PRODUCTION AND APPLICATION OF MOUSE ANTISERUM TO HUMAN ESTROGEN RECEPTORS

A polyclonal antibody to peptide containign 15 amino acids and corresponding to reion-D of human estrogen receptors(hERD)was obtained in mice by immunization with the coupler of peptide and KLH. Usuig this antiserum,the ER stathe of paraffin-embeded sections of 95 human breast carcinomas were studied. The corresponding rate for determination of ER status between immunohistochemical staining(IHC)and dextran coated charcoal(DCC)assay was 89. 5%. The concordance for semiquantitative grades was 69.3%. In addition, in situ hybridization(ISH)of 15 frozen sections of same sample using digoxigenin labeled dUTP to identify the expreesion of ER mRNA for confirming the 1HC also be used. This technique revealed more specific,sensitive and convenient than DCC.The results of ISH were fully consistent with IHC(100%). Above results show that the mouse antsierum hERD obtained in this study is specific and sensitive for IHC assay of ER and IHC is a valuable adjunct and/or alternative to the biochemical method for determination of the ER status of breast cancer.

Unveiling the effect of estrogen receptors in alcoholic liver disease:A novel outlook

Alcoholic liver disease(ALD)has a multifaceted development,progressing from alcoholic steatosis to alcoholic hepatitis and ultimately to alcoholic cirrhosis,irreversible liver damage that can even result in hepatocellular carcinoma.The prevalence of ALD is increasing globally,particularly among middle-aged adults.Gender-based studies have revealed that ALD affects more men;however,disease progression differs between men and women.Despite this,the molecular understanding of alcohol-induced liver injury among genders and its association with changes in sex hormone metabolism,particularly with estrogen and estrogen receptors(ERs)in ALD,remains poor.This review focuses on experimental and human studies describing alcohol and its association with estrogen metabolism and signaling via ERs.Chronic alcohol consumption affects the immune response,and whether estrogen has any contributory effect remains inadequately studied.This review also discusses various therapeutic approaches currently in use and future approaches that can affect the response or progression via estrogen signaling.The role of gender on alcohol consumption and its association with steroid hormones must be elucidated for a better understanding of the pathogenesis of ALD,the development of effective therapeutic approaches,and better disease management in both men and women,as ALD remains a major public health concern.

Regulation of estrogen receptors α and β in human breast carcinoma by exogenous leptin in nude mouse xenograft model

Background It is essential to clarify the interactions of hormones during the progression of human breast cancer. This study examined the effects of exogenous human leptin on estrogen receptor （ER） α and β in human breast tumor tissue in a nude mouse xenograft model. Methods We created nude mice xenografts of MCF-7 human breast cancer cells, and randomly divided them into an experimental group and a control group. The mice in experimental group were injected subcutaneously around tumors with human leptin, while the control group were injected with the same dose of normal saline. A real-time RT-PCR assay was developed to quantify the mRNA of ERα, β in the tumor tissues. Western blotting analyses were used to assess the relative quantities of the ERα , β proteins. Results Leptin-treated xenografted nude mice were successfully established. The amount of ERa mRNA was significantly higher in the leptin group than in the control group （P 〈0.01）, while the amount of ERβ mRNA was significantly lower in the leptin group than in the control group （P 〈0.01）. Western blotting analyses revealed that the ERa protein level was significantly higher in the leptin group than in the control group （P 〈0.01）, while the ERβ protein level was significantly lower in the leptin group than in the control group （P 〈0.01）. Conclusions Nude mouse xenograft model can be safely and serviceably treated with human leptin by subcutaneous injections around tumor. ERα, β were both targets of leptin in breast cancer. Leptin can up-regulate the expression of ERa and down-regulate the expression of the ERβ in human breast tumor.

Er-xian ameliorates myocardial ischemia-reperfusion injury in rats through RISK pathway involving estrogen receptors

Curculigo orchioides(CUR)and Epimedium(EPI)are traditional Chinese medicines with estrogen-like biological activity,called Xianmao and Xianlingpi(Er-xian)in Chinese.However,whether Er-xian exerts protective effects on myocardial ischemia-reperfusion injury(MIRI)is unknown.This study aimed to investigate the cardioprotective effects of Er-xian preconditioning against MIRI and the underlying mechanisms.CUR or EPI was administered intragastrically to aged female rats as a monotherapy or combination therapy.2 weeks later,a rat MIRI model was established.Myocardial infarction size,myocardial morphology,cTnT,cell apoptosis rate,intracellular calcium concentration,mitochondrial permeability transition pore(MPTP)opening and reperfusion injury salvage kinase(RISK)signaling pathway molecules were observed after the surgery.To evaluate the mechanisms of Er-xian,estrogen receptors antagonists ICI 182780 and G15 were used.In this study,Er-xian notably alleviated myocardial tissue damage,maintained mitochondrial morphology,reduced infarct size and cardiac markers,and increased sera levels of E2.Moreover,Er-xian inhibited calcium overload and mPTP opening,and decreased cardiomyocyte apoptosis.We found that the dual therapy of CUR and EPI elicited more noticeable results than CUR or EPI monotherapy.The significant protective effects of Er-xian on ischemia-reperfusion myocardium were attributed to the up-regulation of AKT,ERK1/2 and GSK-3βphosphorylation levels.The cardioprotective effects of Er-xian were significantly reduced after estrogen receptor blockade,especially GPER30.These results indicate that Er-xian attenuates MIRI through RISK signaling pathway and estrogen receptors are the critical mediators.

Expression of Progesterone and Estrogen Receptors in Human Renal Cell Carcinoma

Progesterone receptor(PR) and estrogen receptor(ER) were investigated in 29 specimens of renal cell carcinoma (RCC) and its autologous kidneys, 12 samples of control kidnerys with high sensitive and specific enzymelabelled histochemical techniques. The positive expression rates of PR in RCC, its autologous kidneys and control kidneys were 31.0%, 82.8% and 83.3% respectively, while the positive expression rates of ER of those tissues were 58.6%, 79.3% and 83.3%, respectively. It showed that the positive rate and the value of PR and ER in RCC were significantly less than those determined in the autologous kidneys and normal tissues(P<0.05) and no significant differences of PR and ER were found between autologous and normal kidneys(P>0.05). The level and positive rate of PR in stage Ⅰ were higher than those in stage Ⅱ to Ⅳ of RCC tissues (P<0.05). There was no relationship between the status of PR, ER and patient sex(P>0.05). Expression of PR in RCC had correlation to Robson stage closely. The positive rate of PR may be treated as a prognostic factor because it decreased as the stage rose. Our result provided an experimental basis for the application of hormonal therapy in RCC and emphasized that patients who may be benefited from hormonal therapy must have sufficient hormone receptors.

Effects of estrogen and tibolone on bladder histology and estrogen receptors in rats

Background Estrogen deficiency causes atrophic changes within the urogenital tract, and is associated with urinary symptoms. The purpose of this study was to investigate the effects of estrogen and tibolone on bladder histology, and the changes of estrogen receptor a and β （ERα and β） protein expression in the detrusor muscle.Methods Forty female rats were separated into four groups of ten each. They received a sham operation （Sham）, ovariectomy （Ovx）, ovariectomy plus estrogen replacement （Ovx＋E）, or ovariectomy plus tibolone treatment （Ovx＋T）. After 12 weeks each rat was anesthetized and the bladders were removed. The bladders＇ ultra structure, collagen fiber （CF） to smooth muscle（SM） ratio and ER subtypes were studied. Statistical analyses were performed using the one-way analysis of variance test. Results Ovx resulted in significant degeneration in bladder ultra structure; however, estrogen and tibolone reversed those changes. Ovx increased the CF/SM ratio, estrogen and tibolone resulted in an increase. Two estrogen receptors （ERs） were expressed in the bladder detrusor, with ERβ the main subtype. Ovx resulted in up-regulation of ERα and down-regulation of ERβ. With estrogen and tibolone treatment, ERβ showed a significant increase but ERα showed no significant difference compared with Ovx. Conclusions Estrogen deficiency deteriorates bladder ultra structure and histology. Supplementary estrogen can improve bladder function which may be due to inhibition of collagen hyperplasia and increased SM density. ERβ has an important role in mediating estrogen function in the bladder. Tibolone has a mild estrogenic action and has an effect on bladder function and structure to some degree.

Effects of Transdermal Estrogen Therapy on Expressions of Estrogen Receptors and T-lymphocyte Apoptosis in Surgically Menopausal Women

Studies have demonstrated estrogen replacement therapy can improve the life quality of surgically menopausal women. However, the mechanisms in this process remain poorly defined. Here we show the effect of transdermal estrogen therapy on expressions of estrogen receptors and T-lymphocyte apoptosis in surgically postmenopausal women. Fifteen surgically menopausal women, 15 naturally menopausal women and 15 young women were chosen in our studies. Peripheral vein blood was collected and serum E2 and FSH levels were assessed using ACCESS. T-lymphocyte apoptosis and the expressions of Fas, FasL and ER subtypes α and β were determined. The serum E2 levels of surgically menopausal woman were significantly higher, and the ＂Improved Kupperman Index＂ and the scores of ＂Menopause Specific Quality of Life Questionnaire＂ in surgically menopausal women were significantly low after ERT. The rates of T-lymphocyte apoptosis and FasL expression in surgically menopausal women were decreased after ERT, but the difference was not significant. The expressions of ERa and ERβ in two menopausal groups were significantly lower than those of the young group. They were both significantly up-regulated after 3 months of ERT. Transdermal ERT could significantly upregulate the serum E2 level, could improve menopausal symptoms and life quality of surgically menopausal women and upregulate ERa and ERβ expressions on T lymphocytes, especially ERp. Thus, the low dose of transdermal ERT may have a protective effect on menopausal women＇s immune function and aging.

Effects of Mifepristone Compound on the Receptors of Estrogen and Progesterone in Early Pregnancy Deciduas

To examine the effect of mifepristone compound (mifepristone + anor- drin) on estrogen receptor (ER) and progesterone receptor (PR) in early pregnancy decidua. Materials & Methods A Controlled study was carried out among 60 normal early pregnant volunteers (≤49d) in the department of obstetric and gynecology of Peking Union Medical Hospital. The concentrations of ER and PR were measured by radio- ligand and were compared with the control subjects after oral administration of mifepristone or mifepristone compound in different doses. Results The concentration of PR decreased while that of ER increased significantly in the decidua from all subjects administrated with mifepristone compound. We also found the concentration of EcR in Group 5 (mifepristone 30 mg + AF-53 5 mg) was the highest among 6 groups. The compound may be in favor of estrogen's action on endometrium. Conclusion The results indicate that mifepristone compound with AF- 53 has a coordi- nated function and can change the proportion of PR and ER. Hence, it can facilitate abortion. The compound dose of mifepristone 30 mg + AF-53 5mg is in favor of the endometrium recovering.

Clinical Significance of Estrogen and Progesterone Receptors Assays in Pancreatic Carcinoma

Cyochemical methods for demonstrating estrogen receptor (ER) and progesterone receptor (PgR)within pancreas-cancer cells showed positive reation of ER or/and PgR in 4 out of 8 pancreatic carcinomas.This result suggested that sex hormone might be closely linked to pancreatic cancer.Pancreatic carcinoma could be considered a hormoneresponsive-neoplasm. The hormone migh be a cause influencing the growth of pancreatic carcinoma in association with receptors described. Endocrine therapy would be a treatment of choice for pancreatic carcinoma.

Estrogen Receptor α and β Expressions in Hypothalamus-pituitary-ovary Axis in Rats Exposed Lactationally to Soy Isoflavones and Bisphenol A

Objectives This paper aims to investigate the uterotrophic activities of lactational exposure to combination of soy isoflavones （SIF） and bisphenol A （BPA） and to examine estrogen receptor α （ERα） and estrogen receptor β （ERβ） expressions in hypothalamus-pituitary-ovary axis and uterus.Methods Maternal rats that were breeding about 8 litters were randomly divided into four groups with seven dams in each group.Dams in different treatment groups received corn oil （control）,150 mg/kg BW of SIF,150 mg/kg BW of BPA or combination of 150 mg/kg BW of SIF and 150 mg/kg BW of BPA,respectively,from postnatal day 5 to 11 （PND5-11） by gavage.On PND12 and PND70,10 female litters were killed and hypothalamus,pituitary,ovary and uterus were collected.ERα and ERβ expressions in these organs were detected with Western blotting assay.And vaginal opening time and estrus cycle were examined in animals fed for PND70.Results On PND12,the relative uterine weight of rats treated with ISF or BPA or their combination was significantly higher than that of untreated rats （P〈0.05）.But the relative uterine weight of rats in the co-exposure group was slightly lower than that in the group only exposed to SIF or BPA.On PND 70,however,the relative uterine weight in each treatment group was not statistically different from that in the control group （P〈0.05）.Vaginal opening time and estrus cycle in groups treated with SIF or BPA or their combination were similar to those in the control group （P〈0.05）.Exposure to SIF or BPA or their combination could up-regulate or down-regulate ERα and ERβ expressions in hypothalamus,pituitary,ovary and uterus on PND12 and PND70.These regulation patterns for ERα and ERβ were different in different organs at different time points.Conclusion Lactational exposure to ISF or BPA or their combination could induce uterotrophic responses in neonate rats,which disappeared in later life.But these data fail to suggest a possibility for synergic actions between SIF and BPA.It was also demonstrated that the uterotrophic effects of SIF and BPA exposure might,at least,involve modification of ERα or ERβ expressions in the hypothalamus-pituitary-ovary axis.

Age-related decrease in aromatase and estrogen receptor （ERα and ERβ） expression in rat testes： protective effect of low caloric diets

Aim： To examine the effects on rat aging of caloric restriction （CR1） and undernutrition （CR2） on the body and on testicular weights, on two enzymatic antioxidants （superoxide dismutase and catalase）, on lipid peroxidation and on the expression of testicular aromatase and estrogen receptors （ER）. Methods： CR was initiated in 1-month-old rats and carried on until the age of 18 months. Results： In control and CR2 rats an age-related decrease of the aromatase and of ER （α and β） gene expression was observed; in parallel a diminution of testicular weights, and of the total number and motility of epididymal spermatozo was recorded. In addition, aging in control and CR2 rats was accompartied by a significant decrease in testicular superoxide dismutase, catalase activities, and an increase in lipid peroxidation level （thiobarbituric acid reactive substance）, associated with alterations of spermatogenesis. Conversely, caloric restriction-treatment exerted a protective effect and all the parameters were less affected by aging. Conclusion： These results indicate that during aging, a low caloric diet （not undernutrition） is beneficial for spermatogenesis and likely improves the protection of the cells via an increase of the cellular antioxidant defense system in which aromatase/ ER could play a role. （Asian J Andro12008 Mar; 10： 177-187）

Estrogens and the regulation of glucose metabolism

The main estrogens:estradiol,estrone,and their acyl-esters have been studied essentially related to their classical estrogenic and pharmacologic functions.However,their main effect in the body is probably the sustained control of core energy metabolism.Estrogen nuclear and membrane receptors show an extraordinary flexibility in the modulation of metabolic responses,and largely explain gender and age differences in energy metabolism:part of these mechanisms is already sufficiently known to justify both.With regard to energy,the estrogen molecular species act essentially through four key functions:(1)Facilitation of insulin secretion and control of glucose availability;(2)Modulation of energy partition,favoring the use of lipid as the main energy substrate when more available than carbohydrates;(3)Functional protection through antioxidant mechanisms;and(4)Central effects(largely through neural modulation)on whole body energy management.Analyzing the different actions of estrone,estradiol and their acyl esters,a tentative classification based on structure/effects has been postulated.Either separately or as a group,estrogens provide a comprehensive explanation that not all their quite diverse actions are related solely to specific molecules.As a group,they constitute a powerful synergic action complex.In consequence,estrogens may be considered wardens of energy homeostasis.

Clinicopathological Features and Long-Term Prognostic Role of Human Epidermal Growth Factor Receptor-2 Low Expression in Chinese Patients with Early Breast Cancer:A Single-Institution Study

Objective This study aimed to comprehensively analyze and compare the clinicopathological features and prognosis of Chinese patients with human epidermal growth factor receptor 2(HER2)-low early breast cancer(BC)and HER2-IHC0 BC.Methods Patients diagnosed with HER2-negative BC(N=999)at our institution between January2011 and December 2015 formed our study population.Clinicopathological characteristics,association between estrogen receptor(ER)expression and HER2-low,and evolution of HER2 immunohistochemical(IHC)score were assessed.Kaplan-Meier method and log-rank test were used to compare the long-term survival outcomes(5-year follow-up)between the HER2-IHC0 and HER2-low groups.Results HER2-low BC group tended to demonstrate high expression of ER and more progesterone receptor(PgR)positivity than HER2-IHC0 BC group(P<0.001).The rate of HER2-low status increased with increasing ER expression levels(Mantel-Haenszelχ^(2)test,P<0.001,Pearson’s R=0.159,P<0.001).Survival analysis revealed a significantly longer overall survival(OS)in HER2-low BC group than in HER2-IHC0 group(P=0.007)in the whole cohort and the hormone receptor(HR)-negative group.There were no significant differences between the two groups in terms of disease-free survival(DFS).The discordance rate of HER2 IHC scores between primary and metastatic sites was 36.84%.Conclusion HER2-low BC may not be regarded as a unique BC group in this population-based study due to similar clinicopathological features and prognostic roles.

17β-Estradiol Regulates Cultured Immature Boar Sertoli Cell Proliferation via the cAMP-ERK1/2 Pathway and the Estrogen Receptor β

Estrogen plays an important role in regulating Sertoli cell number in the testis. The objective of the study was to identify whether 17β-estradiol affected the proliferation of cultured, immature boar Sertoli cells via the estrogen receptor β （ERβ） and the cAMP-extracellular signal-regulated kinase （ERK1/2） pathway. Low levels （10-10-10-8 mol L-1） of 17β-estradiol increased cell number, but high levels （10-7-10-6 mol L-1） decreased it （P〈0.05）. Sertoli cell number began to recover for an additional 24 h in the medium without 17β-estradiol （10-6 mol L-l） （P〉0.05）. The effects of 17β-estradiol （10-9 mol L-1） peaked at the first 24 h （P〈0.05）. 17β-estradiol activated ERK1/2 from 5 min to 24 h, but the activiy of ERK1/2 began to decrease after 4 h. Both PD98059 and U0126, two ERK inhibitors, blocked cell division （P〈0.05）. 17β-estradiol （10-10-10-6 mol L-1） dose-dependently increased cAMP production （P 〈 0.05）, and both 17β-estradiol （10-9 mol L-1） and forskolin, which increases cAMP levels, induced cell proliferation and activated ERK1/2 （P〈 0.05）. Rp-cAMP, an antagonist of cAMP, blocked this 17β-estradiol activity （P〈 0.05）. Two estrogen receptor antagonists, ICI 182780 and ERβ antagonist （ERβAnt）, reduced Sertoli cell number, cAMP production and ERK1/2 activation （P〈 0.05）, but ERaAnt did not （P〉 0.05）. Therefore, 17β- estradiol mainly promotes pig Sertoli cell proliferation via ERβ to induce cAMP production and ERK activation to promote cell proliferation.

The Relationship of CyclinD1 and Estrogen Receptor Expression in the Process of Proliferation and Metastasis in Breast Neoplasm

The role of CyclinD1 and estrogen receptor (ER) in the process of proliferation and metastasis of breast neoplasm and their relationship were studied. The expression levels of CyclinD1 and ER in the tissue samples were detected by using flow cytometry and L SAB immunohistochemistry staining, respectively. The results showed that CyclinD1 and ER expression levels in breast cancer were significantly higher than in benign breast neoplasm (P<0.05). The CyclinD1 expression levels in stage I was much lower than in stages Ⅱ, Ⅲ, Ⅳ (P<0.05). The positive rate of ER was not related with tumor size, lymph node metastasis and TNM stage (P>0.05), but the CyclinD1 expression level in ER (+) group was significantly higher than in ER (-) group (P<0.05). It was concluded that CyclinD1 expression level might be obviously related with the proliferation and metastasis of breast neoplasm and ER.

Combined treatment with valproic acid and estrogen has neuroprotective effects in ovariectomized mice with Alzheimer’s disease

Postmenopausal women with Alzheimer’s disease exhibit dramatically reduced sensitivity to estrogen replacement therapy,which is though to be related to an estrogen receptor(ER)α/ERβratio imbalance arising from a significantly decreased level of ERs of the brain.The aim of our study was to investigate whether valproic acid(VPA)can enhance the beneficial effects of estrogen on cognitive function through restoration of ERαand ERβexpression in the brain.We removed the ovaries of female APP/PS1 mice to simulate the low estrogen levels present in postmenopausal women and then administered VPA(30 mg/kg,intraperitoneal injection,once daily),17β-estradiol(E2)(2.4μg,intraperitoneal injection,once daily),liquiritigenin(LG)(50μg/kg,intragastric infusion,once daily),VPA+E2,or VPA+LG for 4 successive weeks.Compared with treatment with a single drug,treatment with VPA+E2 or VPA+LG significantly increased the level of glycogen synthase kinase 3β,increased the expression of estrogen receptorα,reduced the expression of small ubiquitin-like modifiers,and increased the level of estrogen receptorβ.This resulted in enhanced sensitivity to estrogen therapy,reduced amyloidβaggregation,reduced abnormal phosphorylation of the tau protein,reduced neuronal loss,increased dendritic spine and postsynaptic density,and significantly alleviated memory loss and learning impairment in Alzheimer’s disease.This study was approved by the Chongqing Medical University Animal Protection and Ethics Committee,China on March 6,2013.

T29C genotype polymorphism of estrogen receptor alpha is associated with initial response to interferon-alpha therapy in chronic hepatitis B patients

BACKGROUND: Virological clearance, delayed progression to cirrhosis or liver cancer, and increased survival are the long-term goals of antiviral therapy in chronic hepatitis B patients. Identification of host factors correlated with therapeutic response may contribute greatly to individual treatment. This study aimed at investigating whether T29C genotype polymorphism of estrogen receptor alpha (ESR1) is associated with the initial response to interferon-alpha (IFN-alpha) therapy in chronic hepatitis B patients. METHODS: The initial responses of 100 patients to IFN-alpha therapy were evaluated and compared by classifying them into three groups according to T29C genotype polymorphism of ESR1: T/T, TIC, and C/C genotype groups. Polymerase chain reaction-restriction fragment length polymorphism was used to analyze the genotype polymorphism in T29C. RESULTS: The frequency of initially combined response was markedly higher in both the T/T and TIC groups than in the C/C group (Z=10.326, P=0.006 and Z=26.247, P=0.000, respectively). In addition, the initial virological response was higher in the T/T and T/C groups than the C/C group (chi(2)=5.674, P=0.017 and chi(2)=4.980, P=0.026, respectively). In 78 initially HBeAg-positive patients, however, the frequency of initial e-antigen disappearance or seroconversion among the T/T, T/C, and C/C genotype groups was 34.15%, 27.78% and 15.79%, respectively, which were not significantly different. CONCLUSION. The T29C genotype polymorphism of ESR1 is associated with the initial response to IFN-alpha in patients with chronic hepatitis B, and might be a significant marker for predicting the initial response to IFN-alpha, at least in this study population. (Hepatobiliary Pancreat Dis Int 2010; 9: 275-279)

The Relationship of the Expression of Estrogen Receptor in Cartilage Cell and Osteoarthritis Induced by Bilateral Ovariectomy in Guinea Pig

To investigate the estrogen receptor（ER） expression in cartilage cell in the development of oste0arthritis induced by bilateral ovariectomy in guinea pig and to find their relationship. 30 two-month-old female guinea pigs were randomly divided into two groups （n=15 each） ： sham operation （control）group and ovariectomized group （OVX）; Scanning electorne microscope （SEM） and transmission electron microscope （TEM） were obtained to analysis the cartilage degeneration of the hind limb knee joint after 6 and 12 weeks of ovariectomy. Dextran-Coated-Charcoal （DCC） was taken to quantitively detect the expression of ER. The serum levels of estrogen and gestone were detected by immune contest assay. The results showed that ER do exist in the cartilages of the guinea pigs, with higher expression in the control group than in OVX group at the same time point （P〈0. 05）. It was increased also at 12 th week after operation than that of preoperation. The blood serum levels of estrogen and gestone showed a similar tendency to the expression of ER. Joint cartilage degeneration detected by SEM and TEM could be found at 6 th week, but severe degenerative lesions at 12 th week in the OVX group compared with the control group （P〈0.01）. The data suggested that bilateral ovariectomy in guinea pig lead to severe os.teoarthritis which mighgt be related to the lower serum level of estrogen and the downregulation of the expression of ER in the cartilage also.

Effects of estrogen receptor modulators on cytoskeletal proteins in the central nervous system

Estrogen receptor modulators are compounds of interest because of their estrogenic agonistic/antagonistic effects and tissue specificity. These compounds have many clinical applications, particularly for breast cancer treatment and osteoporosis in postmenopausal women, as well as for the treatment of climacteric symptoms. Similar to estrogens, neuroprotective effects of estrogen receptor modulators have been described in different models. However, the mechanisms of action of these compounds in the central nervous system have not been fully described. We conducted a systematic search to investigate the effects of estrogen receptor modulators in the central nervous system, focusing on the modulation of cytoskeletal proteins. We found that raloxifene, tamoxifen, and tibolone modulate some cytoskeletal proteins such as tau, microtuble-associated protein 1（MAP1）, MAP2, neurofilament 38（NF38） by different mechanisms of action and at different levels： neuronal microfilaments, intermediate filaments, and microtubule-associated proteins. Finally, we emphasize the importance of the study of these compounds in the treatment of neurodegenerative diseases since they present the benefits of estrogens without their side effects.

Reduced prostate branching morphogenes,s in stromal fibroblast, but not in epithelial, estrogen receptor a knockout mice

Early studies suggested that estrogen receptor alpha （ERa） is involved in estrogen-mediated imprinting effects in prostate development. We recently reported a more complete ERa knockout （KO） mouse model via mating β-actin Cre transgenic mice with floxed ERa mice. These ACTB-ERaKO male mice showed defects in prostatic branching morphogenesis, which demonstrates that ERa is necessary to maintain proliferative events in the prostate. However, within which prostate cell type ERa exerts those important functions remains to be elucidated. To address this, we have bred floxed ERa mice with either fibroblast-specific protein （FSP）-Cre or probasin-Cre transgenic mice to generate a mouse model that has deleted ERa gene in either stromal fibroblast （FSP-ERaKO） or epithelial （pes-ERaKO） prostate cells. We found that circulating testosterone and fertility were not altered in FSP.ERaKO and pes-ERaKO male mice. Prostates of FSP-ERaKO mice have less branching morphogenesis compared to that of wild-type littermates. Further analyses indicated that loss of stromal ERa leads to increased stromal apoptosis, reduced expression of insulin-likegrowth factor-1 （IGF-1） and FGFIO, and increased expression of BMP4. Collectively, we have established the first in vivo prostate stromal and epithelial selective ERaKO mouse models and the results from these mice indicated that stromal fibroblast ERa plays important roles in prostatic branching morphogenesis via a paracrine fashion. Selective deletion of the ERa gene in mouse prostate epithelial cells by probasin-Cre does not affect the regular prostate development and homeostasis.