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)

We investigate the regulation of plasminogen activator inhibitor-2 (PAI-2) in murine macrophages. PAI-2 mRNA was inducible by bacterial lipopolysaccharide (LPS) in primary cells and macrophage-like cell lines. Evidence is presented for a role for autocrine factors, including cyclooxygenase products but not the cytokines tumor necrosis factor alpha or interferon-beta (IFN-beta). PAI-2 mRNA levels generally varied inversely from those of its target, urokinase-type plasminogen activator (uPA), and the macrophage growth factor CSF-1, which induces uPA, inhibited PAI-2 expression in cells treated subsequently with LPS. Expression of PAI-2 was distinct from that of other LPS-inducible genes in terms of induction time course, LPS dose response, and sensitivity to co-stimulation with IFN-gamma. Induction of PAI-2 mRNA in subclones of the cell line RAW 264 was not uniform, reflecting heterogeneous expression in the parent line. The expression pattern of PAI-2 is discussed in terms of a possible role in LPS-induced pathology such as septicemia.
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PMID:Regulation of the plasminogen activator inhibitor-2 (PAI-2) gene in murine macrophages. Demonstration of a novel pattern of responsiveness to bacterial endotoxin. 1041 Oct 6

Type 1 plasminogen activator inhibitor (PAI-1), a major physiological inhibitor of plasminogen activation, is an important component of the hepatic acute phase response. We studied the acute phase regulation of murine hepatic PAI-1 in response to systemic toxicity and local tissue injury in both wild-type mice and in mice in which the interleukin (IL)-1beta gene had been inactivated by gene targeting. Endotoxin induced plasma PAI-1 antigen levels and PAI-1 mRNA accumulation in liver to the same extent in both wild-type and IL-1beta-deficient mice. In contrast, turpentine increased plasma PAI-1 and hepatic PAI-1 mRNA accumulation in wild-type mice but not in IL-1beta-deficient mice. Intraperitoneal injection of murine IL-1beta rapidly increased plasma PAI-1 and hepatic PAI-1 mRNA in both wild-type and IL-1beta-deficient mice. These results suggest that IL-1beta is a critical inducer of hepatic PAI-1 gene expression during the acute phase response to local tissue injury. In situ hybridization studies revealed that hepatocytes are the cells primarily responsible for the hepatic expression of the PAI-1 gene induced by lipopolysaccharide and turpentine.
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PMID:IL-1beta mediates induction of hepatic type 1 plasminogen activator inhibitor in response to local tissue injury. 1051 46

The effects of fluvastatin, a synthetic hydroxymethylglutaryl coenzyme A (HMG-CoA) inhibitor, on the biosynthesis of tissue plasminogen activator (t-PA) and of its major physiological inhibitor (plasminogen activator inhibitor type 1, PAI-1) were investigated in cultured human umbilical vein endothelial cells (HUVEC). Fluvastatin (0.1 to 2.5 microM), concentration-dependently reduced the release of PAI-1 antigen by unstimulated HUVEC, subsequent to a reduction in PAI-1 steady-state mRNA levels and de novo protein synthesis. In contrast, it increased t-PA secretion. The drug also reduced PAI-1 antigen secreted in response to 10 microg/ml bacterial lipopolysaccharide (LPS), 100 U/ml tumour necrosis factor alpha (TNFalpha) or 0.1 microM phorbol myristate acetate (PMA). Mevalonate (100 microM), a precursor of isoprenoids, added to cells simultaneously with fluvastatin, suppressed the effect of the drug on PAI-1 both in unstimulated and stimulated cells as well as on t-PA antigen. Among intermediates of the isoprenoid pathway, all-transgeranylgeraniol (5 microM) but not farnesol (10 microM) prevented the effect of 2.5 microM fluvastatin on PAI-1 antigen, which suggests that the former intermediate of the isoprenoid synthesis is responsible for the observed effects.
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PMID:Fluvastatin inhibits basal and stimulated plasminogen activator inhibitor 1, but induces tissue type plasminogen activator in cultured human endothelial cells. 1092 71

Monocytes play a pivotal role in various human infectious and inflammatory diseases. To reveal a whole picture of pathophysiologic function of activated human monocytes, this study used the serial analysis of gene expression (SAGE) procedure in lipopolysaccharide (LPS)-stimulated human monocytes. A total of 35 874 tags corresponding to more than 12 000 different transcripts were sequenced. Comparison of gene expression profile with that of resting monocytes revealed the LPS-inducible gene expression profile. Many cytokines and chemokines, including interleukin (IL)-6, IL-1alpha, IL-1beta, tumor necrosis factor (TNF)-alpha, macrophage inflammatory protein (MIP)-1beta, MIP-2beta, MIP-2alpha, liver and activation-regulated chemokine (LARC), MIP-1alpha, thymus and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC), regulated on activation, normal T cell expressed and secreted (RANTES), growth-regulated oncogene (GRO) alpha, and IL-8, were observed in the highest inducible transcripts. Other genes encoding plasminogen activator inhibitor type 2 (PAI-2), Hc-gp39, apolipoproteins, malate dehydrogenase, matrix metalloproteinase-9 (MMP-9), and cyclooxygenase (COX2) were also highly elevated in LPS-stimulated monocytes. Moreover, up-regulation of Naf1beta, IL-7 receptor, adenosine receptor A2a, and many novel genes was newly identified. These results suggest that the LPS-inducible gene products may be involved in cell activation and migration, angiogenesis, tissue remodeling, and metabolism, and thus may orchestrate the inflammatory reactions. On the other hand, the expression of numerous sets of novel genes was discovered to be down-regulated on LPS stimulation. This study represents the first comprehensive analysis of LPS-inducible gene expression in human monocytes and provides tremendous novel information for the function of LPS-activated monocytes and targets for diagnosing, monitoring, and treating sepsis and various human infectious and inflammatory diseases.
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PMID:Comprehensive gene expression profile of LPS-stimulated human monocytes by SAGE. 1100 15

Protein C is the zymogen of an anticoagulant serine protease and is converted to its active form (activated protein C: APC) by thrombin in the presence of thrombomodulin. APC plays an important role in regulating coagulation and fibrinolysis by inactivating not only blood coagulation factors Va and VIIIa but also type-1 plasminogen activator inhibitor (PAI-1). The aim of the present study was to examine the effect of a human APC product (designated as CTC-111), compared with that of heparin, on the disseminated intravascular coagulation (DIC) induced by lipopolysaccharide (LPS) in rats. LPS (1 mg/kg/h) infusion was performed through a femoral vein for 4 h. One-fifth amount of the total dosage of CTC-111 or heparin was injected into the other femoral vein, followed by a 4-h infusion of the remainder. Both CTC-111 (10,000-100,000 U/kg) and heparin (400-800 IU/kg) inhibited the decrease in platelet count and fibrinogen level equally. The prolonged activated partial thromboplastin time and prothrombin time observed in DIC rats were further elongated in both CTC-111- and heparin-treated rats. But, this prolongation was less in CTC-111-treated rats than in the heparin-treated ones. Heparin inhibited the increase in fibrin and fibrinogen degradation products more prominently than CTC-111. On the other hand, CTC-111 strongly inhibited the increase in PAI-1 activity but heparin did not. These results suggest that CTC-111 may enhance fibrinolysis through its direct inhibitory effect on PAI-1. The parameters for liver or renal damage, i.e., plasma glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT), creatinine (Cre) and blood urea nitrogen (BUN), were significantly increased by LPS infusion. Both CTC-111 (100,000 U/kg) and heparin (800 IU/kg) decreased the increase in GOT and GPT levels significantly, whereas neither affected the increase in Cre or BUN. From these results, the activation of the blood coagulation system might partially contribute to the progression of liver damage caused by LPS, and might be less involved in the progression of renal damage in this model. In conclusion, CTC-111 showed both anticoagulant and profibrinolytic activity in the LPS-induced DIC model without excessive prolongation of coagulation time. From these results, CTC-111 is expected to be a useful remedy for DIC without the risk of bleeding.
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PMID:Effect of activated human protein C on disseminated intravascular coagulation induced by lipopolysaccharide in rats. 1105 Jun 97

Both tissue plasminogen activator (t-PA) and plasminogen activator inhibitor 2 (PAI-2) are important proteolysis factors present in inflamed human periodontal tissues. The aim of the present study was to investigate the effect of lipopolysaccharide (LPS) on the synthesis of t-PA and PAI-2 by human gingival fibroblasts (HGF). LPS from different periodontal pathogens including Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Fusobacterium nucleatum were extracted by the hot phenol water method. The levels of t-PA and PAI-2 secreted into the cell culture media were measured by enzyme-linked immunosorbent assays (ELISA). The mRNA for t-PA and PAI-2 were measured by RT-PCR. The results showed t-PA synthesis was increased in response to all types of LPS studied and PAI-2 level was increased by LPS from A. actinomycetemcomitans and F. nucleatum, but not P. gingivalis. When comparing the effects of LPS from non-periodontal bacteria (Escherichia coli and Salmonella enteritidis) with the LPS from periodontal pathogens, we found that the ratio of t-PA to PAI-2 was greater following exposure of the cells to LPS from periodontal pathogens. The highest ratio of t-PA to PAI-2 was found in those cells exposed to LPS from P. gingivalis. These results indicate that LPS derived from periodontal pathogens may cause unbalanced regulation of plasminogen activator and plasminogen activator inhibitor by HGF and such an effect may, in part, contribute to the destruction of periodontal connective tissue through dysregulated pericellular proteolysis.
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PMID:Effect of lipopolysaccharide from periodontal pathogens on the production of tissue plasminogen activator and plasminogen activator inhibitor 2 by human gingival fibroblasts. 1124 1

Plasminogen activator inhibitor 1 (PAI-1) is one of important coagulant factors. Endotoxin lipopolysaccharide (LPS) induces thrombosis by stimulating PAI-1 secretion of vascular cells (EC). Using sandwich enzyme-linked immunosorbent assay (ELISA) and Northern blot, was investigated the effects of Chinese medicine ligustrazini on PAI-1 expression in EC and LPS-stimulated EC. The results showed that ligustrazini inhibited both basal and LPS-induced PAI-1 mRNA expression in EC. The effect of ligustrazini on LPS-induced PAI-1 secretion worked in a dose-dependent manner. This study provided theoretic and experimental evidence for use of ligustrazini against septic shock and cardiovascular diseases.
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PMID:Ligustrazini inhibits endotoxin induced PAI-1 expression in human umbilical vein endothelial cells. 1152 51

To determine the role of CD14 in lipopolysaccharide (LPS)-induced effects on coagulation and fibrinolysis in humans, 16 healthy subjects received an intravenous injection of LPS preceded by intravenous IC14, a recombinant chimeric monoclonal antibody against human CD14, or placebo. LPS-induced coagulation activation (tissue-factor mRNA in whole blood cells and plasma concentrations of F1+2) was not influenced by IC14, whereas the antibody reduced the increase in thrombin-antithrombin complexes and soluble fibrin. LPS injection also was associated with an early activation of fibrinolysis (plasma concentrations of tissue-type plasminogen activator and plasmin-alpha(2)-antiplasmin complexes), followed by an inhibitory response (plasminogen activator inhibitor type 1), which were attenuated by IC14. Furthermore, LPS reduced thrombin-activatable fibrinolysis-inhibitor antigen levels and increased soluble thrombomodulin levels, which were not influenced by IC14. These results suggest that different hemostatic responses during endotoxemia may proceed via CD14-dependent and -independent pathways.
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PMID:Effects of IC14, an anti-CD14 antibody, on coagulation and fibrinolysis during low-grade endotoxemia in humans. 1250 46

P38 mitogen-activated protein kinase (MAPK) is an important component of intracellular signaling cascades that initiate various inflammatory cellular responses. To determine the role of p38 MAPK in the procoagulant response to lipopolysaccharide (LPS), 24 healthy subjects were exposed to an intravenous dose of LPS (4 ng/kg), preceded 3 hours earlier by orally administered 600 or 50 mg BIRB 796 BS (a specific p38 MAPK inhibitor), or placebo. The 600-mg dose of BIRB 796 BS strongly inhibited LPS-induced coagulation activation, as measured by plasma concentrations of the prothrombin fragment F1 + 2. BIRB 796 BS also dose dependently attenuated the activation and subsequent inhibition of the fibrinolytic system (plasma tissue-type plasminogen activator, plasmin-alpha2-antiplasmin complexes, and plasminogen activator inhibitor type 1) and endothelial cell activation (plasma soluble E-selectin and von Willebrand factor). Activation of p38 MAPK plays an important role in the procoagulant and endothelial cell response after in vivo exposure to LPS.
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PMID:Inhibition of coagulation, fibrinolysis, and endothelial cell activation by a p38 mitogen-activated protein kinase inhibitor during human endotoxemia. 1257 15

Tissue factor (TF) and lipopolysaccharide (LPS) are frequently used to induce disseminated intravascular coagulation (DIC) in experimental animal models. Although the pathophysiology of DIC may differ depending on which agent is used for induction, previous studies on models of DIC have not distinguished which DIC-inducing agent was used. In the present paper, we evaluate the characteristics of TF-induced and LPS-induced DIC using two types of DIC models, with special reference to selected hemostatic parameters and pathological findings within the kidney. Male Wistar rats were administered TF (3.75 U/kg; sustained infusion for 4 h) or LPS (30 mg/kg; sustained infusion for 4 h) via the tail vein, and blood sampling was performed at 0, 1, 3, 4, 5, 7, 9, 11, and 28 h. Judging from changes in the levels of thrombin-antithrombin complex, fibrinogen levels, and platelet counts, it is reasonable to conclude that the severity of both types of experimental DIC is similar with regard to hemostatic activation and consumption coagulopathy. A marked elevation in the level of D-dimer was noted without any organ dysfunction or much fibrin deposition in the kidney upon administration of TF. However, a markedly prolonged period of elevation in plasminogen activator inhibitor activity, a prolonged depression in antithrombin III activity, severe organ failure, and a markedly prolonged period of fibrin deposition in the kidney was observed following LPS administration. A modest number of the rats from the TF-induced DIC model died during the experimental period, whereas a large number of rats died during LPS-induced DIC, especially after 9 h. Since the time course of the pathophysiology differed remarkably among the TF-induced and LPS-induced DIC models in rats, we recommend that TF-induced and LPS-induced DIC be approached as distinct models in order to determine the implications of their experimental and clinical use.
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PMID:Pathophysiology of disseminated intravascular coagulation (DIC) progresses at a different rate in tissue factor-induced and lipopolysaccharide-induced DIC models in rats. 1269 43


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