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1.
Estrone (E1), 17β-estradiol (E2) and 17α-ethynylestradiol (EE2) discharged from sewage treatment plants (STPs) into surface
waters, are seen as a threat effecting aquatic life by its estrogenic character. Therefore, much research is conducted on
the fate and removal of these compounds. Since these compounds are present in influents and effluents in the ng/l range, methods
for detection deserve special attention. Most important processes that play a role in the removal of estrogens are: adsorption,
aerobic degradation, anaerobic degradation, anoxic biodegradation and photolytic degradation. Halflifes tend to vary and are
remarkably shorter when low initial concentrations are applied. In general anaerobic conditions result in longer halflifes
then aerobic conditions. EE2 shows far most persistence of the compounds, thereby also the estrogenic effect in vitro is about 2–3-fold higher compared to E2. The three compounds show a higher affinity to sorb to sludge compared to other tested
adsorption materials like sediment. Aerobic degradation is far the most efficient in removing these compounds, but adsorption
seems to play a significant role in retaining the estrogens inside full-scale STPs. Removal rates in full scale plants depend
on the HRT, SRT and loading rates, but lack of information on the exact dependency so far prevents an optimal design able
to fully eliminate estrogens from wastewater. 相似文献
2.
Bai W Oliveros-Saunders B Wang Q Acevedo-Duncan ME Nicosia SV 《In vitro cellular & developmental biology. Animal》2000,36(10):657-666
Summary Ovarian cancer is the leading cause of gynecological cancer mortality, and 85–90% of this malignancy originates from the ovarian
surface epithelium (OSE). The etiology of ovarian epithelial cancer is unknown but a role for estrogens has been suspected.
However, the effect of estrogens on OSE cell proliferation remains to be determined. Using the rabbit model, our studies have
demonstrated that 17β-estradiol stimulates OSE cell proliferation and the formation of a papillary ovarian surface morphology
similar to that seen in human ovarian serous neoplasms of low malignant potential. Immunohistochemical staining of ovarian
tissue sections with an antibody to the estrogen receptor α demonstrates its expression in both OSE cells and stromal interstitial
cells. In primary ovarian cell cultures, the proliferative response of the epithelial cells to 17β-estradiol depends on the
expression of the estrogen receptor α in the epithelial cells. However, when the epithelial cells are grown together with
ovarian stromal cells, their proliferative response to this hormone is greatly enhanced, suggesting the involvement of stromal-epithelial
interactions. These studies suggest a role for estrogens and the estrogen receptor α in OSE growth. 相似文献
3.
Esfahani A Kendall CW Bashyam B Archer MC Jenkins DJ 《In vitro cellular & developmental biology. Animal》2010,46(10):856-862
The majority of cell culture studies have assessed the effect of hormones on cancer cell growth using media supplemented with
charcoal-treated fetal bovine serum (CTS). We aimed to determine whether using a system more reflective of the human condition
by changing the charcoal-treated serum to an untreated pooled human serum (PHS) resulted in the same hormone responses in
breast and prostate cell lines. MCF-7 breast cancer, MCF-10A non-transformed breast, and LNCaP prostate cancer cell lines
supplemented with PHS were treated with high and low physiological concentrations of six hormones (17β-estradiol, dehydroepiandosterone
(DHEA), dihydrotestosterone (DHT), testosterone, insulin, and glucagon). Cell growth was measured after 72 h of incubation.
All hormones stimulated growth of MCF-7 cells (p < 0.05). MCF-10A cell growth was inhibited by DHEA, DHT, and testosterone (p < 0.05), unaffected by 17β-estradiol and glucagon, and stimulated by insulin (p < 0.05). LNCaP cell growth was stimulated by the highest concentration of DHEA and DHT (p < 0.05) and inhibited by the highest concentration of 17β-estradiol (p < 0.05), while insulin and testosterone, had no effect. Overall, PHS lowered the magnitude of the effect of hormones on cell
growth in comparison to CTS. Due to the presence of all serum constituents, our model represents a more appropriate physiological
environment for determining the effect of hormones on cancer cell growth. Further studies are required to determine the mechanisms
by which added hormones interact with the constituents of untreated human serum. 相似文献
4.
Plasma Sex Steroid Levels and Steroidogenesis in the Gonad of the Self-fertilizing Fish Rivulus marmoratus 总被引:1,自引:0,他引:1
Masako Minamimoto Yoshitaka Sakakura Kiyoshi Soyano Yoshiaki Akaba Atsushi Hagiwara 《Environmental Biology of Fishes》2006,75(2):159-166
Synopsis The mangrove killifish, Rivulus marmoratus, is the only known self-fertilizing vertebrate. This species is sexually dimorphic; sexually mature individuals are either
hermaphrodite or primary and secondary males. Although the mangrove killifish has a unique reproductive strategy, there has
been no study on the reproductive endocrinology of this species. Thus we investigated plasma sex steroid hormone levels and
steroidogenesis in the gonads of R. marmoratus by enzyme linked immunosorbent assay (ELISA). Plasma 17β-estradiol (E2) and 11-ketotestosterone (11-KT) were detected both
in hermaphrodite and in primary male. Ovarian follicles (follicle-enclosed oocytes) from hermaphrodites, which were categorized
into early yolk stage and late yolk stage, and testis tissue of primary males were cultured with different concentrations
of 17α-hydroxyprogesterone (OHP) or testosterone (T) for 24 h. Production of T, E2, 11-KT and 17α-20 β-dihydroxy-4-pregnen-3-one
(17α,20β-P) in the medium from tissue culture were measured by ELISA. Early and late ovarian follicles of hermaphrodites and
testis pieces of primary males synchronously secreted E2, 11-KT, and 17α,20β-P following incubation with OHP or T. We conclude
that both hermaphrodite and primary male of the mangrove killifish secrete estrogen, androgen, and progestin synchronously. 相似文献
5.
Bogush TA Dudko EA Beme AA Bogush EA Kim AI Polotsky BE Tjuljandin SA Davydov MI 《Biochemistry. Biokhimii?a》2010,75(12):1421-1427
This review considers data on expression of different types of estrogen receptors (ERα and ERβ) in in vitro cultured cells of non-small cell lung cancer and also in human and animal lung tumors. Estrogens are shown to play an important
role in genesis and development of non-small cell lung cancer because the estrogen-stimulated cell proliferation as well as
antiestrogen-caused inhibition of proliferation occurred only in the cells expressing different types of estrogen receptors.
In general, the situation is similar to that observed in breast cancer, but in the cells of non-small cell lung cancer not
ERα are expressed in more than half of cases but ERβ. Just estrogen receptors β play the crucial role in inducing cell proliferation
in response to estrogens, and ERβ is a prognostic marker of a favorable course of non-small cell lung cancer. Data on the
interactions between ER and EGFR signaling pathways, as well as on the additive antitumor effect of antiestrogens (tamoxifen
and fulvestrant) combined with tyrosine kinase inhibitors (gefitinib, erlotinib, and vandetanib) are considered. The review
also includes data on the influence of estrogens on genesis and development of lung cancer in humans and animals and the frequency
of ERα and ERβ expression in non-small cell lung cancer in tissues from patients of the two sexes. Problems of quantitative
determination of α and β estrogen receptors in the tumor cells are also discussed. 相似文献
6.
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8.
Pharmaceuticals are an important group of emerging pollutants with increasing interest due to their rising consumption and
the evidence for ecotoxicological effects associated to trace amounts in aquatic environments. In this paper, we assessed
the potential degradation of a series of pharmaceuticals: antibiotics (sulfamethoxazole), antidepressives (citalopram hydrobromide
and fluoxetine hydrochloride), antiepileptics (carbamazepine), anti-inflammatory drugs (diclofenac and naproxen) and estrogen
hormones (estrone, 17β-estradiol, 17α-ethinylestradiol) by means of a versatile peroxidase (VP) from the ligninolytic fungus
Bjerkandera adusta. The effects of the reaction conditions: VP activity, organic acid concentration and H2O2 addition rate, on the kinetics of the VP based oxidation system were evaluated. Diclofenac and estrogens were completely
degraded after only 5–25 min even with a very low VP activity (10 U l−1). High degradation percentages (80%) were achieved for sulfamethoxazole and naproxen. Low or undetectable removal yields
were observed for citalopram (up to 18%), fluoxetine (lower than 10%) and carbamazepine (not degraded). 相似文献
9.
Summary. Mammalian testis contains D-aspartic acid (D-Asp), which enhances testosterone production. D-Asp, on other hand, also stimulates
17β-estradiol synthesis in the ovary of some lower vertebrates. We studied boar testis in order to determine if D-Asp intervenes
in 17β-estradiol synthesis in the testis of those mammals which produce significant amounts of estrogens as well as testosterone.
The boar testis contains D-Asp (40 ± 3.6 nmol/g tissue) which, according to immunohistological techniques, is localized mainly
in Leydig cells, and, to a lesser extent, in sustentacular (Sertoli), peritubular and some germ cells. The enzyme P450aromatase
is present in Leydig cells and few germ cells. In vitro experiments showed that the addition of D-Asp to testicular tissue
extracts induced a significant increase of aromatase activity, as evaluated by testosterone conversion into 17β-estradiol.
The enzyme’s Km was not affected by D-Asp (about 25 nM in both control and D-Asp added tests). On the basis of these results we suggest that,
as in the ovary, D-Asp is involved in the local control of aromatase activity of boar testis and, therefore, it intervenes
in the 17β-estradiol production. In the testis, the D-Asp targets are presumably the Leydig cells, which having also a nuclear
estrogen receptor are, in turn, one of the putative targets of the 17β-estradiol that they produce (autocrine effect). 相似文献
10.
Alejandro Lopez-Tobón Efraín Cepeda-Prado Gloria Patricia Cardona-Gómez 《Neurochemical research》2009,34(12):2206-2214
Several studies have linked estrogens with sphingosine kinase (SphK) activity, enzyme responsible of sphingosine-1-phosphate
synthesis (S-1P), however their possible interaction in the nervous system is not documented yet. In the present study, we
developed a glutamate toxicity model in SH-SY5Y cells to evaluate the possible effect of the inhibition of SphK activity on
the protective capability of 17β-estradiol (E2). Glutamate induced cytoskeletal actin changes associated to cytotoxic stress,
significant increase of apoptotic-like nuclear fragmentation, Tau hyperphosphorylation and increase of p25/p35 cleavage. These
effects were prevented by E2 pre-treatment during 24 h. Although the inhibition of SphK did not block this protective effect,
significantly increased Tau hyperphosphorylation by glutamate, in a way that was not reverted by E2. Our results suggest that
the decrease of glutamate-induced Tau hyperphosphorylation by 17β-estradiol requires SphK. 相似文献
11.
Crema LM Vendite D Horn AP Diehl LA Aguiar AP Nunes E Vinade L Fontella FU Salbego C Dalmaz C 《Neurochemical research》2009,34(3):499-507
Glutamate is an excitatory neurotransmitter involved in neuronal plasticity and neurotoxicity. Chronic stress produces several
physiological changes on the spinal cord, many of them presenting sex-specific differences, which probably involve glutamatergic
system alterations. The aim of the present study was to verify possible effects of exposure to chronic restraint stress and
17β-estradiol replacement on [3H]-glutamate release and uptake in spinal cord synaptosomes of ovariectomized (OVX) rats. Female rats were subjected to OVX,
and half of the animals received estradiol replacement. Animals were subdivided in controls and chronically stressed. Restraint
stress or estradiol had no effect on [3H]-glutamate release. The chronic restraint stress promoted a decrease and 17β-estradiol induced an increase on [3H]-glutamate uptake, but the uptake observed in the restraint stress +17β-estradiol group was similar to control. Furthermore,
17β-estradiol treatment caused a significant increase in the immunocontent of the three glutamate transporters present in
spinal cord. Restraint stress had no effect on the expression of these transporters, but prevented the 17β-estradiol effect.
We suggest that changes in the glutamatergic system are likely to take part in the mechanisms involved in spinal cord plasticity
following repeated stress exposure, and that 17β-estradiol levels may affect chronic stress effects in this structure. 相似文献
12.
Sánchez JC López-Zapata DF Francis L De Los Reyes L 《Cellular and molecular neurobiology》2011,31(4):619-627
The Na+/Ca2+ exchanger (NCX) is an important bidirectional transporter of calcium in neurons and has been shown to be involved in neuroprotection.
Calcium can activate a number of cascades that can result in apoptosis and cell death, and NCX is a key factor in regulating
the cytoplasmic concentration of this ion. 17-β-estradiol and insulin-like growth factor 1 (IGF-1) are known neuroprotective
hormones with interacting mechanisms and effects on intracellular calcium; however, their relationship with the NCX has not
been explored. In this article, the effects of these two hormones on neuronal NCX were tested using the whole-cell patch clamp
technique on rat primary culture neurons. Both 17-β-estradiol and IGF-1 produced an increase in the NCX-mediated inward current
and a decrease in the NCX-mediated outward current. However, the IGF-1 effect was lower than that of 17-β-estradiol, and the
effect of both agents together was greater than the sum of each agent alone. Neither of the agents affected the pattern of
regulation by extracellular or intrapipette calcium. Inhibitors of the IGF-1 and 17-β-estradiol receptors and inhibitors of
the main signaling pathways failed to change the observed effects, indicating that these actions were not mediated by the
classical receptors of these hormones. These effects on the NCX could be a mechanism explaining the neuroprotective actions
of 17-β-estradiol and IGF-1, and these findings could help researchers to understand the role of the NCX in neuroprotection. 相似文献
13.
Lewis JB Lapp CA Schafer TE Wataha JC Randol TM Schuster GS 《In vitro cellular & developmental biology. Animal》2000,36(5):320-326
Summary Increasing concerns over the effects of environmental estrogens on wildlife and humans have highlighted the need for screening
systems to assess potentially estrogenic effects of test compounds. As a result, in vitro screening methods such as cell proliferation
assays using the estrogen-responsive human breast cancer cell line, MCF-7, have been developed. The present study describes
an alternative in vitro approach for the assessment of such xenoestrogens, based on estrogenic rescue of MCF-7 cells from
antiestrogen-induced cytotoxicity. This method measures the ability of various estrogenic compounds to compete with a known
estrogen-receptor-mediated antihormonal drug, 4-hydroxytamoxifen, using the 1-[4,5-dimethylthiazol-2-yl]-3,5-diphenylformazan
(MTT) assay to assess mitochondrial activity. Because 4-hydroxytamoxifen treatment of cells results in a dramatic decrease
in mitochondrial dehydrogenase activity which is directly related to their estrogen-receptor content, inhibition of this effect
with estrogenic compounds represents an estrogen-receptor interaction, or estrogenic rescue. The estrogenic compounds tested
include a weak xenoestrogen, bisphernol A (BPA), and two biological estrogens, 17α- and 17β-estradiol. Competitive inhibition
of 4-hydroxytamoxifen-induced cytotoxicity by BPA was compared to that of the biological estrogens. The results indicate that
the biological estrogens can successfully compete with the antiestrogen in a dose-dependent manner. In addition, the assay
is sensitive enough to detect estrogenic rescue by even the very weak xenoestrogen, BPA, albeit at high BPA concentrations.
This simple in vitro method could be used as an alternative or second-line screen for potential xenoestrogens. 相似文献
14.
Samantaray S Smith JA Das A Matzelle DD Varma AK Ray SK Banik NL 《Neurochemical research》2011,36(10):1809-1816
Spinal cord injury (SCI), depending on the severity of injury, leads to neurological dysfunction and paralysis. Methylprednisolone,
the only currently available therapy renders limited protection in SCI. Therefore, other therapeutic agents must be tested
to maximize neuroprotection and functional recovery. Previous data from our laboratory indicate that estrogen (17β-estradiol)
at a high dose may attenuate multiple damaging pathways involved in SCI and improve locomotor outcome. Since use of high dose
estrogen may have detrimental side effects and therefore may never be used in the clinic, the current study investigated the
efficacy of this steroid hormone at very low doses in SCI. In particular, we tested the impact of dosing (1–10 μg/kg), mode
of delivery (intravenous vs. osmotic pump), and delay in estrogen application (15 min–4 h post-SCI) on microgliosis and neuronal
death in acute SCI in rats. Treatment with 17β-estradiol (1–10 μg/kg) significantly reduced microglial activation and also
attenuated apoptosis of neurons compared to untreated SCI animals. The attenuation of cell death and inflammation by estrogen
was observed regardless of mode and time of delivery following injury. These findings suggest estrogen as a potential agent
for the treatment of individuals with SCI. 相似文献
15.
Kazunori Takano Akihiro Takemura Mitsuru Furihata Teruyuki Nakanishi Akihiko Hara 《Environmental Biology of Fishes》1991,30(1-2):39-48
Synopsis Changes in serum steroid hormones were studied during the reproductive cycle of a viviparous rockfish,Sebastiscus marmoratus. Serum levels of estradiol-17β (E2) and testosterone (T) were moderately high throughout the spawning period from December until February (E2), and until post-spawning in April (T). Serum progesterone (prog) fluctuated but remained low throughout the annual reproductive
cycle; 17α,20β-dihydroxy-4-pregnen-3-one (17α, 20β-diOHprog), on the other hand, was relatively high during the spawning period.
During the spawning period, 7 of 12 females reared under laboratory conditions spawned twice at 10-to 16-day intervals. Histological
observations indicated that oocytes developed gradually during gestation of the preceding brood and; after parturition, developed
more quickly towards the end of vitellogenesis and subsequent fertilization. In repeat spawners, E2 and female-specific serum proteins remained high several days after the first parturition, then gradually decreased. Prog
showed no significant changes over the period. The 17α, 20β-diOHprog, however, was low immediately after parturition, then
rapidly increased, remained elevated during the middle of the period and then decreased. These results indicate that E2 is involved in vitellogenesis, and 17α, 20β-diOHprog may have some important roles in gestation in the multiple spawnerS. marmoratus. 相似文献
16.
Paula Klevjer-Anderson Gertrude Case Buehring 《In vitro cellular & developmental biology. Plant》1980,16(6):491-501
Summary The individual effects of seven hormones on the in vitro growth rate of different classifications of human mammary epithelium
were compared. Hormones used were: 17β-estradiol, estriol, progesterone, hydrocortisone, testosterone, prolactin, and growth
hormone. Cell cultures included three established breast cell lines and primary monolayer cultures established form breast
fluids and excised mammary tissue from 40 women and 4 men. Specimens comprised three classifications: normal, nonmalignant
atypical, and malignant. Growth was quantitated in situ and expressed as population doubling time. Principal findings were:
(a) estrogens, prolactin, and growth hormone stimulated growth of normal cells more frequently than growth of malignant cells,
whereas testosterone and hydrocortisone stimulated growth of malignant cells more frequently than growth of normal cells;
(b) cells cultured from nonmalignant atypias generally showed hormone response profiles intermediate between those of normal
and malignant cells; (c) progesterone stimulated the growth of cells from malignant specimens but not the growth of cells
from normal and nonmalignant atypical samples.
This research was supported by NIAID Research Training Grant 5-TO1-A1-00332-06. 相似文献
17.
Nuclear magnetic resonance (NMR) spectroscopy is a useful biophysical technique to study the ligand–protein interaction. In
this report, we have used bacterially produced ERβ and its domains for studying the functional analysis of ligand–protein
interaction. Briefly, ERβ and its transactivation domain (TAD) and ligand binding domain (LBD) were subcloned and overexpressed
using a prokaryotic expression system. The recombinant proteins were purified using Ni+2-IDA affinity chromatography and analyzed by NMR. Purified ERβ and TAD show similar conformation in the absence or presence
of 17β-estradiol. However, LBD shows altered conformation in the presence of 17β-estradiol. These findings suggest that ERβ
produced in bacteria exhibits a conformation such that its LBD remains masked and consequently it binds less to 17β-estradiol.
Such study may help to develop the therapeutic approaches for controlling the estradiol-mediated gene expression in hormone
dependent diseases. 相似文献
18.
19.
Abeer M. Al-Ghananeem Ashraf A. Traboulsi Lewis W. Dittert Anwar A. Hussain 《AAPS PharmSciTech》2002,3(1):40-47
The utility of the nasal route for the systemic delivery of 17β-estradiol was studied using watersoluble prodrugs of 17β-estradiol.
This delivery method was examined to determine if it will result in preferential delivery to the brain. Several alkyl prodrugs
of 17β-estradiol were prepared and their physicochemical properties were determined. In vitro hydrolysis rate constants in
buffer, rat plasma, and rat brain homogenate were determined by high-performance liquid chromatography. In vivo nasal experiments
were carried out on rats. Levels of 17β-estradiol in plasma and cerebral spinal fluid (CSF) were determined with radioimunoassay
using a gamma counter. The study revealed that the aqueous solubilities of the prodrugs were several orders of magnitude greater
than 17β-estradiol with relatively fast in vitro conversion in rat plasma. Absorption was fast following nasal delivery of
the prodrugs with high bioavailability. CSF 17β-estradiol concentration was higher following nasal delivery of the prodrugs
compared to an equivalent intravenous dose. It was determined that water-soluble prodrugs of 17β-estradiol can be administered
nasally. These prodrugs are capable of producing high levels of estradiol in the CSF and as a result may have a significant
value in the treatment of Alzheimer's disease.
Published: March 25, 2002. 相似文献
20.
He F Tai F Zhang Y Zhang X 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2012,198(5):347-362
Aggression in socially monogamous mandarin vole (Microtus mandarinus) was observed after castration. Levels of serum sex hormones and their central receptors were also measured using enzyme-linked
immunosorbent assay and immunohistochemistry methods. The data indicate that adult males showed higher levels of aggression
after castration. However, castration significantly reduced levels of serum testosterone, and the number of androgen receptor
immunoreactive neurons in the anterior hypothalamus, bed nucleus of the stria terminalis, medial amygdaloid nucleus (P < 0.01) and lateral septal nucleus (P < 0.05). In addition, levels of estrogen receptor β in the anterior hypothalamus and medial amygdaloid nucleus (P < 0.05), bed nucleus of the stria terminalis and lateral septal nucleus (P < 0.01) declined to varying degrees at weekly intervals. In contrast, serum 17β-estradiol concentrations were up-regulated
by castration and castration did not change levels of estrogen receptor α in the medial amygdaloid nucleus and lateral septal
nucleus, but increased it in the anterior hypothalamus 3 weeks after castration (P < 0.05). We suggest that higher levels of aggression induced by castration may be independent of serum testosterone and androgen
receptors, and may be associated with high serum 17β-estradiol concentrations, stable estrogen receptor α immunoreactive neurons
in some brain regions and the relative ratio of the two estrogen receptors. 相似文献