Effects of estrogen and raloxifene on synaptic density in the hippocampal CA1 region of ovariectomized rats.

INTRODUCTION: The CA1 region of the hippocampus has an important role in learning and memory. It has been shown that estrogen deficiency may reduce the synaptic density in the region and that hormone replacement therapy may attenuate the reduction. OBJECTIVES: This study aimed to evaluate the effects of estrogen and raloxifene on the synaptic density profile in the CA1 region of the hippocampus in ovariectomized rats. METHODS: Sixty ovariectomized three-month-old virgin rats were randomized into six groups (n = 10). Treatments started either three days (early treatment) or sixty days (late treatment) after ovariectomy. The groups received propylene glycol vehicle (0.5 mL/animal/day), equine conjugated estrogens (50 µg/animal/day), or raloxifene (3 mg/kg/day) either early or late after ovariectomy. The drugs were administered orally by gavage for 30 days. At the end of the treatments, the animals were anesthetized and transcardially perfused with ether and saline solution. The brains were removed and prepared for analysis under transmission electron microscopy and later fixed. RESULTS: Results showed a significant increase in the synaptic density profile of the hippocampal CA1 region in both the early estrogen (0.534 ± 0.026 µ/m2) and the early raloxifene (0.437 ± 0.012 µ/m2) treatment groups compared to the early or late vehicle-treated control groups (0.338 ± 0.038 µ/m2 and 0.277 ± 0.015 µ/m2 respectively). CONCLUSIONS: The present data suggest that the raloxifene effect may be lower than that of estrogen, even early or late treatment, on synaptic density in the hippocampus.

Effects of Estradiol/Micronized Progesterone vs. Conjugated Equine Estrogens/Medroxyprogesterone Acetate on Breast Cancer Gene Expression in Healthy Postmenopausal Women.

Recent studies suggest estradiol (E2)/natural progesterone (P) confers less breast cancer risk compared with conjugated equine estrogens (CEE)/synthetic progestogens. We investigate if differences in the regulation of breast cancer-related gene expression could provide some explanation. This study is a subset of a monocentric, 2-way, open observer-blinded, phase 4 randomized controlled trial on healthy postmenopausal women with climacteric symptoms (ClinicalTrials.gov; EUCTR-2005/001016-51). Study medication was two 28-day cycles of sequential hormone treatment with oral 0.625 mg CEE and 5 mg of oral medroxyprogesterone acetate (MPA) or 1.5 mg E2 as percutaneous gel/day with the addition of 200 mg oral micronized P. MPA and P were added days 15-28/cycle. Material from two core-needle breast biopsies in 15 women in each group was subject to quantitative PCR (Q-PCR). The primary endpoint was a change in breast carcinoma development gene expression. In the first eight consecutive women, RNA was extracted at baseline and after two months of treatment and subjected to microarray for 28856 genes and Ingenuity Pathways Analysis (IPA) to identify risk factor genes. Microarray analysis showed 3272 genes regulated with a fold-change of >±1.4. IPA showed 225 genes belonging to mammary-tumor development function: 198 for CEE/MPA vs. 34 for E2/P. Sixteen genes involved in mammary tumor inclination were subject to Q-PCR, inclining the CEE/MPA group towards an increased risk for breast carcinoma compared to the E2/P group at a very high significance level (p = 3.1 × 10-8, z-score 1.94). The combination of E2/P affected breast cancer-related genes much less than CEE/MPA.

Differing effects of oral conjugated equine estrogen and transdermal estradiol on vitamin D metabolism in postmenopausal women: a 4-year longitudinal study.

OBJECTIVE: The aim of this study was to examine the effect of either conjugated equine estrogen or transdermal estradiol on vitamin D metabolism in postmenopausal women. METHODS: Twenty-five women from the Kronos Early Estrogen Prevention Study who were randomized to conjugated equine estrogen 0.45 mg/d and 20 women who were treated with transdermal estradiol 50 mg/d (patch replaced weekly) were analyzed in the present study. All participants received micronized progesterone for 12 days per month. RESULTS: There was no significant treatment effect on serum total 25-hydroxyvitamin D over 48 months in either study group, and there were no significant differences between treatment arms. In contrast, at 12 months, directly measured free 25-hydroxyvitamin D was significantly higher in the transdermal estradiol group than in the conjugated equine estrogen group. Directly measured free 25-hydroxyvitamin D subsequently increased significantly from 12 to 48 months in both treatment arms. Calculated free 25-hydroxyvitamin D was also significantly higher in the transdermal estradiol group at 36 months. Vitamin D-binding protein decreased significantly in both treatment groups from 12 to 48 months, but at 48 months, least square mean values were no different based on treatment assignment. CONCLUSIONS: Directly measured free 25-hydroxyvitamin D levels, but not serum total 25-hydroxyvitamin D levels, are different within the first 12 months of estrogen replacement depending on the preparation. However, this difference is transient, in that there were no differences at 36 or 48 months. These findings suggest that there may be a short-term benefit to prescribing transdermal estradiol for women who are either vitamin D deficient or vitamin D insufficient.

Epigenetic and transcriptome responsiveness to ER modulation by tissue selective estrogen complexes in breast epithelial and breast cancer cells.

Selective estrogen receptor modulators (SERMs), including the SERM/SERD bazedoxifene (BZA), are used to treat postmenopausal osteoporosis and may reduce breast cancer (BCa) risk. One of the most persistent unresolved questions regarding menopausal hormone therapy is compromised control of proliferation and phenotype because of short- or long-term administration of mixed-function estrogen receptor (ER) ligands. To gain insight into epigenetic effectors of the transcriptomes of hormone and BZA-treated BCa cells, we evaluated a panel of histone modifications. The impact of short-term hormone treatment and BZA on gene expression and genome-wide epigenetic profiles was examined in ERαneg mammary epithelial cells (MCF10A) and ERα+ luminal breast cancer cells (MCF7). We tested individual components and combinations of 17ß-estradiol (E2), estrogen compounds (EC10) and BZA. RNA-seq for gene expression and ChIP-seq for active (H3K4me3, H3K4ac, H3K27ac) and repressive (H3K27me3) histone modifications were performed. Our results show that the combination of BZA with E2 or EC10 reduces estrogen-mediated patterns of histone modifications and gene expression in MCF-7ERα+ cells. In contrast, BZA has minimal effects on these parameters in MCF10A mammary epithelial cells. BZA-induced changes in histone modifications in MCF7 cells are characterized by altered H3K4ac patterns, with changes at distal enhancers of ERα-target genes and at promoters of non-ERα bound proliferation-related genes. Notably, the ERα target gene GREB1 is the most sensitive to BZA treatment. Our findings provide direct mechanistic-based evidence that BZA induces epigenetic changes in E2 and EC10 mediated control of ERα regulatory programs to target distinctive proliferation gene pathways that restrain the potential for breast cancer development.

Microscopic Evaluation of Ovarian Surface Epithelium Following Treatment with Conjugated Estrogens in a Mouse Model.

BACKGROUND: This study was designed to evaluate the effect of different concentrations of conjugated equine estrogens (CEE) on the ovarian epithelium of female CD1 mice. METHODS: Twenty-four female mice at 7 months with irregular estrus cycles were randomly divided into four groups of 6 mice each. Group one was considered as a control group and received a daily dose of 0.5ml of propylene glycol, for three weeks, while those in the treatment groups received a daily dose of 14µg/kg, 28µg/kg and 56µg/kg conjugated equine estrogens, respectively. RESULTS: The results from this study showed a strong correlation between elevated concentrations of CEE and histological changes in ovarian surface epithelium (OSE). They also showed that administration of high-dose estrogen created the conditions for excessive proliferation of OSE which may progress into the development of cysts in the ovaries. CONCLUSION: This study concluded that high concentrations of CEE may increase the chances of developing epithelial ovarian cancer.

Effect of Chamomile Vaginal Gel on the Sexual Function in Postmenopausal Women: A Double-Blind Randomized Controlled Trial.

BACKGROUND: Female sexual dysfunction (FSD) is a common complaint among postmenopausal women, which is largely because of the genitourinary syndrome in these women (GSM). AIM: Considering the phytoestrogenic effects of chamomile, the present study was primarily aimed to investigate the effect of chamomile vaginal gel on the sexual function of postmenopausal women. The side effects of these drugs were evaluated as a secondary outcome of the study. METHODS: This randomized double-blind clinical trial and placebo-controlled study was conducted on postmenopausal women with sexual dysfunction (FSFI ≤26.55). To this aim, 96 postmenopausal women were randomly assigned into three groups (n = 32 each) including women receiving (i) chamomile vaginal gel 5%, (ii) conjugated estrogen vaginal cream, and (iii) placebo vaginal gel, for 12 weeks (ie, every night in the first 2 weeks, and 2 nights per week in the next 10 weeks, each night 1 g was used). The sexual function was measured using female sexual function index (FSFI) before and after the intervention. Data analysis was performed by chi-square, one-way ANOVA, descriptive statistics, analysis of covariance (ANCOVA), and paired t test using SPSS software version 22. P < .05 was considered statistically significant. OUTCOMES: The main study outcome measure was evaluate the effects of vaginal administration of chamomile gel in comparison with conjugated estrogen cream and placebo gel on postmenopausal FSD using the FSFI. RESULTS: The findings showed that chamomile vaginal gel in compared to placebo vaginal gel caused a significant improvement in all six sexual function domains and the total FSFI score (effect size = +2.9 [95% CI, +2.1 to +3.6], P < .001). Also, there was no significant difference between the chamomile vaginal gel and conjugated estrogen vaginal cream groups in terms of the total score and all sub-domains of sexual function with the exception of orgasm (effect size = +0.13 [95% CI, -0.36 to +0.63], P = .02) and sexual satisfaction (effect size = 0 [95% CI, -0.49 to +0.49], P = .04). Two women in the chamomile group and one in the placebo group experienced a burning sensation (P = .345). CLINICAL IMPLICATIONS: This treatment can be considered as a treatment option for postmenopausal women with sexual dysfunction who have contraindications to the use of hormone therapy. STRENGTHS & LIMITATIONS: This study is the first study to investigate the effectiveness of chamomile vaginal gel on sexual function in postmenopausal women. However, in this study, treatment duration was 12 weeks and no follow up was performed beyond this time CONCLUSION: Based on the results of this study, the use of vaginal chamomile gel improved sexual function in postmenopausal women. Bosak Z, Iravani M, Moghimipour E, et al. Effect of Chamomile Vaginal Gel on the Sexual Function in Postmenopausal Women: A Double-Blind Randomized Controlled Trial. J Sex Med 2022;19:983-994.

Impact of 6 month conjugated equine estrogen versus estradiol-treatment on biomarkers and enriched gene sets in healthy mammary tissue of non-human primates.

OBJECTIVE: To identify distinctly regulated gene markers and enriched gene sets in breast tissue of cynomolgus monkeys (Macaca fascicularis) treated for six months with either conjugated equine estrogens (CEE) or estradiol (E2) by analysis of corresponding mRNA levels of genes associated with breast development, carcinogenesis, apoptosis and immune regulation. Additionally, translation of three nuclear markers was analyzed. METHODS: RNA from breast biopsies and necropsies was isolated from two independent study trials from Ethun et al. (CEE) and Foth et al. (E2) after 6 month of treatment duration. RNA was subjected to qRT-PCR and MicroArray analysis. Immunohistochemical stainings were performed for the estrogen receptor alpha subunit (ERa), the progesterone receptor (PGR) and the proliferation marker Ki67. RESULTS: We identified a total of 36 distinctly enriched gene sets. Thirty-one were found in the CEE treatment group and five were found in the E2 treatment group, with no overlap. Furthermore, two individual genes IGFBP1 and SGK493 were upregulated in CEE treated animals. Additional targeted qRT-PCR analysis of ten specific estrogen-related genes showed upregulation of three genes (TFF1, PGR and GREB1) after CEE treatment, respectively one gene (TFF1) after E2 treatment. Immunohistochemical stains of breast biopsies showed a significant increase in expression of the PGR marker after CEE treatment. CONCLUSIONS: In this study we identified enriched gene sets possibly induced by CEE or E2 treatment in various processes associated with cancer biology and immunology. This preliminary translational data supports the concept that different estrogen types have different effects on healthy breast tissue and may help generate hypotheses for future research.

Premarin Reduces Neurodegeneration and Promotes Improvement of Function in an Animal Model of Spinal Cord Injury.

Spinal cord injury (SCI) causes significant mortality and morbidity. Currently, no FDA-approved pharmacotherapy is available for treating SCI. Previously, low doses of estrogen (17ß-estradiol, E2) were shown to improve the post-injury outcome in a rat SCI model. However, the range of associated side effects makes advocating its therapeutic use difficult. Therefore, this study aimed at investigating the therapeutic efficacy of Premarin (PRM) in SCI. PRM is an FDA-approved E2 (10%) formulation, which is used for hormone replacement therapy with minimal risk of serious side effects. The effects of PRM on SCI were examined by magnetic resonance imaging, immunofluorescent staining, and western blot analysis in a rat model. SCI animals treated with vehicle alone, PRM, E2 receptor antagonist (ICI), or PRM + ICI were graded in a blinded way for locomotor function by using the Basso-Beattie-Bresnahan (BBB) locomotor scale. PRM treatment for 7 days decreased post-SCI lesion volume and attenuated neuronal cell death, inflammation, and axonal damage. PRM also altered the balance of pro- and anti-apoptotic proteins in favor of cell survival and improved angiogenesis and microvascular growth. Increased expression of estrogen receptors (ERs) ERα and ERß following PRM treatment and their inhibition by ER inhibitor indicated that the neuroprotection associated with PRM treatment might be E2-receptor mediated. The attenuation of glial activation with decreased inflammation and cell death, and increased angiogenesis by PRM led to improved functional outcome as determined by the BBB locomotor scale. These results suggest that PRM treatment has significant therapeutic implications for the improvement of post-SCI outcome.

Co-Opting Host Receptors for Targeted Delivery of Bioconjugates-From Drugs to Bugs.

Bioconjugation has allowed scientists to combine multiple functional elements into one biological or biochemical unit. This assembly can result in the production of constructs that are targeted to a specific site or cell type in order to enhance the response to, or activity of, the conjugated moiety. In the case of cancer treatments, selectively targeting chemotherapies to the cells of interest limit harmful side effects and enhance efficacy. Targeting through conjugation is also advantageous in delivering treatments to difficult-to-reach tissues, such as the brain or infections deep in the lung. Bacterial infections can be more selectively treated by conjugating antibiotics to microbe-specific entities; helping to avoid antibiotic resistance across commensal bacterial species. In the case of vaccine development, conjugation is used to enhance efficacy without compromising safety. In this work, we will review the previously mentioned areas in which bioconjugation has created new possibilities and advanced treatments.

Effect of conjugated estrogens and bazedoxifene on glucose, energy and lipid metabolism in obese postmenopausal women.

OBJECTIVE: Combining conjugated estrogens (CE) with the selective estrogen receptor modulator bazedoxifene (BZA) is a novel, orally administered menopausal therapy. We investigated the effect of CE/BZA on insulin sensitivity, energy metabolism, and serum metabolome in postmenopausal women with obesity. DESIGN: Randomized, double-blind, crossover pilot trial with washout was conducted at Pennington Biomedical Research Center. Eight postmenopausal women (age 50-60 years, BMI 30-40 kg/m2) were randomized to 8 weeks CE/BZA or placebo. Primary outcome was insulin sensitivity (hyperinsulinemic-euglycemic clamp). Secondary outcomes included body composition (DXA); resting metabolic rate (RMR); substrate oxidation (indirect calorimetry); ectopic lipids (1H-MRS); fat cell size, adipose and skeletal muscle gene expression (biopsies); serum inflammatory markers; and serum metabolome (LC/MS). RESULTS: CE/BZA treatment produced no detectable effect on insulin sensitivity, body composition, ectopic fat, fat cell size, or substrate oxidation, but resulted in a non-significant increase in RMR (basal: P = 0.06; high-dose clamp: P = 0.08) compared to placebo. CE/BZA increased serum high-density lipoprotein (HDL)-cholesterol. CE/BZA also increased serum diacylglycerol (DAG) and triacylglycerol (TAG) species containing long-chain saturated, mono- and polyunsaturated fatty acids (FAs) and decreased long-chain acylcarnitines, possibly reflecting increased hepatic de novo FA synthesis and esterification into TAGs for export into very low-density lipoproteins, as well as decreased FA oxidation, respectively (P < 0.05). CE/BZA increased serum phosphatidylcholines, phosphatidylethanolamines, ceramides, and sphingomyelins, possibly reflecting the increase in serum lipoproteins (P < 0.05). CONCLUSIONS: A short treatment of obese postmenopausal women with CE/BZA does not alter insulin action or ectopic fat but increases serum markers of hepatic de novo lipogenesis and TAG production.

Effects of Hormone Therapy on Heart Fat and Coronary Artery Calcification Progression: Secondary Analysis From the KEEPS Trial.

Background Heart fats (epicardial and paracardial adipose tissue [PAT]) are greater after menopause. Endogenous estrogen may regulate these fat depots. We evaluated the differential effects of hormone therapy formulations on heart fat accumulations and their associations with coronary artery calcification (CAC) progression in recently menopausal women from KEEPS (Kronos Early Estrogen Prevention Study). Methods and Results KEEPS was a multicenter, randomized, placebo-controlled trial of the effects of 0.45 mg/d oral conjugated equine estrogens and 50 µg/d transdermal 17ß-estradiol, compared with placebo, on 48-month progression of subclinical atherosclerosis among 727 early menopausal women. CAC progression was defined if baseline CAC score was 0 and 48-month CAC score was >0 or if baseline CAC score was >0 and <100 and annualized change in CAC score was ≥10. Of 727 KEEPS participants, 474 (mean age: 52.7 [SD: 2.6]; 78.1% white) had computed tomography-based heart fat and CAC measures at both baseline and 48 months. Compared with women on placebo, women on oral conjugated equine estrogens were less likely to have any increase in epicardial adipose tissue (odds ratio for oral conjugated equine estrogens versus placebo: 0.62 [95% CI, 0.40-0.97]; P=0.03). PAT did not change in any group. Changes in epicardial adipose tissue and PAT did not differ by treatment group. CAC increased in 14% of participants. The assigned treatment modified the association between PAT changes and CAC progression (P=0.02) such that PAT increases were associated with CAC increases only in the transdermal 17ß-estradiol group. Conclusions In recently menopausal women, oral conjugated equine estrogens may slow epicardial adipose tissue accumulation, whereas transdermal 17ß-estradiol may increase progression of CAC associated with PAT accumulation. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00154180.

Current Evidence of the Oncological Benefit-Risk Profile of Hormone Replacement Therapy.

Hormone replacement therapy (HRT) remains the most effective treatment for menopausal symptoms and has been shown to prevent bone loss and fracture. The progestogen is added to provide endometrial protection in women with an intact uterus. After the publication of the initial WHI (Women's Health Initiative) results in 2002 reporting an overall increased risk of breast cancer, many women discontinued HRT. Despite the re-analysis of the results by subgroups of patients and updates with extended follow-up, much controversy remains, which we will analyze later in the text. Different types of estrogen or progestogen, as well as different formulations, doses, and durations, may play a role in HRT's effects on breast tissue. Evidence states that conjugated equine estrogen (CEE), compared to estro-progestin therapy, shows a better profile risk (HR 0.79, CI 0.65-0.97) and that, among different type of progestins, those structurally related to testosterone show a higher risk (RR 3.35, CI 1.07-10.4). Chronic unopposed endometrial exposure to estrogen increases the risk of endometrial hyperplasia and cancer, whereas the association with progestins, especially in continuous combined regimen, seems to reduce the risk (RR 0.71, CI 0.56-0.90). HRT was also associated with a protective effect on colon cancer risk (HR 0.61, CI 0.42-0.87). Data about ovarian and cervical cancer are still controversial.

Effect of Bazedoxifene and Conjugated Estrogen (Duavee) on Breast Cancer Risk Biomarkers in High-Risk Women: A Pilot Study.

Interventions that relieve vasomotor symptoms while reducing risk for breast cancer would likely improve uptake of chemoprevention for perimenopausal and postmenopausal women. We conducted a pilot study with 6 months of the tissue selective estrogen complex bazedoxifene (20 mg) and conjugated estrogen (0.45 mg; Duavee) to assess feasibility and effects on risk biomarkers for postmenopausal breast cancer. Risk biomarkers included fully automated mammographic volumetric density (Volpara), benign breast tissue Ki-67 (MIB-1 immunochemistry), and serum levels of progesterone, IGF-1, and IGFBP3, bioavailable estradiol and testosterone. Twenty-eight perimenopausal and postmenopausal women at increased risk for breast cancer were enrolled: 13 in cohort A with baseline Ki-67 < 1% and 15 in cohort B with baseline Ki-67 of 1% to 4%. All completed the study with > 85% drug adherence. Significant changes in biomarkers, uncorrected for multiple comparisons, were a decrease in mammographic fibroglandular volume (P = 0.043); decreases in serum progesterone, bioavailable testosterone, and IGF-1 (P < 0.01), an increase in serum bioavailable estradiol (P < 0.001), and for women from cohort B a reduction in Ki-67 (P = 0.017). An improvement in median hot flash score from 15 at baseline to 0 at 6 months, and menopause-specific quality-of-life total, vasomotor, and sexual domain scores were also observed (P < 0.001). Given the favorable effects on risk biomarkers and patient reported outcomes, a placebo-controlled phase IIB trial is warranted.

Hepatic steroid sulfatase critically determines estrogenic activities of conjugated equine estrogens in human cells in vitro and in mice.

Conjugated equine estrogens (CEEs), whose brand name is Premarin, are widely used as a hormone-replacement therapy (HRT) drug to manage postmenopausal symptoms in women. Extracted from pregnant mare urine, CEEs are composed of nearly a dozen estrogens existing in an inactive sulfated form. To determine whether the hepatic steroid sulfatase (STS) is a key contributor to the efficacy of CEEs in HRT, we performed estrogen-responsive element (ERE) reporter gene assay, real-time PCR, and UPLC-MS/MS to assess the STS-dependent and inflammation-responsive estrogenic activity of CEEs in HepG2 cells and human primary hepatocytes. Using liver-specific STS-expressing transgenic mice, we also evaluated the effect of STS on the estrogenic activity of CEEs in vivo We observed that CEEs induce activity of the ERE reporter gene in an STS-dependent manner and that genetic or pharmacological inhibition of STS attenuates CEE estrogenic activity. In hepatocytes, inflammation enhanced CEE estrogenic activity by inducing STS gene expression. The inflammation-responsive estrogenic activity of CEEs, in turn, attenuated inflammation through the anti-inflammatory activity of the active estrogens. In vivo, transgenic mice with liver-specific STS expression exhibited markedly increased sensitivity to CEE-induced estrogenic activity in the uterus resulting from increased levels of liver-derived and circulating estrogens. Our results reveal a critical role of hepatic STS in mediating the hormone-replacing activity of CEEs. We propose that caution needs to be applied when Premarin is used in patients with chronic inflammatory liver diseases because such patients may have heightened sensitivity to CEEs due to the inflammatory induction of STS activity.

Equilin in conjugated equine estrogen increases monocyte-endothelial adhesion via NF-κB signaling.

The adhesion of monocytes to endothelial cells, which is mediated by adhesion molecules, plays a crucial role in the onset of atherosclerosis. Conjugated equine estrogen, which is widely used for estrogen-replacement therapy, contains both estrone sulfate and various nonhuman estrogens, including equilin. To investigate the association between various estrogen types and atherosclerosis risk, we examined their effect on adhesion-molecule expression in human umbilical vein endothelial cells (HUVECs). In estrogen-treated HUVECs, the mRNA and protein expression levels of adhesion molecules were quantified by real-time polymerase chain reaction and enzyme immunoassay. Additionally, a flow-chamber system was used to assess the effects of estrogens on the adherence of U937 monocytoid cells to HUVECs. Equilin, but not 17ß-estradiol (E2) or other types of estrogen, significantly increased the mRNA (P < 0.01) and protein (P < 0.05) expression of the adhesion molecules E-selectin and intercellular adhesion molecule-1 as compared with levels in controls. Equilin treatment increased the adherence of U937 monocytoid cells to HUVECs relative to the that in the control (P < 0.05), decreased estrogen receptor (ER)ß expression, and increased the expression of proteins involved in nuclear factor kappa-B (NF-κB) activation relative to levels in controls. Furthermore, the accumulation of NF-κB subunit p65 in HUVEC nuclei was promoted by equilin treatment. By contrast, E2 treatment neither increased the number of adhered monocytoid cells to HUVECs nor altered the expression of ERß or NF-κB-activating proteins. Our findings suggest that in terms of the adhesion of monocytes at the onset of atherosclerosis, E2 may be preferable for estrogen-replacement therapy. Further studies comparing equilin treatment with that of E2 are needed to investigate their differential impacts on atherosclerosis.

Effects of bazedoxifene/conjugated estrogens on reproductive endocrinology and reproductive tract ultrasonographic appearance in premenopausal women: a preliminary study.

Bazedoxifene (BZA) paired with conjugated estrogens (CE) is the first tissue selective estrogen receptor complex (TSEC) approved by the United States Food and Drug Administration for the treatment of menopausal symptoms. Clinical trials in menopausal women and in premenopausal murine models of endometriosis have demonstrated safety and efficacy, however, the impact of BZA/CE on premenopausal women is not known. Here we report a case series study in premenopausal women assessing effects of BZA/CE on reproductive hormones, and uterine/ovarian ultrasonographic appearance. After one monitoring cycle, five subjects underwent daily administration of BZA/CE (20 mg/0.45 mg) for 12 weeks, and were followed for 4 weeks after treatment. Uterine/ovarian morphology was assessed with ultrasound, and endocrinologic function with ovulation prediction kits and serum assessment of reproductive hormones throughout the menstrual cycle. All subjects demonstrated an LH surge on the medication; interestingly there was a significant decrease in luteinizing hormone level during treatment compared to posttreatment values. BZA/CE was well-tolerated in premenopausal women and did not induce clinically relevant reproductive hormone changes, endometrial alterations, or abnormal ovarian folliculogenesis.

27-Hydroxycholesterol, an Endogenous SERM, and Risk of Fracture in Postmenopausal Women: A Nested Case-Cohort Study in the Women's Health Initiative.

27-Hydroxycholesterol (27HC) is a purported, novel endogenous SERM. In animal models, 27HC has an anti-estrogen effect in bone, and 17ß-estradiol mitigates this effect. 27HC in relation to fracture risk has not been investigated in humans. Depending on the level of bioavailable 17ß-estradiol (bioE2 ), 27HC may increase fracture risk in postmenopausal women and modify the fracture risk reduction from menopausal hormone therapy (MHT). To test these a priori hypotheses, we conducted a nested case-cohort study of 868 postmenopausal women within the Women's Health Initiative Hormone Therapy (WHI-HT) trials. The WHI-HT tested conjugated equine estrogens versus placebo and separately conjugated equine estrogens plus progestin versus placebo. Fracture cases were 442 women who had an adjudicated incident hip or clinical vertebral fracture during the WHI-HT follow-up. The subcohort included 430 women randomly selected at WHI-HT baseline, four of whom had a subsequent fracture. Of the 868 women, 266 cases and 219 non-cases were assigned to the placebo arms. Cox models estimated hazard ratios for incident fracture in relation to pre-randomization circulating levels of 27HC and 27HC/bioE2 molar ratio. Models adjusted for age, race/ethnicity, total cholesterol, bioE2 , sex hormone-binding globulin, 25-hydroxyvitamin D, diabetes, osteoporosis, prior MHT use, BMI, falls history, and prior fracture. In women assigned to placebo arms, those in the middle and the highest tertiles of 27HC/bioE2 had an up to 1.9-fold (95% confidence intervals, 1.25 to 2.99) greater risk of fracture than women in the lowest tertile. In women assigned to MHT arms, fracture risk increased with continuous 27HC/bioE2 levels but not with categorical levels. 27HC levels alone were not associated with fracture risk. 27HC and 27HC/bioE2 did not modify the fracture risk reduction from MHT. In postmenopausal women, circulating levels of 27HC relative to bioE2 may identify those at increased risk of fracture. © 2018 American Society for Bone and Mineral Research.

Comparison of the antioxidant effects of equine estrogens, red wine components, vitamin E, and probucol on low-density lipoprotein oxidation in postmenopausal women.

OBJECTIVE: Oxidized low-density lipoprotein (LDL) seems to play an important role in the etiology of atherosclerosis. To further study this, we performed two studies: (1) we determined the ability of 10 estrogen components of the drug, conjugated equine estrogen (CEE), trans-resveratrol (t-resveratrol) and quercetin (red wine components), trolox (vitamin E analog), and probucol (a serum cholesterol-lowering drug) to delay or prevent the oxidation of plasma LDL isolated from untreated postmenopausal women, and (2) we assessed the effect of long-term (>1 year) estrogen replacement therapy and hormone replacement therapy on LDL oxidation by ex vivo methods. DESIGN: For the in vivo study, three groups of postmenopausal women were selected based on whether they were on long-term CEE therapy (group A: 0.625 mg CEE; n = 21), on combination CEE plus progestogen therapy (group B: 0.625 mg CEE + 5.0 mg medroxyprogesterone acetate, 10 days; n = 20), or not on any hormone therapy (group C; n = 37). For the in vitro study, only LDL samples obtained from group C were used. The kinetics of LDL oxidation were measured by continuously monitoring the formation of conjugated dienes followed by determination of the lag time. RESULTS: All compounds tested protected the LDL from oxidative damage. The relative antioxidant potency of estrogen components was generally greater than that of the other compounds. The minimum dose (nmoles) required to double the lag time from the control lag time of 57 ±â€Š2 min was 0.47 for 17ß-dihydroequilenin, 17α-dihydroequilenin, Δ-estrone; 0.6 to 0.7 for Δ-17ß-estradiol, equilenin, and quercetin; 0.9 for 17ß-dihydroequilin and 17α-dihydroequilin; 1.3 for equilin, estrone, 17ß-estradiol, 17α-estradiol; 1.4 for trolox; 1.9 for probucol; and 3.0 for t-resveratrol. The data from the in vivo study indicate that after long-term estrogen replacement therapy (group A) and hormone replacement therapy (group B), the LDL was significantly (p < 0.01) protected (higher lag time) against oxidation compared with the control (group C). There was no difference between groups A and B. CONCLUSIONS: The oxidation of LDL isolated from postmenopausal women is inhibited differentially by various estrogens and other antioxidants. The unique ring B unsaturated estrogen components of CEE were the most potent, and t-resveratrol, the red wine component, was the least potent. Long-term CEE or CEE + medroxyprogesterone acetate administration to postmenopausal women protects the LDL against oxidation to the same extent. These combined data support the hypothesis that some of the cardioprotective benefits associated with CEE therapy and perhaps red wine consumption may be due to the ability of their components to protect LDL against oxidative modifications.

Postmenopausal hormone treatment alters neural pathways but does not improve verbal cognitive function.

OBJECTIVE: Cognitive outcomes in trials of postmenopausal hormone treatment have been inconsistent. Differing outcomes may be attributed to hormone formulation, treatment duration and timing, and differential cognitive domain effects. We previously demonstrated treatment benefits on visual cognitive function. In the present study, we describe the effects of hormone treatment on verbal outcomes in the same women, seeking to understand the effects of prior versus current hormone treatment on verbal function. METHODS: This is a cross-sectional evaluation of 57 women (38 hormone users [25 prior long-term users and 13 current users] and 19 never-users). Hormone users took identical formulations of estrogen or estrogen + progestin (0.625 mg/d conjugated equine estrogens with or without medroxyprogesterone acetate) for at least 10 years, beginning within 2 years of menopause. Women were evaluated with tests of verbal function and functional magnetic resonance imaging (fMRI) of a verbal discrimination task. RESULTS: All women scored similarly on assessments of verbal function (Hopkins Verbal Learning Test and a verbal discrimination task performed during the fMRI scanning session); however, women ever treated with hormones had more left inferior frontal (T = 3.72; P < 0.001) and right prefrontal cortex (T = 3.53; P < 0.001) activation during the verbal task. Hormone-treated women performed slightly worse on the verbal discrimination task (mean accuracy 81.72 ±â€Š11.57 ever-treated, 85.30 ±â€Š5.87 never-treated, P = 0.14), took longer to respond (mean reaction time 1.10 ±â€Š0.17 s ever-treated, 1.02 ±â€Š0.11 never-treated, P = 0.03), and remembered fewer previously viewed words (mean accuracy 62.21 ±â€Š8.73 ever-treated, 65.45 ±â€Š7.49 never-treated, P = 0.18). Increased posterior cingulate activity was associated with longer response times (R = 0.323, P = 0.015) and worse delayed verbal recall (R = -0.328, P = 0.048), suggesting that increased activation was associated with less efficient cognitive processing. We did not detect between group differences in activation in the left prefrontal cortex, superior frontal cortex, thalamus, or occipital/parietal junction. CONCLUSIONS: Although current and past hormone treatment was associated with differences in neural pathways used during verbal discrimination, verbal function was not higher than never-users.

Long-Term Administration of Conjugated Estrogen and Bazedoxifene Decreased Murine Fecal ß-Glucuronidase Activity Without Impacting Overall Microbiome Community.

Conjugated estrogens (CE) and Bazedoxifene (BZA) combination is used to alleviate menopause-associated symptoms in women. CE+BZA undergo first-pass-metabolism in the liver and deconjugation by gut microbiome via ß-glucuronidase (GUS) enzyme inside the distal gut. To date, the impact of long-term exposure to CE+BZA on the gut microbiome or GUS activity has not been examined. Our study using an ovariectomized mouse model showed that CE+BZA administration did not affect the overall cecal or fecal microbiome community except that it decreased the abundance of Akkermansia, which was identified as a fecal biomarker correlated with weight gain. The fecal GUS activity was reduced significantly and was positively correlated with the abundance of Lactobacillaceae in the fecal microbiome. We further confirmed in Escherichia coli K12 and Lactobacillus gasseri ADH that Tamoxifen-, 4-hydroxy-Tamoxifen- and Estradiol-Glucuronides competed for GUS activity. Our study for the first time demonstrated that long-term estrogen supplementation directly modulated gut microbial GUS activity. Our findings implicate that long-term estrogen supplementation impacts composition of gut microbiota and microbial activity, which affects estrogen metabolism in the gut. Thus, it is possible to manipulate such activity to improve the efficacy and safety of long-term administered estrogens for postmenopausal women or breast cancer patients.