Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of indomethacin, an inhibitor of prostaglandin synthetase, on lymphocyte blast transformation induced by T- or B-cell activators has been studied. Simultaneously adding indomethacin (0.03-0.3 x 10(-6) M final concentration) and concanavalin A to mouse spleen cell cultures, led to an enhancement of 3H-thymidine uptake, whereas 30 x 10(-6) M indomethacin inhibited this uptake. The stimulation induced by indomethacin was higher when this drug was present in the cultures before the addition of the mitogen. Neither the optimal concanavalin A concentration nor the day on which the maximum of 3H-thymidine uptake occurred were altered by indomethacin. Activation of B lymphocytes induced by bacterial lipopolysaccharide was inhibited by indomethacin at all concentrations tested. However, indomethacin similarly blocked the prostaglandin synthesis as well in lipopolysaccharide- or concanavalin A-stimulated lymphocyte cultures. Indomethacin enhanced the one-way mixed lymphocyte reaction. No significant effect of indomethacin was found on cell-mediated cytotoxicity of 51Cr labeled targets. The results are discussed in terms of differential sensitivity of B and T lymphocytes to this anti-inflammatory drug.
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PMID:Effect of indomethacin on in vitro T- and B-cell activation and cell-mediated lysis. 31 6

To identify genes induced during macrophage activation, a cDNA library was prepared from cultures of the RAW 264.7 mouse macrophage cell line that had been treated with conditioned medium from mitogen-stimulated spleen cells, and the cDNA library was screened by differential plaque hybridization. Eleven cDNA clones, designated CRG-1 through CRG-11, corresponding to mRNA species inducible in RAW 264.7 cells by the spleen cell conditioned medium, were isolated. Inductions were not blocked by cycloheximide. All of the mRNAs were inducible by gamma interferon, and some were also inducible by alpha and beta interferons, by lipopolysaccharide, by phorbol 12-myristate 13-acetate, and by the calcium ionophore A23187. Sequencing of the cDNAs revealed that CRG-1, CRG-3, and CRG-5 are cDNAs of recently identified transcription factors IRF-1, zif/268, and LRF-1 respectively. As previously reported, CRG-2 and CRG-10 (MIG) encode new members of the platelet factor 4 family of cytokines. CRG-6 corresponds to a new member of a family of interferon-inducible genes clustered on mouse chromosome 1, CRG-9 corresponds to a prostaglandin synthase homolog, CRG-8 corresponds to beta 2-microglobulin, and CRG-4 corresponds to metallothionein II. CRG-11 contains sequences of a truncated L1Md repetitive element as well as nonrepetitive sequences. The nonrepetitive sequence of CRG-11 as well as the sequences of CRG-7 are not closely related to published sequences. The CRG genes and proteins are of interest because of their involvement in macrophage activation, because of their roles as mediators of the effects of gamma interferon and other pleiotropic agents, and because of their usefulness as tools for studying the signal pathways through which gamma interferon and other inducers exert their effects on gene and protein expression.
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PMID:A collection of mRNA species that are inducible in the RAW 264.7 mouse macrophage cell line by gamma interferon and other agents. 137 86

Cyclooxygenase (Cox), also known as prostaglandin (PG) H synthase (EC 1.14.99.1), catalyzes the rate-limiting step in the formation of inflammatory PGs. A major regulatory step in PG biosynthesis is at the level of Cox: growth factors, cytokines, and tumor promoters induce Cox activity. We have cloned the second form of the Cox gene (Cox-2) from human umbilical vein endothelial cells (HUVEC). The cDNA encodes a polypeptide of 604 amino acids that is 61% identical to the previously isolated human Cox-1 polypeptide. In vitro translation of the human (h)Cox-2 transcript in rabbit reticulocyte lysates resulted in the synthesis of a 70-kDa protein that is immunoprecipitated by antiserum to ovine Cox. Expression of the hCox-2 open reading frame in Cos-7 monkey kidney cells results in the elaboration of cyclooxygenase activity. hCox-2 cDNA hybridizes to a 4.5-kilobase mRNA species in HUVEC, whereas the hCox-1 cDNA hybridizes to 3- and 5.3-kilobase species. Both Cox-1 and Cox-2 mRNAs are expressed in HUVEC, vascular smooth muscle cells, monocytes, and fibroblasts. Cox-2 mRNA was preferentially induced by phorbol 12-myristate 13-acetate and lipopolysaccharide in human endothelial cells and monocytes. Together, these data demonstrate that the Cox enzyme is encoded by at least two genes that are expressed and differentially regulated in a variety of cell types. High-level induction of the hCox-2 transcript in mesenchymal-derived inflammatory cells suggests a role in inflammatory conditions.
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PMID:Human cyclooxygenase-2 cDNA. 138 Jan 56

The inhibition of prostaglandin generation by AD-1590 was investigated in the rabbit brain in-vivo. AD-1590 (0.4 mg kg-1 i.v.) markedly prevented both the increases in body temperature and PGE2 level in cerebrospinal fluid (CSF) caused by i.v. injection of lipopolysaccharide. On the other hand, 2,4-dinitrophenol (20 mg kg-1 i.v.)-induced hyperthermia, which was not affected by AD-1590, was not accompanied by an increase in PGE2 level in CSF. When injected intracerebroventricularly, AD-1590 dose-dependently inhibited the hyperthermia caused by arachidonic acid given by the same route; its ED50 was 1.6 micrograms compared with about 35 micrograms for indomethacin. From these results, it is suggested that AD-1590 is more active than indomethacin in suppressing prostaglandin synthetase in rabbit brain.
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PMID:Inhibition of prostaglandin generation in the rabbit brain in-vivo by AD-1590, a non-steroidal anti-inflammatory agent with potent antipyretic activity. 286 98

The protective effect of some novel nonsteroidal anti-inflammatory agents has been studied on the endotoxin (lipopolysaccharide B) shock induced mortality in mice and biochemical changes in rats. All the three compounds included in this report, namely isoxicam, fentiazac and ketoprofen have been found to produce significant protection against the endotoxin mortality in mice. Isoxicam and fentiazac have been found effective in antagonizing some of the biochemical changes induced by endotoxin in rats. On the other hand isoxicam and ketoprofen exacerbated the increase in serum aminotransferases induced by endotoxin. It is suggested that mechanisms other than the prostaglandin synthetase inhibition may be involved in the protective effect of these drugs.
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PMID:Effect of some new prostaglandin synthetase inhibitors on the endotoxin induced mortality and biochemical changes in experimental animals. 313 34

Leishmania tropica in BALB/c mice causes a fatal infection accompanied by the development of multiple metastatic lesions. Spleen cells from these mice were shown to have depressed proliferative responses to concanavalin A (Con A), phytohemagglutinin (PHA), and lipopolysaccharide (LPS). Coinciding with this immunodepression was the development of a cell population capable of suppressing normal spleen cell responses to Con A. This suppressor cell activity was first observed at 6 wk and was present throughout the remainder of the infection. At 12 wk the suppressor cells could be removed by Sephadex G-10 passage or carbonyl iron treatment; however, Sephadex G-10 passage could not reverse the suppression at 18 wk. Indomethacin, a prostaglandin synthetase inhibitor, was found to abrogate the activity of the adherent suppressor cell, suggesting that prostaglandin production may be involved in the immunosuppression seen in these mice. In addition, Sephadex G-10 passage and indomethacin were found to markedly augment spleen cell responses to leishmanial antigen, indicating that the adherent suppressor cell is capable of regulating specific immunologic responses.
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PMID:Experimental cutaneous leishmaniasis. I. Nonspecific immunodepression in BALB/c mice infected with Leishmania tropica. 645 74

Spleen cells of diabetes-prone BB Wistar rats were found to generate excessively low proliferative responses, and interleukin 2 (IL-2) levels in response to T-dependent mitogens. This abnormality was not due solely to abnormal T cell numbers since: (a) addition of BB spleen cells of BB splenic macrophages to normal major histocompatibility complex (MHC)-matched Wistar Furth (WF) spleen cells resulted in severe suppression of concanavalin A (Con A)-, phytohemagglutinin (PHA)-, and pokeweed mitogen (PWM)-mediated proliferation, and IL-2 production; (b) macrophage depletion from BB spleen cells, but not B cell or T cell depletion, removed completely the suppressive effects of BB cells on WF cells; (c) macrophage depletion greatly enhanced the response of BB lymphocytes to T-dependent mitogens. Although suppressor macrophages could also be found in the spleen of WF control rats they were present in much smaller numbers than in the spleen of BB rats. The suppressive effect of BB macrophages was partially reduced by addition of the prostaglandin synthetase inhibitor indomethacin to cultures. Furthermore, indomethacin (but not catalase or PMA) considerably augmented IL-2 secretion of Con A-stimulated BB spleen cells, but had little effect on WF spleen cells. In contrast, prostaglandins E1 and E2 (PGE1 and PGE2) suppressed IL-2 production. While IL-2 secretion was severely depressed in BB rats unstimulated and lipopolysaccharide (LPS)-stimulated IL-1 secretion by splenic macrophages was normal. BB macrophages did not inactivate IL-2. Low IL-2 production and macrophage-mediated suppression were features of all BB rats tested.
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PMID:Immune dysfunction in diabetes-prone BB rats. Interleukin 2 production and other mitogen-induced responses are suppressed by activated macrophages. 660 15

The products of arachidonic acid oxygenations by resident mouse peritoneal macrophages have been found to depend upon the nature of the stimulus. For example, soluble membrane-mediated inflammatory stimuli such as phorbol myristate acetate and lipopolysaccharide stimulated the formation of prostaglandin E2 via the cyclooxygenase pathway. In contrast, zymosan, a particulate, phagocytozable inflammatory mediator stimulated leukotrienes C4 and B4 synthesis via the lipoxygenase pathway in addition to stimulating prostaglandin E2 synthesis. Thus, the release of leukotrienes is not necessarily linked to the release of prostaglandins in a cell that has the enzymatic capability of producing both mediators. This suggests that the prostaglandin synthetase system can obtain substrate arachidonic acid from a source different from that for leukotriene synthesis.
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PMID:Evidence for two sources of arachidonic acid for oxidative metabolism by mouse peritoneal macrophages. 679 9

The intraperitoneal administration of lipopolysaccharide from Salmonella typhimurium (1 mg/kg) caused a fall in the rat colonic temperature of about 2 degrees C at an ambient temperature of 22 +/- 3 degrees C. The hypothermia induced by the lipopolysaccharide was abated in a dose-dependent manner by the administration of indomethacin. Other inhibitors of prostaglandin synthetase such as aspirin, flufenamic acid, and phenylbutazone had effects similar to those of indomethacin. When various prostaglandins were injected intracerebroventricularly, only prostaglandin D2 caused a dose-dependent fall in the colonic temperature at doses between 1.2 and 6 nmol/kg. Microinjection of prostaglandin D2 into the preoptic area caused hypothermia of about 1 degree C. However, injection of prostaglandin D2 into the posterior hypothalamus had little effect on the colonic temperature. The hypothermia caused by prostaglandin D2 was not abated by the administration of indomethacin. The amount of prostaglandin D2 increased significantly in the preoptic/hypothalamic region of rat brain 1 hr after the intraperitoneal administration of the lipopolysaccharide, whereas such increase was not observed in rats pretreated with indomethacin. The in vitro incubation of the preoptic/hypothalamic slices with the lipopolysaccharide also increased the amount of prostaglandin D2. These results suggest that the intraperitoneal administration of the lipopolysaccharide induces the release of prostaglandin D2 in the preoptic/hypothalamic area of rat brain and that the latter compound is involved in the hypothermic response of rats to the lipopolysaccharide.
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PMID:Role of prostaglandin D2 in the hypothermia of rats caused by bacterial lipopolysaccharide. 696 2

There exist two distinct isozymes of prostaglandin-endoperoxide synthase (PES). PES-2 mRNA is synergistically induced by lipopolysaccharide (LPS) and 12-O-tetradecanoylphorbol-13-acetate (TPA) in bovine arterial endothelial cells. On the other hand, PES-1 mRNA is constitutively expressed under these conditions. Therefore, the promoter activities of the human genes for PES-1 and -2 in bovine arterial endothelial cells were examined. The 5'-flanking region of the human PES-2 gene (nucleotides -327 to +59) showed promoter activity inducible by LPS and TPA using transient transfection analysis, whereas that of the PES-1 gene (nucleotides -1010 to +69) showed constitutive promoter activity. Destruction of both consensus sequences for the nuclear factor responsible for the interleukin-6 expression (NF-IL6) site (nucleotides -132 to -124) and the cyclic AMP response element (CRE) (nucleotides -59 to -53) of the human PES-2 gene markedly reduced the promoter activity (25%) of the PES-2 gene after combined treatment with LPS and TPA, although single destruction of the NF-IL6 site or the CRE slightly reduced the promoter activity (60 or 90%, respectively). Moreover, cotransfection experiments showed that a trans-acting factor, CCAAT enhancer binding protein delta (C/EBP delta), which binds to both the NF-IL6 site and the CRE, increased the promoter activity of the PES-2 gene mainly through the CRE. C/EBP delta mRNA was rapidly induced by LPS. Collectively, these results suggest that transcription of the PES-2 gene in vascular endothelial cells is regulated through combination of the NF-IL6 site and the CRE and that C/EBP delta functions as one of the trans-acting factors.
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PMID:Transcriptional regulation of human prostaglandin-endoperoxide synthase-2 gene by lipopolysaccharide and phorbol ester in vascular endothelial cells. Involvement of both nuclear factor for interleukin-6 expression site and cAMP response element. 755 24


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