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Purpose of Review: The purpose of this literature review was to determine if medications used to treat osteoporosis are also effective for treating osteoarthritis (OA). Recent Findings: A total of 40 relevant articles were identified. Studies were categorized into those (1) discussing estrogen and selective estrogen receptor modulators (SERMs), (2) bisphosphonates, (3) parathyroid hormone (PTH) analogs, and (4) denosumab, and (5) prior review articles. A large amount of evidence suggests that estrogen and SERMs are effective at reducing OA symptoms and disease progression. Evidence suggests that bisphosphonates, the most common medications used to treat osteoporosis, can reduce OA symptoms and disease progression. In vivo studies suggest that PTH analogs may improve the cartilage destruction associated with OA; however, few human trials have examined its use for OA. Denosumab is approved to treat osteoporosis, bone metastases, and certain types of breast cancer, but little study has been done with respect to its effect on OA. Summary: The current evidence indicates that medications used to treat osteoporosis are also effective for treating OA. Estrogen, SERMs, and bisphosphonates have the most potential as OA therapies. Less is known regarding the effectiveness of PTH analogs and denosumab in OA, and more research is needed. [ABSTRACT FROM AUTHOR]

Osteoporosis is the most prevalent bone disease in the US. Once diagnosed, osteoporosis requires ongoing management; therefore, primary care providers are vital in managing both primary and secondary fracture prevention. Safe, efficacious, and economical medications are available, but osteoporosis remains underdiagnosed and undertreated. Bisphosphonates, selective estrogen receptor modulators (raloxifene), conjugated estrogens/bazedoxifene, estrogen therapy/hormone therapy, parathyroid hormone analogues, RANK ligand inhibitors (denosumab), sclerostin inhibitors (romosozumab), and calcitonin are all drugs or drug classes commonly used to treat osteoporosis that are discussed in this article. [ABSTRACT FROM AUTHOR]

Endocrine therapy (ET) of selective estrogen receptor modulators (SERMs), selective estrogen receptor downregulators (SERDs), and aromatase inhibitors (AIs) has been used as the gold standard treatment for hormone-receptor-positive (HR+) breast cancer. Despite its clinical benefits, approximately 30% of patients develop ET resistance, which remains a major clinical challenge in patients with HR+ breast cancer. The mechanisms of ET resistance mainly focus on mutations in the ER and related pathways; however, other targets still exist from ligand-independent ER reactivation. Moreover, mutations in the ER that confer resistance to SERMs or AIs seldom appear in SERDs. To date, little research has been conducted to identify a critical target that appears in both SERMs/SERDs and AIs. In this study, we conducted comprehensive transcriptomic and proteomic analyses from two cohorts of The Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) to identify the critical targets for both SERMs/SERDs and AIs of ET resistance. From a treatment response cohort with treatment response for the initial ET regimen and an endocrine therapy cohort with survival outcomes, we identified candidate gene sets that appeared in both SERMs/SERDs and AIs of ET resistance. The candidate gene sets successfully differentiated progress/resistant groups (PD) from complete response groups (CR) and were significantly correlated with survival outcomes in both cohorts. In summary, this study provides valuable clinical implications for the critical roles played by candidate gene sets in the diagnosis, mechanism, and therapeutic strategy for both SERMs/SERDs and AIs of ET resistance for the future. [ABSTRACT FROM AUTHOR]

Purpose: Current concepts regarding estrogen and its mechanistic effects on breast cancer in women are evolving. This article reviews studies that address estrogen-mediated breast cancer development, the prevalence of occult tumors at autopsy, and the natural history of breast cancer as predicted by a newly developed tumor kinetic model.Methods: This article reviews previously published studies from the authors and articles pertinent to the data presented.Results: We discuss the concepts of adaptive hypersensitivity that develops in response to long-term deprivation of estrogen and results in both increased cell proliferation and apoptosis. The effects of menopausal hormonal therapy on breast cancer in postmenopausal women are interpreted based on the tumor kinetic model. Studies of the administration of a tissue selective estrogen complex in vitro, in vivo, and in patients are described. We review the various clinical studies of breast cancer prevention with selective estrogen receptor modulators and aromatase inhibitors. Finally, the effects of the underlying risk of breast cancer on the effects of menopausal hormone therapy are outlined.Discussion: The overall intent of this review is to present data supporting recent concepts, discuss pertinent literature, and critically examine areas of controversy. [ABSTRACT FROM AUTHOR]

Our previous study demonstrated that the bone protective actions of herbal medicine Rhizoma Drynariae (Gusuibu, RD) were mainly mediated by flavonoid phytoestrogens via estrogen receptors, raising concerns about the safety of using RD as it may induce estrogen-like risk-benefit profile and interact with other ER ligands, such as selective estrogen receptor modulators (SERMs), when coadministered. The present study evaluated the estrogenic activities of RD and its potential interaction with tamoxifen, a SERM, in estrogen-sensitive tissues by using mature ovariectomized (OVX) rats and ER-positive cells. Similar to but weaker than tamoxifen, RD at its clinical dose dramatically ameliorated OVX-induced changes in bone and dopamine metabolism-related markers in OVX rats. However, tamoxifen, but not RD, induced uterotrophic effects. No significant alteration in mammary gland was observed in OVX rats treated with RD, which was different from the inhibitory actions of tamoxifen. The two-way ANOVA results indicated the interactions between RD and tamoxifen in the bone, brain, and uterus of OVX rats while RD did not alter their responses to tamoxifen. Our results demonstrate that RD selectively exerts estrogenic actions in a different manner from tamoxifen. Moreover, RD interacts with tamoxifen without altering its effects in OVX rats. [ABSTRACT FROM AUTHOR]

Our previous study demonstrated that the bone protective actions of herbal medicine Rhizoma Drynariae (Gusuibu, RD) were mainly mediated by flavonoid phytoestrogens via estrogen receptors, raising concerns about the safety of using RD as it may induce estrogen-like risk-benefit profile and interact with other ER ligands, such as selective estrogen receptor modulators (SERMs), when coadministered. The present study evaluated the estrogenic activities of RD and its potential interaction with tamoxifen, a SERM, in estrogen-sensitive tissues by using mature ovariectomized (OVX) rats and ER-positive cells. Similar to but weaker than tamoxifen, RD at its clinical dose dramatically ameliorated OVX-induced changes in bone and dopamine metabolism-related markers in OVX rats. However, tamoxifen, but not RD, induced uterotrophic effects. No significant alteration in mammary gland was observed in OVX rats treated with RD, which was different from the inhibitory actions of tamoxifen. The two-way ANOVA results indicated the interactions between RD and tamoxifen in the bone, brain, and uterus of OVX rats while RD did not alter their responses to tamoxifen. Our results demonstrate that RD selectively exerts estrogenic actions in a different manner from tamoxifen. Moreover, RD interacts with tamoxifen without altering its effects in OVX rats.

More and more menopausal women use Danggui Buxue Tang (DBT) for relieving their symptoms. Concerns for its safety have been raised as it contains phytoestrogen and acts via estrogen receptors (ERs). Our study aimed to determine whether DBT could selectively exert estrogenic activities and interact with tamoxifen in bone, brain, uterus, and breast by using ovariectomized (OVX) rats and ER-positive cells. In OVX rats, DBT induced a 31.4% increase in bone mineral density and restored the mRNA expression of dopamine biomarker in striatum, 3.32-fold for tyrosine hydrolase (p < .001) and 0.21-fold for dopamine transporter (p < .001), which was similar to tamoxifen; tamoxifen, but not DBT, increased uterus weight and Complement component 3 expression by more than twofold (p < .001); unlike tamoxifen, DBT induced mild proliferation in mammary gland. Two-way ANOVA indicated the interactions between them in OVX rats (p < .05) but DBT did not alter the responses to tamoxifen. DBT stimulated proliferation or differentiation and estrogen response element in MCF-7, MG-63, Ishikawa, and SHSY5Y cells and altered the effects of tamoxifen. In summary, DBT exerted estrogenic effects in tissue-selective manner, which was different from tamoxifen. DBT interacted with tamoxifen but did not significantly alter its effects in OVX rats. [ABSTRACT FROM AUTHOR]

Androgen deprivation therapy (ADT) has been widely prescribed for patients with advanced prostate cancer (PC) to control key signaling pathways via androgen receptor (AR) and AR-collaborative transcriptional factors; however, PC gradually acquires a lethal phenotype and results in castration-resistant PC (CRPC) during ADT. Therefore, new therapeutic strategies are required in clinical practice. In addition, ARs; estrogen receptors (ERs; ERRα and ERRβ); and estrogen-related receptors (ERRs; ERR, ERR, and ERR ) have been reported to be involved in the development or regulation of PC. Recent investigations have revealed the role of associated molecules, such as KLF5, FOXO1, PDGFA, VEGF-A, WNT5A, TGFb1, and micro-RNA 135a of PC, via ERs and ERRs. Selective ER modulators (SERMs) have been developed. Recently, estrogen and androgen blockade (EAB) using a combination of toremifene and ADT has been demonstrated to improve biochemical recurrence rate in treatment-naïve bone metastatic PC. In the future, the suitability of ADT alone or EAB for individuals may be evaluated by making clinical decisions on the basis of information obtained from RT-PCR, gene-panel, or liquid biopsy to create a "personalized medicine" or "precision medicine". In this review, we summarize ER and ERR signaling pathways, molecular diagnosis, and SERMs as candidates for advanced PC treatment. [ABSTRACT FROM AUTHOR]

The objective of the study was to carry out docking studies of isoflavone derivatives and examine their binding efficiencies to the ligand binding domain of ERα using Autodock program. A series of isoflavone derivatives were computationally designed and optimized with the AutoDock Vina software to investigate the interactions between the target compounds and the amino acid residues of the ERα.. In silico docking studies were carried out using AutoDock Vina, based on the Lamarckian genetics algorithm principle. The results showed that all the selected isoflavones showed binding energy ranging between -7.44 kcal/mol to -10.1 kcal/mol, when compared with that of the standard compound tamoxifen (-10.0 kcal/mol). Among all the designed compounds, 3-[3-(naphthalen-2-yl) phenyl]-2, 3-dihydro-4Hchroman-4-one (Compound 12) shows more binding energy values (-10.1 kcal/mol). The present findings provide valuable information on the binding process of Isoflavones compounds to the binding site of ERα and reveal the structural requirement needed for binding. [ABSTRACT FROM AUTHOR]

Background: Parasitic worms represent a substantial disease burden in animals and humans worldwide. The control of parasitic roundworms (nematodes) relies heavily on the use of anthelmintic drugs. However, widespread drug resistance in nematodes seriously compromises the effectiveness of many anthelmintics around the world. Thus, there is a need to discover new drugs, with unique modes of action, against parasites. Methods: Here, we synthesised and tested 74 selective estrogen receptor modulators (SERMs) for in vitro-activity on parasitic larvae of Haemonchus contortus (barber's pole worm), one of the most important nematode pathogens of small ruminants (including sheep and goats) and a key representative of one of the largest groups of parasitic nematodes (the Strongylida) of animals. We also studied the morphology of treated and untreated larvae using scanning electron microscopy (SEM), and assessed the agonistic/antagonistic activity of SERMs in a human embryonic kidney cell line using a luciferase reporter assay system. Results: We identified three SERMs (one selenophene and two thiophene-core compounds) with potent inhibitory activities (at 3-25 μM) on the motility and development of parasitic stages of H. contortus. An SEM examination of treated H. contortus revealed considerable damage to the cuticle of fourth- but not exsheathed, third-stage larvae; this damage appeared to be consistent with that observed upon treatment with monepantel but not moxidectin (control compounds). Conclusion: The potency of the three SERMs compared favourably with commercially available anthelmintics, such that they warrant further assessment as nematocides. Future studies could focus on assessing the selectivity of these SERMs to parasites, characterising their target(s) and/or designing analogs that are parasite-specific. [ABSTRACT FROM AUTHOR]

Current guidelines recommend that hormone therapy (HT) in postmenopausal women with a uterus include a progestin to protect against endometrial hyperplasia. However, many concerns relating to HT use appear to be related to the progestin component, including cardiovascular risk, breast stimulation, and irregular vaginal bleeding. Conjugated estrogens (CE) combined with the selective estrogen receptor modulator bazedoxifene (BZA) is a new progestin-free HT option for alleviating estrogen deficiency symptoms in postmenopausal women with a uterus for whom treatment with progestin-containing therapy is not appropriate. Five double-blind, randomized, placebo-controlled, phase 3 studies, known as the Selective estrogens, Menopause, And Response to Therapy (SMART) trials have investigated the efficacy of CE/BZA for relieving vasomotor symptoms (VMS), and effect on bone mass, as well as endometrial and breast safety in postmenopausal women. In a 12-week study, CE 0.45 mg/BZA 20 mg significantly reduced the number and severity of hot flushes compared with placebo at weeks 4 and 12. Unlike estrogen-progestin therapy (EPT), CE 0.45 mg/BZA 20 mg did not increase breast density compared with placebo. In clinical trials up to 2 years, CE/BZA had a favorable tolerability profile, demonstrated by amenorrhea rates similar to placebo. Vascular disorders including venous thromboembolic events (pulmonary embolism, retinal vein thrombosis, deep vein thrombosis, and thrombophlebitis) were rare events, occurring in less than 1 per 1000 patients. CE/BZA was associated with significantly higher incidences of amenorrhea and lower incidences of bleeding compared with CE/medroxyprogesterone acetate in 2 comparative trials. Therefore, CE 0.45 mg/BZA 20 mg provides an effective, well-tolerated, progestin-free alternative to EPT for postmenopausal women with a uterus. [ABSTRACT FROM AUTHOR]

Highlights: [•] Acute 17β-estradiol reduces total infarct volume after transient focal cerebral ischemia in male rats. [•] Bazedoxifene mimics the neuroprotective action of 17β-estradiol. [•] A regional selectivity seems to exist for both 17β-estradiol and bazedoxifene. [•] Bazedoxifene could be a candidate in stroke treatment deserving further research. [Copyright &y& Elsevier]

Highlights: [•] Estradiol regulates reactive astrogliosis and the inflammatory response of astrocytes. [•] Estradiol regulates neuroglobin expression in astrocytes. [•] Estradiol regulates the synthesis of neurotrophic factors in astrocytes. [•] Estradiol controls edema by regulating aquaporin 4 expression in astrocytes. [•] Estradiol controls excitotoxicity by regulating glutamate transport by astrocytes. [ABSTRACT FROM AUTHOR]

Abstract: Fluorinated isoflavanones and bifunctionalized isoflavanones were synthesized through a one-step gold(I)-catalyzed annulation reaction. These compounds were evaluated for their in vitro inhibitory activities against aromatase in a fluorescence-based enzymatic assay. Selected compounds were tested for their anti-proliferative effects on human breast cancer cell line MCF-7. Compounds 6-methoxy-3-(pyridin-3-yl)chroman-4-one (3c) and 6-fluoro-3-(pyridin-3-yl)chroman-4-one (3e) were identified as the most potent aromatase inhibitors with IC50 values of 2.5μM and 0.8μM. Therefore, these compounds have great potential for the development of pharmaceutical agents against breast cancer. [Copyright &y& Elsevier]

Abstract: Tamoxifen is a selective estrogen receptor modulator extensively used on estrogen receptor-positive breast cancer treatment. However, clinical evidences demonstrate the increased incidence of undesirable side effects during chronic therapies, the most life threatening being uterine cancers. Some of these effects are related to tissue-dependent estrogenic actions of tamoxifen, but the exact mechanisms remain poorly understood. We have designed and synthesized a novel fluorescent tamoxifen derivative, FLTX1, and characterized its biological and pharmacological activities. Using confocal microscopy, we demonstrate that FLTX1 colocalizes with estrogen receptor α (ERα). Competition studies showed that FLTX1 binding was totally displaced by unlabeled tamoxifen and partially by estradiol, indicating the existence of non-ER-related triphenylethylene-binding sites. Ligand binding assays showed that FLTX1 exhibits similar affinity for ER than tamoxifen. FLTX1 exhibited antiestrogenic activity comparable to tamoxifen in MCF7 and T47D cells transfected with 3xERE-luciferase reporter. Interestingly, FLTX1 lacked the strong agonistic effect of tamoxifen on ERα-dependent transcriptional activity. Additionally, in vivo assays in mice revealed that unlike tamoxifen, FLTX1 was devoid of estrogenic uterotrophic effects, lacked of hyperplasic and hypertrophic effects, and failed to alter basal proliferating cell nuclear antigen immunoreactivity. In the rat uterine model of estrogenicity/antiestrogenicity, FLTX1 displayed antagonistic activity comparable to tamoxifen at lower doses, and only estrogenic uterotrophy at the highest dose. We conclude that the fluorescent derivative FLTX1 is not only a suitable probe for studies on the molecular pharmacology of tamoxifen, but also a potential therapeutic substitute to tamoxifen, endowed with potent antiestrogenic properties but devoid of uterine estrogenicity. [Copyright &y& Elsevier]

Highlights: [•] Syngonanthus nitens extract and its isolated xanthones demonstrated estrogenic activity. [•] None of the extracts or isolated compounds showed mutagenic activity. [•] Flavones and xanthones could also be used as a new antimutagenic agent. [ABSTRACT FROM AUTHOR]

Abstract: Adjuvant treatment of cancer by chemotherapy is associated with cognitive impairment in some cancer survivors. Breast cancer patients are frequently also receiving endocrine therapy with selective estrogen receptor modulators (SERMs) and/or aromatase inhibitors (AIs) to suppress the growth of estradiol sensitive breast tumors. Estrogens are well-known, however, to target brain areas involved in the regulation of cognitive behavior. In this review clinical and basic preclinical research is reviewed on the actions of estradiol, SERMs and AIs on brain and cognitive functioning to see if endocrine therapy potentially induces cognitive impairment and in that respect may contribute to the detrimental effects of chemotherapy on cognitive performance in breast cancer patients. Although many clinical studies may be underpowered to detect changes in cognitive function, current basic and clinical reports suggest that there is little evidence that AIs may have a lasting detrimental effect on cognitive performance in breast cancer patients. The clinical data on SERMs are not conclusive, but some studies do suggest that tamoxifen administration may form a risk for cognitive functioning particularly in older women. An explanation may come from basic preclinical research which indicates that tamoxifen often acts agonistic in the absence of estradiol but antagonistic in the presence of endogenous estradiol. It could be hypothesized that the negative effects of tamoxifen in older women is related to the so-called window of opportunity for estrogen. Administration of SERMs beyond this so-called window of opportunity may not be effective or might even have detrimental effects similar to estradiol. [Copyright &y& Elsevier]

Highlights: [•] ER-β is silenced in MCF-7 cells with acquired tamoxifen resistance. [•] Treatment with the 5-AZA/TSA re-sensitizes cells to the inhibitory effects of 4-OHT. [•] Transfection with an ER-β expression vector sensitized resistant cells to 4-OHT. [•] ER-β re-expression alone is sufficient to restore sensitivity to tamoxifen. [Copyright &y& Elsevier]

Highlights: [•] A GST-FSH fusion protein was successfully expressed in E. coli. [•] Immunization with GST-FSH antigen can raise high-titer anti-FSH polyclonal sera. [•] Anti-FSH polyclonal sera can neutralize osteoclastogenic effect of FSH in vitro. [•] FSH immunization can prevent bone loss in a rat osteoporosis model. [ABSTRACT FROM AUTHOR]

The identification of the link between breast cancer and estrogens has led to the development of antiestrogens, in particular tamoxifen, to inhibit the activities of estrogen receptors (ERs) in breast cancer cells. The clinical use of tamoxifen has played a major part in decreasing breast cancer mortality over the past 30 years. Though antiestrogenic in the breast, some antiestrogens have estrogen-like actions in other tissues, acting to promote bone density and protect against cardiovascular disease, thus raising the possibility of their use in counteracting the effects of estrogen loss following menopause. Moreover, antiestrogens show efficacy as chemopreventive agents in women at high risk of developing breast cancer. Thus, antiestrogens define an important and well-understood class of cancer drug, which continue to be a mainstay in breast cancer treatment. [ABSTRACT FROM AUTHOR]

Abstract: The development of effective prevention strategies for breast, endometrial and ovarian cancers (CA), based on hormonal responsiveness, is a paramount opportunity in the care of women at risk for these malignancies. Breast CA prevention, utilizing Selective Estrogen Receptor Modulators (SERMs) is a well-established paradigm in the management of high risk women. Aromatase inhibitors (AI) and prophylactic bilateral salpingo-oophorectomy are presently under investigation for that same purpose. Endometrial carcinoma (EC), specifically Type 1, is the most common gynecologic malignancy in the United States. Its positive association with excess estrogen exposure provides significant opportunity for hormonal chemoprevention. Population-based studies have established that oral contraceptives (OC) significantly decrease the incidence of this malignancy. This risk reduction lasts up to 20 years after discontinuation of OCs. The association between elevated BMI and risk of developing EC (due to increased peripheral estrogen exposure) has prompted investigation into the role of weight reduction in EC prevention. The prevention of epithelial ovarian cancer (EOC) is of particular interest given its high mortality rate and the lack of a cost-effective screening program. OC usage significantly diminishes the incidence of EOC, in both the general population, as well as in patients with BRCA 1 or 2 mutations. Risk reduction is greatest with prolonged usage and persists for more than 30 years after OC use, but diminishes over time. Prospective, randomized trials, designed to control for all known variables, are mandatory to fully assess the potential for hormonal chemoprevention in breast, endometrial and ovarian cancers. [Copyright &y& Elsevier]

In this study we investigated the impact of estrogen antagonists and of 16α-OHE1 (an estrogen derivative that binds to and induces transactivation of estrogen receptors) on estrogen metabolism in malignant HepG2 human liver cells featured by high estrogen sulfotransferase (EST); our aim was to clarify the potential correlation of EST and ER. As expected, the HepG2 cells exhibited a very high EST activity, with the majority of estrogen metabolites (over 86%) being detected as sulfates by 24 h. The coincubation of E2 and the antiestrogen tamoxifen induced a weak inhibition of EST activity (from 85.4% to 81.5%), while the coincubation with the pure antagonist ICI-182 and with 16α-OHE1 produced a 50% and 90% decrease of EST, respectively. Interestingly, both selective estrogen receptor modulators (SERMs) TAM and ICI-182, along with the same 16α-OHE1, gave rise respectively to a 2.8%, 3.2%, and 4.6% of de novo 16α-OHE1 formation. The inhibition of EST and the increase of 16α-OHE1 formation were both time- and dose-dependent. Our results suggest that EST activity is tightly associated with ER transactivation and can be regulated by selective estrogen receptor modulators (SERMs), including antiestrogens and 16α-OHE1. In this framework, 16α-OHE1 may have a potential role in human liver carcinogenesis, also through the inhibition of EST and the production of unconjugated, bioavailable estrogens. [ABSTRACT FROM AUTHOR]

Abstract: The estrogen receptors (ERs) are attractive targets in the treatment of breast cancer and the development of receptor-based breast cancer imaging agents for diagnostic use in biomedical imaging technique positron emission tomography (PET). Tetrahydroisoquinoline derivatives are a class of selective estrogen receptor modulators (SERMs) with high binding affinity and specificity exhibiting up to 50 folds for ERα over ERβ. New carbon-11 labeled tetrahydroisoquinoline derivatives, [11C]methyl 1-(2-(4-(2-(4-fluorophenyl)-6-hydroxy-1-methyl-1,2,3,4-tetrahydroisoquinolin-1-yl)phenoxy)ethyl)piperidine-4-carboxylate ([11C]10a) and [11C]methyl 1-(2-(4-(2-(4-chlorophenyl)-6-hydroxy-1-methyl-1,2,3,4-tetrahydroisoquinolin-1-yl)phenoxy)ethyl)piperidine-4-carboxylate ([11C]10b), have been first designed, synthesized and evaluated. The target tracers were prepared by O-[11C]methylation of their corresponding precursors using [11C]CH3OTf and isolated by solid-phase extraction (SPE) purification procedure in 40–60% radiochemical yields, which were decay corrected to the end of bombardment (EOB), based on [11C]CO2. The overall synthesis time was 15–20min from EOB. The radiochemical purity was >99%, and specific activity was in a range of 74–111GBq/μmol at the end of synthesis (EOS). Preliminary findings from in vitro biological assay indicate that the synthesized derivatives displayed similar potencies in the MCF-7 human breast cancer cell line in comparison with 4-hydroxytamoxifen, a well-known potent SERM. These results encourage further in vivo evaluation of carbon-11 labeled tetrahydroisoquinoline derivatives as new potential SERM radioligands for PET imaging of ER expression in breast cancer. [Copyright &y& Elsevier]

Abstract: Sex steroids have potent effects on mood, mental state and cognition. Our previous findings and those of others suggest that these effects may be due at least in part to estradiol actions on central serotonergic mechanisms. Specifically, estradiol-17β in its acute positive feedback mode for gonadotropin release in the female rat induces expression of the genes for the 5-hydroxytryptamine2A receptor (5-HT2AR) and the serotonin transporter (SERT) in the dorsal raphe nucleus (DRN). This is accompanied by an increase in the densities of 5-HT2AR and the SERT in forebrain regions which in the human are concerned with the control of mood, mental state, cognition and emotion. Here we report that raloxifene, a benzothiophene and selective estrogen receptor modulator (SERM), completely blocked estradiol stimulation of brain 5-HT2AR and SERT expression in acutely ovariectomized rats. Raloxifene also blocked the estrogen-induced surge of luteinizing hormone. Treatment of acutely ovariectomized rats with raloxifene alone increased the density of SERT sites in the mid-frontal cortex and decreased the density of 5-HT2AR in the posterior olfactory tubercle. The inhibitory effects of raloxifene on acute estrogen-induction of central serotonergic mechanisms were similar to those of tamoxifen even though there are major differences between the two SERMs in their affinity for the two estrogen receptor subtypes and their actions on the uterus. These findings provide robust evidence that estradiol induction of the 5-HT2AR and the SERT in brain is mediated by nuclear estrogen receptors. Our data may provide the basis for obtaining a better understanding of the effects of sex steroids on mood and mental state in the human and the possible rational development of congeners of sex steroids for the treatment of mental disorders. [Copyright &y& Elsevier]

Coronary artery disease (CAD) is the main contributor of mortality among postmenopausal women. Menopause-associated estrogen deficiency has both metabolic and vascular consequences that increase the risk for CAD. Hormone therapy (HT) has been reported to have a beneficial effect on metabolic and vascular factors influencing the incidence of CAD. Although observational studies have reported that HT reduces significantly the risk for CAD, randomized clinical trials (WHI, HERS, ERA) have questioned the efficacy of HT in primary and secondary CAD prevention despite confirming the lipid-lowering effect of HT. In the aftermath of the WHI, increased interest has been given to the action of selective estrogen receptor modulators (SERMs) and their effect on the cardiovascular system. The chemical structure of SERMs, either triphenylethilyn (tamoxifen) or benzothiophene (raloxifene) derivatives, differs from that of estrogens. SERMs are nonsteroidal molecules that bind, with high affinity, to the ER. SERMs induce conformational changes to the ligand-binding domain of the ER that modulate the ability of the ER to interact with coregulator proteins. The relative balance of coregulators within a cell determines the transcriptional activity of the receptor–ligand complex. SERMs therefore may express an estrogen-agonist or estrogen-antagonist effect depending on the tissue targeted. SERMs express variable effects on the metabolic and vascular factors influencing the incidence of CAD. SERMs have been reported to modulate favorably the lipid–lipoprotein profile. Toremifene expresses the most beneficial effect followed by tamoxifene and raloxifene, while ospexifene and HMR-3339 have the least effect and may even increase triglycerides. Raloxifene and tamoxifene decrease serum homocysteine levels and C-reactive proteins (CRP), which are both markers of CAD risk. Raloxifene has been reported to increase the nitric oxide (NO)–endothelin (ET)-1 ratio and, thus, contribute to proper endothelial function and vasodilation. Toremifene has no effect on the NO–ET-1 ratio. Finally, raloxifene decreases the vascular cell adhesion molecules and the inflammatory cytokines TNF-α and IL-6. Of the SERMs, raloxifene has had the most extensive evaluation regarding the effect on the vascular wall of endothelium. Although not confirmed by large clinical trials, raloxifene has been reported to have an effect on the cohesion of the intercellular junction (VE-cadherin) and the synthesis—degradation of extracellular matrix (MMP-2). The Multiple Outcomes Raloxifene Evaluation (MORE) study has reported that raloxifene may have a cardioprotective effect when administered to postmenopausal women at high risk for CAD disease. [ABSTRACT FROM AUTHOR]

We examined in vivo effects of selective estrogen receptor modulators (SERMs) 4-OH-tamoxifen (Tam), GW 5638 (GW) and EM-800 (EM) on myometrial gene expression. The uteri of ovariectomized ewes were infused with 10−7 M of one SERM via indwelling catheters for 24 h preceding hysterectomy. Half of the ewes in each SERM group received an intramuscular injection of 50 μg 17β-estradiol (E2) 18 h prior to hysterectomy. Northern blot analysis and in situ hybridization demonstrated that E2 increased estrogen receptor (ER), progesterone receptor (PR) and cyclophilin (CYC) gene expression in the cells of both inner layer of myometrium (IM) and outer layer of myometrium (OM) as well as glyceraldehyde 3-phosphate dehydrogenase (GAPDH) gene expression in OM. Tam also increased ER mRNA levels in OM. EM appeared to increase ER gene expression, but antagonized E2’s up-regulation of PR and CYC gene expression in both IM and OM. Tam and GW also antagonized E2 up-regulation of PR gene expression in OM but not IM. No SERM affected GAPDH gene expression with or without E2. Immunohistochemistry indicated that E2 increased nuclear ER and PR protein levels in both IM and OM. EM was unique in up-regulating ER protein levels, opposite to its effects in endometrial cells. All SERMs tested antagonized this increase in PR immunostaining preferentially in OM compared to the IM layer. These results illustrate gene and cell layer-specific effects of SERMs in sheep myometrium. [Copyright &y& Elsevier]

Ovarian hormone deficiency is a major risk factor for osteoporosis. Current therapies emphasize the use of antiresorptive agents, such as estrogen, calcitonin, and bisphosphonates. These therapies are associated with certain risks and side effects making compliance a major obstacle. Recent findings suggest that a class of synthetic and naturally occurring compounds, selective estrogen receptor modulators, e.g. raloxifene and soy isoflavones can offer attractive alternatives. Evidence for bone-sparing effects of isoflavones relies mainly on animal findings supported by a limited number of human studies. These observations suggest that isoflavones exert their effects on bone by stimulating bone formation and at the same time suppressing bone resorption. However, the precise osteoprotective mechanism of isoflavones remains uncertain and awaiting further clarification. From a clinical point of view, larger and longer duration studies are warranted to enable us to draw clear conclusions in regards to the role of isoflavones on bone. [Copyright &y& Elsevier]

In spite of the fact that women spend 1/3 of their lives in postmenopause, the search for appropriate therapies able to counteract the derangements associated with the menopause still represents a sort of sought after the "Holy Grail."Nowadays, the combination of estrogens and selective estrogen receptor modulators (SERMs), a class of compounds with a mixed agonist/antagonistic activity on the estrogen receptor (ER) in various tissues, represents the most promising approach to improve postmenopausal women's health, by preserving the benefits while avoiding the side effects of estrogen-based therapy.Given their complex mechanisms of action, the evaluation of SERM activity in combination with conjugated estrogens (CE) requires a multifactorial analysis that takes into account the multifaceted and dynamic effects of these compounds in target tissues, even in relation to the physiological/pathological status.To accomplish such a goal, we took advantage of the ERE-Luc model, a reporter mouse that allows the monitoring of ER transcriptional activity in a spatio-temporal dimension. Cluster analyses performed on in vivo/ex vivo bioluminescence (BLI) data and ex vivo luciferase activity enabled to sustain the combination of CE plus bazedoxifene (TSEC, tissue-selective estrogen complex) as a valuable option for the pharmacological treatment of the postmenopause., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Testosterone deficiency is defined as a total testosterone level <300 ng/dL confirmed on two early morning lab draws. Testosterone therapy has historically been offered to men with symptomatic testosterone deficiency in the form of injections, gels, or pellets. However, these treatments are invasive or have undesirable effects including the risk of drug transference. Additionally, testosterone therapy has been associated with increases in hematocrit and controversy remains regarding the risk of cardiovascular and thromboembolic events while on testosterone therapy. As such, much interest has recently been focused on alternative treatment options for testosterone deficiency in the form of orally-administered medications with more favorable side effect profiles. Lifestyle modifications and varicocelectomy have been shown to raise endogenous testosterone production. Similarly, SERMs and aromatase inhibitors (AIs) have been shown to raise testosterone levels safely and effectively. Human chorionic gonadotropin (hCG) remains the only FDA-approved non-testosterone treatment option for testosterone deficiency in men. However, this medication is expensive and requires patient-administered injections. Over the counter herbal supplements and designer steroids remain available though they are poorly studied and are associated with the potential for abuse as well as increased hepatic and cardiovascular risks. This review aims to discuss the existing treatment alternatives to traditional testosterone therapy, including efficacy, safety, and side effects of these options. The authors suggest that the SERM clomiphene citrate (CC) holds the greatest promise as a non-testosterone treatment option for testosterone deficiency., Competing Interests: Conflicts of Interest: The focused issue “Contemporary Issues and Controversies in Men’s Health” was commissioned by the editorial office without any funding or sponsorship. The authors have no conflicts of interest to declare., (2020 Translational Andrology and Urology. All rights reserved.)

• A scaffold of 2-arylbenzofuran-containing compounds are ligands for ERα. • 10-Dehydrooxyglycyuralin E shows partial agonistic activity for ERα in the reporter assay. • 10-Dehydrooxyglycyuralin E shows anti-estrogenic/proliferative activity in breast cancer cells. • 10-Dehydrooxyglycyuralin E is a candidate for Selective Estrogen Receptor Modulators (SERMs). Selective estrogen receptor modulators (SERMs) act as either agonist or antagonist of estrogen receptor (ER) in a tissue selective manner and have been used in several diseases such as breast cancer, postmenopausal syndrome, osteoporosis, and cardiovascular diseases. However, current SERMs may also increase the risk of serious side effects and trigger drug resistance. Herein, a screening program, that was designed to search for novel SERMs, resulted in the identification of a series of 2-arylbenzofuran-containing compounds that are ligands for ERα, when applying the Gaussia -luciferase reporter assay. One of these compounds, 10-dehydrooxyglycyuralin E (T9) was chemically synthesized. T9 showed anti-estrogenic/proliferative activity in ERα-positive breast cancer cells. Pretreatment of T9 prevented the mRNA expression of GREB1 , which is an estrogen response gene. Furthermore, by an in silico docking simulation study we demonstrated that T9 showed interactions directly to ERα. Taken together, these results demonstrated that T9 is a candidate of SERMs and a useful seed compound for the foundation of the selective activity of SERMs. [ABSTRACT FROM AUTHOR]

Background: This population-based cohort study was to compare the risks of incident cancer in osteoporosis patients who used bisphosphonates, calcitonin or selective estrogen receptor modulators (SERMs)., Methods: We identified 9995 patients who were diagnosed with osteoporosis and prescribed osteoporosis drugs (bisphosphonate (n = 4675), calcitonin (n = 3993) and SERMs (n = 1327)) between 1 January 2000 and 31 December 2006 in Taiwan's National Health Insurance Research Database. Date of first prescription of osteoporosis drugs was assigned as the index date. The outcome measurement was incident cancer, defined by a first-ever inpatient visit with a primary diagnosis of cancer. All patients were followed until the occurrence of cancer. For those who did not develop cancer, we censored them at 1 year after their last prescription of osteoporosis drugs. Cox proportional hazard models were used to examine the association between risk of cancer and use of calcitonin, bisphosphonates or SERMs., Results: The incidence rate of cancer was 68.8, 34.0 and 29.6 per 1000 person years in the calcitonin, SERMs and bisphosphonate cohorts, respectively. Compared with bisphosphonate users, calcitonin users were associated with an increased risk of cancer (adjusted hazard ratio (HR) 2.11, 95% confidence interval (CI) 2.01-2.21, P < 0.001). SERM users were associated with an increased risk of cancer (adjusted HR 1.20, 95% CI 1.13-1.28, P < 0.001)., Conclusion: Our findings suggest that calcitonin is associated with an increased risk of cancer than bisphosphonate, supporting the recent warning issued by the European Medicines Agency and US Food and Drug Administration. SERMs is found to be associated with an increased risk of cancer than bisphosphonate., (© The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Selective estrogen receptor modulators (SERMs) are a class of compounds that act differentially on the estrogen receptor (ER) in various tissues with a mixed agonist/antagonistic activity (agonistic in some tissues while antagonist in others). This peculiarity represents a challenge for developing new hormone replacement therapies (HRTs) and highlights the need of new tools to evaluate the specific effects of a given SERM in different organs/tissues of an entire organism and with time. Reporter mice represent invaluable tools in pharmacology to analyze specific signaling in physiological conditions and monitor the effects of drugs acting on these signals in a spatio-temporal dimension. Here, we describe an in vivo protocol to examine the effects of different SERMs on estrogen receptor activity by using the ERE-Luc reporter model, a mouse that reports ER transcriptional activity.

The formation of quinone methides (QMs) from either direct 2-electron oxidation of 2- or 4-alkylphenols, isomerization of o -quinones, or elimination of a good leaving group could explain the cytotoxic/cytoprotective effects of several drugs, natural products, as well as endogenous compounds. For example, the antiretroviral drug nevirapine and the antidiabetic agent troglitazone both induce idiosyncratic hepatotoxicity through mechanisms involving quinone methide formation. The anesthetic phencyclidine induces psychological side effects potentially through quinone methide mediated covalent modification of crucial macromolecules in the brain. Selective estrogen receptor modulators (SERMs) such as tamoxifen, toremifene, and raloxifene are metabolized to quinone methides which could potentially contribute to endometrial carcinogenic properties and/or induce detoxification enzymes and enhance the chemopreventive effects of these SERMs. Endogenous estrogens and/or estrogens present in estrogen replacement formulations are also metabolized to catechols and further oxidized to o -quinones which can isomerize to quinone methides. Both estrogen quinoids could cause DNA damage which could enhance hormone dependent cancer risk. Natural products such as the food and flavor agent eugenol can be directly oxidized to a quinone methide which may explain the toxic effects of this natural compound. Oral toxicities associated with chewing areca quid could be the result of exposure to hydroxychavicol through initial oxidation to an o -quinone which isomerizes to a p -quinone methide. Similar o -quinone to p -quinone methide isomerization reactions have been reported for the ubiquitous flavonoid quercetin which needs to be taken into consideration when evaluating risk-benefit assessments of these natural products. The resulting reaction of these quinone methides with proteins, DNA, and/or resulting modulation of gene expression may explain the toxic and/or beneficial effects of the parent compounds.

Risk factors allow us to define women who are at increased lifetime risk for breast cancer, and the most important factor is age. Benign breast disease increases risk, and the most important histologies are atypical lobular or ductal hyperplasia and lobular carcinoma in situ. Family history of breast cancer among first-degree relatives (mother, sisters, daughters) also increases risk. Quantitative measures of risk give accurate predictions of breast cancer incidence for groups of women but not for individual subjects. Multiple published, randomized controlled trials, which employed selective estrogen receptor (ER) modulators (SERMs), have demonstrated consistent reductions of 35% or greater in the risk of ER-positive invasive and noninvasive breast cancer in postmenopausal women. Professional organizations in the US now recommend the use of SERMs to reduce the risk of breast cancer in high-risk, postmenopausal women. Raloxifene and tamoxifen reduce the risk of ER-positive invasive breast cancer with equal efficacy, but raloxifene is associated with a lower risk of thromboembolic disease, benign uterine conditions, and cataracts than tamoxifen in postmenopausal women. No evidence exists establishing whether a reduction in breast cancer risk from either agent translates into reduced breast cancer mortality. Overall quality of life is similar with raloxifene or tamoxifen, but the incidence of dyspareunia, weight gain, and musculoskeletal complaints is higher with raloxifene use, whereas vasomotor symptoms, bladder incontinence, gynecologic symptoms, and leg cramps were higher with tamoxifen use.