Endogenous Estrogen Research Articles

THU576 Anabolic Androgenic Steroid Abuse In Cis-gender Female Bodybuilder

Abstract Disclosure: E.M. Niedzialkowska: None. D. Shelden: None. Introduction: Anabolic androgenic steroids (AAS) are used in bodybuilders to increase muscle mass. Abuse has surged as they are regarded as potent image enhancement drugs. There are a variety of illegal AAS available. Their true content is often unknown and dosing regimens frequently include concurrent use of multiple hormonally active agents. Use among female body builders is rarely reported. Having significantly lower levels of natural testosterone, females may be more susceptible to side effects and toxicity associated with AAS abuse. Clinical case: 36 year old cis-gender female presented to the Endocrinology clinic for evaluation of fatigue. The patient worked as a personal trainer at a gym and began participating in bodybuilding competitions. A year prior to the visit the patient was started on a steroid regimen by a friend at the gym. The patient’s regimen included testosterone cypionate (250mg-350mg a week) and trenbolone acetate. Anastozole was added to limit conversion to estrogen but was not administered on a regular basis. The patient reported no gender dysphoria. She has not had a menstrual period since she started the AAS. The patient was also diagnosed with acute kidney injury at the time of AAS initiation and further work up showed negative ANA, C3, C4, normal UA and protein/creatinine ratio. Her kidney injury was deemed to be related to NSAID and testosterone use. At the time of the visit laboratory results were significant for testosterone of >1500 ng/dl (N 240-1080), IGF-1 359 ng/ml (N 63-223), LH <0.1 mUI/ml (N>0.6), FSH <0.5 mUI/ml (N>1.4), estradiol 47 pg/ml (N 21-251), prolactin 10.8 ng/ml (N 3-30), hemoglobin 17.4 g/dl (N 12-15.1), platelets 416 bil/L (150-400), TSH 0.75 uIU/ml (N 0.4-4.5), creatinine 1.33 mg/dl (N 0.5-1.1), eGFR 53 ml/min/1.73m2. The patient's testosterone regimen was gradually decreased to 100 mg weekly with plans to further decrease the dose and with close follow up and monitoring of gonadotropins. Treatment to stimulate endogenous estrogen production may be necessary despite her current value being within normal limits as this may be a function of peripheral conversion of exogenous testosterone. Conclusion: AAS abuse is infrequent among cis-gender females. Its use in female bodybuilders increases muscle strength and athletic performance. Exogenous administration of synthetic testosterone results in negative feedback on the hypothalamic-pituitary axis, inhibiting GnRH, leading to inhibition of FSH and LH production leading to amenorrhea in females. AAS has also been associated with kidney injury with reports from animal studies suggesting testosterone induced podocyte damage and apoptosis. The steroid regimens used by bodybuilders differ and include multiple hormonally active agents. Its abuse among cis-gender women is uncommon and further research is needed to evaluate its toxicity among this group. Presentation Date: Thursday, June 15, 2023

Gender and sex in the development and progression of renal diseases

Sex-based disparities in nephrology have been a historically understudied area. In nephrology, gender differences exist with regard to the epidemiology, evolution and prognosis of chronic kidney disease (CKD). In some cases, these differences run contrary to the general population trends. We discuss such gender and sex disparities, including differing impact of traditional and novel risk factors, as well as hormonal factors, all of them potentially influencing propensity, progression and biochemical and psychological aspects of CKD. The factors involved in this gender disparity may include diet, kidney and glomerular size, differences in glomerular hemodynamics, and the direct effects of sex hormones. The progression rate of many renal diseases is affected by sex. In polycystic kidney disease, membranous nephropathy, immunoglobulin A nephropathy, and “chronic renal disease of unknown etiology”, men progress at a faster rate to end-stage renal failure than women do. In many, but not all, animal models of renal disease, estrogens slow progression rate. Animal and experimental studies have tried to offer further mechanistic explanations for gender differences in disease progression. It has been suggested that the gender dimorphism of CKD progression may represent the effects of the interaction of circulating steroids with specific kidney receptors. Endogenous estrogens have in general been considered to have anti-fibrotic and anti-apoptotic effects on the kidney. On the other hand, the faster decline of kidney function in men has been attributed to the specific pro-apoptotic and pro-fibrotic properties of androgens.

ICI 182,780 Attenuates Selective Upregulation of Uterine Artery Cystathionine β-Synthase Expression in Rat Pregnancy.

Endogenous hydrogen sulfide (H2S) produced by cystathionine β-synthase (CBS) and cystathionine-γ lyase (CSE) has emerged as a novel uterine vasodilator contributing to pregnancy-associated increases in uterine blood flow, which safeguard pregnancy health. Uterine artery (UA) H2S production is stimulated via exogenous estrogen replacement and is associated with elevated endogenous estrogens during pregnancy through the selective upregulation of CBS without altering CSE. However, how endogenous estrogens regulate uterine artery CBS expression in pregnancy is unknown. This study was conducted to test a hypothesis that endogenous estrogens selectively stimulate UA CBS expression via specific estrogen receptors (ER). Treatment with E2β (0.01 to 100 nM) stimulated CBS but not CSE mRNA in organ cultures of fresh UA rings from both NP and P (gestational day 20, GD20) rats, with greater responses to all doses of E2β tested in P vs. NP UA. ER antagonist ICI 182,780 (ICI, 1 µM) completely attenuated E2β-stimulated CBS mRNA in both NP and P rat UA. Subcutaneous injection with ICI 182,780 (0.3 mg/rat) of GD19 P rats for 24 h significantly inhibited UA CBS but not mRNA expression, consistent with reduced endothelial and smooth muscle cell CBS (but not CSE) protein. ICI did not alter mesenteric and renal artery CBS and CSE mRNA. In addition, ICI decreased endothelial nitric oxide synthase mRNA in UA but not in mesenteric or renal arteries. Thus, pregnancy-augmented UA CBS/H2S production is mediated by the actions of endogenous estrogens via specific ER in pregnant rats.

Expression Kinetics of Vitellogenin Gene in Estradiol-17β Induced <i>Catla catla</i>

Vitellogenin (Vtg) is the yolk precursor protein in fish and is synthesized in the liver under estradiol-17β (E2) stimulation. In all oviparous animals, Vtg is synthesized as a response to endogenous estrogen in females in the breeding season. It also could be induced exogenously by E2 in males and juveniles. In the current study the inducibility of Vtg gene in Indian major carp, Catla catla was tested. A semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) assay was developed for kinetic study of Vtg mRNA level in C. catla after primary and secondary inductions by E2. It was found that the level of Vtg-specific mRNA was highest following 12 h post treatment in primary induction, and after 1 d post treatment in secondary induction. There was a sharp decrease in Vtg mRNA level on day one and day two in primary and secondary induction, respectively. Thus the ‘memory effect’ of vitellogenin induction by E2 in catla could not be confirmed.

Migraine During Pregnancy

Migraine without aura reportedly improves during pregnancy, and this phenomenon is attributed to the sustained elevation and lack of fluctuations in the endogenous estrogen levels. In contrast, the occurrence of aura (such as visual symptoms) has been reported in patients having migraine with aura. Furthermore, the risk of gestational hypertension and preeclampsia is demonstrably significantly higher in patients with migraine than in healthy individuals. Hence, recognizing that pregnant women with migraine are at high risk of developing cardiovascular diseases is crucial.

Molecular Docking Studies and In-silico ADMET Profile Analysis of Triphala Plant constituents Morin and 9, 10-anthraquinone as Potential Inhibitors of human Estrogen Receptor Alpha

The expanding global burden of cancer demands novel treatment options. Herbal medicine offers a viable alternative to conventional cancer treatment. Breast cancer is frequently diagnosed cancer among women all over the world. Normal breast cells and specific breast cancer cells containestrogen and progesterone receptors. Estrogen and progesterone bind to receptors and stimulate cancer cell proliferation and expansion with growth factors (e.g., oncogenes and mutated gene suppressors). Tamoxifen, raloxifene, andtoremifene are among the most frequently used drugs for breast cancer, whereas estrogen continues to be produced in breast cancer cells. These medications primarily function against theestrogen binding to theestrogenreceptors on these cells. Protein-ligand interaction plays a major role in structural drug design. In this study, the molecular interactions between theHuman estrogen receptor alpha (PDB ID: 2IOK), and the two ligands isolated from Triphala Ayurvedic formulation morin, and 9,10-anthraquinone, an endogenous estrogen receptor ligand, estradiol, and the three economically available breast cancer drug, tamoxifen, raloxifene, and toremifene using the AutodockVina software tool. The ADMET properties of these substances were determinedusing popular web-based software tools that include preADMET, admetSAR, Molinspiration, and SwissADME.The present available anti-cancer drugs have so many side effects. The present work is aimed at determining the efficacy ofestrogen receptor inhibitors and the safety profile of morin, anthraquinone molecules isolated from Triphalapolyherbal formulation by in-silico methods. The binding energies (Kcal/mol) of ligands with human estrogen receptor were calculated as follows: morin (-9.0), 9,10-anthraquinone (-8.7), estradiol (-10.1), tamoxifen (-9.6), raloxifene (-9.8) and toremifene (-8.9). The resultssupported the drug-like properties of the molecules tested and they are likely to have a therapeutic effect.Further,in vivo and pre-clinical trials of the most active compound are also worthwhile for producing effective inhibitors.

Sex Hormones, the Stool Microbiome, and Subclinical Atherosclerosis in Women With and Without HIV.

Cardioprotective roles of endogenous estrogens may be particularly important in women with HIV, who have reduced estrogen exposure and elevated cardiovascular disease risk. The gut microbiome metabolically interacts with sex hormones, but little is known regarding possible impact on cardiovascular risk. To analyze potential interplay of sex hormones and gut microbiome in cardiovascular risk. Among 197 postmenopausal women in the Women's Interagency HIV Study, we measured 15 sex hormones in serum and assessed the gut microbiome in stool. Presence of carotid artery plaque was determined (B-mode ultrasound) in a subset (n = 134). We examined associations of (i) sex hormones and stool microbiome, (ii) sex hormones and plaque, and (iii) sex hormone-related stool microbiota and plaque, adjusting for potential confounders. Participant median age was 58 years and the majority were living with HIV (81%). Sex hormones (estrogens, androgens, and adrenal precursors) were associated with stool microbiome diversity and specific species, similarly in women with and without HIV. Estrogens were associated with higher diversity, higher abundance of species from Alistipes, Collinsella, Erysipelotrichia, and Clostridia, and higher abundance of microbial β-glucuronidase and aryl-sulfatase orthologs, which are involved in hormone metabolism. Several hormones were associated with lower odds of carotid artery plaque, including dihydrotestosterone, 3α-diol-17G, estradiol, and estrone. Exploratory mediation analysis suggested that estrone-related species, particularly from Collinsella, may mediate the protective association of estrone with plaque. Serum sex hormones are significant predictors of stool microbiome diversity and composition. The gut microbiome may play a role in estrogen-related cardiovascular protection.

27-Hydroxycholesterol represses G9a expression via oestrogen receptor alpha in breast cancer.

27-hydroxycholesterol (27-HC) is a cholesterol metabolite and the first discovered endogenous selective estrogen receptor modulator (SERM) that has been shown to have proliferative and metastatic activity in breast cancer. However, whether 27-HC metabolite modulates the epigenetic signatures in breast cancer and its progression remains unclear. The current study, reports that 27-HC represses the expression of euchromatic histone lysine methyltransferase G9a, further reducing di-methylation at H3K9 in a subset of genes. We also observed reduced occupancy of ERα at the G9a promoter, indicating that 27-HC negatively regulates the ERα occupancy on the G9a promoter and functions as a transcriptional repressor. Further, ChIP-sequencing for the H3K9me2 mark has demonstrated that 27-HC treatment reduces the H3K9me2 mark on subset of genes linked to cancer progression, proliferation, and metastasis. We observed upregulation of these genes following 27-HC treatment which further confirms the loss of methylation at these genes. Immunohistochemical analysis with breast cancer patient tissues indicated a positive correlation between G9a expression and CYP7B1, a key enzyme of 27-HC catabolism. Overall, this study reports that 27-HC represses G9a expression via ERα and reduces the levels of H3K9me2 on a subset of genes, including the genes that aid in breast tumorigenesis and invasion further, increasing its expression in the breast cancer cells.

Number of children and cognitive function among Chinese menopausal women: The mediating role of depressive symptoms and social participation

ObjectivesThis study examined the association between number of children and cognitive function and its possible hormone and psychosocial pathways in Chinese menopausal women. MethodsWe analyzed data from the China Health and Retirement Longitudinal Study (CHALRS), including 4803 menopausal women. Ordinary least squares (OLS) regression modeling and structural equation modeling (SEM) were applied to explore the association between number of children and cognitive function and the potential mechanisms. ResultsOverall, the median number of biological children was three among participants. The cognitive function score decreased significantly with increasing numbers of children [β = −0.547, 95 % confidence interval (CI): −0.677, −0.416]. There was a significant interaction between number of children and residence (P = 0.003). Compared with older women with three or less children, women with more than three children had worse cognitive function (β = −0.798, 95 % CI: −1.081, −0.514). Mediation analysis verified that depressive symptoms and social participation partially mediate the associations between the number of children and cognitive function. LimitationsFirst, because of the cross-sectional design, our study was unable to make causal inferences. Second, information about endogenous estrogen exposure was not collected in CHARLS. Third, recall bias may exist due to the use of self-reported data. ConclusionOur results indicated that a higher number of children is associated with an increased risk for cognitive impairment. We suggest paying special attention to mental and social health among women with multiple children (>3).

Differences in Cholesterol Metabolism, Hepato-Intestinal Aging, and Hepatic Endocrine Milieu in Rats as Affected by the Sex and Age.

Age and sex influence serum cholesterol levels, but the underlying mechanisms remain unclear. To investigate further, we measured cholesterol, precursors (surrogate synthesis markers), degradation products (oxysterols and bile acid precursors) in serum, the liver, jejunum, and ileum, as well as serum plant sterols (intestinal absorption markers) in male and female Wistar rats (4 and 24 months old). The analysis of histomorphometric and oxidative stress parameters (superoxide dismutase, catalase, glutathione-related enzyme activities, lipid peroxide, and protein carbonyl concentrations) in the liver and jejunum offered further insights into the age- and sex-related differences. The hepatic gene expression analysis included AR, ERα, and sex-specific growth hormone-regulated (Cyp2c11 and Cyp2c12) and thyroid-responsive (Dio1, Tbg, and Spot 14) genes by qPCR. We observed age-related changes in both sexes, with greater prominence in females. Aged females had significantly higher serum cholesterol (p < 0.05), jejunum cholesterol (p < 0.05), and serum plant sterols (p < 0.05). They exhibited poorer hepato-intestinal health compared with males, which was characterized by mild liver dysfunction (hydropic degeneration, increased serum ALT, p < 0.05, and decreased activity of some antioxidant defense enzymes, p < 0.05), mononuclear inflammation in the jejunal lamina propria, and age-related decreases in jejunal catalase and glutathione peroxidase activity (p < 0.05). Aged females showed increased levels of 27-hydroxycholesterol (p < 0.05) and upregulated ERα gene expression (p < 0.05) in the liver. Our study suggests that the more significant age-related increase in serum cholesterol in females is associated with poorer hepato-intestinal health and increased jejunal cholesterol absorption. The local increase in 27-hydroxycholesterol during aging might reduce the hepatoprotective effects of endogenous estrogen in the female liver.

Effect of Tofu Supplementation on Endogenous Estrogen Levels and Urinary Incontinence in Female Spayed Dogs: A Randomized, Controlled Clinical Study

Effect of Tofu Supplementation on Endogenous Estrogen Levels and Urinary Incontinence in Female Spayed Dogs: A Randomized, Controlled Clinical Study

Exposure to endogenous and exogenous sex hormones and reproductive history influence prognosis in women with ALS.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with a higher incidence in men suggesting an influence of sex steroids. Our objective was to investigate past exposure to endogenous and synthetic steroids in female ALS patients and controls. We administered a questionnaire to 158 postmenopausal women (75 ALS patients and 83 controls). We calculated reproductive time span (RTS), lifetime endogenous estrogen (LEE) and progesterone exposures (LPE), oral contraceptive pill (OCP) use, and reproductive history. ALS patients showed shorter LEE and LPE, a lower proportion of breast cancer, and 11% showed no history of pregnancies vs. 4% of controls. Odds ratios (ORs) showed that <17 y of LEE and a delayed menarche (>13 y) constitute risk factors for ALS [OR = 2.1 (95% confidence interval {CI}, 1.08-4.2); and OR = 2.4 (95% CI, 1.1-5.1) respectively]. According to Cox survival analysis, for each year the LEE increased over 17 y, it was independently associated with longer survival [hazard ratio (HR) = 0.37 (95% CI, 0.16-0.85)] after adjusting for smoking, age and site of onset. Multivariate regression analysis demonstrated that for each month using OCP for longer than 40 mo increased the risk of ALS [adjusted OR = 4.1 (95% CI, 1.2-13.8)]. Thus, longer exposure to endogenous female sex steroids increased survival and reduced ALS susceptibility. In contrast, longer exposure to synthetic sex steroids showed a negative impact by reducing the production of endogenous female sex steroids or due to crossover with other steroid receptors. Given the neuroprotective effects of sex steroids, we suggest that abnormalities of neuroendocrine components may alter motor function in women with ALS.

Membrane estrogen receptor-α contributes to female protection against high-fat diet-induced metabolic disorders.

Estrogen Receptor α (ERα) is a significant modulator of energy balance and lipid/glucose metabolisms. Beyond the classical nuclear actions of the receptor, rapid activation of intracellular signaling pathways is mediated by a sub-fraction of ERα localized to the plasma membrane, known as Membrane Initiated Steroid Signaling (MISS). However, whether membrane ERα is involved in the protective metabolic actions of endogenous estrogens in conditions of nutritional challenge, and thus contributes to sex differences in the susceptibility to metabolic diseases, remains to be clarified. Male and female C451A-ERα mice, harboring a point mutation which results in the abolition of membrane localization and MISS-related effects of the receptor, and their wild-type littermates (WT-ERα) were maintained on a normal chow diet (NCD) or fed a high-fat diet (HFD). Body weight gain, body composition and glucose tolerance were monitored. Insulin sensitivity and energy balance regulation were further investigated in HFD-fed female mice. C451A-ERα genotype had no influence on body weight gain, adipose tissue accumulation and glucose tolerance in NCD-fed mice of both sexes followed up to 7 months of age, nor male mice fed a HFD for 12 weeks. In contrast, compared to WT-ERα littermates, HFD-fed C451A-ERα female mice exhibited: 1) accelerated fat mass accumulation, liver steatosis and impaired glucose tolerance; 2) whole-body insulin resistance, assessed by hyperinsulinemic-euglycemic clamps, and altered insulin-induced signaling in skeletal muscle and liver; 3) significant decrease in energy expenditure associated with histological and functional abnormalities of brown adipose tissue and a defect in thermogenesis regulation in response to cold exposure. Besides the well-characterized role of ERα nuclear actions, membrane-initiated ERα extra-nuclear signaling contributes to female, but not to male, protection against HFD-induced obesity and associated metabolic disorders in mouse.

Psoralen prevents the inactivation of estradiol and treats osteoporosis via covalently targeting HSD17B2.

Psoralea corylifolia L. seeds (P. corylifolia), popularly known as Buguzhi in traditional Chinese medicine, are often used to treat osteoporosis in China. Psoralen (Pso) is the key anti-osteoporosis constituent in P. corylifolia, however, its targets and mechanism of action are still unclear. The purpose of this study was to explore the interaction between Pso and 17-β hydroxysteroid dehydrogenase type 2 (HSD17B2), an estrogen synthesis-related protein that inhibits the inactivation of estradiol (E2) to treat osteoporosis. Tissue distribution of Pso was analyzed by in-gel imaging after oral administration of an alkynyl-modified Pso probe (aPso) in mice. The target of Pso in the liver was identified and analyzed using chemical proteomics. Co-localization and cellular thermal shift assays (CETSA) were used to verify the key action targets. To detect the key pharmacophore of Pso, the interaction of Pso and its structural analogs with HSD17B2 was investigated by CETSA, HSD17B2 activity assay, and in-gel imaging determination. Target competitive test, virtual docking, mutated HSD17B2 activity, and CETSA assay were used to identify the binding site of Pso with HSD17B2. A mouse model of osteoporosis was established by ovariectomies, and the efficacy of Pso in vivo was confirmed by micro-CT, H&E staining, HSD17B2 activity, and bone-related biochemical assays. Pso regulated estrogen metabolism by targeting HSD17B2 in the liver, with the α, β-unsaturated ester in Pso being the key pharmacophore. Pso significantly suppressed HSD17B2 activity by irreversibly binding to Lys236 of HSD17B2 and preventing NAD+ from entering the binding pocket. In vivo studies in ovariectomized mice revealed that Pso could inhibit HSD17B2 activity, prevent the inactivation of E2, increase levels of endogenous estrogen, improve bone metabolism-related indices, and play a role in anti-osteoporosis. Pso covalently binds to Lys236 of HSD17B2 in hepatocytes to prevent the inactivation of E2, thereby aiding in the treatment of osteoporosis.

BPA; An Endocrine Disruptor Induced Biochemical Changes and Histopathological Damage in the Kidneys of Rats (Rattus Norvegicus)

Background: Xenoestrogens are chemical compounds that are similar to estrogen in effect but not in structure. Bisphenol A is an endocrine disruptor, that mimics the action of endogenous estrogen and activates the estrogen receptor. It is produced in large volumes and incorporated in many plastic industries worldwide. BPA is extensively used in food and beverages. The ubiquitous and extensive use of BPA containing products results in high human exposure, and its effects on the human body are of great concern. The aim of the present study was to evaluate the effects of BPA on biochemical and histopathological parameters of the kidney. Material and Methods: Forty adult male rats were assigned into five groups of eight rats each. One group was served as a control and other groups were treated with BPA. Rats were administered orally with different doses of BPA 10mg/Kg and 25mg/Kg for 6 and 12 weeks, respectively. All doses of BPA were dissolved in corn oil and orally administered to rats. After 6 and 12 weeks, blood and kidney samples were collected for evaluation of biochemical parameters and histopathological analyses. Results: Serum levels of urea and creatinine were significantly increased, and uric acid levels in serum were increased but not significantly. The biochemical parameters variations were confirmed by histopathological investigations. BPA induced toxicity may lead to harmful health effects. Conclusion: Results showed that the oral administration of BPA significantly affects biochemical parameters and renal tissue architecture.

Skeletal Muscle Endogenous Estrogen Production Ameliorates the Metabolic Consequences of a High-Fat Diet in Male Mice.

The role of skeletal muscle estrogen and its ability to mitigate the negative impact of a high-fat diet (HFD) on obesity-associated metabolic impairments is unknown. To address this, we developed a novel mouse model to determine the role of endogenous 17β-estradiol (E2) production in males in skeletal muscle via inducible, skeletal muscle-specific aromatase overexpression (SkM-Arom↑). Male SkM-Arom↑ mice and littermate controls were fed a HFD for 14 weeks prior to induction of SkM-Arom↑ for a period of 6.5 weeks. Glucose tolerance, insulin action, adipose tissue inflammation, and body composition were assessed. Indirect calorimetry and behavioral phenotyping experiments were performed using metabolic cages. Liquid chromatography mass spectrometry was used to determine circulating and tissue (skeletal muscle, hepatic, and adipose) E2 and testosterone concentrations. SkM-Arom↑ significantly increased E2 in skeletal muscle, circulation, the liver, and adipose tissue. SkM-Arom↑ ameliorated HFD-induced hyperglycemia, hyperinsulinemia, impaired glucose tolerance, adipose tissue inflammation, and reduced hepatic lipid accumulation while eliciting skeletal muscle hypertrophy. Enhanced skeletal muscle aromatase activity in male mice induces weight loss, improves metabolic and inflammatory outcomes and mitigates the negative effects of a HFD. Additionally, our data demonstrate for the first time skeletal muscle E2 has anabolic effects on the musculoskeletal system.

Endogenous estrogen receptor modulating oxysterols and breast cancer prognosis: Results from the MARIE patient cohort

Background27-hydroxycholesterol (HC) and 25-HC were identified as endogenous selective estrogen receptor modulators (SERMs) and estrogen receptor (ER) modulators, respectively. They are hypothesized to play a role in multiple physiologic processes and pathologies, including breast cancer development and progression.MethodsWe evaluated circulating 27-HC and 25-HC, and outcomes following a breast cancer diagnosis in 2282 women from the MARIE study over median follow-up of 11.6 years. 27-HC and 25-HC were quantified by liquid chromatography–mass spectrometry. We calculated hazard ratios (HR) and 95% confidence intervals [CI] using multivariable Cox Proportional Hazards regression.ResultsWe observed no associations between 27-HC and breast cancer prognosis overall. Associations between 27-HC and survival differed by circulating estradiol concentrations and endocrine therapy, but not by hormone receptor status. Among women with estradiol levels below the median (0.08 nM), 27-HC was associated with higher risk of all-cause mortality (HRlog2 = 1.80 [1.20–2.71]) and breast cancer-specific mortality (HRlog2 = 1.95 [1.14-3.31]). No associations were observed in women with estradiol levels above the median. Higher 25-HC levels were associated with lower risk of recurrence (HRlog2 = 0.87 [0.77-0.98]).ConclusionAssociations between 27-HC and breast cancer prognosis varied by circulating estradiol levels and endocrine therapy. Less consistent results were observed for 25-HC.

Urolithin A: A promising selective estrogen receptor modulator and 27-hydroxycholesterol attenuator in breast cancer.

27-hydroxycholesterol (27-HC) is an oxysterol that acts as an endogenous selective estrogen receptor modulator (SERM), and its adverse effects on breast cancer via the estrogen receptor (ER) have provided new insights into the pathology of cholesterol-linked breast cancer. Our earlier in vitro experiments showed that the methanolic extract of pomegranate could exhibit SERM properties and compete with 27-HC. The major constituents of pomegranate are ellagitannins and ellagic acid, which are converted into urolithins by the colonic microbiota. In recent years, urolithins, especially urolithin A (UA) and urolithin B (UB), have been reported to have a plethora of advantageous effects, including antiproliferative and estrogenic activities. In this study, we attempted to determine the potential of urolithins in antagonizing and counteracting the adverse effects of 27-HC in breast cancer cells. Our findings suggested that UA had an antiproliferative capacity and attenuated the proliferative effects of 27-HC, resulting in subsequent loss of membrane potential and apoptosis in breast cancer cells. Further, UA induced estrogen response element (ERE) transcriptional activity and modulated estrogen-responsive genes, exhibiting a SERM-like response concerning receptor binding. Our in vivo hollow fiber assay results showed a loss of cell viability in breast cancer cells upon UA consumption, as well as a reduction in 27-HC-induced proliferative activity. Additionally, it was shown that UA did not induce uterine proliferation or alter blood biochemical parameters. Based on these findings, we can conclude that UA has the potential to act as a potent estrogen receptor alpha (ERα) modulator and 27-HC antagonist. UA is safe to consume and is very well tolerated. This study further opens up the potential of UA as ER modulator and its benefits in estrogen-dependent tissues.

Age at menopause and all-cause and cause-specific dementia: a prospective analysis of the UK Biobank cohort.

Are there associations between natural or surgical menopause and incident dementia by age at menopause? Compared to age at menopause of 46-50 years, earlier natural menopause (≤40 and 41-45 years) was related to higher risk of all-cause dementia, while a U-shape relationship was observed between age at surgical menopause and risk of dementia. Menopause marks the end of female reproductive period. Age at menopause reflects the length of exposure to endogenous estrogen. Evidence on the association between age at natural, surgical menopause, and risk of dementia has been inconsistent. A population-based cohort study involving 160080 women who participated in the UK Biobank study. Women with no dementia at baseline, and had no missing data on key exposure variables and covariates were included. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% CIs on the association of categorical menopause age with incident all-cause dementia, Alzheimer's disease (AD) and vascular dementia (VD). Restricted cubic splines were used to model the non-linear relationship between continuous age at natural, surgical menopause, and risk of dementia. In addition, we analyzed the interaction effect of ever-used menopausal hormone therapy (MHT) at baseline, income level, leisure activities, and age at menopause on risk of dementia. Compared to women with age at menopause of 46-50 years, women with earlier natural menopause younger than 40 years (1.36, 1.01-1.83) and 41-45 years (1.19, 1.03-1.39) had a higher risk of all-cause dementia, while late natural menopause >55 years was linked to lower risk of dementia (0.83, 0.71-0.98). Compared to natural menopause, surgical menopause was associated with 10% higher risk of dementia (1.10, 0.98-1.24). A U-shape relationship was observed between surgical menopause and risk of dementia. Women with surgical menopause before age 40 years (1.94, 1.38-2.73) and after age 55 years (1.65, 1.21-2.24) were both linked to increased risk of all-cause dementia. Women with early natural menopause without ever taking MHT at baseline had an increased risk of AD. Also, in each categorized age at the menopause level, higher income level or higher number of leisure activities was linked to a lowers risk of dementia. Menopausal age was based on women's self-report, which might cause recall bias. Women who experienced natural menopause or had surgical menopause at an earlier age need close monitoring and engagement for preventive health measures to delay the development of dementia. This work was supported by the Start-up Foundation for Scientific Research in Shandong University (202099000066), Science Fund Program for Excellent Young Scholars of Shandong Provence (Overseas) (2022HWYQ-030), and the National Natural Science Foundation of China (82273702). There are no competing interests. N/A.

Associations of Circulating Estrogens and Estrogen Metabolites with Fecal and Oral Microbiome in Postmenopausal Women in the Ghana Breast Health Study.

The human fecal and oral microbiome may play a role in the etiology of breast cancer through modulation of endogenous estrogen metabolism. This study aimed to investigate associations of circulating estrogens and estrogen metabolites with the fecal and oral microbiome in postmenopausal African women. A total of 117 women with fecal (N = 110) and oral (N = 114) microbiome data measured by 16S rRNA gene sequencing, and estrogens and estrogen metabolites data measured by liquid chromatography tandem mass spectrometry were included. The outcomes were measures of the microbiome and the independent variables were the estrogens and estrogen metabolites. Estrogens and estrogen metabolites were associated with the fecal microbial Shannon index (global P < 0.01). In particular, higher levels of estrone (β = 0.36, P = 0.03), 2-hydroxyestradiol (β = 0.30, P = 0.02), 4-methoxyestrone (β = 0.51, P = 0.01), and estriol (β = 0.36, P = 0.04) were associated with higher levels of the Shannon index, while 16alpha-hydroxyestrone (β = -0.57, P < 0.01) was inversely associated with the Shannon index as indicated by linear regression. Conjugated 2-methoxyestrone was associated with oral microbial unweighted UniFrac as indicated by MiRKAT (P < 0.01) and PERMANOVA, where conjugated 2-methoxyestrone explained 2.67% of the oral microbial variability, but no other estrogens or estrogen metabolites were associated with any other beta diversity measures. The presence and abundance of multiple fecal and oral genera, such as fecal genera from families Lachnospiraceae and Ruminococcaceae, were associated with several estrogens and estrogen metabolites as indicated by zero-inflated negative binomial regression. Overall, we found several associations of specific estrogens and estrogen metabolites and the fecal and oral microbiome. IMPORTANCE Several epidemiologic studies have found associations of urinary estrogens and estrogen metabolites with the fecal microbiome. However, urinary estrogen concentrations are not strongly correlated with serum estrogens, a known risk factor for breast cancer. To better understand whether the human fecal and oral microbiome were associated with breast cancer risk via the regulation of estrogen metabolism, we conducted this study to investigate the associations of circulating estrogens and estrogen metabolites with the fecal and oral microbiome in postmenopausal African women. We found several associations of parent estrogens and several estrogen metabolites with the microbial communities, and multiple individual associations of estrogens and estrogen metabolites with the presence and abundance of multiple fecal and oral genera, such as fecal genera from families Lachnospiraceae and Ruminococcaceae, which have estrogen metabolizing properties. Future large, longitudinal studies to investigate the dynamic changes of the fecal and oral microbiome and estrogen relationship are needed.