To investigate the effect of naringenin on ovariectomy-induced postmenopausal osteoporosis comprehensively and systemically, thirty-two virgin Sprague-Dawley rats about 3-month-old were used and randomly divided into 4 groups: sham control group (Sham), OVX control group (OVX), naringenin treatment group and 17β-estradiol (E2) treatment group. After 12 weeks treatment with different drugs, 24 h urine were collected, organs were weighed and the organ indies were computed. Uterine pathological changes were observed by making paraffin section. Biochemical parameters and bone turnover markers: serum osteocalcin (BGP) and urine deoxypyridinoline (DPD) were analyzed with automatic biochemical analyzer or ELISA assay. Bone mineral density (BMD) and bone mineral content (BMC) were analyzed by DEXA, bone biomechanical properties was measured by three point bending test and the trabecular bone microarchitecture was evaluated by Micro CT. From the results, we can see that: the gaining of weight and the increasing of bone turnover markers such as serum BGP and urinary DPD could be inhibited by naringenin. The treatment could also enhance the bone strength and prevent the deterioration of trabecular microarchitecture, increase the bone volume, trabecular number and thickness, and decrease the trabecular space. The effects mentioned above were not accompanied with stimulating effects on uterus. Long-term using of naringenin had no obvious influence on other organs and the liver and kidney functions. The study suggests that naringenin had obvious antiosteoporotic effect on ovariectomized rats and it had the potential value for the treatment of postmenopausal osteoporosis.
Amino Acids ; urine ; Animals ; Bone Density ; Disease Models, Animal ; Estradiol ; pharmacology ; Estrogen Antagonists ; pharmacology ; Female ; Flavanones ; pharmacology ; Osteocalcin ; blood ; Osteoporosis ; drug therapy ; Ovariectomy ; Rats ; Rats, Sprague-Dawley ; Uterus ; pathology

Estrogen receptor beta (ERβ) is one of the two key receptors (ERα, ERβ) that facilitate biological actions of 17β-estradiol (E2). ERβ is widely expressed in many tissues, and its expression is reduced or lost during progression of many tumors. ERβ facilitates estrogen signaling by both genomic (classical and non-classical) and extra-nuclear signaling. Emerging evidence suggests that ERβ functions as a tissue-specific tumor suppressor with anti-proliferative actions. Recent studies have identified a number of naturally available selective ERβ agonists. Targeting ERβ using its naturally available ligands is an attractive approach for treating and preventing cancers. This review presents the beneficial actions of ERβ signaling and clinical utility of several natural ERβ ligands as potential cancer therapy.
Antineoplastic Agents, Phytogenic ; pharmacology ; therapeutic use ; Equol ; pharmacology ; therapeutic use ; Estrogen Receptor beta ; antagonists & inhibitors ; metabolism ; Flavanones ; pharmacology ; therapeutic use ; Genistein ; pharmacology ; therapeutic use ; Glycyrrhiza ; chemistry ; Humans ; Ligands ; Neoplasms ; drug therapy ; metabolism ; Phytotherapy ; Plant Extracts ; pharmacology ; therapeutic use ; Soybeans ; chemistry

Carnosol has been proved to have anti-breast cancer effect in previous research. But its ER subtype's specific regulation and mediation mechanisms remain unclear. The aim of this study is to observe the effect of carnosol on cell proliferation and its estrogen receptor α and β's specific regulation and mediation mechanisms with ER positive breast cancer T47D cell. With estrogen receptor α and β antagonists MPP and PHTPP as tools, the MTT cell proliferation assay was performed to observe the effect of carnosol on T47D cell proliferation. The changes in the T47D cell proliferation cycle were detected by flow cytometry. The effect of carnosol on ERα and ERβ expressions of T47D cells was measured by Western blot. The findings showed that 1 x 10(-5)-1 x 10(-7) mol x L(-1) carnosol could significantly inhibit the T47D cell proliferation, which could be enhanced by MPP or weakened by PHTPP. Meanwhile, 1 x 10(-5) mol x L(-1) or 1 x 10(-6) mol x L(-1) carnosol could significantly increase ERα and ERβ expressions of T47D cells, and remarkably increase ERα/ERβ ratio. The results showed that carnosol showed the inhibitory effect on the proliferation of ER positive breast cancer cells through target cell ER, especially ERβ pathway. In the meantime, carnosol could regulate expressions and proportions of target cell ER subtype ERα and ERβ.
Blotting, Western ; Breast Neoplasms ; metabolism ; pathology ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Diterpenes, Abietane ; chemistry ; pharmacology ; Dose-Response Relationship, Drug ; Estrogen Receptor Modulators ; pharmacology ; Estrogen Receptor alpha ; antagonists & inhibitors ; metabolism ; Estrogen Receptor beta ; antagonists & inhibitors ; metabolism ; Female ; Flow Cytometry ; Humans ; Molecular Structure ; Pyrazoles ; pharmacology ; Pyrimidines ; pharmacology

PURPOSE: Limited studies have shown antifibrotic effects of pentoxifylline, captopril, simvastatin, and tamoxifen. No comparisons are available of the effects of these drugs on prevention of renal and bladder changes in partial urethral obstruction (PUO). MATERIALS AND METHODS: The rats were divided into six groups (n=7). The sham-operated rats (group I) only underwent laparotomy and did not receive any treatments. The PUO groups (group II-VI) received normal saline (PUO+NS), pentoxifylline (100 mg/kg/d; PUO+PEN), captopril (35 mg/kg/d; PUO+CAP), simvastatin (15 mg/kg/d; PUO+SIM), or tamoxifen (10 mg/kg/d; PUO+TAM) by gavage for 28 days. Then, the volume and/or length of the kidney components (tubules, vessels, and fibrous tissue) and the bladder components (epithelial and muscular layers, fibrous tissue, fibroblast and fibrocyte number) were quantitatively evaluated on the microscopic sections by use of stereological techniques. RESULTS: The volume of renal and bladder fibrosis was significantly ameliorated in the PUO+PEN group, followed by the PUO+CAP, PUO+SIM, and PUO+TAM groups. Also, the volume and length of the renal tubules and vessels and bladder layers were more significantly protected in the PUO+PEN group, followed by the PUO+CAP, PUO+SIM, and PUO+TAM groups. CONCLUSIONS: Treatment of PUO with PEN was more effective in the prevention of renal and bladder fibrosis and in the preservation of renal and bladder structures.
Angiotensin-Converting Enzyme Inhibitors/pharmacology ; Animals ; Captopril/*pharmacology ; Disease Models, Animal ; Estrogen Antagonists/pharmacology ; Free Radical Scavengers/pharmacology ; Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology ; Kidney/*drug effects/pathology ; Male ; Pentoxifylline/*pharmacology ; Rats ; Simvastatin/*pharmacology ; Tamoxifen/*pharmacology ; Urethral Obstruction/*drug therapy ; Urinary Bladder Neck Obstruction/*drug therapy

ER-α36 is a novel 36-kDa variant of ER-α. A large of evidence demonstrated that ER-α36 responded to membrane-initiated estrogen signaling pathways which were involved in the physiological and pathological process in many kinds of cells. In this study, knock-down of ER-α36 expression in pheochromocytoma (PC12) cells (named as PC12-36L cells) by using the shRNA method was used to evaluate the relationship between ER-α36 and Akt in neurons under glucose deprivation. The effect of ER-α36 on outgrowth of PC12 cells, as well as the neuroprotective effect of ER-α36 on injured PC12 cells exposed to glucose deprivation was observed by using MTT assay, Western blot and Annexin V/PI staining et al. The results showed that, (1) Glucose deprivation induced by MEM treatment for 6 h reduced survival rate and increased apoptotic rate in PC12 cells significantly compared to control group (P < 0.01); and it produced a decrease in the expression of Glut-4 protein (P < 0.01); (2) The expression level of ER-α36 was decreased significantly at 3 h of glucose deprivation, and then increased, while phosphorylation of Akt participated in the glucose deprivation was increased at first and then reduced; LY294002 (PI3K inhibitor) contributed to decreased expression of ER-α36, and suppressed the activation of Akt; (3) The rate of apoptosis was significantly increased in PC12-36L cells after glucose deprivation compared with that in wild type PC12 cells (P < 0.01). Furthermore, phosphorylation of Akt was decreased and Caspase-3 was increased by glucose deprivation in PC12-36L cells compared with those in wild type PC12 cells. The study reveals that phosphorylation of Akt is associated with ER-α36 in PC12 cells exposed to glucose deprivation, and both are involved in the regulation of stress responses.
Animals ; Apoptosis ; Caspase 3 ; metabolism ; Chromones ; pharmacology ; Culture Media ; chemistry ; Estrogen Receptor alpha ; metabolism ; Glucose ; chemistry ; Morpholines ; pharmacology ; PC12 Cells ; Phosphatidylinositol 3-Kinases ; antagonists & inhibitors ; Phosphorylation ; Proto-Oncogene Proteins c-akt ; metabolism ; Rats ; Signal Transduction

The localization of estrogen (E2) has been clearly shown in hippocampus, called local hippocampal E2. It enhanced neuronal synaptic plasticity and protected neuron form cerebral ischemia, similar to those effects of exogenous E2. However, the interactive function of hippocampal and exogenous E2 on synaptic plasticity activation and neuroprotection is still elusive. By using hippocampal H19-7 cells, we demonstrated the local hippocampal E2 that totally suppressed by aromatase inhibitor anastrozole. Anastrozole also suppressed estrogen receptor (ER)beta, but not ERalpha, expression. Specific agonist of ERalpha (PPT) and ERbeta (DPN) restored ERbeta expression in anastrozole-treated cells. In combinatorial treatment with anastrozole and phosphoinositide kinase-3 (PI-3K) signaling inhibitor wortmannin, PPT could not improve hippocampal ERbeta expression. On the other hand, DPN induced basal ERbeta translocalization into nucleus of anastrozole-treated cells. Exogenous E2 increased synaptic plasticity markers expression in H19-7 cells. However, exogenous E2 could not enhance synaptic plasticity in anastrozole-treated group. Exogenous E2 also increased cell viability and B-cell lymphoma 2 (Bcl2) expression in H2O2-treated cells. In combined treatment of anastrozole and H2O2, exogenous E2 failed to enhance cell viability and Bcl2 expression in hippocampal H19-7 cells. Our results provided the evidence of the priming role of local hippocampal E2 on exogenous E2-enhanced synaptic plasticity and viability of hippocampal neurons.
Androstadienes/pharmacology ; Animals ; Aromatase Inhibitors/pharmacology ; Cell Line ; Cell Survival/drug effects ; Estrogen Receptor alpha/agonists/metabolism ; Estrogen Receptor beta/agonists/metabolism ; Estrogens/*metabolism/pharmacology ; Hippocampus/cytology/*metabolism ; Hydrogen Peroxide/pharmacology ; Nervous System/*drug effects ; Neuronal Plasticity/*drug effects ; *Neuroprotective Agents ; Nitriles/pharmacology ; Phosphatidylinositol 3-Kinase/antagonists & inhibitors ; Proto-Oncogene Proteins c-bcl-2/biosynthesis ; Rats ; Triazoles/pharmacology

Estrogen has anti-colorectal cancer effects which are thought to be mediated by mismatch repair gene (MMR) activity. Estrogen receptor (ER) expression is associated with microRNA (miRNA) expression in ER-positive tumors. However, studies of direct link between estrogen (especially estradiol E2), miRNA expression, and MMR in colorectal cancer (CRC) have not been done. In this study, we first evaluated the effects of estradiol (E2) and its antagonist ICI182,780 on the expression of miRNAs (miR-31, miR-155 and miR-135b) using COLO205, SW480 and MCF-7 cell lines, followed by examining the association of tissue miRNA expression and serum E2 levels using samples collected from 18 colorectal cancer patients. E2 inhibited the expressions of miRNAs in COLO205 cells, which could be reversed by E2 antagonist ICI 182.780. The expression of miR-135b was inversely correlated with serum E2 level and ER-beta mRNA expression in CRC patients' cancer tissues. There were significant correlations between serum E2 level and expression of ER-beta, miR-135b, and MMR in colon cancer tissue. This study suggests that the effects of estrogen on MMR function may be related to regulating miRNA expression via ER-beta, which may be the basis for the anti-cancer effect in colorectal cells.
Adaptor Proteins, Signal Transducing/genetics/metabolism ; Adult ; Aged ; Cell Line, Tumor ; Colorectal Neoplasms/*genetics/metabolism ; DNA Mismatch Repair/*genetics ; Estradiol/analogs & derivatives/blood/*pharmacology ; Estrogen Antagonists/pharmacology ; Estrogen Receptor beta/genetics/*metabolism ; Female ; *Gene Expression Regulation, Neoplastic ; Humans ; Male ; MicroRNAs/genetics/*metabolism ; Middle Aged ; MutS Homolog 2 Protein/genetics/metabolism ; Nuclear Proteins/genetics/metabolism ; RNA, Messenger/biosynthesis

The aim of the present study was to investigate the involvements of insulin-like growth factor-1 (IGF-1) and estrogen receptor α (ERα) in the inhibitory effect of wogonin on the breast adenocarcinoma growth. Moreover, the effect of wogonin on the angiogenesis of chick chorioallantoic membrane (CAM) was also investigated. MCF-7 cells (human breast adenocarcinoma cell line) were subjected to several drugs, including IGF-1, wogonin and ER inhibitor ICI182780, alone or in combination. MTT assay was used to detect breast cancer proliferation. Western blot was used to analyze ERα and p-Akt expression levels. CAM models prepared from 6-day chicken eggs were employed to evaluate angiogenesis inhibition. The results showed wogonin and ICI182780 both exhibited a potent ability to blunt IGF-1-stimulated MCF-7 cell growth. Either of wogonin and ICI182780 significantly inhibited ERα and p-Akt expressions in IGF-1-treated cells. The inhibitory effect of wogonin showed no difference from that of ICI182780 on IGF-1-stimulated expressions of ERα and p-Akt. Meanwhile, wogonin at different concentrations showed significant inhibitory effect on CAM angiogenesis. These results suggest the inhibitory effect of wogonin on breast adenocarcinoma growth via inhibiting IGF-1-mediated PI3K-Akt pathway and regulating ERα expression. Furthermore, wogonin has a strong anti-angiogenic effect on CAM model.
Adenocarcinoma ; metabolism ; pathology ; Angiogenesis Inhibitors ; pharmacology ; Animals ; Breast Neoplasms ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Chick Embryo ; Chorioallantoic Membrane ; blood supply ; Estrogen Receptor alpha ; genetics ; metabolism ; Female ; Flavanones ; pharmacology ; Humans ; Insulin-Like Growth Factor I ; antagonists & inhibitors ; pharmacology ; Scutellaria ; chemistry

The aim of the present study was to study the effect of β-estradiol (β-E(2)) on the large-conductance Ca(2+)-activated potassium (BK(Ca)) channel in mesenteric artery smooth muscle cells (SMCs). The mesenteric arteries were obtained from post-menopause female patients with abdominal surgery, and the SMCs were isolated from the arteries using an enzymatic disassociation. According to the sources, the SMCs were divided into non-hypertension (NH) and essential hypertension (EH) groups. Single channel patch clamp technique was used to investigate the effect of β-E(2) and ICI 182780 (a specific blocker of estrogen receptor) on BK(Ca) in the SMCs. The results showed the opening of BK(Ca) in the SMCs was voltage and calcium dependent, and could be blocked by IbTX. β-E(2) (100 μmol/L) significantly increased open probability (Po) of BK(Ca) in both NH and EH groups. After β-E(2) treatment, NH group showed higher Po of BK(Ca) compared with EH group. ICI 182780 could inhibit the activating effect of β-E(2) on BK(Ca) in no matter NH or EH groups. These results suggest β-E(2) activates BK(Ca) in mesenteric artery SMCs from post-menopause women via estrogen receptor, but hypertension may decline the activating effect of β-E(2) on BK(Ca).
Aged ; Estradiol ; analogs & derivatives ; pharmacology ; Female ; Humans ; Hypertension ; physiopathology ; Large-Conductance Calcium-Activated Potassium Channels ; agonists ; metabolism ; physiology ; Mesenteric Arteries ; metabolism ; physiology ; Middle Aged ; Muscle, Smooth, Vascular ; cytology ; metabolism ; physiology ; Patch-Clamp Techniques ; Postmenopause ; physiology ; Receptors, Estrogen ; antagonists & inhibitors

Soy-isoflavones may act as estrogenic agonists or antagonists depending on the endogenous hormone status. These clinical effects can be exerted variably in individuals by the metabolic ability to produce a more potent metabolite than precursors. The objective of this randomized, double-blind, placebo-controlled study was to investigate the skeletal effect of isoflavones according to their metabolic variability in premenopausal women. Volunteers were randomly assigned to receive either soy-extract isoflavones (n=32) or lactose (n=21) once a day for three menstrual cycles. After intervention, the urinary excretions of isoflavones and their metabolites were significantly higher in the soy group than in the placebo group and showed a large inter-individual variation. Women in the soy group were divided into subgroups according to their ability to excrete more potent metabolites. Serum osteocalcin and urine deoxypyridinoline showed a tendency to increase after a challenge in equol high-excretors. Serum osteocalcin concentration in the genistein high-excretors increased significantly after a challenge (P=0.04) but did not increase in either the placebo or genistein low-excretors. An estrogenic antagonistic effect of isoflavones on bone turnover was observed in premenopausal women who are able to produce more potent metabolites.
Adult ; Amino Acids/urine ; Bone and Bones/*drug effects/metabolism ; Double-Blind Method ; Estrogen Antagonists/*pharmacokinetics/pharmacology/urine ; Female ; Humans ; Isoflavones/*pharmacokinetics/pharmacology/urine ; Middle Aged ; Osteocalcin/blood ; *Premenopause