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)

Both chlamydial and human heat shock protein 60s (HSP 60), which colocalize in human atheroma, may contribute to inflammation during atherogenesis. We tested the hypothesis that chlamydial or human HSP 60 activates human endothelial cells (ECs), smooth muscle cells (SMCs), and monocyte-derived macrophages. We examined the expression of adhesion molecules such as endothelial-leukocyte adhesion molecule-1 (E-selectin), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1), and the production of the proinflammatory cytokine interleukin-6 (IL-6). We also tested whether either HSP 60 induces nuclear factor-kappaB (NF-kappaB), which contributes to the gene expression of these molecules. Either chlamydial or human HSP 60 induced E-selectin, ICAM-1, and VCAM-1 expression on ECs similar to levels induced by Escherichia coli lipopolysaccharide (LPS). Each HSP 60 also significantly induced IL-6 production by ECs, SMCs, and macrophages to an extent similar to that induced by E. coli LPS, as assessed by enzyme-linked immunosorbent assay (ELISA). In ECs, either HSP 60 triggered activation of NF-kappaB complexes containing p65 and p50 Rel proteins. Heat treatment abolished all these effects, but did not alter the ability of E. coli LPS to induce these functions. Chlamydial and human HSP 60s therefore activate human vascular cell functions relevant to atherogenesis and lesional complications. These findings help to elucidate the mechanisms by which a chronic asymptomatic chlamydial infection might contribute to the pathophysiology of atheroma.
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PMID:Chlamydial and human heat shock protein 60s activate human vascular endothelium, smooth muscle cells, and macrophages. 1002 66

Selective estrogen receptors modulators (SERMs) are a series of new compounds exerting estrogenic or anti-estrogenic effects in different tissues. 17Beta-estradiol is known to inhibit endothelial vascular cell adhesion molecule (VCAM)-1 expression. We studied the relative effects of the raloxifene analogue LY117018 and of tamoxifen on lipopolysaccharide (LPS)-induced VCAM-1 expression in cultured human saphenous vein endothelial cells (HSVEC) and on HSVEC adhesiveness towards U937 monocytoid cells. We here demonstrate a concentration-dependent inhibitory action on VCAM-1 protein expression both for 17beta-estradiol and LY117018. The action of both compounds was blocked by the pure anti-estrogen ICI 182,780. LY117018 did not antagonize 17beta-estradiol activity. On the contrary, tamoxifen had no effects of his own. Both 17beta-estradiol and LY117018 inhibited HSVEC VCAM-1 expression at the mRNA level, while tamoxifen was ineffective. Finally, 17beta-estradiol and LY117018, but not tamoxifen, inhibited HSVEC adhesiveness towards U937 monocytoid cells induced by LPS stimulation. Therefore, only some SERMs have potential anti-atherogenic actions exerted directly at the vascular level through the regulation of endothelial cell adhesion molecules expression and of endothelial-leukocyte interactions.
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PMID:Selective estrogen receptor modulators: different actions on vascular cell adhesion molecule-1 (VCAM-1) expression in human endothelial cells. 1002 60

Gram-negative septic shock is mediated in part by endotoxin (lipopolysaccharide; LPS), and animal models have shown that blockade of even single adhesion molecules considerably improves survival. Thus interference with the adhesion cascade may provide a useful therapeutic approach in human sepsis. Young healthy men (n = 30) each received a bolus of 4 ng/kg LPS intravenously to study the effects of endotoxemia on adhesion processes in humans and to identify potential targets for pharmacologic intervention. One third of subjects received pretreatment with 1,000 mg aspirin and 1,000 mg paracetamol to study potential antiinflammatory effects of aspirin or effects of antipyresis. Circulating neutrophils dropped by -80% at 67 min after LPS, monocytes by -96% at 90 min, and lymphocytes by -85% at 240 min. L-selectin expression decreased, particularly on monocytes. Circulating (c)E-selectin levels increased by 820%, von Willebrand factor-Ag (vWF), soluble thrombomodulin, circulating (c)P-selectin, circulating intercellular adhesion molecule-1 (cICAM-1), and circulating vascular cell adhesion molecule-1 (cVCAM-1) by a mean of 65 to 98% (p < 0.001 for all), but cL-selectin by only 15%. Urinary excretion of soluble adhesion molecules was negligible. Aspirin had no influence on the LPS-induced changes of adhesion parameters, but paracetamol blunted the relative increase in vWF while having no effects on the other parameters measured. The consistent, profound, and early upregulation of cE-selectin during endotoxemia indicates that cE-selectin may be a better surrogate marker to monitor the activation status of endothelial cells in systemic inflammation than the other markers measured. Although aspirin did not have any antiinflammatory effects in this model, paracetamol lowered the relative increase in vWF.
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PMID:Regulation of adhesion molecules during human endotoxemia. No acute effects of aspirin. 1005 Dec 63

Sequestration of neutrophils and release of histotoxic mediators are considered important for the development of pathologic alterations of the lung defined as adult respiratory distress syndrome. Mechanisms of inflammatory lung injury caused by abdominal sepsis were investigated using the colon ascendens stent peritonitis (CASP) model that closely mimics the human disease. In the CASP model, a continuous leakage of intraluminal bacteria into the peritoneal cavity is induced by implantation of a stent in the ascending colon, generating a septic focus. In contrast to the cecal ligation and puncture model of peritonitis, survival of mice following CASP surgery is dependent on IFN-gamma, but independent of tumor necrosis factor (TNF). Here we show that the systemic inflammation induced by CASP surgery results in a rapid and profound increase of lung vascular permeability that was associated with the activation and recruitment of neutrophils to the lung. Activation of circulating granulocytes was characterized by increased production of serine proteinases and reactive oxygen metabolites, as well as elevated expression of cell surface Mac-1. Expression of MIP-2, KC, MIP-1alpha and E-selectin mRNA in lung was strongly increased within 3 h following CASP surgery, whereas up-regulation of IP-10, MCP-1 and P-selectin was delayed. In contrast, induction of RANTES, LIX, ICAM-1 and VCAM-1 mRNA was weak or not detectable after CASP surgery. Importantly, recruitment of leukocytes to the lung was normal in lipopolysaccharide-resistant mice, and was not affected by antibody neutralization of TNF or the chemokines MIP-2 and KC.
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PMID:Mechanisms of acute inflammatory lung injury induced by abdominal sepsis. 1006 20

The effect of IS-741 (N-[(2-ethylsulfonylamino)-5-trifluoromethyl-3-pyridyl] cyclohexanecarboxamide monohydrate) on a model for pancreatitis has been previously reported. Recent patho-histological observations of remedial tests using rats found that the IS-741 administered group showed a low degree of tissue infiltration by inflammatory cells (polymorphonuclear leukocytes). We therefore examined cell adhesion, which is the first step in tissue infiltration by activated neutrophils, and investigated the effect of IS-741 on cell adhesion between human umbilical vein endothelial cells (HUVEC) and human promyelo-leukemia cell line (HL-60) cells during lipopolysaccharide stimulation in vitro. IS-741 significantly inhibited the adhesion of HL-60 cells to HUVEC. Further investigation of IS-741 on individual cells revealed that IS-741 mainly affected HL-60 cells. Investigation of the inhibitory effect of IS-741 at the molecular level (targeting adhesion molecules) also revealed that IS-741 had no effect on the appearance of endothelial leukocyte adhesion molecule-1 (ELAM-1), intercellular adhesion molecule-1 (ICAM-1) or vascular cell adhesion molecule-1 (VCAM-1) on HUVEC, which supports the theory that IS-741 is mainly effective on HL-60 cells, even at the molecular level. However, the inhibition of adhesion was noticed in experiments in which an anti-ICAM-1 or anti-VCAM-1 antibody was added to the adhesion test system. Therefore, IS-741 is likely to affect adhesion molecules which belong to the beta1 or beta2 integrin family.
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PMID:Effect of IS-741 on cell adhesion between human umbilical vein endothelial cells and HL-60 cells. 1007 29

Interleukin (IL)-10 is known to inhibit the production of proinflammatory cytokines by macrophages suggesting that endogenous IL-10 may act as an antiinflammatory agent. Because endothelial cell adhesion molecules (ECAMs) play a key role in the recruitment of leukocytes into tissue in response to an inflammatory stimulus (i.e., lipopolysaccharide (LPS)) and the following cytokine production, we wished to assess the importance of IL-10 as an endogenous modulator of ECAM expression using IL-10 deficient mice. Constitutive and LPS-stimulated expression of intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1 and E-selectin were measured in wild type C57BL/6 and IL-10 deficient mice with no signs of active enterocolitis, using the dual radiolabeled monoclonal antibody technique. We found that constitutive expression of these ECAMs did not differ between IL-10 deficient and WT mice for all organs tested. However, we demonstrated larger increments in LPS-induced expression of ICAM-1 and VCAM-1 in the vasculature of the small intestine in IL-10 deficient mice compared to WT mice. These findings suggest that endogenous IL-10 does not modulate constitutive or LPS-induced expression of ECAMs in most tissues, however it does appear to play an inhibitory role in LPS-stimulated expression of ICAM-1 and VCAM-1 in the intestinal vasculature.
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PMID:Effects of lipopolysaccharide on endothelial cell adhesion molecule expression in interleukin-10 deficient mice. 1021 66

Although important advances have been made in the development of antibiotics and medical intensive care technology in recent years, systemic response to infection remains a major health problem, with growing incidence and high mortality rates. Here we demonstrate the ability of the antioxidant agent pyrrolidine dithiocarbamate (PDTC) to inhibit the in vivo activation of NF-kappaB in lung and liver tissues, as well as the systemic release of TNF-alpha in lipopolysaccharide (LPS)-treated mice. The in vivo effect of PDTC on NF-kappaB activation in liver tissues involved the inhibition of both LPS-induced I kappaB-alpha degradation and the translocation of the p50 and p65 NF-kappaB subunits to the nucleus. In addition to protecting mice against lethal LPS doses, PDTC curtailed TNF-alpha-induced lethal shock. This effect was observed even after LPS injection, and when PDTC was administered at a time when TNF-alpha was already at maximum levels in serum. PDTC-treated mice survived despite high IL-1beta and IL-6 levels, induction of VCAM-1 and ICAM-1 expression or leukocyte infiltration in tissues known to be associated with LPS-induced shock, indicating that PDTC does not act by modifying these responses. Taken together, these results indicate that PDTC interferes with the production as well as the action of TNF-alpha, and points to a possible approach toward the treatment of septic shock.
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PMID:Pyrrolidine dithiocarbamate protects mice from lethal shock induced by LPS or TNF-alpha. 1038 51

The structural and functional heterogeneity of hepatocytes and non-parenchymal cells across the liver lobule or acinus has been well documented. The geographic distribution and potential for induced expression of adhesion molecules on murine hepatic microvascular cells has not been reported, although these molecules are able to influence the metastatic outcome of intravascular cancer cells. We have postulated that the expression of adhesion molecules on these cells is susceptible to regulation by environmental factors and that these molecules have a zonal distribution across the acinus. To test this hypothesis, we injected C57BL/6 mice with bacterial lipopolysaccharide, 1 microg/g body weight, i.p. At various time points (0-48 h) after stimulation, liver tissue sections were prepared for immunohistochemistry. Confocal microscopy was used to detect the expression of vascular cell adhesion molecule-1 (VCAM-1), E-selectin, intercellular adhesion molecule-1 (ICAM-1) and alpha v integrin. The expression patterns were quantitatively measured by histomorphometry. Under basal conditions, ICAM-1 was weakly expressed in terminal portal veins while minimal VCAM-1 and no E-selectin were detected. Following stimulation with lipopolysaccharide, VCAM-1 and E-selectin were expressed on the endothelium of terminal portal veins and on sinusoidal lining cells with significantly stronger expression in the periportal zone than midzone. VCAM-1 expression peaked at 4 h and decreased gradually by 48 h. E-selectin peaked at 2 h and disappeared by 12 h after stimulation. ICAM-1 expression showed a much stronger and more uniform expression across the acinus with the peak reached by 4 h and sustained for longer than 48 h after lipopolysaccharide administration. The alpha v integrin was not detected under basal conditions or after lipopolysaccharide stimulation. Expression of all these adhesion molecules (ICAM-1, VCAM-1, E-selectin and alpha v integrin) was induced by growth of B16F1 melanoma cells in the peritoneal cavity of the mouse. These results support the hypotheses that expression of microvascular adhesion molecules in the mouse liver is susceptible to regulation by environmental stimuli and has a zonal heterogeneity across the acinus.
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PMID:Murine hepatic microvascular adhesion molecule expression is inducible and has a zonal distribution. 1041 Nov 7

Manipulation of the intracellular redox state has been shown to alter cell activation pathways with resultant changes in cellular function. Previous studies have suggested that thiol oxidation, using the glutathione-depleting agent diethyl maleate (DEM), was able to inhibit endothelial cell activation. We hypothesized that this agent might exert beneficial effects following endotoxemia in the rat, a model in which transendothelial migration of neutrophils is central to the development of hepatocellular injury. Sprague-Dawley rats treated intraperitoneally with lipopolysaccharide (LPS) (200 microg/kg) plus D-galactosamine (GalN) (600 mg/kg) developed hepatocellular necrosis, as evidenced by liver enzyme release and morphological changes. Pretreatment with DEM abrogated this injury in a dose-dependent fashion. Histology revealed reduced neutrophil accumulation in both the parenchyma and sinusoids, consistent with reduced neutrophil sequestration and transendothelial migration. This effect appeared to be related to the ability of DEM to prevent LPS-induced up-regulation of both vascular cell adhesion molecule-1 (VCAM-1) mRNA and intercellular adhesion molecule-1 (ICAM-1) mRNA in the liver, as well as reducing tumor necrosis factor (TNF) mRNA expression. In addition, DEM prevented hepatocyte apoptosis following LPS treatment. The effect was reproduced when TNF was used as an inflammatory stimulus, suggesting a direct protective effect on the hepatocyte. Taken together, these studies show that redox manipulation through thiol oxidation may represent a novel approach to preventing liver necrosis and apoptosis in inflammatory conditions.
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PMID:Redox manipulation using the thiol-oxidizing agent diethyl maleate prevents hepatocellular necrosis and apoptosis in a rodent endotoxemia model. 1046 78

Bacteroides thetaiotaomicron, a Gram-negative anaerobic rod belonging to the Bacteroides fragilis group (BFG), is involved in many systemic and local, most frequently suppurative infections in man. The cell envelope of these rods is composed of two carbohydrate-containing antigens: lipopolysaccharide (LPS) and capsular polysaccharide (CPS). Adhesion molecules ICAM-1, VCAM-1 and E-selectin (ELAM-1) are induced on the endothelial cells by mediators of inflammation. The aim of this study was to assay the ability of B. thetaiotaomicron surface antigens to induce adhesion molecule expression on the endothelial cells. The influence of LPS and CPS on the expression of adhesion molecules on HMEC-1 cell line was examined in an ELISA test. ELISA was performed with monoclonal mouse anti-human: ICAM-1, VCAM-1 and E-selectin antibodies of the IgG class. B. thetaiotaomicron lipopolysaccharides revealed the ability to induce ICAM-1, VCAM-1 and E-selectin expression on the endothelial cells. Their activities were similar, but lower than the activity of Eschericha coli LPS. ICAM-1 was the most stimulated adhesion molecule. The strongest activation by LPS was achieved at the concentrations of 10.0 and 1.0 micrograms/ml. The ability of capsular polysaccharide to induce the expression of adhesion molecules was considerably weaker.
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PMID:Adhesion molecule expression stimulated by Bacteroides thetaiotaomicron cell-surface antigens. 1047 Apr 44


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