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Neuroscience Research Institute, State University of New York, Old Westbury, NY 11568;
Mind/Body Medical Institute, Beth Israel Deaconess Medical Center, Boston, MA 02215;
Unité de Neuroendocrinologie et Physiopathologie Neuronale, Institut National de la Santé et de la Recherche Médicale, U422, Lille, France;
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Laboratoire d’Endocrinologie des Annélides, Centre National de la Recherche Scientifique, Université des Sciences et Technologies de Lille, Villeneuve d’Ascq, France;
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Institut National de la Santé et de la Recherche Médicale, U416, Institut Pasteur de Lille, Lille, France; and
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Division of Cardiothoracic Surgery, Department of Surgery, State University of New York, Stony Brook, NY 11794
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Abstract |
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 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
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-estradiol had no effect.
17ß-estradiol conjugated to BSA (E2-BSA) also stimulated
NO release, suggesting mediation by a membrane surface receptor.
Tamoxifen, an estrogen receptor inhibitor, antagonized the action of
both 17ß-estradiol and E2-BSA, whereas ICI 182,780, a
selective inhibitor of the nuclear estrogen receptor, had no effect. We
further showed, using a dual emission microfluorometry in a
calcium-free medium, that the 17ß-estradiol-stimulated release of
monocyte NO was dependent on the initial stimulation of intracellular
calcium transients in a tamoxifen-sensitive process. Leeching out the
intracellular calcium stores abolished the effect of 17ß-estradiol on
NO release. RT-PCR analysis of RNA obtained from the cells revealed a
strong estrogen receptor- amplification signal and a weak ß
signal. Taken together, a physiological dose of estrogen acutely
stimulates NO release from human monocytes via the activation of an
estrogen surface receptor that is coupled to increases in intracellular
calcium. |
Introduction |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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Given these recent findings, we examined human peripheral monocytes to determine whether they exhibited an estrogen surface receptor (ESR)3 that when stimulated released constitutive NO synthase (cNOS)-derived NO in a calcium- and tamoxifen-sensitive manner. We demonstrate for the first time that human peripheral monocytes exhibit an ESR whose NO release is calcium-dependent, tamoxifen-sensitive, and ICI 182,780-insensitive. Thus, the NO produced as a result of estrogen stimulation may, in part, be the process whereby this hormone causes cellular immunosuppression as well as other immune actions.
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Materials and Methods |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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Human peripheral monocytes were obtained from the Long Island Blood Services (Melville, NY). The cells were isolated via the Accurate (Westbury, NY) monocyte kit and washed as previously described in great detail (26, 27, 28).
NO release from the incubated monocytes (107 cells/chamber) was measured directly using an NO-specific amperometric probe (World Precision Instruments, Sarasota, FL) as described by Stefano and colleagues (26, 29). Briefly, the cells were placed in a superfusion chamber in 2 ml PBS. A micromanipulator (Zeiss-Eppendorff, Oberkochen, Germany) attached to the stage of an inverted microscope (Nikon Diaphot, Melville, NY) was employed to position the amperometric probe 15 µm above the cell surface. The system was calibrated daily using different concentrations of the nitrosothiol donor S-nitroso-N-acetyl-DL-penicillamine (Sigma, St. Louis, MO; S-acetyl-DL-penicillamine (SAP) was used as a negative control) to generate a standard curve. Baseline levels of NO release were determined by evaluation of NO release in PBS. Cells were stimulated with the respective ligand, and the concentration of NO gas in solution was measured in real time with the DUO 18 computer data acquisition system (World Precision Instruments). The amperometric probe was allowed to equilibrate for at least 12 h in PBS before being transferred to the superfusion chamber containing the cells, and manipulation of the cells was performed only with glass instruments. Each experiment was repeated four times. Each experiment was simultaneously performed with a control from the same tissue source (vehicle alone) to exclude experimental drift in NO release unrelated to the study drugs.
To evaluate NO release, the cells were exposed to a concentration
gradient of the various ligands. If an antagonist or a NOS inhibitor
was used, it was administered 2 min before that of the various estrogen
ligands. The NOS inhibitor,
N
-nitro-L-arginine
methyl ester (L-NAME) was used in these
studies.
Data were evaluated by Student’s t test. Data acquisition was by the computer-interfaced DUO-18 software (World Precision Instruments). The experimental values were then transferred to Sigma-Plot and -Stat (Jandel, San Rafael, CA) for graphic representation and evaluation. Data gatherers were unaware of the experimental treatments.
Ligands
The monocytes were stimulated with various concentrations of
17ß-estradiol (10-13 to
10-7 M) or 17ß-estradiol conjugated to BSA
(E2-BSA) (10-13 to
10-7 M of 17ß-estradiol). They were also
stimulated with 17-estradiol (10-9 M)
(n = 4), tamoxifen (10-9 M), or
ICI 182,780 (10-9 to 10-5
M), estrogen receptor antagonists (n = 4), or tamoxifen
(10-9 M) plus 17ß-estradiol
(10-9M) (n = 4), or tamoxifen
(10-9 M) plus E2-BSA
(10-13 to 10-7 M of
17ß-estradiol), E2-BSA
(10-9 M) (n = 4) or ICI 182,780
(10-9 M) plus E2-BSA
(10-9 M) (n = 4). Tamoxifen and
ICI 182,780 were added to the milieu 2 min before 17ß-estradiol or
E2-BSA. To determine that there was no
dissociation between 17ß-estradiol and BSA, an RIA kit optimized for
the direct quantitative determination of very low concentrations of
17ß-estradiol (ICN Pharmaceuticals, Costa Mesa, CA) was used.
17ß-estradiol was measured in the cytosolic fraction of monocytes
(107 cells/ml) treated with
10-9 to 10-7 M
E2-BSA. After washing, the cells were put through
a freeze-thawing cycle (three times), cellular debris was pelleted
(12,000 rpm 15 min), and the cytosolic material evaluated for free
estradiol. Estradiol was not detected in the cytosol. The assay
sensitivity was 0.2 pg/tube.
Intracellular calcium levels monitored by calcium imaging
Monocytes were allowed to adhere in chamber slides (Nunc,
Naperville, IN) using PBS (30) supplemented with 10% FCS
at 37°C in a 5% CO2 atmosphere
(31). To promote rapid adherence, the chambers were rinsed
with 1% BSA. The cells were left under these conditions for 2 h
before experimentation commenced. We estimate that at the end of this
period we lost 
50% of the cells due to the introduction of DMSO,
which causes the cells to break their adherence. The cells were
diluted, equaling 100 monocytes per chamber slide chamber.
Intracellular calcium levels were measured by dual emission
microfluorometry using the fluorescent dye fura 2-AM. Cells were loaded
with the fluorescent ion indicator as follows. They were washed twice
in the incubation medium minus calcium, balanced with sucrose to
maintain osmolarity (31), and then incubated with 5 µM
fura 2-AM for 30 min at room temperature. In experiments designed to
leach the tissues of their calcium, the tissues were maintained in the
same medium with more frequent changes over a 3-h period. The nonionic
and nondenaturing detergent Pluronic F-127 helped disperse
acetoxymethyl esters of fura-2 in the loading buffer. Cells were
washed twice with PBS, and then test drugs were added. The
intracellular calcium concentration
([Ca2+]i) was calculated
from the fluorescence ratio (340 and 380 nm excitation and 510 nm
emission wavelength) according to the equation (see Refs.
32 and 33): [Ca2+] =
(R - Rmin)
Kd ß/(Rmax -
R), where R, fluorescence ratio recorded from the cell;
Rmin, fluorescence ratio of fura 2-free acid
recorded in absence of Ca2+;
Rmax, fluorescence ratio of fura 2-free acid
recorded in saturating concentration of Ca2+;
Kd, calcium dissociation constant of
the dye; and ß, the ratio of the fluorescence of fura 2-free acid in
the Ca2+-free form to the
Ca2+-saturated form recorded at the wavelength
used in the denominator of the ratio. Images were acquired every
0.4 s with an image-processing system COMPIX C-640 SIMCA (Compix,
Mars, PA) and an inverted Nikon microscope. Experiments were conducted
at room temperature in PBS without calcium/magnesium. When the
respective receptor antagonists were used, they were administered 2 min
before the respective agonist. The antagonists did not stimulate
[Ca2+]i at the test
concentrations. Furthermore, under control conditions, the cells
exhibited a low level
[Ca2+]i in the 0–2.1 nM
range.
A two-way ANOVA was used for statistical analysis on the peak [Ca]i time, 7 s after agonist exposure to the cells. Each experiment was simultaneously performed with up to eight cells. The mean value was combined with the mean value taken from four other replicates. The SEM represents the variation of the mean of the means.
All drugs were purchased from Sigma, except ICI 182,780 that was kindly provided by Zeneca Pharmaceuticals (Costa Mesa, CA).
RT-PCR analysis
Human monocytes were obtained from the Pasteur Institute (Lille, France). The cells were isolated using Magnetic Cell Sorting MicroBeads (MACS) as described by the manufacturer (Miltenyi Biotec, Heidelburg, Germany). CD14 MicroBeads were used to enrich monocytes/macrophages from peripheral blood. After MACS separation, monocytes purity is >99%.
Total RNA from monocytes was extracted using Trizol (Life
Technologies/BRL, Strasbourg, France). A total of 3 µg RNA was
reverse transcribed into cDNA using random hexamers and Moloney murine
leukemia virus RT (Life Technologies/BRL), as previously described
(34). One-sixth of the first strand synthesis reaction was
amplified for 40 cycles using 1U Taq polymerase and 100 pmol
of each forward and reverse primer. The cycling parameters were 94°C
for 90 s, 65°C for 90 s, and 72°C for 120 s.
Negative control RT-PCR reactions were performed by omitting reverse
transcriptase or RNA from the reaction mixture. In both pairs, the
priming sites were separated by an intron, thus preventing
amplification of any contaminating genomic DNA (data not shown). For
the ER amplification, the primer pair (25 mer) was designed to
amplify a 281-bp cDNA fragment (residues 83–177, according to Ref.
(35)). For the ER ß amplification, the primer pair (25
mer) generated a 265-bp cDNA product (residues 381–469, according to
Ref. (36)). As an internal control, GAPDH mRNA was also
amplified using a primer pair (37) design to amplify a
470-bp cDNA (residues 36–192, according to Ref. (38). The
PCR products were subcloned-using TA cloning vector systems
(Stratagene, Paris, France) and sequenced to verify the specificity of
the amplification.
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Results |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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NO release was measured in real time using a NO-specific
amperometric probe following stimulation of the monocytes either with
17ß-estradiol or E2-BSA (Fig. 1
, inset). Normally, monocytes release
low levels of cNOS-derived NO (0–1 nM range) (26).
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and inset). This
17ß-estradiol-stimulated process can be inhibited by first
exposing the tissue to tamoxifen, an estrogen receptor blocker
(Fig. 2). Increasing concentrations
of 17ß-estradiol (10-11 to
10-7 M) resulted in a dose-dependent increase in
NO release with a maximal effect observed at
10-9 M (Fig. 1). This increase peaked before the
2-min observation period upon 17ß-estradiol exposure to the monocytes
(Figs. 1 and 2). Addition of 10-11 M
17ß-estradiol failed to stimulate a significant increase in NO
release.
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-estradiol (10-9 M) did not stimulate any
release from the monocytes (data not shown). Tamoxifen
(10-9 M), an estradiol receptor inhibitor,
significantly diminished (p < 0.005)
17ß-estradiol-stimulated endothelial NO release (Fig. 2).
17ß-estradiol acts as a surface receptor.
17ß-estradiol appears to stimulate NO release by acting on the
membrane surface, not on an intracellular receptor.
E2-BSA (10-9 M), which
does not penetrate the cellular membrane due to its size, also
stimulates monocyte NO release within 2 min of its application in a
tamoxifen-sensitive process (Figs. 1 and 2). As with 17ß-estradiol,
the E2-BSA-stimulated NO release is
dose-dependent (Fig. 1). Stimulation of either tissue with
10-11 M E2-BSA failed to
stimulate a significant increase in NO release. The median effective
concentration (EC50) for
E2-BSA-stimulated NO release is 5 x
10-10 M. It appears in these cells that
E2-BSA is as potent as 17ß-estradiol in
stimulating NO release (Figs. 1 and 2). In this regard, it is important
to note that testosterone and progesterone were without effect
(Fig. 1).
To further establish that this indeed is the case, L-NAME
(100 µM), a NOS inhibitor, blocked the NO-stimulating activities of
17ß-estradiol (Table I). To further
establish the specificity of this phenomenon, we attempted to inhibit
the estrogen-stimulated NO release using ICI 182,780, a nuclear
estrogen receptor antagonist (39, 40). Supporting the cell
membrane estrogen receptor location for monocyte NO release coupling,
ICI 182,780 (10-8 and
10-7 M) was without effect when exposed to
E2 BSA, whereas, at higher concentrations, it did
block E2-BSA (Fig. 3).
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In a few recent reports from our laboratory, we demonstrated that
morphine, anandamide, and estrogen stimulated cNOS-derived NO release
from endothelial cells, which was dependent on intracellular calcium
transients (31, 41). In this regard, we performed the same
experiments with the monocytes in a calcium-free medium. In real time,
17ß-estradiol (10-9 M) stimulated a rapid
intracellular calcium transient within 6 s of its exposure to
these cells (Fig. 4). This event could be
blocked by prior tamoxifen (10-9 M) exposure but
not by ICI 182,780 (Fig. 4). The EC50 value for
17ß-estradiol is 6 x 10-10 M, and the
IC50 value for tamoxifen is 9 x
10-10 M.
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). Given the fact that cNOS requires
Ca2+, we determined whether these events were
linked. Over a 3-h period, we changed the
Ca2+-free incubation medium of the cells five
times in an attempt to leach out the intracellular calcium stores
(31). After the 3-h incubation, 17ß-estradiol
(10-9 M) increased [Ca]i
to 2.2 ± 0.7 nM ± SEM (Fig. 4f). This level is
substantially lower than those previously described under nonleaching
conditions (Fig. 4a). Furthermore, NO release was barely
above background in the Ca2+-leached monocytes
following 17-ß-estradiol (NO 2.3 + 0.8 nM, compared with a peak value
of 13.6 ± 2.4) exposure, strongly suggesting that intracellular
Ca2+ levels regulate cNOS activity and that
Ca2+ originates from the estrogen receptor’s
coupling to [Ca]i.
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and ß gene expression in human monocytes
To determine which estrogen receptor genes were expressed in
monocytes, we performed RT-PCR analysis of RNA extracted from three
independent blood samples. The presence of GAPDH transcripts was also
assessed as a control. As shown in Fig. 6, single bands of 281 bp (ER ), 265
bp (ER ß), and 470 bp (GAPDH) were detected. The sizes of the PCR
amplification products corresponded to the sizes predicted from the
genomic sequences. ER amplification signal was observed, as was ER
ß, in monocytes; however, the ER material exhibited a higher
density reading (+69% over ER ß, determined by Gel Pro Density
Analysis (Media Cybernetics, Silver Spring, MD)). It was apparent that
both genes could be expressed within the same cell type. The nature of
the PCR products was further assessed after subcloning and sequencing
of the specific bands. cDNA sequences obtained for human breast cell
lines (MCF7 and MDA MB231) and monocytes were identical and were
identified as the sequence of ER and ß receptor.
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Discussion |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
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-estradiol action. The fact that
E2-BSA, an impermeable cell membrane estradiol
analogue, also stimulates NO release and ICI 182,780 cannot block its
action, indicates that this receptor is located on the surface of the
cNOS-containing cells. Furthermore, 17ß-estradiol and
E2-BSA-stimulated NO release is inhibited by
L-NAME, a NOS inhibitor, indicating that the effect of the
agonists on NO release is mediated by coupling the membrane estrogen
receptor to cNOS. Additionally, the estrogen-stimulated release of
monocyte cNOS-derived NO is dependent on the initial stimulation of
intracellular calcium transients, supporting the cNOS activation by
estrogen, since it is calcium-dependent. Taken together, the study not
only demonstrates a monocyte ESR but its NO coupling via intracellular
calcium transients’ pathways. This finding might explain some
beneficial actions of estrogens, for instance, acute effects observed
in premenopausal women for not developing atherosclerosis
(42, 43, 44, 45, 46, 47). Considering other studies, estrogen acutely stimulates ecNOS and [Ca2+]i in fetal pulmonary artery endothelium within minutes of its exposure (40). It was concluded that the action of estrogen occurred via a nuclear receptor because they fully inhibited the 17ß-estradiol-stimulated NOS activity with either tamoxifen or ICI-182,780 (40). Recently, Chen et al. (48) reported that both tamoxifen and ICI-182,780 also antagonized a nongenomic estradiol-stimulated NO release from ovine endothelial cells. The present work extends the results of these studies by demonstrating that on human monocytes, estrogen acutely stimulates NO release by acting on a surface estrogen receptor leading to cNOS activation via the stimulation of intracellular calcium transient.
We, however, demonstrate that this ESR is ICI-182,780-insensitive at
the tamoxifen-antagonizing concentration. In this regard, Razandi et
al. (49) showed that the binding of 17ß-estradiol on the
membrane ER was competitively inhibited by micromolar ICI-182,780. In
the present study, we succeeded in inhibiting the estradiol-stimulated
NO release by a nanomolar concentration of tamoxifen, but we failed in
inhibiting this process with 10-9 to
10-7 M ICI-182,780. This result, at first
glance, appears to contradict the two earlier cited studies (48, 49). However, Chen et al. (48) and Razandi et al.
(49) used 10-5 M and
10-6 M concentrations of ICI-182,780 to inhibit
nongenomic effects of estradiol. Razandi et al. (49) also
reported that the Kd of the membrane
ER is in the 0.2 nM range. Therefore, we surmise that the use of
micromolar concentrations of ICI-182,780 is abnormally high for the
receptor Kd and may have nonspecific
actions, whereas at 10-9 M, tamoxifen exerts its
action and is in the Kd ER receptor
range. Supporting this hypothesis are unpublished data from our
laboratory, demonstrating that the use of 10-5 M
tamoxifen or 10-5 M ICI-182,780 reduced by 23%
and 20%, respectively, morphine-stimulated NO release from human
endothelial cells (29). This indicates that at high doses
these drugs become less selective. Taking this into account, ER and
ER ß cDNA-expressing cells presented both membrane and nuclear
estrogen receptors (49). Here, we also note via RT-PCR
that monocytes express both ER and ß materials with an apparent
higher level of the former. However, human granulocytes only express ER
and exhibit both NO release and calcium transients in response to
17ß-estradiol and E2-BSA in a
tamoxifen-sensitive and ICI-182,780-insensitive process (G. B.
Stefano, unpublished observations), suggesting that ER is the ESR
mediating these phenomena in monocytes.
Furthermore, tamoxifen, although it is often considered as an antagonist of the nuclear estrogen receptor, is also able to antagonize the effect of estradiol on its membrane receptor as shown by our group (50) and by others (51, 52). In this regard, Benten et al. (53) found in splenic T cells isolated from mice that 17ß-estradiol stimulated [Ca2+]i in a tamoxifen-insensitive manner. This finding supports our present observations regarding an estrogen surface receptor, since the authors reached the same conclusion using E2-BSA as well. The lack of tamoxifen-sensitivity in their studies and its efficacy in ours may simply be due to species and/or cell variations.
The structure of the membrane ERs is unknown, but since single cDNA and RNA are capable of producing both membrane and nuclear receptors, the membrane ER must be very similar to the classical nuclear ER (49). Posttranslational modification of some ER protein must occur to ensure targeting to the membrane, a phenomenon that may also explain the ICI 182,780 insensitivity at low concentrations. Interestingly, Razandi et al. (49) have shown that membrane ER were G protein linked. Thus, one possible mechanism for the acute estradiol-induced NO release in monocytes could be that 17ß-estradiol activates the G protein pathway leading to intracellular calcium stores mobilization and then to cNOS activation and NO release.
In another recent study, we demonstrated that 17ß-estradiol stimulates NO release from human internal thoracic artery fragments and from cultured arterial endothelial cells by acting on an ESR, given that E2-BSA was as potent as 17ß-estradiol in stimulating NO release by both types of endothelial cells (41). In this study, ICI-182,780 did not block the cNOS stimulatory action of estradiol as did tamoxifen. Estradiol short-term stimulating action, i.e., NO release, via a specific ESR on arterial endothelial cells and monocytes is supported by other recent studies that demonstrate a vasodilatory role for estrogen involving NO occurs quickly (42, 54, 55, 56). Beside its short-term stimulating action, estradiol can have a long-term action via a nuclear receptor on NO release from endothelia (39, 57). Estradiol can indeed increase ecNOS expression within 8 h after its application on human vein endothelial cells, via a nuclear receptor-mediated system, and this action can be inhibited by the selective nuclear estrogen receptor antagonist, ICI-182,780 (15). The presence of two left-half palindromic sites of an estrogen receptor-binding element on the human ecNOS gene supports a potential receptor-mediated effect of estrogen on gene expression (57).
In regard to monocytes, estrogen down-regulates immunocyte functions, i.e. chemotaxis and phagocytosis (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13). This action can also be initiated by inhibiting the adhesion potential of the immunocytes and endothelial lining of the vasculature (3, 14, 15, 16). Furthermore, in accordance with our present observations, monocytes express estrogen receptor mRNA as well as an estrogen receptor binding site (20, 21, 22, 23, 24, 25).
Taken together, estrogen’s ability to stimulate cNOS-derived NO is significant since NO is also considered as an important inhibitory agent that diminishes immunocyte adhesion and the vascular endothelium’s capability to adhere immunocytes as well as down-regulating various immunocytes both before and after proinflammatory events (58, 59). In this regard, estrogen is acting in parallel with endogenous morphine and the endocannabinoid anandamide (58, 59).
At first glance, it may appear that we have a redundant immunovascular down-regulating process. However, we believe that each signaling system performs this common function, i.e., cNOS-derived NO release, under different circumstances. Morphine, given its long latency before increases in its levels are detected, arises after trauma/inflammation to down-regulate these processes in neural and immune tissues (59, 60, 61). Anandamide, by being part of the always present arachidonate and eicosanoid signaling processes, serves to maintain tonal NO in vascular tissues (62). We surmise that estrogen, since testosterone or progesterone don’t exert this NO generating action, provides an extra-degree of immunocyte and vascular down-regulation in females. This is most probably due to both the immune and vascular trauma associated with cyclic reproduction activities, i.e., endometrial buildup, when a high degree of vascular and immune activities are occurring. Given the high degree of proliferative growth capacity during estrogen peak levels in this cycle, NO may function to enhance down-regulation of the immune system to allow for these changes. In this regard, it is not difficult to understand the reports documenting various cancers with blocking estrogen actions and, conversely, reports documenting its anti-cancer protective actions (63).
Our work establishes that a physiological dose of estrogen acutely stimulates NO release from human monocytes via the activation of an ESR and increases intracellular Ca2+ transients. This finding promises to open up new areas of investigation concerning estrogen-associated biomedical phenomena.
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Footnotes |
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2 Address correspondence and reprint requests to Dr. G. B. Stefano, Neuroscience Research Institute, State University of New York, College at Old Westbury, P.O. Box 210, Old Westbury, NY 11568-0210. E-mail address:
3 Abbreviations used in this paper: ESR, estrogen surface receptor; cNOS, constitutive NO synthase; ecNOS, endothelial cNOS; L-NAME, N-nitro-L-arginine methyl ester; E2-BSA, 17ß-estradiol conjugated to BSA; ER, estrogen receptor.
Received for publication March 9, 1999. Accepted for publication July 23, 1999.
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References |
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TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
can be induced from mononuclear phagocytes by HIV-1 binding to CD4 receptor. J. Virol. 63:4404. mediates the nongenomic activation of endothlelial nitric oxide synthase by estrogen. J. Clin. Invest. 103:401.[Medline]
and ERß expressed in Chinese hamster ovary cells. Mol. Endocrinol. 13:307.This article has been cited by other articles:
|
|
 |
|
  R. Panchanathan, H. Shen, M. G. Bupp, K. A. Gould, and D. Choubey Female and Male Sex Hormones Differentially Regulate Expression of Ifi202, an Interferon-Inducible Lupus Susceptibility Gene within the Nba2 Interval J. Immunol., December 1, 2009; 183(11): 7031 - 7038. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Osorio, D. L. Bonilla, A. G. Peniche, P. C. Melby, and B. L. Travi Pregnancy enhances the innate immune response in experimental cutaneous leishmaniasis through hormone-modulated nitric oxide production J. Leukoc. Biol., June 1, 2008; 83(6): 1413 - 1422. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Subramanian and C. Shaha Up-Regulation of Bcl-2 through ERK Phosphorylation Is Associated with Human Macrophage Survival in an Estrogen Microenvironment J. Immunol., August 15, 2007; 179(4): 2330 - 2338. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. H. Straub The Complex Role of Estrogens in Inflammation Endocr. Rev., August 1, 2007; 28(5): 521 - 574. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Bouman, M. J. Heineman, and M. M. Faas Sex hormones and the immune response in humans Hum. Reprod. Update, July 1, 2005; 11(4): 411 - 423. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Xia and T. L. Krukoff Estrogen Induces Nitric Oxide Production via Activation of Constitutive Nitric Oxide Synthases in Human Neuroblastoma Cells Endocrinology, October 1, 2004; 145(10): 4550 - 4557. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Willis, J.M. Morris, V. Danis, and E.D.M. Gallery Cytokine production by peripheral blood monocytes during the normal human ovulatory menstrual cycle Hum. Reprod., June 1, 2003; 18(6): 1173 - 1178. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. B. Stefano, P. Cadet, K. Mantione, J. J. Cho, D. Jones, and W. Zhu Estrogen Signaling at the Cell Surface Coupled to Nitric Oxide Release in Mytilus edulis Nervous System Endocrinology, April 1, 2003; 144(4): 1234 - 1240. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Alvarez, C. Hermenegildo, A. C. Issekutz, J. V. Esplugues, and M.-J. Sanz Estrogens Inhibit Angiotensin II-Induced Leukocyte-Endothelial Cell Interactions In Vivo via Rapid Endothelial Nitric Oxide Synthase and Cyclooxygenase Activation Circ. Res., December 13, 2002; 91(12): 1142 - 1150. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Maccarrone, M. Bari, N. Battista, and A. Finazzi-Agro Estrogen stimulates arachidonoylethanolamide release from human endothelial cells and platelet activation Blood, December 1, 2002; 100(12): 4040 - 4048. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. Vasudevan, S. Ogawa, and D. Pfaff Estrogen and Thyroid Hormone Receptor Interactions: Physiological Flexibility by Molecular Specificity Physiol Rev, October 1, 2002; 82(4): 923 - 944. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. M. McNeill, C. Zhang, F. Z. Stanczyk, S. P. Duckles, and D. N. Krause Estrogen Increases Endothelial Nitric Oxide Synthase via Estrogen Receptors in Rat Cerebral Blood Vessels: Effect Preserved After Concurrent Treatment With Medroxyprogesterone Acetate or Progesterone Stroke, June 1, 2002; 33(6): 1685 - 1691. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Sakihama, S. Nakamura, and H. Yamasaki Nitric Oxide Production Mediated by Nitrate Reductase in the Green Alga Chlamydomonas reinhardtii: an Alternative NO Production Pathway in Photosynthetic Organisms Plant Cell Physiol., March 1, 2002; 43(3): 290 - 297. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Pfeilschifter, R. Koditz, M. Pfohl, and H. Schatz Changes in Proinflammatory Cytokine Activity after Menopause Endocr. Rev., February 1, 2002; 23(1): 90 - 119. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. Vasudevan, L.-M. Kow, and D. W. Pfaff Early membrane estrogenic effects required for full expression of slower genomic actions in a nerve cell line PNAS, September 19, 2001; (2001) 221449798. [Abstract] [Full Text] [PDF]
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W. P. M. Benten, C. Stephan, M. Lieberherr, and F. Wunderlich Estradiol Signaling via Sequestrable Surface Receptors Endocrinology, April 1, 2001; 142(4): 1669 - 1677. [Abstract] [Full Text]
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G. B. Stefano, P. Cadet, C. Breton, Y. Goumon, V. Prevot, J. P. Dessaint, J.-C. Beauvillain, A. S. Roumier, I. Welters, and M. Salzet Estradiol-stimulated nitric oxide release in human granulocytes is dependent on intracellular calcium transients: evidence of a cell surface estrogen receptor Blood, June 15, 2000; 95(12): 3951 - 3958. [Abstract] [Full Text] [PDF]
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 S. Kahlert, S. Nuedling, M. van Eickels, H. Vetter, R. Meyer, and C. Grohe Estrogen Receptor alpha Rapidly Activates the IGF-1 Receptor Pathway J. Biol. Chem., June 9, 2000; 275(24): 18447 - 18453. [Abstract] [Full Text] [PDF]
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N. Vasudevan, L.-M. Kow, and D. W. Pfaff Early membrane estrogenic effects required for full expression of slower genomic actions in a nerve cell line PNAS, October 9, 2001; 98(21): 12267 - 12271. [Abstract] [Full Text] [PDF]
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