OBJECTIVETo establish a human breast cancer MCF-7 cell model stably overexpressing the aromatase gene (MCF-7-aromatase) and aromatase inhibitor letrozole-resistant MCF-7 cell model (MCF-7-LR).

METHODSWe utilized the lentivirus-mediated gene transfer approach to establish MCF-7-aromatase cell and MCF-7 cell model stably overexpressing green fluorescent protein (GFP) (MCF-7-GFP). The expression of aromatase in the MCF-7-aromatase and MCF-7-GFP cells was determined by reverse transcription polymerase chain reaction (RT-PCR), real time quantitative PCR (RT-qPCR), Western blot and immunoprecipitation (IP) assay. The proliferative ability in vitro of MCF-7-aromatase and MCF-7-GFP cells treated with testostorone and β-estradiol (E2) was determined by WST-1 cell proliferation assay. The proliferative ability of MCF-7-aromatase cells treated with letrozole was determined by WST-1 assay. The half maximal inhibitory concentration (IC50 value) for letrozole was calculated from the nonlinear regression line of the plot of cell viability (percentage of control) versus letrozole concentration using Graphpad Prism software. MCF-7-aromatase cells were continuously cultured in the presence of testosterone and letrozole, thus letrozole-resistant MCF-7-LR cells were obtained. WST-1 assay was performed to determine their chemoresistance to letrozole.

RESULTSRT-PCR and RT-qPCR results revealed that the mRNA expression of aromatase was significantly increased in the MCF-7-aromatase cells compared with that in the MCF-7-GFP cells. Both Western blot and IP assays showed that the expression of aromatase protein was drastically increased in the MCF-7-aromatase cells, compared with that in the MCF-7-GFP cells. WST-1 assay showed that the cell proliferation rate of MCF-7-aromatase cells treated with 1 and 10 nmol/L testosterone was 1.43- and 1.53-fold higher than that of the control cells, respectively. The proliferation rate of MCF-7-aromatase cells treated with 1 and 10 nmol/L E2 was 1.41- and 1.55-fold higher than that of the control cells, respectively. In contrast, the proliferation rate of MCF-7-GFP cells treated with 10 nmol/L testosterone was 1.12-fold higher than that of the control cells, and the proliferation rate of MCF-7-GFP cells treated with 1 and 10 nmol/L E2 was 1.41- and 1.51-fold higher than that of the control cells, respectively. Letrozole treatment significantly inhibited the testosterone-induced proliferation ability of MCF-7-aromatase cells in a dose-dependent manner and the IC50 value was 5.3 nmol/L. In contrast, letrozole treatment showed no inhibitory effect on the proliferative ability of MCF-7-LR cells and the IC50 value was >1000 nmol/L.

CONCLUSIONSMCF-7-aromatase and MCF-7-LR cells exhibit different response to letrozole treatment, which provides an important basis for further investigating the mechanism of letrozole resistance.

Antineoplastic Agents ; pharmacology ; Aromatase ; metabolism ; Aromatase Inhibitors ; pharmacology ; Breast Neoplasms ; Cell Proliferation ; Drug Resistance, Neoplasm ; Humans ; MCF-7 Cells ; Models, Biological ; Nitriles ; pharmacology ; Triazoles ; pharmacology

Aromatase is a key enzyme responsible for in vivo estrogen biosynthesis. Inhibition of the activity of the aromatase has become an alterative way for treatment of breast cancer. In this review, the structure and catalytic mechanism of the aromatase is briefly introduced followed by thorough review of the progress in the study of the steroidal and non-steroidal aromatase inhibitors. This review is focused on the natural compounds that exhibit the aromatase inhibition, which include flavonoids, xanthones, coumarins, and sesquiterpenes. The structure-activity relationship of these compounds is also discussed.
Androstenedione ; analogs & derivatives ; Antineoplastic Agents ; chemistry ; pharmacology ; therapeutic use ; Aromatase ; chemistry ; metabolism ; pharmacology ; Aromatase Inhibitors ; chemistry ; classification ; pharmacology ; therapeutic use ; Breast Neoplasms ; drug therapy ; Catalysis ; Coumarins ; chemistry ; pharmacology ; Estrogens ; biosynthesis ; Flavonoids ; chemistry ; pharmacology ; Humans ; Inhibitory Concentration 50 ; Nitriles ; chemistry ; pharmacology ; Sesquiterpenes ; chemistry ; pharmacology ; Structure-Activity Relationship ; Triazoles ; chemistry ; pharmacology ; Xanthones ; chemistry ; pharmacology

OBJECTIVE: This study aimed to compare 9 perfluoroalkyl sulfonic acids (PFSA) with carbon chain lengths (C4-C12) to inhibit human placental 3β-hydroxysteroid dehydrogenase 1 (3β-HSD1), aromatase, and rat 3β-HSD4 activities. METHODS: Human and rat placental 3β-HSDs activities were determined by converting pregnenolone to progesterone and progesterone secretion in JEG-3 cells was determined using HPLC/MS-MS, and human aromatase activity was determined by radioimmunoassay. RESULTS: PFSA inhibited human 3β-HSD1 structure-dependently in the order: perfluorooctanesulfonic acid (PFOS, half-maximum inhibitory concentration, IC ₅₀: 9.03 ± 4.83 μmol/L) > perfluorodecanesulfonic acid (PFDS, 42.52 ± 8.99 μmol/L) > perfluoroheptanesulfonic acid (PFHpS, 112.6 ± 29.39 μmol/L) > perfluorobutanesulfonic acid (PFBS) = perfluoropentanesulfonic acid (PFPS) = perfluorohexanesulfonic acid (PFHxS) = perfluorododecanesulfonic acid (PFDoS) (ineffective at 100 μmol/L). 6:2FTS (1H, 1H, 2H, 2H-perfluorooctanesulfonic acid) and 8:2FTS (1H, 1H, 2H, 2H-perfluorodecanesulfonic acid) did not inhibit human 3β-HSD1. PFOS and PFHpS are mixed inhibitors, whereas PFDS is a competitive inhibitor. Moreover, 1-10 μmol/L PFOS and PFDS significantly reduced progesterone biosynthesis in JEG-3 cells. Docking analysis revealed that PFSA binds to the steroid-binding site of human 3β-HSD1 in a carbon chain length-dependent manner. All 100 μmol/L PFSA solutions did not affect rat 3β-HSD4 and human placental aromatase activity. CONCLUSION Carbon chain length determines inhibitory potency of PFSA on human placental 3β-HSD1 in a V-shaped transition at PFOS (C8), with inhibitory potency of PFOS > PFDS > PFHpS > PFBS = PFPS = PFHxS = PFDoS = 6:2FTS = 8:2FTS.
Humans ; Pregnancy ; Female ; Rats ; Animals ; Placenta ; Progesterone/pharmacology* ; Aromatase/pharmacology* ; Cell Line, Tumor ; Fluorocarbons ; Alkanesulfonic Acids ; Structure-Activity Relationship ; Hydroxysteroid Dehydrogenases/pharmacology*

OBJECTIVETo study the effects of Wenyang Shengjing Decoction (WSD) containing serum on the estradiol (E2) secretion, the synthesized cytochrome P450 aromatase (P450arom) activities, as well as the expression of its encode gene CYP19 in Leydig cells of male sterile rats of adenine induced Shen-yang deficiency (SYD).

METHODSExperimental rats were randomly divided into 4 groups, i.e., the normal control group, the high, middle, and low dose WSD groups, 5 in each group. The normal saline, low, middle, and high dose WSD were respectively given to rats of all groups for 10 successive days. Blood was drawn from rats' heart 2 h after the last gastrogavage. The serum was separated after centrifuge. Leydig cells isolated and purified from SYD rats were primary cultured in vitro and divided into 5 groups in random, i. e., the blank control group, the model group, the high, middle, and low dose WSD groups (1.2, 1.0, and 0.8 g/mL, respectively). The content of E2 released in the culture supernate was determined by radioimmunoassay. The P450arom activity was detected by tritium release assay. Meanwhile, the mRNA and protein expressions of CYP19 were analyzed using fluorescent quantitative PCR and Western blot respectively.

RESULTSCompared with the blank control group, the E2 secretion of the supernate of Leydig cells obviously decreased in the model groups, accompanied with the inhibition of P450arom activities, significant decreased protein and mRNA expressions of CYP19 (P < 0.01, P < 0.05). Compared with the model group, after intervened by WSD containing serum, the E2 secretion in the Leydig cells could be significantly increased, the P450arom activities up-regulated, the CYP19 expressions up-regulated at the protein and mRNA levels partially in a dose-dependent manner (P < 0.01, P < 0.05).

CONCLUSIONSWSD containing serum could effectively elevate the E2 secretion in Leydig cells, which might be partially achieved through up-regulating P450arom activities and enhancing the gene expression of CyP19. This might be one of its mechanisms of action for treating male infertility of SYD.

Animals ; Aromatase ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Estradiol ; secretion ; Leydig Cells ; metabolism ; Male ; Rats ; Rats, Sprague-Dawley ; Serum ; Yang Deficiency ; metabolism

OBJECTIVETo explore the effect mechanism of Sanlengwan (SLW) on estrogen production in ectopic endometrium of rats.

METHODThe rat model of endometriosis was established by surgical implant of endometrial tissue which belong to its body. Forty EMS model rats were randomly divided into five groups (n = 8): model control group, three different concentration SLW groups and anastrozole group. Meanwhile, eight normal rats were used as the normal control group. All the rats were treated for 4 weeks respectively, the changes of the P450 arom and cyclooxygenase-2 protein were measured by immunohistochemical test and western blot respectively before and after treatment of SLW, and the level of secretion of estrodiol and prostaglandin E2 was also measured by ECLIA and RIA.

RESULTSLW can reduce the expression of P450 arom protein, and the levels of estradiol after treatment of SLW were significantly lower than that of the model group in ectopic endometrial tissue (P < 0. 05); The high dose group of SLW can inhibit the expression of cyclooxygenase-2 protein and also reduce the production of prostaglandin E2 (P < 0.05).

CONCLUSIONSLW can reduce the production of estradiol in the ectopic endometrial tissue of rats, and its mechanism might be associated with inhibiting the expression of P450 arom and interruption the positive feedback loop of estradiol production.

Animals ; Aromatase ; metabolism ; Aromatase Inhibitors ; pharmacology ; Cyclooxygenase 2 ; metabolism ; Cyclooxygenase 2 Inhibitors ; pharmacology ; Cytochrome P-450 Enzyme System ; metabolism ; Dinoprostone ; biosynthesis ; Dose-Response Relationship, Drug ; Endometriosis ; enzymology ; pathology ; Endometrium ; drug effects ; metabolism ; Estradiol ; biosynthesis ; Female ; Gene Expression Regulation, Enzymologic ; drug effects ; Rats ; Rats, Wistar

The aim of this paper was to observe the toxic effect of Tripterygium Glycosides Tablets( TG) on the reproductive system of Ⅱ type collagen induced arthritis( CIA) male rats,and to explore the toxic mechanism preliminarily. Fifty SD rats were randomly divided into normal control group( Con),model group( CIA),Tripterygium Glycosides Tablets clinical equivalent dose groups of 1,2,4 times( 9,18,36 mg·kg-1),10 rats in each group,and were given by gavage once a day for 42 days after the first immunization.The organ indexes of uterine and ovarian were calculated on days 21 and 42. Histopathological and morphological changes of uterine and ovarian were observed under optical microscope. The concentration of estradiol( E2),follicle-stimulating hormone( FSH),luteinizing hormone( LH),17α-hydroxylase( CYP17 A1) and cytochrome P450 19 A1( CYP19 A1) in serum were detected by ELISA. Immunohistochemistry was used to observe the expression of Bax and Bcl-2 related proteins in the apoptosis pathway of uterus and ovary. The results showed that compared with the Con group,CIA group could reduce the number of uterine glands( P<0.05),but no significant changes were observed in other groups. Compared with the CIA group,there were no significant changes in the coefficients of uterus and ovary in the Tripterygium Glycosides Tablets groups. The number of uterine glands,total follicles in the ovary,mature follicles and corpus luteum,the distribution of blood vessels and mitochondria had a certain inhibitory trend,and also slightly increased the number of atresia follicles,but the histopathological quantitative indicators were not statistically different. Except that 2 times clinical dose of Tripterygium Glycosides Tablets could significantly reduce the content of CYP19 A1( P<0. 05) after 42 d administration,there were no significant changes in serum estrogen E2,FSH,LH and estrogen synthesis key enzymes CYP17 A1 in each administration group. Medium and high doses of Tripterygium Glycosides Tablets could increase the expression of apoptotic protein Bax in uterine and ovarian tissues( P<0. 05,P<0. 01),and all the administration groups could inhibit the expression of apoptotic inhibiting protein Bcl-2( P <0. 05,P<0. 01,P<0.001),42 d was more obvious than 21 d. In conclusion,4 times and less than 4 times Tripterygium Glycosides Tablets did not cause obvious toxicity and histopathological changes in the reproductive organs of CIA rats,but it could reduce the level of serum estrogen synthesis key enzyme CYP19 A1 and affect the content of apoptosis-related proteins Bax and Bcl-2 in uterus and ovary tissues. The relevant mechanism needs further study.
Animals ; Apoptosis ; Aromatase ; metabolism ; Arthritis, Experimental ; chemically induced ; drug therapy ; Drugs, Chinese Herbal ; pharmacology ; toxicity ; Female ; Genitalia, Female ; drug effects ; Glycosides ; pharmacology ; toxicity ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Tablets ; Tripterygium ; chemistry

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

The mechanisms of high turnover bone loss induced by Cyclosporin A (CsA) are not clearly understood. Deficiencies in sex hormones result in high turnover osteoporosis, and not only androgen but also estrogen plays an important role in maintaining bone mass in men. To study whether or not there are any changes in the levels of sex hormones, aromatization, and the expression of estrogen receptors in CsA-induced osteoporosis, we treated 39 rats with vehicle, low-dose CsA (5 mg/kg) and high dose CsA (15 mg/kg) for 28 days, and measured sex hormone levels by radioimmunoassay. Aromatase activities in ROS cells and 3T3-L1 cells were determined by measuring the conversion rate of 3H-androstenedione into 3H-estrone. ER and ER mRNA were measured by competitive RT-PCR in collected marrow cells and ROS cells. The levels of free testosterone in the serum in low-dose CsA-treated rats were unchanged, but the levels were significantly decreased in those treated with high-dose CsA as previously reported. The levels of total estradiol in the serum were significantly increased in the low-dose CsA-treated group (5 mg/kg) and were comparable to levels of the control group in the high-dose CsA-treated group (15 mg/kg). CsA increased the conversion of 3H-androstenedione to 3H-estrone in ROS cells, but not in 3T3-L1 cells. Meanwhile, CsA treatment did not change the rates of ER or ER mRNA expression in ROS cells or in collected bone marrow cells. In conclusion, CsA treatment decreased the level of free testosterone in the serum, but did not decrease the level of serum estradiol by enhancing aromatization. High-turnover osteoporosis induced by clinical dosage CsA treatment may not be caused by lowering the levels of circulating estrogen or by decreasing the expression of estrogen receptors.
3T3 Cells ; Animal ; Aromatase/metabolism ; Bone Marrow Cells/metabolism ; Cell Line ; Cyclosporine/pharmacology* ; Cyclosporine/adverse effects ; Male ; Mice ; Osteoporosis/chemically induced ; Rats ; Rats, Sprague-Dawley ; Receptors, Estrogen/metabolism* ; Sex Hormones/metabolism* ; Sex Hormones/blood

AIMTo investigate the effects of 17beta-estradiol (E2), Peganum harmala extract (PHE) and caloric restriction (CR) on various testis parameters during aging.

METHODSTwelve month-old male rats were treated for 6 months with either E2 or PHE, or submitted to CR (40%).

RESULTSOur results show that estrogens and CR are able to protect the male gonad by preventing the decrease of testosterone and E2 levels as well as the decrease of aromatase and estrogen receptor gene expressions. Indeed, E2, PHE and CR treatments induced an increase in the superoxide dismutase activities and decreased the activity of testicular enzymes: gamma-glutamyl transferase, alkaline phosphatase, lactate deshydrogenase as well as the aspartate and lactate transaminases in aged animals. In addition, the testicular catalase and gluthatione peroxidase activities were enhanced in E2, PHE and CR-treated rats compared to untreated animals at 18 months of age. Moreover, the positive effects of estradiol, PHE and CR were further supported by a lower level of lipid peroxidation. Recovery of spermatogenesis was recorded in treated rats.

CONCLUSIONBesides a low caloric diet which is beneficial for spermatogenesis, a protective antioxydant role of estrogens is suggested. Estrogens delay testicular cell damage, which leads to functional senescence and, therefore, estrogens are helpful in protecting the reproductive functions from the adverse effects exerted by reactive oxygen species (ROS) produced in large quantities in the aged testis.

Aging ; physiology ; Animals ; Antioxidants ; metabolism ; Aromatase ; biosynthesis ; genetics ; Caloric Restriction ; Estradiol ; metabolism ; pharmacology ; Estrogens ; pharmacology ; Lipid Peroxidation ; drug effects ; Male ; Oxidative Stress ; drug effects ; Peganum ; chemistry ; Plant Extracts ; pharmacology ; RNA ; biosynthesis ; genetics ; Rats ; Rats, Wistar ; Receptors, Estrogen ; biosynthesis ; genetics ; Testis ; drug effects ; enzymology ; growth & development ; Testosterone ; metabolism ; Thiobarbituric Acid Reactive Substances ; metabolism

At present, there is no reliable in vitro assembled prepubertal testis-like biomimetic organ culture system designed to assess the functional effects of human gonadotropins on Sertoli and Leydig cells. Spermatogenesis is regulated by endocrine, paracrine, and juxtacrine factors (testicular cross-talk), mainly orchestrated by gonadotropins such as luteinizing hormone (LH) and follicle-stimulating hormone (FSH) that play a pivotal role by stimulating Leydig and Sertoli cells, respectively. The aim of our study was to set up an in vitro prepubertal porcine bioengineered construct as a new model for experimental studies on reassembled Sertoli and Leydig cells. We have evaluated Sertoli and Leydig cells obtained from 15- to 20-day-old neonatal pig testes in terms of purity and function. Subsequently, purified Sertoli and enriched Leydig cells were subjected to coincubation to obtain an in vitro prepubertal porcine testis-like culture system. We performed enzyme-linked immunosorbent assay (ELISA) for anti-Müllerian hormone (AMH), inhibin B, and testosterone secretion in the medium, and Real-Time PCR analysis of AMH, inhibin B, FSH-r, aromatase, LHr, and 3β-HSD mRNA expression levels. This in vitro testis-like system was highly responsive to the effects of human gonadotropins and testosterone. AMH mRNA expression and secretion declined, and inhibin-B increased, while FSH-receptor expression was downregulated upon FSH/LH exposure/treatment. Finally, the production of testosterone was increased selectively upon LH treatment. In summary, our proposed model could help to better determine the action of human gonadotropins on Sertoli and Leydig cells. The potential usefulness of the system for shedding light into male infertility-related issues is evident.
3-Hydroxysteroid Dehydrogenases/metabolism* ; Animals ; Animals, Newborn ; Anti-Mullerian Hormone/metabolism* ; Aromatase/metabolism* ; Cell Culture Techniques ; Enzyme-Linked Immunosorbent Assay ; Follicle Stimulating Hormone/pharmacology* ; Hormones/pharmacology* ; In Vitro Techniques ; Inhibins/metabolism* ; Leydig Cells/metabolism* ; Luteinizing Hormone/pharmacology* ; Male ; Models, Biological ; Real-Time Polymerase Chain Reaction ; Receptors, FSH/metabolism* ; Receptors, LH/metabolism* ; Sertoli Cells/metabolism* ; Swine ; Testis/metabolism* ; Testosterone/metabolism*