Plasma Estrone Research Articles

Hepatic Gene Expression and Metabolite Profiles of Androstenone and Skatole Relative to Plasma Estrone Sulfate Levels in Boars.

Testicular steroids can alter the activity and expression of enzymes within the liver and may influence the metabolism of skatole and androstenone, which are responsible for boar taint. Plasma levels of estrone sulfate (E1S) are indicative of the steroidogenic capacity of the boar and are variable between animals of similar live weights at slaughter. This study aimed to characterize the relationship between steroidogenic capacity and the metabolism of boar taint compounds by relating plasma E1S levels at slaughter weight to the expression levels of genes regulating the metabolism of androstenone and skatole, along with their respective metabolite profiles. RT-qPCR was used to evaluate gene expression in the liver. Hepatocytes were also isolated and treated with androstenone or skatole, with metabolite levels in the incubation media quantified by high-performance liquid chromatography. Plasma E1S levels ranged from 2.2-108.5 ng/mL and were positively correlated with overall skatole metabolism (p = 0.038), the production of metabolites 3-methyloxindole (p = 0.026) and 3-hydroxy-3-methyloxindole (p = 0.036), and expression levels of key genes involved in skatole metabolism, specifically CYP2C33 (p = 0.0042), CYP2C49 (p = 0.022), and CYB5R1 (p = 0.017). There was no association between androstenone metabolism and plasma E1S concentrations; however, there was evidence of possible co-regulation amongst genes involved in the metabolism of androstenone, skatole, and estrogens. These findings indicate that steroidogenic capacity is related to the rate of skatole, but not androstenone metabolism, in slaughter-weight boars.

The impact of vegetarian diet on sperm quality, sex hormone levels and fertility: a systematic review and meta-analysis.

An increasing number of people have adhered to a vegetarian diet for several years. Nowadays, the favourable effect of this dietary pattern on metabolic diseases is well established, but its impact on fertility and reproductive health as a serious health concern is not clear yet. Therefore, we aim to summarise existing evidence regarding the possible association between a vegetarian diet and fertility as measured by key indicators such as sperm quality and sex hormone levels. We systematically searched online databases, including PubMed, ISI, Scopus and Google Scholar, up to 1 December 2022 using relevant keywords. We included observational studies that compared semen quality, sex hormone levels and infertility in people who adhered to a vegetarian diet versus an omnivore diet. Heterogeneity between studies was assessed using I2 and Q tests. Standardised mean differences (SMD) using a random/fixed model were calculated to assess outcomes between vegetarians and omnivores in included articles. Finally, out of 972 documents that were retrieved, 20 articles met our inclusion criteria, and 16 were eligible for quantitative synthesis. Results of meta-analyses showed that there were no significant differences between vegetarians and omnivores in terms of semen quality parameters, including total sperm count, total and progressive sperm motility, sperm morphology and sperm concentration. Seven studies on female sex hormone profiles were eligible for meta-analysis. The only significant difference was the lower level of plasma oestrone in vegetarians (pooled SMD: -0.56; 95% confidence interval [CI]: -1.08, -0.05; p-value = 0.03) compared to omnivores. Furthermore, our meta-analysis revealed significantly higher sex-hormone-binding globulin levels in vegetarian men than in omnivores (pooled SMD: 0.52; 95% CI: 0.18, 0.86; p-value = 0.002). Despite the numerous health benefits of a vegetarian diet, our review suggested that there were no conclusive positive or negative associations between vegetarian diet and semen quality, sex hormone levels and infertility. Further studies are recommended to better understand vegetarian dietary pattern effect on infertility and reproductive health.

281 The Relationship between Postnatal Hormone Concentrations and the Development of Boar Taint at Puberty

Abstract The development of boar taint is dependent on the balance between the rate of androstenone synthesis and metabolism, which regulates the quantity of androstenone available for accumulation in the fat. The pubertal production of androstenone and other sex steroids is influenced by sexual maturity status and preceded by a significant period of hormone production during postnatal development that occurs from 14 to 35 days of age (DOA). However, the relationship between postnatal and pubertal hormone production is not well understood. Therefore, the purpose of this study was to determine if postnatal hormone concentrations can be used to predict sexual maturity status and boar taint development at puberty. Crossbred [(Yorkshire x Landrace) x Duroc] boars (n=90)] were housed in groups of 10. Blood samples were taken at 14, 21, 28, and 35 DOA and again at 120, 130, and 140kg live weights (LWs) along with backfat samples. Plasma and fat androstenone concentrations were quantified using an androstenone-specific ELISA. Plasma estrone sulfate (E1S) concentrations were determined by RIA and used as an indicator of sexual maturity status. Statistical analysis was performed using Spearman correlation. Several nonlinear monotonic relationships were identified between postnatal and pubertal hormone concentrations and are presented in Table 1. A moderate positive correlation was identified between plasma androstenone concentrations at 21 and 28 DOA and fat androstenone concentrations at 120, 130, and 140kg LWs, and between E1S concentrations at 21 DOA and E1S concentrations at 120, 130, 140kg LWs. However, the strength of the relationship between postnatal and pubertal hormone concentrations was insufficient for accurately predicting sexual maturity status or boar taint at puberty. These results suggest that additional factors regulating the development of boar taint, such as the rate of metabolism or accumulation, should be considered in future efforts to develop a predictive model using postnatal hormone concentrations.

Plasma sex hormones and risk of conventional and serrated precursors of colorectal cancer in postmenopausal women

BackgroundSex hormones have been suggested to play a role in colorectal cancer (CRC), but their influence on early initiation of CRC remains unknown.MethodsWe retrospectively examined the associations with risk of CRC precursors, including conventional adenomas and serrated polyps, for plasma estrone, estradiol, free estradiol, testosterone, free testosterone, sex hormone-binding globulin (SHBG), and the ratio of estradiol to testosterone among 5404 postmenopausal women from the Nurses’ Health Study I and II. Multivariable logistic regression was used to calculate the odds ratio (OR) and 95% confidence intervals (CI). Given multiple testing, P < 0.005 was considered statistically significant.ResultsDuring 20 years of follow-up, we documented 535 conventional adenoma cases and 402 serrated polyp cases. Higher concentrations of SHBG were associated with lower risk of conventional adenomas, particularly advanced adenomas (multivariable OR comparing the highest to the lowest quartile, 0.40, 95% CI 0.24–0.67, P for trend < 0.0001). A nominally significant association was found for SHBG with lower risk of large serrated polyps (≥ 10 mm) (OR, 0.47, 95% CI 0.17–1.35, P for trend = 0.02) as well as free estradiol and free testosterone with higher risk of conventional adenomas (OR, 1.54, 95% CI 1.02–2.31, P for trend = 0.03 and OR, 1.33, 95% CI 0.99–1.78, P for trend = 0.03, respectively).ConclusionsThe findings suggest a potential role of sex hormones, particularly SHBG, in early colorectal carcinogenesis.

Simultaneous Measurement of Sex Steroid Hormones in Largemouth Bass (Micropterus salmoides) Plasma by Application of Liquid Chromatography-Tandem Mass Spectrometry.

Sex steroid hormones are potential biomarkers of reproductive function in teleost fish, but their measurement continues to rely on antibody-based assays. The objective of this study was to optimize a robust and simultaneous liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for measurement of eight steroid hormones (cortisol, 11-ketotestosterone, estradiol, 17α-ethynyl estradiol, estrone, estriol, progesterone and testosterone) in fish plasma. The extraction was followed by liquid-liquid extraction with tert-butyl methyl ether and time scheduled multi-reaction monitoring (sMRM) was used for quantitation of steroids. Validation of method performance using charcoal-stripped human plasma showed extraction recoveries for eight steroids ranged from 85.5 to 108.2% with matrix effects>80%. The limits of quantitation were 0.01pg/μL for testosterone, 0.05pg/μL for cortisol and progesterone, 0.1pg/μL for 11-ketotestosterone, estradiol and estrone, 0.125pg/μL for estriol and 0.25pg/μL for 17α-ethynyl estradiol. The proposed method was applied to plasma samples of largemouth bass (Micropterus salmoides) collected from contaminated (Lake Apopka) and reference sites (Wildcate Lake) in Florida. Concentrations of testosterone, cortisol, estradiol and estrone were significantly different in female fish, but plasma concentration of cortisol was only statistically different in male fish between two sites (P<0.05). This study demonstrates the application of a robust LC-MS/MS analysis for a range of sex steroid hormones representative of endocrine function in a top predator, largemouth bass.

Longitudinal changes in plasma sex hormone concentrations correlate with changes in CT-measured regional adiposity among Japanese American men over 10years.

Ageing in male adults is typically accompanied by adiposity accumulation and changes in circulating sex hormone concentrations. We hypothesized that an ageing-associated increase in oestrogens and decrease in androgens would correlate with an increase in adiposity. 10-year prospective, observational study. A total of 190, community-dwelling men in the Japanese American Community Diabetes Study. At 0 and 10years, CT scanning quantified intra-abdominal fat (IAF) and subcutaneous fat (SCF) areas while plasma concentrations of oestradiol, oestrone, testosterone and dihydrotestosterone were measured by liquid chromatography-tandem-mass spectrometry at each time point. Multivariate linear regression analyses assessed correlations between 10-year changes in hormone concentrations and IAF or SCF, adjusting for age and baseline fat depot area. Participants were middle-aged [median 54.8 years, interquartile range (IQR) 39.9-62.8] men and mostly overweight by Asian criterion (median BMI 24.9, IQR 23.3-27.1) and with few exceptions had normal sex-steroid concentrations. Median oestradiol and dihydrotestosterone did not change significantly between 0 and 10years (P=.084 and P=.596, respectively) while median oestrone increased (P<.001) and testosterone decreased (P<.001). Median IAF and SCF increased from 0 to 10years (both P<.001). In multivariate analyses, change in oestrone positively correlated (P=.019) while change in testosterone (P=.003) and dihydrotestosterone (P=.014) negatively correlated with change in IAF. Plasma oestradiol and oestrone positively correlated with change in SCF (P=.041 and P=.030, respectively) while testosterone (P=.031) negatively correlated in multivariate analysis. Among 190 community-dwelling, Japanese American men, increases in IAF were associated with decreases in plasma androgens and increases in plasma oestrone, but not oestradiol, at 10years. Further research is necessary to understand whether changing hormone concentrations are causally related to changes in regional adiposity or whether the reverse is true.

LC-APCI+-MS/MS method for the analysis of ten hormones and two endocannabinoids in plasma and hair from the mice with different gut microbiota

The effect of gut microbiota on the activity of the HPA and HPG axes and ECS is a short-term or long-lasting process remains unclear in rodents. However, the extant studies focused only on its short-term effect on the HPA activity because there is lack of reliable biomarkers characterizing short-term activity of the HPG axis and ECS and long-term activities of the three endocrine systems. The endogenous levels of aldosterone (ALD), 11-dehydrocorticosterone (11-DHC), estradiol (E2), estrone (E1), androstenedione (A4), dihydrotestosterone (DHT), corticosterone (CORT), dehydroepiandrosterone (DHEA), testosterone (T), progesterone (P), N-arachidonoyl ethanoamide (AEA) and 1-arachydonoyl glycerol (1-AG) in hair and plasma are the potential long-term and short-term biomarkers of the three systems. This study aimed to develop the sensitive and selective methods for simultaneous quantitation of the twelve compounds in rodent’s hair and plasma. Then the methods were used to explore the differences in the hair levels of the twelve compounds between the mice in XZ group possibly having gut microbiota with more diversity and SPF group possibly having gut microbiota with less diversity and the inter-group differences in the plasma levels in the response to 1-h restraint stress. The methods were based on high performance liquid chromatography tandem mass spectrometry with atmospheric pressure chemical ionization in positive mode. The methods were adopted for 20 mg hair and 100 μL plasma, respectively. Hair samples were incubated in methanol at 40 ℃ for 24 h, and were performed by solid phase extraction. Plasma samples were implemented by liquid-liquid extraction with ethyl acetate. The methods showed limit of quantification at 0.06–1.3 pg/mg and 0.03-0.6 ng/mL and recovery ranging between 87.7–115.1 % and 86.1–114.6 % for all compounds in rodent’s hair and plasma, and the intra-day and inter-day coefficients of variation less than 15 %, and good freeze/thaw and short-term stability. The present methods also had good reliability as demonstrated by the sex difference in the testosterone levels in hair and plasma. The inter-group comparison revealed that the mice in XZ group showed significantly higher hair levels than those in SPF group for 1-AG and most of hormones except for T and P. The non-stressed female mice in SPF showed significantly higher plasma levels than those in XZ for AEA and most of hormones except for E2, A4, DHT, T and 1-AG, but there were no inter-group differences for the stressed mice except for DHEA and 11-DHC and for the non-stressed male mice. Additionally, the stressed mice showed significantly higher corticosterone level in plasma than controls for male and female mice in XZ and male mice in SPF, but it was not true for female mice in SPF.

Study on the Association of some Single Nucleotide Polymorphisms of CYP19A1 Gene with Breast Cancer in Vietnamese Women

The CYP19A1 gene encodes for aromatase P450, which is a key enzyme in estrogen metabolism, catalyzes the conversation of testosterone to estradiol and androstenedione to estrone. It is generally believed that polymorphisms in genes coding for key enzymes involved in these pathways could effect to the activity of enzymes, which can change the level of endogenous hormones. Therefore genetic polymorphisms in hormone-related genes could increase the breast cancer susceptibility. In this study, 60 blood samples of breast cancer women and 50 control populations were analyzed to identify the genotype frequency at SNP loci rs10046 C&gt;T and rs2236722 Trp39Arg (T&gt;C) on CYP19A1 using PCR-RFLP and PCR-CTPP respectively. The data were analyzed to determine the association between these polymorphism loci and susceptibility to breast cancer. The result showed that, the genotype frequencies at SNP rs10046 in the control as: CC (14%), CT (48%), TT (38%), in case group are CC (18.33%) , CT (58.33%) and TT (23.34%); at SNP rs2236722 in the control group: TT (94%), TC (6%), in case group TT (90%), TC (10%). The OR analyses for the gene carrying the CC and TC genotypes compared with TT genotype at both loci (OR=2.01; 95% CI=0.87–4.67 with rs10046 and OR = 1.74; 95% CI= 0.40 – 7.42 with rs2236722) indicated that these SNP loci in CYP19A1 have no effect on breast cancer susceptibility.&#x0D; Keywords&#x0D; Breast cancer, SNP, rs10046, rs2236722, CYP19A1 gene&#x0D; References&#x0D; 1. Bora M. T., Tülin Ö., Halil I. K., Sennur I., Calay Z., Oğuz Ö., Turgay I. (2010), “CYP17 (T-34C) and CYP19 (Trp39Arg) Polymorphisms and their Cooperative Effects on Breast Cancer Susceptibility”, In vivo, 24, pp.71–74.2. Chen C., Sakoda L. C., Doherty J. A., Loomis M. M., Fish S., Ray R. M. (2008), “Genetic variation in CYP19A1 and risk of breast cancer and brocystic breast conditions among women in Shanghai, China”, Cancer Epidemiology Biomarkers Prevention, 17(12), pp.3457–3466.3. Dunning A. M., Dowsett M., Healey C. S., Tee L., Luben R. N., Folkerd E., Novik K. L., Kelemen L., Ogata S., Pharoah P. D., Easton D. F., Day N. E., Ponder B. A. (2004), “Polymorphisms associated with circulating sex hormone levels in postmenopausal women”, J. Natl. Cancer Inst., 96(12), pp.936–945.4. Farzaneh F., Noghabaei G., Barouti E., Pouresmaili F., Jamshidi J., Fazeli A. (2016), “Analysis of CYP17, CYP19 and CYP1A1 gene polymorphisms in Iranian women with breast cancer”, Asian Pacific Journal of Cancer Prevention, 17, pp.23–26.5. Ghisari M., Eiberg H., Long M. (2014), “Polymorphisms in phase I and phase II genes and breast cancer risk and relations to persistent organic pollutant exposure: A case-control study in Inuit women”, Environmental Health, 13(1), pp.19.6. Henderson B. E., Ross R., Bernstein L. (1988), “Estrogens as a cause of human cancer: The Richard and Hinda Rosenthal Foundation award lecture”, Cancer Research, 48, pp.246–253.7. Hirose K., Matsuo K., Toyama T. (2004), “The CYP19 gene codon 39 Trp/Arg polymorphism increases breast cancer risk in subsets of premenopausal Japanese”, Cancer Epidemiol BiomarkPrev, 13, pp.1407–1411.8. Kristensen V. N., Harada N., Yoshimura N., Haraldsen E., Lonning P. E. (2000), “Genetic variants of CYP19 (aromatase) and breast cancer risk”, Oncogene, 19, pp.1329–1333.9. Lunardi G., Piccioli P., Bruzzi P., Notaro R., Lastraioli S., Serra M. (2013), “Plasma estrone sulfate concentrations and genetic variation at the CYP19A1 locus in postmenopausal women with early breast cancer treated with letrozole”, Breast Cancer Research and Treatment, 137(1), pp.167–174.10. Miyoshi Y., Iwao K., Ikeda N., Egawa C., Noguchi S., (2000), “Breast cancer risk associated with polymorphism in CYP19 in Japanese women”, Int J Cancer, 89, pp.325–328. 11. Pineda B., García-Pérez M.Á., Cano A., Lluch A., Eroles P. (2013), “Associations between Aromatase CYP19 rs10046 Polymorphism and Breast Cancer Risk: From a Case–Control to a Meta–Analysis of 20.098 Subjects”, PLos One, 8(1), pp.1–9.12. Ralph D. A., Zhao L. P., Aston C. E., Manjeshwar S., Pugh T. W. (2007), “Age-specific association of steroid hormone pathway gene polymorphisms with breast cancer risk”, Cancer, 109, pp.1940–1948.13. Samson M., Rama R., Swaminathan R., Sridevi V., Nancy K. N., Rajkumar T., (2009), “CYP17 (T-34C), CYP19 (Trp39Arg), and FGFR2 (C-906T) polymorphisms and the risk of breast cancer in South Indian women”, Asian Pacific J Cancer Prev, 10, pp.111–116.14. Yang L., Wang X. Y., Li Y. T., Wang H. L., Wu T., Wang B. (2015), “CYP19 gene polymorphisms and the susceptibility to breast cancer in Xinjiang Uigur women”, Genetics and Molecular Research, 14(3), pp.8473–8482.15. Yoshimoto N., Nishiyama T., Toyama T., Takahashi S., Shiraki N., Sugiura H., (2011), “Genetic and environmental predictors, endogenous hormones and growth factors, and risk of estrogen receptor positive breast cancer in Japanese women”, Cancer Science, 102(11), pp.2065–2072.16. Zins K., Mogg M., Schneeberger C., Abraham D., (2014), “Analysis of the rs10046 polymorphism of aromatase (CYP19) in premenopausal onset of human breast cancer”, International Journal of Molecular Sciences, 15(1), pp.712–724.

SLCO1B1 polymorphisms and plasma estrone conjugates in postmenopausal women with ER+breast cancer: genome-wide association studies of the estrone pathway.

Estrone (E1), the major circulating estrogen in postmenopausal women, promotes estrogen-receptor positive (ER+) breast tumor growth and proliferation. Two major reactions contribute to E1 plasma concentrations, aromatase (CYP19A1) catalyzed E1 synthesis from androstenedione and steroid sulfatase (STS) catalyzed hydrolysis of estrone conjugates (E1Cs). E1Cs have been associated with breast cancer risk and may contribute to tumor progression since STS is expressed in breast cancer where its activity exceeds that of aromatase. We performed genome-wide association studies (GWAS) to identify SNPs associated with variation in plasma concentrations of E1Cs, E1, and androstenedione in 774 postmenopausal women with resected early-stage ER+breast cancer. Hormone concentrations were measured prior to aromatase inhibitor therapy. Multiple SNPs in SLCO1B1, a gene encoding a hepatic influx transporter, displayed genome-wide significant associations with E1C plasma concentrations and with the E1C/E1 ratio. The top SNP for E1C concentrations, rs4149056 (p=3.74E-11), was a missense variant that results in reduced transporter activity. Patients homozygous for the variant allele had significantly higher average E1C plasma concentrations than did other patients. Furthermore, three other SLCO1B1 SNPs, not in LD with rs4149056, were associated with both E1C concentrations and the E1C/E1 ratio and were cis-eQTLs for SLCO1B3. GWAS signals of suggestive significance were also observed for E1, androstenedione, and the E1/androstenedione ratio. These results suggest a mechanism for genetic variation in E1C plasma concentrations as well as possible SNP biomarkers to identify ER+breast cancer patients for whom STS inhibitors might be of clinical value.

Estrone and Estradiol Levels in Breast Cancer Patients Using Anastrozole Are Not Related to Body Mass Index.

Objective Obesity is associated with an increased risk for breast cancer. Recent studies have shown that aromatase inhibitors may be less effective in women with a high body mass index (BMI). The aim of this study was to establish the relationship between the BMI and plasma estrone and estradiol levels in postmenopausal women with hormone receptor-positive breast cancer using anastrozole. Methods In this cohort study, the patients were divided into three groups according to BMI (normal weight, overweight and obese) to compare and correlate plasma hormone levels before starting anastrozole hormone therapy and three months after treatment. Plasma hormone levels were compared for age and use of chemotherapy. Results A statistically significant reduction in estrone and estradiol levels was observed between baseline and three months after starting the anastrozole treatment (p < 0.05). There was no statistically significant difference in plasma estrone and estradiol levels among the BMI groups (p > 0.05), but a significant reduction in plasma estrone levels was observed after three-months' treatment relative to baseline in all groups, as well as a reduction in estradiol in the obese group (p < 0.05). The use of chemotherapy and age > 65 years had no influence on plasma steroid levels. Conclusion Changes in estrone and estradiol levels in the studied groups were not associated with BMI, chemotherapy or age.

Endogenous sex hormones and cognitive function in older women

IntroductionWe examined the association between endogenous sex hormones and both objective and subjective measures of cognitive function. MethodsWe followed 3044 women up to 23 years in a prospective cohort study. We measured plasma levels of estrone, estrone sulfate, estradiol, androstenedione, testosterone, dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DHEA-S) in 1989–1990, conducted neuropsychologic testing in 1999–2008, and inquired about subjective cognition in 2012. ResultsOverall, we observed little relation between plasma levels of hormones and either neuropsychologic test performance or subjective cognition. However, after adjustment for age and education, we observed a borderline significant association of higher levels of plasma estrone with higher scores for both overall cognition (P trend = .10) and verbal memory (P trend = .08). DiscussionThere were no clear associations of endogenous hormone levels at midlife and cognition in later life, although a suggested finding of higher levels of plasma estrone associated with better cognitive function merits further research.

Estrogens Correlate with PELP1 Expression in ER Positive Breast Cancer.

The Proline-, glutamic acid- and leucine-rich protein 1 (PELP1) is an estrogen receptor (ER) coactivator and a proto-oncogene known to be deregulated in endocrine cancers. In breast cancer, PELP1 overexpression has been associated with endocrine therapy resistance. Although PELP1 is known to be regulated by estrogens in vitro, its association with estrogen levels within the tissue of breast cancer patients has not previously been assessed. Here, we determined PELP1 mRNA expression levels in paired samples of normal and malignant breast tissue obtained from 32 postmenopausal and 11 premenopausal women. In the total sample set, PELP1 levels were higher in tumors compared to normal breast tissue (P = 0.041). Among postmenopausal women, PELP1 tumor levels correlated positively with estrone (E1) and estradiol (E2) levels in both normal tissue (r = 0.543, P = 0.003 and r = 0.601, P = 0.001, respectively) and plasma (r = 0.392, P = 0.053 and r = 0.403, P = 0.046, respectively). Analyzing all ER+ tumors (n = 26), PELP1 correlated positively with E1 and E2 in tumor tissue (r = 0.562, P = 0.003 and r = 0.411, P = 0.037, respectively) and normal tissue (r = 0.461, P = 0.018 and r = 0.427, P = 0.030, respectively) in addition to plasma E1, E2 and estrone sulphate (E1S) concentrations (r = 0.576, P = 0.003, r = 0.456, P = 0.025 and r = 0.406, P = 0.049, respectively). Finally, PELP1 correlated positively with ER mRNA (ESR1) (r = 0.553, P = 0.026) in ER+ tumors, whereas a negative association between PELP1 and ESR1 (r = -0.733, P = 0.010) was observed in ER- breast tumors. Taken together, tumor PELP1 mRNA expression is associated with estrogen levels in breast cancer, suggesting a potentially important role of PELP1 in ER+ breast cancer growth in vivo.

Development and validation of LC–MS/MS method for quantification of bisphenol A and estrogens in human plasma and seminal fluid

Bisphenol A (BPA) is a widely known endocrine disruptor with estrogenic, antiestrogenic or antiandrogenic properties. BPA could interfere with estrogen metabolism as well with receptor-mediated estrogen actions. Both environmental BPA and estrogens may be traced in body fluids, of which, besides the blood plasma, the seminal fluid is of particular interest regarding their possible interactions in the testis. The method for simultaneously determining BPA and estrogens is then needed, taking into account that their concentrations in these body fluid may differ. Here the method was developed and validated for measurements of BPA, estrone (E1), estradiol (E2) and estriol (E3) in blood plasma and seminal plasma using liquid chromatography–tandem mass spectrometry. Due to the phenolic moiety of all compounds, dansyl chloride derivatization could be used. The analytical criteria of the method with respect to expected concentration of the analytes were satisfactory. The lower limits of quantifications (LLOQ) amounted to 43.5, 4.0, 12.7, 6.7pg/mL for plasma BPA, E1, E2 and E3, and 28.9, 4.9, 4.5, 3.4pg/mL for seminal BPA, E1, E2 and E3, respectively. The concentrations of individual steroids differed between body fluids. To the best of our knowledge, this is the first method that enabled the measurement of estrogens and BPA together in one run. The concentrations of E1, E2 and for the first time also of E3 in seminal plasma in normospermic men are reported.

Ovarian follicular activity during late gestation and postpartum in guanaco (Lama guanicoe).

This study evaluated ovarian activity in late gestation and post-partum in guanacos in captivity. Follicular dynamics was monitored every second day from 40 days before and other 40 after delivery by transrectal sonography and by plasma steroids concentrations. Seven out of eight (87.5%) of gestating females presented ovarian follicular activity under progesterone levels >3 nmol/l with maximum follicular size of 8.42 ± 0.83 mm from days 23 to 1 before delivery. After delivery, all females have follicular wave development from day 0 to 38, with larger follicular size and longer follicular wave phases and interwave interval when compared with pre-partum data. During post-partum period, there was a close relationship between follicle size and estradiol-17β concentration, with r = 0.69 at the beginning of growth phase and r = 0.86 in association with the largest dominant follicle. Plasma estradiol-17β concentration varied from 11.92 to 198.55 pmol/l. Plasma estrone sulfate, free estrone and progesterone returned to baseline concentrations during peripartal period and remained basal thereafter. The results described follicular activity during late gestation and early post-partum period. These findings provide relevant information to understand physiological changes occurring during this reproductive key period in seasonal breeders with long gestation duration as New and Old World camelids.

Hormone and Metabolite Profiles in Nesting Green and Flatback Turtles: Turtle Species with Different Life Histories

Herbivorous turtle, Chelonia mydas, inhabiting the south China Sea and breeding in Peninsular Malaysia, and Natator depressus, a carnivorous turtle inhabiting the Great Barrier Reef and breeding at Curtis Island in Queensland, Australia, differ both in diet and life history. Analysis of plasma metabolites levels and six sex steroid hormones during the peak of their nesting season in both species showed hormonal and metabolite variations. When compared with results from other studies progesterone levels were the highest whereas dihydrotestosterone was the plasma steroid hormone present at the lowest concentration in both C. mydas and N. depressus plasma. Interestingly, oestrone was observed at relatively high concentrations in comparison to oestradiol levels recorded in previous studies suggesting that it plays a significant role in nesting turtles. Also, hormonal correlations between the studied species indicate unique physiological interactions during nesting. Pearson correlation analysis showed that in N. depressus the time of oviposition was associated with elevations in both plasma corticosterone and oestrone levels. Therefore, we conclude that corticosterone and oestrone may influence nesting behaviour and physiology in N. depressus. To summarise, these two nesting turtle species can be distinguished based on the hormonal profile of oestrone, progesterone, and testosterone using discriminant analysis.

Plasma estrone sulfate, clinical biochemistry, and milk yield of dairy cows carrying a fetus from a bull or its clone

The aim of this article was to compare plasma estrone sulfate (E1SO4), clinical biochemistry, and milk yield of dairy cows carrying a female fetus from a bull (BULL) or from its clone (CLONE), evaluating also the relationship between the former variables and the birth weight of the newborn. Sixteen recipient dairy Friesian heifers (10 BULL and 7 CLONE) received a female embryo, obtained by in vitro embryo production and sexing by polymerase chain reaction with the semen of the BULL or the CLONE. Blood samples on all cows were obtained before feed distribution in the morning from jugular vein from 4 weeks before to 4 weeks after calving, to be analyzed for metabolic profile. The samples from late gestation were also analyzed for E1SO4 concentration. To separately assess the effect of calf birth weight (CBW), data were categorized as follows: low (<39 kg; BWT-A), mid (39–46 kg; BWT-B), and high (>46 kg; BWT-C). The plasma concentrations of β-hydroxybutyric acid (BHB, P = 0.019), Na (P = 0.002), Cl (P = 0.026), strong cation–anion balance (P = 0.020), total bilirubin (P = 0.054), and α1-globulin (P = 0.044) were higher in prepartum BULL recipients than those in CLONE, whereas BHB (P = 0.021) and Mg (P = 0.090) were higher in postpartum BULL recipients, while no differences were recorded in the remaining postpartum parameters. The CBW class had significant interaction with week of gestation on antepartum plasma estrone sulfate (P = 0.021), whereas CBW per se affected antepartum plasma BHB (P = 0.021), and nonesterified fatty acids (NEFA; P = 0.011) being higher in BWT-C which also had the lower NEFA concentration during postpartum. Milk yield was unaffected by the sire used, both for quantitative and qualitative aspects. Cows carrying heavier fetus (BWT-C) had a different lactation affected by month compared with the other 2 CBW groups. From these results, there were no differences between BULL and CLONE recipients. Estrone sulfate, BHB, and NEFA may be used to predict CBW and provide different nutritional management during gestation.

Relationship of body mass index with aromatisation and plasma and tissue oestrogen levels in postmenopausal breast cancer patients treated with aromatase inhibitors

BackgroundRecent data have raised concern about the clinical efficacy of aromatase inhibitors in overweight and/or obese breast cancer patients. We report in vivo aromatase inhibition and plasma and tissue oestrogen levels in relation to body mass index (BMI) status among breast cancer patients treated with different aromatase inhibitors. MethodsWe compared data on in vivo aromatase inhibition (64 patients) as well as plasma and tissue oestrogen levels from patients participating in our studies to BMI values. ResultsWe found a weak positive correlation between pretreatment aromatisation level and BMI (n=64; R=0.236; p=0.060) but no correlation between on-treatment aromatisation levels or percentage aromatase inhibition and BMI within patient subgroups treated with any of a panel of aromatase inhibitors. Pre-treatment levels of plasma estradiol (p<0.001), estrone (p=0.001) and estrone sulphate (p=0.002) correlated to BMI. While on-treatment levels of plasma estrane sulphate correlated to BMI in patients on letrozole (R=0.601; p=0.001; n=25 for all) or anastrozole (n=12; R=0.611; p=0.035) therapy, letrozole suppressed plasma estrone sulphate more than anastrozole independent of BMI. No correlation between on-treatment tumour oestrogen levels and BMI was recorded. ConclusionsOur unique data do not support a lack of effective aromatase inhibition in overweight patients or therefore a need for alternative therapy. The higher levels of estrogens in overweight postmenopausal breast cancer patients before and during aromatase inhibition may be due to effects of BMI on oestrogen metabolism rather than aromatisation.

Aromatase inhibitors affect vaginal proliferation and steroid hormone receptors

Women with breast cancer who are treated with aromatase inhibitors often experience vaginal atrophy symptoms and sexual dysfunction. This work aims to study proliferation and the presence and distribution of steroid hormone receptors in vaginal biopsies in relation to vaginal atrophy and vaginal pH in women with breast cancer who are on adjuvant endocrine treatment and in healthy postmenopausal women. This is a cross-sectional study that compares postmenopausal aromatase inhibitor-treated women with breast cancer (n = 15) with tamoxifen-treated women with breast cancer (n = 16) and age-matched postmenopausal women without treatment (n = 19) or with vaginal estrogen therapy (n = 16). Immunohistochemistry was used to study proliferation and steroid hormone receptor staining intensity. Data was correlated with estrogen and androgen levels, vaginal atrophy scores, and vaginal pH. Aromatase inhibitor-treated women had a lower grade of proliferation, weaker progesterone receptor staining, and stronger androgen receptor staining, which correlated with plasma estrone levels, vaginal atrophy scores, and vaginal pH. Women with aromatase inhibitor-treated breast cancer exhibit reduced proliferation and altered steroid hormone receptor staining intensity in the vagina, which are related to clinical signs of vaginal atrophy. Although these effects are most probably attributable to estrogen suppression, a possible local inhibition of aromatase cannot be ruled out.

The impact of nandrolone decanoate and growth hormone on biosynthesis of steroids in rats

Growth hormone (GH) and anabolic androgenic steroids (AAS) are commonly used in sports communities. Several studies have suggested an association between GH and AAS. We have investigated the impact of GH in rats treated with nandrolone decanoate (ND). Male Wistar rats received ND (15mg/kg) every third day during three weeks and were subsequently treated with recombinant human GH (1.0IU/kg) for ten consecutive days. Plasma samples were collected and peripheral organs (i.e. heart, liver, testis and thymus) were dissected and weighed. Concentration of thirteen endogenous steroids was measured in the rat plasma samples using high specificity LC–MS/MS methods. Seven steroids were detected and quantified, and concentrations of estrone, testosterone, and androstenedione were significantly different among the groups, while concentrations of pregnenolone, DHEA, 17-hydroxyprogesterone and corticosterone were not altered. Administration of rhGH alone altered the plasma steroid distribution, and the results demonstrated significantly increased concentrations of plasma estrone as well as decreased concentrations of testosterone and androstenedione in the ND-treated rats. Administration of rhGH to ND-pretreated rats did not reverse the alteration of the steroid distribution induced by ND. Administration of ND decreased the weight of the thymus, and addition of rhGH did not reverse this reduction. However, rhGH administration induced an enlargement of thymus. Taken together, the plasma steroid profile differed in the four groups, i.e. control, AAS, rhGH and the combination of AAS and rhGH treatment.

Endocrine markers for identifying prolificacy potential and predicting fetal number in goats

Identifying prolificacy potential and determination of fetal number during pregnancy for proper care and management of the pregnant goats bearing multiple fetuses and achieving the benefits out of multiple births are essential for sustainable goat farming. Our objectives were (1) to examine prolificacy potential in goats by using pituitary response to gonadotrophin releasing hormone (GnRH) challenge test, (2) to investigate hormonal profiles for the prediction of fetal number in pregnant goats and (3) to find out the most reliable timing of blood sampling for discriminating prolificacy trait and differentiating the goats bearing single, twin and triplet fetuses. In first experiment (GnRH challenge test), plasma FSH concentrations were significantly higher (P<0.01) among the goats belonging to triplet vs. twin vs. single kidding size groups after GnRH administration. Multivariate stepwise discriminant function analysis recognized that one blood sampling at 220min after GnRH administration can be used to distinguish prolificacy potential in goats. In second experiment, plasma progesterone levels were significantly higher (P<0.01) in goats bearing triplet vs. twin vs. single fetus between day 84 and 21 prior to parturition. Plasma estrone sulphate concentrations were found to be higher (P<0.05) in does bearing multiple fetuses than the does bearing single fetus between day 126 and 28 prior to parturition. A single blood sampling at day 63 prior to parturition was the most probable suitable time for discriminating kidding size by using plasma progesterone as marker.