLUSIONS

The postmenopausal ovary is hormonally active, contributing significantly to the circulating pool of T. Furthermore, this contribution appears to persist in women as long as 10 yr beyond the menopause.

Transdermal testosterone for women: a new physiological approach for androgen therapy

Transdermal testosterone patches and topically applied gels have become well accepted for the treatment of testosterone deficiency in men and are currently being developed in appropriate dosage strengths for androgen therapy in women. The furthest developed among these products is an investigational testosterone matrix patch which is now in phase III clinical trials for the treatment of sexual dysfunction in oophorectomized and naturally menopausal women. This review article discusses the biopharmaceutical rationale for the transdermal delivery of testosterone to women, illustrates and quantitatively analyzes the pharmacokinetics and metabolism of the testosterone matrix patch and a recently investigated testosterone gel, and summarizes the efficacy and safety data that have been reported in phase II studies of the testosterone matrix patch in surgically menopausal women with sexual dysfunction and HIV-infected women with the AIDS wasting syndrome. The different effects of oral and transdermal estrogen therapy (ET) on the concentrations of total and free testosterone attained with the testosterone matrix patch are contrasted. Although still in development, transdermal testosterone therapy appears to be a promising new approach for providing physiologically based androgen therapy to women.

The enantioselective immunoaffinity extraction of an optically active ibuprofen-modified peptide fragment

Acyl glucuronides are known to produce the covalently bound protein adducts which may be the cause of hypersensitivity and toxic responses to acidic drugs. The structural analysis of the drug-protein adducts is therefore needed. From this point of view, we developed an enantioselective immunoaffinity extraction method, which employs an immobilized antibody to specifically isolate peptide fragments that have been modified with optically active ibuprofen. Rabbits were immunized with (S)-ibuprofen coupled to bovine serum albumin through a beta-alanine group. The elicited antibody strongly recognizes the asymmetric center and the isobutylphenyl moiety of (S)-ibuprofen and its conjugates but has a low affinity for their anti podes. A 0.5-mL aliquot of the immunosorbent (11.5 mg of IgG/mL gel) prepared by immobilization of the antibody was capable of retaining up to 1 microg of (S)-ibuprofen. When a mixture of substance P with (R)- and (S)-ibuprofen-modified substance P was loaded on the immunosorbent, the (S)-ibuprofen-modified substance P was selectively retained. The modified peptide was quantitatively recovered by elution with 10 mM ammonium acetate buffer (pH 5.0)/methanol (5:95, v/v). The proposed method would be useful for the structural characterization of optically active ibuprofen-modified human serum albumin.

Dynamics of the development of multiple follicles during ovarian stimulation for in vitro fertilization using recombinant follicle-stimulating hormone (Puregon) and various doses of the gonadotropin-releasing hormone antagonist ganirelix (Orgalutran/Antagon)

OBJECTIVE

To investigate relations between dose of GnRH antagonist and follicular phase characteristics.

DESIGN

Randomized controlled multicenter trial.

SETTING

Tertiary referral fertility centers.

PATIENT(S)

Three hundred and twenty-nine IVF patients.

INTERVENTION(S)

Ovarian stimulation for IVF with recombinant FSH starting on cycle day 2. From cycle day 7 onwards, cotreatment was provided with 0.0625, 0.125, 0.25, 0.5, 1.0, or 2.0 mg/d GnRH antagonist.

MAIN OUTCOME MEASURE(S)

Number of follicles, total follicular surface area, gonadotropin, and serum steroid concentrations.

RESULT(S)

In 311 patients, similar follicular growth was observed in all treatment groups. FSH levels increased during the follicular phase. Late follicular phase LH, androstenedione (AD), and E(2) levels showed a GnRH antagonist dose-related decrease (P<0.05). Late follicular phase E(2) levels correlated with total follicular surface area, AD, LH, and FSH (all P<0.001). Increasing GnRH antagonist doses exhibited additional suppressive action on E(2) levels.

CONCLUSION(S)

Follicular growth was unaffected by the dose of GnRH antagonist. A rise in follicular phase FSH serum concentrations during the follicular phase, largely related to exogenous FSH, enabled ongoing follicular growth in all treatment groups. The effect of GnRH antagonist on late follicular phase E(2) levels could not be exclusively attributed to suppression of LH.

The climacteric ovary as a functional gonadotropin-driven androgen-producing gland

OBJECTIVE

To assess the hypothesis that the climacteric ovary is a functional endocrine gland.

DESIGN

Review of the English-speaking literature as it relates to the physiology and pathophysiology of the climacteric ovary.

RESULTS

By several accounts, the climacteric ovary appears to be a gonadotropin-dependent androgen-producing gland. Although the estrogen-producing potential of the climacteric ovary remains a matter of controversy, most studies would suggest limited aromatase activity.

CONCLUSIONS

[1] The climacteric ovary is not a defunct endocrine organ. [2] The climacteric ovary is a site of gonadotropin reception and action. [3] The climacteric ovary contributes few if any estrogens to the circulating pool by way of direct production. [4] Circulating estrogens are derived virtually exclusively from the extraglandular conversion of androgens, a proportion of which are of ovarian origin. [5] The climacteric ovary contributes 40% and 20% of the total production rates of T and androstenedione, respectively. [6] Androgen biosynthesis by the climacteric ovary is partially gonadotropin-dependent.

Effects of moderate consumption of alcoholic beverages on endocrine function in postmenopausal women. Bases for hypotheses

That alcoholic beverage consumption has not yet received attention as a variable that might influence the estrogenization of postmenopausal women is discussed within the context of the growing proportion of postmenopausal women in the population, their disease risk vis-à-vis estrogenization, and survey findings that report that the majority of postmenopausal women use alcoholic beverages to at least some degree. The available literature is reviewed concerning the effects of acute or chronic ethanol administration, alcoholic beverage consumption, or the administration of phytoestrogen-containing congeners of bourbon on the endocrine status of postmenopausal women or relevant animal models. The basic components of postmenopausal endocrine function and the factors known to affect endocrine status are presented. The importance of incorporating known endocrine-modulating factors into the design of future studies so as to maximize the detection of alcohol effects in postmenopausal women is emphasized.

Deuterium labelled steroid hormones: tracers for the measurement of androgen plasma clearance rates in women

A method employing stable isotope-labelled tracers and gas chromatograph-mass spectrometry (GC-MS) analysis has been used to measure the plasma clearance rates (PCR's) of androstenedione (A) and testosterone (T) in normal women and women with androgen abnormalities including hirsutism and polycystic ovary syndrome. A solution of deuterium-labelled A and T is infused at a constant rate and blood samples taken at 2 and 2.25 h. Solvent extracts of the derived plasma samples, to which an internal standard has been added, are derivatized with pentafluoropropionic anhydride and the endogenous steroid and deuterated steroid are quantitated after an injection of the derivatization mixture into a capillary column GC-MS. The concentration of the deuterated steroid in the infusion mixture is measured and the PCR is calculated. In premenopausal normal women the PCRA is 1950 +/- 184 1/24 h (n = 5) and the PCRT is 484 +/- 82 1/24 h (n = 7).

Androstenedione, 17 beta-estradiol and progesterone plasma levels in gonadotropins induction of ovulation

A comparison of peripheral patterns of androstenedione (A), 17 beta-estradiol (E2) and progesterone (P) is reported in ten infertile women during HMG-HCG induction of ovulation, in order to assess the site of ovarian secretion of plasma A and the possible influence on conception. Evidence for both the follicular and luteal secretion of plasma A is suggested, in addition to the stromal and adrenal contributions, since a highly significant (p less than 0.001) correlation between A and E2 plasma levels was shown during the treatment. In three cycles of conception, plasma A showed a periovulatory peak and drop, followed by a luteal increase, all of which are characteristic of E2.

Metabolic clearance rates of androgens and oestrogens in ageing women

Using the constant infusion technique we have measured the metabolic clearance rates (MCR) for delta 4-androstenedione (A), testosterone (T), oestrone (E1) and oestradiol (E2) in a large group of post-menopausal women. Their mean +/- SE age was 64.5 +/- 1.6 yr, their ages ranged from 46-90 yr. When the MCRs for each steroid were related to age by linear regression analysis no significant correlation was found for any of the steroids. Similarly, when the women were grouped according to their age by decade, the mean MCR for each steroid showed no trend with increasing age. There was no difference in the MCRs for A, T and E1 of the post-menopausal women and a large group of pre-menopausal women. However, there was a significant decrease in the mean MCR for E2 between the two groups which is probably related to the marked decrease in circulating E2 in post-menopausal women. We conclude that for these steroids age, per se, does not appear to be a major determinant of the MCR.

Effect of age on plasma androstenedione concentration in oophorectomized women

Plasma androstenedione concentration was measured in 92 oophorectomized women in the age range 33 to 76 years. Although this concentration was significantly inversely correlated with age, the data suggest a discrete change in the first half of the sixth decade rather than a continuous fall.

Serum concentrations of estrone, androstenedione, testosterone and sex-hormone-binding globulin in postmenopausal women with breast cancer and in age-matched controls

The concentrations of estrone (E1), androstenedione (A), testosterone (T) and sex-hormone-binding globulin (SHBG) in the serum were determined in 122 postmenopausal women, unselected with respect to age and stage of disease and with a newly diagnosed breast cancer. The results were compared with those in 122 age-matched women without breast cancer, selected from the population register. The patients were found to have a significantly higher mean level than the controls of E1 (132 and 108 pmol/l), A (2.5 and 1.6 nmol/l) and T (1.54 and 1.38 nmol/l) and a lower level of SHBG (40.2 and 47.3 nmol/l) in the serum. A multiple regression analysis revealed in the control group that the serum level of E1 was significantly correlated to A (r = 0.48, p less than 0.001) and T (r = 0.45, p less than 0.001). In the patient group E1 was only slightly correlated to T (r = 0.25, p less than 0.01) and not to A (r = 0.10, p greater than 0.05). A significant negative correlation was found between SHBG and weight in both groups. Otherwise no significant correlations were found between any of the hormone levels and age, stage of disease of weight. It was concluded that an increased availability of A and T, leading to an increased androgenic stimulation--and therefore decreased SHBG--and an increased E1 level, is the most reasonable explanation for the findings. The lack of correlation between E1 and A in the patient group is however difficult to explain and the results do not seem to fit into a definite hypothesis.

The relation between plasma androstenedione and oestrone levels in untreated and corticosteroid-treated post-menopausal women

Plasma oestrone (E1) and androstenedione (A) were measured in 96 untreated and 18 corticosteroid-treated post-menopausal women. Levels of both hormones were consistently lower in the steroid-treated cases, presumably due to suppression of ACTH secretion. There was a clear relationship between A and E1 levels in both groups and when the data were pooled they formed a continuous series with a curvilinear relationship going through the origin. This relationship could be described by an equation based on Michaelis-Menten kinetics, suggesting that the rate of A to E1 conversion is an inverse function of the plasma androstenedione level. The main determinant of plasma E1 was plasma A; body weight and age were of subsidiary importance. Secondary oestrogen deficiency may be a factor in the genesis of steroid-induced osteoporosis in post-menopausal women and oestrogen therapy may be indicated in this group of patients.

The in vivo metabolism of androgens by muscle and adipose tissue of normal men

Androstenedione and testosterone labeled with 3H and 14C were fused simultaneously at constant rates into the brachial arm vein of 10 normal men. During the infusions blood samples were obtained from the brachial artery, a deep vein draining primarily muscle and a superficial vein draining primarily adipose tissue of the arm contra-lateral to the infusion. In the 10 men the mean +/- SE value for the fractional metabolism of adrostenedione by muscle is 0.20 +/- 0.30 which is not different from the mean value for the fractional metabolism by androstenedione by adipose tissue, 0.29 +/- 0.04. The mean value for the metabolism of testosterone by muscle, 0.04 +/- *.01, is significantly less than the metabolism by adipose tissue, *.11 +/- 0.01. Interconversion between adrostenedione and testosterone occurs in both tissues. The mean value for pA,T A,M is 0.024 + 0.005 and for pA,T A,AT is 0.024 +/- 0.005. The mean value for pT,A A,M is 0.005 +/- 0.003 and for pT,A A,AT is 0.008 +/- 0.003. The fractional metabolism of these androgens by these tissues is similar to the fractional metabolism of estrone and estradiol by these same tissues. Muscle appears to contribute about 5-12% of the overall metabolism of androstenedione and testosterone and 10-15% to theoverall conversion of androstenedione to testosterone. Adipose tissue contributes about 2-7% of the overall metabolism of these androgens and 5-10% of the overall conversion of androstenedione to testosterone, but less than 2% to the overall conversion of testosterone to androstenedione. In normal men, muscle appears to be more important to the metabolism of androstenedione and testosterone than is adipose tissue.

Polycystic ovarian disease

Sex hormone binding globulin (SHBG) capacity was reduced in 9 of 31 patients with polycystic ovarian (PCO) disease and the mean level in PCO patients was significantly less (p less than 0.001) than normal. Serum testosterone levels were elevated in 21 of 32 PCO patients and the mean level was significantly elevated (p less than 0.001). Serum androstenedione values were raised in 17 of 31 patients and the mean value was also significantly raised (p less than 0.001). Serum dehydroepiandrosterone sulphate (DHAS) concentrations were elevated in only 2 of 14 patients. Urinary 17-oxo and 17-oxogenic steroids were normal in all patients studied. Basal follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were normal but LH release following injection of luteinizing hormone-releasing hormone (LH-RH) was enhanced. A highly significant negative correlation (r=--0.449; p less than 0.01) was found between the logarithm of testosterone and the logarithm of LH levels. Serum prolactin concentrations were elevated in 4 of 21 PCO patients. Thyroid-stimulating hormone (TSH) values were normal. Eighteen of 20 patients ovulated following treatment with clomiphene and nine became pregnant. Five of 12 of patients treated with oestrogen/progesterone preparations noticed an improvement in their hirsutism. It is suggested that the normal cyclical release of LH is inhibited in PCO disease by a negative feedback by androgens to the hypothalamus or the pituitary, and that wedge resection should be reserved for patients in whom other forms of treatment have failed.

Plasma androgen levels during the menstrual cycle

Utilizing RIA methods, T, DHT, delta 4, and DHEA levels were determined daily during a complete cycle in 15 normal young women with apparently normal ovulatory cycles. T, DHT, and delta 4 levels showed statistically significant cyclical variations, with highest values in the periovulatory period and lowest values in early follicular and late luteal phase. DHEA levels showed random variations during the cycle. The failure to detect these variations by some authors may be related to the relatively large interindividual variation in plasma levels.