scholarly journals Pulmonary and Cardiorenal Cyclooxygenase-1 (COX-1), -2 (COX-2), and Microsomal Prostaglandin E Synthase-1 (mPGES-1) and -2 (mPGES-2) Expression in a Hypertension Model

2007 ◽  
Vol 2007 ◽  
pp. 1-8 ◽  
Author(s):  
Zaher A. Radi ◽  
Robert Ostroski

Hypertensive mice that express the human renin and angiotensinogen genes are used as a model for human hypertension because they develop hypertension secondary to increased renin-angiotensin system activity. Our study investigated the cellular localization and distribution of COX-1, COX-2, mPGES-1, and mPGES-2 in organ tissues from a mouse model of human hypertension. Male (n=15) and female (n=15) double transgenic mice (h-Ang 204/1 h-Ren 9) were used in the study. Lung, kidney, and heart tissues were obtained from mice at necropsy and fixed in 10%neutral buffered formalin followed by embedding in paraffin wax. Cut sections were stained immunohistochemically with antibodies to COX-1, COX-2, mPGES-1, and mPGES-2 and analyzed by light microscopy. Renal expression of COX-1 was the highest in the distal convoluted tubules, cortical collecting ducts, and medullary collecting ducts; while proximal convoluted tubules lacked COX-1 expression. Bronchial and bronchiolar epithelial cells, alveolar macrophages, and cardiac vascular endothelial cells also had strong COX-1 expression, with other renal, pulmonary, or cardiac microanatomic locations having mild-to-moderate expression. mPGES-2 expression was strong in the bronchial and bronchiolar epithelial cells, mild to moderate in various renal microanatomic locations, and absent in cardiac tissues. COX-2 expression was strong in the proximal and distal convoluted tubules, alveolar macrophages, and bronchial and bronchiolar epithelial cells. Marked mPGES-1 was present only in bronchial and bronchiolar epithelial cells; while mild-to-moderate expression was present in other pulmonary, renal, or cardiac microanatomic locations. Expression of these molecules was similar between males and females. Our work suggests that in hypertensive mice, there are (a) significant microanatomic variations in the pulmonary, renal, and cardiac distribution and cellular localization of COX-1, COX-2, mPGES-1, and mPGES-2, and (b) no differences in expression between genders.

2001 ◽  
Vol 69 (8) ◽  
pp. 5056-5063 ◽  
Author(s):  
Tae Il Kim ◽  
Yong Chan Lee ◽  
Kwang Hyoung Lee ◽  
Jae Ho Han ◽  
Chae Yoon Chon ◽  
...  

ABSTRACT Helicobacter pylori and nonsteroidal anti-inflammatory drugs (NSAIDs) are two well-known important causative factors of gastric damage. While H. pylori increases apoptosis and the proliferation of gastric epithelial cells and is an important factor in peptic ulcer and gastric cancer, NSAIDs induce cell apoptosis and have antineoplastic effects. We investigated the effects of NSAIDs (a nonselective cyclooxygenase [COX] inhibitor [indomethacin] and a selective COX-2 inhibitor [NS-398]) on the apoptosis and proliferation of gastric epithelial cells and gastric inflammation inH. pylori-infected mice. C57BL/6 mice were sacrificed 8 weeks after H. pylori SS1 inoculation. Indomethacin (2 mg/kg) or NS-398 (10 mg/kg) was administered subcutaneously once daily for 10 days before sacrifice. The following were assessed: gastric inflammatory activity, gastric COX protein expression by Western blotting; gastric prostaglandin E2 levels by enzyme immunoassay, apoptosis by terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling, and cell proliferation by Ki67 immunostaining. Compared to the controls, H. pylori infection and/or NSAID treatment increased COX-1 and COX-2 protein expression. Gastric prostaglandin E2 levels, apoptotic index, cell proliferation index, neutrophil activity, and the degree of chronic inflammation were all increased by H. pylori infection, and these effects were significantly decreased by indomethacin treatment. However, NS-398 treatment after H. pylori infection did not induce a significant reduction, although it did result in a tendency to decrease. These results show that NSAIDs can reverse the increased apoptosis and proliferation of epithelial cells and inflammatory activity in the stomachs of H. pylori-infected mice and that, like COX-2 activation, COX-1 induction contributes to the change of gastric mucosal cell turnover and inflammation induced by H. pylori infection.


2012 ◽  
Vol 81 (1) ◽  
pp. 373-380
Author(s):  
Mari Kogiso ◽  
Tsutomu Shinohara ◽  
C. Kathleen Dorey ◽  
Yoshimi Shibata

Intranasal vaccination stimulates formation of cyclooxygenases (COX) and release of prostaglandin E2(PGE2) by lung cells, including alveolar macrophages. PGE2plays complex pro- or anti-inflammatory roles in facilitating mucosal immune responses, but the relative contributions of COX-1 and COX-2 remain unclear. Previously, we found thatMycobacterium bovisBCG, a human tuberculosis vaccine, stimulated increased release of PGE2by macrophages activatedin vitro; in contrast, intranasal BCG activated no PGE2release in the lungs, because COX-1 and COX-2 in alveolar macrophages were subcellularly dissociated from the nuclear envelope (NE) and catalytically inactive. This study tested the hypothesis that intranasal administration of BCG with cholera toxin (CT), a mucosal vaccine component, would shift the inactive, NE-dissociated COX-1/COX-2 to active, NE-associated forms. The results showed increased PGE2release in the lungs and NE-associated COX-2 in the majority of COX-2+macrophages. These COX-2+macrophages were the primary source of PGE2release in the lungs, since there was only slight enhancement of NE-associated COX-1 and there was no change in COX-1/COX-2 levels in alveolar epithelial cells following treatment with CT and/or BCG. To further understand the effect of CT, we investigated the timing of BCG versus CT administration forin vivoandin vitromacrophage activations. When CT followed BCG treatment, macrophagesin vitrohad elevated COX-2-mediated PGE2release, but macrophagesin vivoexhibited less activation of NE-associated COX-2. Our results indicate that inclusion of CT in the intranasal BCG vaccination enhances COX-2-mediated PGE2release by alveolar macrophages and further suggest that the effect of CTin vivois mediated by other lung cells.


Endocrinology ◽  
2002 ◽  
Vol 143 (6) ◽  
pp. 2410-2419 ◽  
Author(s):  
Michael Lazarus ◽  
Craig J. Munday ◽  
Naomi Eguchi ◽  
Shigeko Matsumoto ◽  
Gary J. Killian ◽  
...  

Abstract We investigated the tissue distribution and cellular localization of microsomal PGE synthase-1 (mPGES-1) and cyclooxygenase (COX)-1 and -2 in the male mouse reproductive organs. Northern blotting revealed that the mPGES-1 mRNA was expressed intensely in the epididymis and weakly in the lung, spleen, skin, kidney, colon, and brain. In the male reproductive tract, the expression of mPGES-1 increased from the testis to the cauda epididymis and was highest in the vas deferens when examined by Northern blotting, RT-PCR, and Western blotting. By immunohistochemistry, mPGES-1 was detected in Leydig cells of the testis and in epithelial cells of the epididymis, vas deferens, and seminal vesicles. In addition, the caput and cauda regions of the epididymis and the vas deferens in this order showed a progressive increase in the expression of COX-1 mRNA and immunoreactivity, whereas COX-2 was dominantly expressed in the vas deferens. COX-1 was localized in epithelial cells of the caput, corpus and cauda epididymis and of the vas deferens, and COX-2 was evident in epithelial cells of the distal cauda epididymis and vas deferens. These results show that mPGES-1 is expressed coordinately with COX-1 and COX-2 and is involved in PGE2 production in male genital organs.


1994 ◽  
Vol 266 (5) ◽  
pp. F823-F828 ◽  
Author(s):  
Y. Sugimoto ◽  
T. Namba ◽  
R. Shigemoto ◽  
M. Negishi ◽  
A. Ichikawa ◽  
...  

Distribution of the mRNAs for three subtypes of prostaglandin E (PGE) receptors in the mouse kidney was investigated by in situ hybridization. The mRNA for EP1 subtype, which is coupled to Ca2+ mobilization, was specifically localized to the collecting ducts from the cortex to the papilla. The mRNA for EP2 subtype, which is linked to stimulation of adenylate cyclase, was localized to the glomeruli. The mRNA for EP3 subtype, which is coupled to inhibition of adenylate cyclase, was located densely in the tubules in the outer medulla and in the distal tubules in the cortex. These results exhibit distinct cellular localization of three subtypes of PGE receptor in the kidney and suggest that PGE2 exerts multiple functions via these subtypes expressed in different segments of the nephron.


Zygote ◽  
2005 ◽  
Vol 13 (2) ◽  
pp. 103-108 ◽  
Author(s):  
Hui-Ning Tan ◽  
Ying Liu ◽  
Hong-Lu Diao ◽  
Zeng-Ming Yang

Prostaglandin E2 (PGE2) is shown to be essential for female reproduction. Cyclooxygenase (COX) is a rate-limiting enzyme in prostaglandin synthesis from arachidonic acid and exists in two isoforms: COX-1 and COX-2. Prostaglandin E synthase (PGES) is a terminal prostanoid synthase and can catalyse the isomerization of the COX product PGH2 to PGE2, including microsomal PGES-1 (mPGES-1), cytosolic PGES (cPGES) and mPGES-2. This study examined the protein expression of COX-1, COX-2, mPGES-1, cPGES and mPGES-2 in preimplantation mouse embryos by immunohistochemistry. Embryos at different stages collected from oviducts or uteri were transferred into a flushed oviduct of non-pregnant mice. The oviducts containing embryos were paraffin-embedded and processed for immunostaining. COX-1 immunostaining was at a basal level in zygotes and a low level at the 2-cell stage, reaching a high level from the 4-cell to blastocyst stage. COX-2 immunostaining was at a low level at the zygote stage and was maintained at a high level from the 2-cell to blastocyst stages. A low level of mPGES-1 immunostaining was observed from the zygote to 8-cell stages. The signal for mPGES-1 immunostaining became stronger at the morula stage and was strongly seen at the blastocyst stage. cPGES immunostaining was strongly observed in zygotes, 2-cell and 8-cell embryos. There was a slight decrease in cPGES immunostaining at the 4-cell, morula and blastocyst stages. mPGES-2 immunostaining was at a low level from the zygote to morula stages and at a high level at the blastocyst stage. We found that the COX-1, COX-2, mPGES-1, cPGES and mPGES-2 protein signals were all at a high level at the blastocyst stage. PGE2 produced during the preimplantation development may play roles during embryo transport and implantation.


1997 ◽  
Vol 272 (3) ◽  
pp. G681-G687 ◽  
Author(s):  
K. Morimoto ◽  
Y. Sugimoto ◽  
M. Katsuyama ◽  
H. Oida ◽  
K. Tsuboi ◽  
...  

Regional and cellular distribution of mRNAs for prostaglandin E (PGE) receptor subtypes was investigated in the mouse gastrointestinal tract by in situ hybridization. Strong signals for EP1 transcripts were detected in cells of the muscularis mucosae layer, especially in the body of the stomach. Intense signals for EP3 transcripts were detected in neurons of the myenteric ganglia throughout the tract. Moderate EP3 mRNA expression was also observed in fundic gland epithelial cells, except for surface mucous cells in the stomach. Expression of EP4 mRNA was moderate in surface epithelial cells of the corpus and in glands from the surface to the base of the antrum. Strong EP4 signals were observed in the epithelium in the duodenum, jejunum, and ileum. In the ileum, signals were only observed in the upper part of the villi. However, no or weak signals for EP2 transcripts were detected. These findings suggest that PGE2 modulates various gastric or intestinal functions via at least three different PGE receptors.


2007 ◽  
Vol 23 (4) ◽  
pp. E8 ◽  
Author(s):  
Christina Pfister ◽  
Rainer Ritz ◽  
Heike Pfrommer ◽  
Antje Bornemann ◽  
Marcos S. Tatagiba ◽  
...  

Object The current treatment for recurrent or malignant meningiomas with adjuvant therapies has not been satisfactory, and there is an intense interest in evaluating new molecular markers to act as therapeutic targets. Enzymes of the arachidonic acid (AA) cascade such as cyclooxygenase (COX)–2 or 5-lipoxygenase (5-LO) are upregulated in a number of epithelial tumors, but to date there are hardly any data about the expression of these markers in meningiomas. To find possible targets for chemotherapeutic intervention, the authors evaluated the expression of AA derivatives at different molecular levels in meningiomas. Methods One hundred and twenty-four meningioma surgical specimens and normal human cortical tissue samples were immunohistochemically and cytochemically stained for COX-2, COX-1, 5-LO, and prostaglandin E receptor 4 (PTGER4). In addition, Western blot and polymerase chain reaction (PCR) analyses were performed to detect the presence of eicosanoids in vivo and in vitro. Results Sixty (63%) of 95 benign meningiomas, 21 (88%) of 24 atypical meningiomas, all five malignant meningiomas, and all normal human cortex samples displayed high COX-2 immunoreactivity. All cultured specimens and IOMM-Lee cells stained positive for COX-2, COX-1, 5-LO, and PTGER4. The PCR analysis demonstrated no changes in eicosanoid expression among meningiomas of different World Health Organization grades and in normal human cortical and dura mater tissue. Conclusions Eicosanoid derivatives COX-1, COX-2, 5-LO, and PTGER4 enzymes show a high universal expression in meningiomas but are not upregulated in normal human cortex and dura tissue. This finding of the ubiquitous presence of these enzymes in meningiomas offers an excellent baseline for testing upcoming chemotherapeutic treatments.


1996 ◽  
Vol 270 (3) ◽  
pp. G393-G400 ◽  
Author(s):  
C. S. Williams ◽  
R. N. DuBois

Prostaglandin endoperoxide synthase-1 [prostaglandin G/H synthase-1 (PGHS-1)] and PGHS-2 are key enzymes in the conversion of arachidonic acid to prostaglandins and other eicosanoids. We refer to these isoforms as cyclooxygenase-1 (COX-1) and COX-2 in this review. This brief review focuses on recent developments in the study of these enzymes. Alterations in the expression levels of COX-2 result in distinct phenotypic changes in intestinal epithelial cells. Overexpression of COX-2 in intestinal epithelial cells results in increased adhesion to extracellular matrix proteins and inhibition of apoptosis. Disruption of the COX-2 gene in mice results in renal dysplasia, cardiac fibrosis, and defects in the ovary. Interestingly, disruption of the COX-1 gene results in distinct phenotypic changes different from those observed for COX-2. COX-1 null mice survive well, have no gastric pathology, and show less indomethacin-induced gastric ulceration than wild-type mice. These two closely related enzymes must have distinct functions in the organisms, since lack of their expression causes distinct phenotypic changes for each respective isoform.


2005 ◽  
Vol 53 (11) ◽  
pp. 1391-1401 ◽  
Author(s):  
William E. Ackerman IV ◽  
John M. Robinson ◽  
Douglas A. Kniss

Cytokine-induced prostaglandin (PG)E2 synthesis requires increased expression of cyclooxygenase-2 (COX-2) in human WISH epithelial cells. Recently, an inducible downstream PGE synthase (microsomal PGE synthase-1, mPGES-1) has been implicated in this inflammatory pathway. We evaluated cooperation between COX-2 and mPGES-1 as a potential mechanism for induced PGE2 production in WISH cells. Cytokine stimulation led to increased expression of both enzymes. Selective pharmacological inhibition of these enzymes demonstrated that induced PGE2 release occurred through a dominant COX-2/mPGES-1 pathway. Unexpectedly, immunofluorescent microscopy revealed that the expression of these enzymes was not tightly coordinated among cells after cytokine challenge. Within cells expressing high levels of both mPGES-1 and COX-2, immunolabeling of high-resolution semithin cryosections revealed that COX-2 and mPGES-1 were largely segregated to distinct regions within continuous intracellular membranes. Using biochemical means, it was further revealed that the majority of mPGES-1 resided within detergent-insoluble membrane fractions, whereas COX-2 was found only in detergent-soluble fractions. We conclude that although mPGES-1 and COX-2 show transcriptional and functional coordination in cytokine-induced PGE2 synthesis, complementary morphological and biochemical data suggest that a majority of intracellular mPGES-1 and COX-2 are segregated to discrete lipid microdomains in WISH epithelial cells.


1999 ◽  
Vol 8 (6) ◽  
pp. 287-294 ◽  
Author(s):  
Pravit Akarasereenont ◽  
Kitirat Techatrisak ◽  
Sirikul Chotewuttakorn ◽  
Athiwat Thaworn

Prostaglandins (PGS) have numerous cardiovascular and inflammatory effects. Cyclooxygenase (COX), which exists as COX-1 and COX-2 isoforms, is the first enzyme in the pathway in which arachidonic acid is converted to PGs. Prostaglandin E2 (PGE2) exerts a variety of biological activities for the maintenance of local homeostasis in the body. Elucidation of PGE2 involvement in the signalling molecules such as COX could lead to potential therapeutic interventions. Here, we have investigated the effects of PGE2 on the induction of COX-2 in human umbilical vein endothelial cells (HUVEC) treated with interleukin-1β (IL-1β 1 ng/ml). COX activity was measured by the production of 6-keto-PGF1α, PGE2, PGF2α and thromboxane B2 (TXB2) in the presence of exogenous arachidonic acids (10 μM for 10 min) using enzyme immunoassay (EIA). COX-1 and COX-2 protein was measured by immunoblotting using specific antibody. Untreated HUVEC contained only COX-1 protein while IL-1β treated HUVEC contained COX-1 and COX-2 protein. PGE2 (3 μM for 24 h) did not affect on COX activity and protein in untreated HUVEC. Interestingly, PGE2 (3 μM for 24 h) can inhibit COX-2 protein, but not COX-1 protein, expressed in HUVEC treated with IL1 β. This inhibition was reversed by coincubation with forskolin (100 μM). The increased COX activity in HUVEC treated with IL-1β was also inhibited by PGE2 (0.03, 0.3 and 3 μM for 24 h) in a dose-dependent manner. Similarly, forskolin (10, 50 or 100 μM) can also reverse the inhibition of PGE2 on increased COX activity in IL-1β treated HUVEC. The results suggested that (i) PGE2 can initiate negative feedback regulation in the induction of COX-2 elicited by IL-1β in endothelial cells, (ii) the inhibition of PGE2 on COX-2 protein and activity in IL-1β treated HUVEC is mediated by cAMP and (iii) the therapeutic use of PGE2 in the condition which COX-2 has been involved may have different roles.


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