scholarly journals Porphyromonas gingivalis Gingipains-Mediated Degradation of Plasminogen Activator Inhibitor-1 Leads to Delayed Wound Healing Responses in Human Endothelial Cells

2021 ◽  
pp. 1-14
Author(s):  
Li-Ting Song ◽  
Hiroyuki Tada ◽  
Takashi Nishioka ◽  
Eiji Nemoto ◽  
Takahisa Imamura ◽  
...  
Keyword(s):  
Wound Healing ◽  
Endothelial Cells ◽  
Plasminogen Activator ◽  
Porphyromonas Gingivalis ◽  
Plasminogen Activator Inhibitor ◽  
Human Endothelial Cells ◽  
Plasminogen Activator Inhibitor 1 ◽  
Delayed Wound Healing ◽  
Activator Inhibitor ◽  
Pai 1

Plasminogen activator inhibitor-1 (PAI-1), a serine protease inhibitor, is constitutively produced by endothelial cells and plays a vital role in maintaining vascular homeostasis. Chronic periodontitis is an inflammatory disease characterized by bleeding of periodontal tissues that support the tooth. In this study, we aimed to determine the role of PAI-1 produced by endothelial cells in response to infections caused by the primary periodontal pathogen Porphyromonas gingivalis. We demonstrated that P. gingivalis infection resulted in significantly reduced PAI-1 levels in human endothelial cells. This reduction in PAI-1 levels could be attributed to the proteolysis of PAI-1 by P. gingivalis proteinases, especially lysine-specific gingipain-K (Kgp). We demonstrated the roles of these degradative enzymes in the endothelial cells using a Kgp-specific inhibitor and P. gingivalis gingipain-null mutants, in which the lack of the proteinases resulted in the absence of PAI-1 degradation. The degradation of PAI-1 by P. gingivalis induced a delayed wound healing response in endothelial cell layers via the low-density lipoprotein receptor-related protein. Our results collectively suggested that the proteolysis of PAI-1 in endothelial cells by gingipains of P. gingivalis might lead to the deregulation of endothelial homeostasis, thereby contributing to the permeabilization and dysfunction of the vascular endothelial barrier.

Regulation of Plasminogen Activator Inhibitor-1 mRNA in Human Endothelial Cells

1988 ◽  
Vol 60 (01) ◽  
pp. 063-067 ◽  
Author(s):  
E A van den Berg ◽  
E D Sprengers ◽  
M Jaye ◽  
W Burgess ◽  
T Maciag ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Plasminogen Activator ◽  
Growth Medium ◽  
Cdna Probe ◽  
Plasminogen Activator Inhibitor ◽  
Mrna Levels ◽  
Human Endothelial Cells ◽  
Plasminogen Activator Inhibitor 1 ◽  
Activator Inhibitor ◽  
Pai 1

SummaryThe plasminogen activator inhibitor (PAI-1) from endothelial cells is a potentially important regulator of plasminogen activator activity. Cultured human endothelial cells increase their PAI-1 production upon stimulation with LPS and TNF, agents that are known to cause an increase in PAI-1 levels in vivo.We isolated a PAI-1 cDNA probe, and by RNA hybridization analysis studied the regulation of PAI-1 mRNA synthesis in human endothelial artery cells. Freshly isolated endothelial cells do not contain detectable amounts of PAI-1 mRNA, but after adherence and incubation for 18 h in growth medium produce considerable amounts of PAI-1 activity and contain PAI-1 mRNA levels comparable to those found in subcultured cells. When subcultured endothelial cells are incubated for 6 h with LPS or TNF, both species of PAI-1 mRNA increase 10 to 20 fold, while PAI-1 activity in the growth medium increases only 1.5 to 2 fold. Stimulation of endothelial cells in the presence of cycloheximide (CHX) results in superinduction of mainly the 3.0 kb PAI-1 mRNA. The 3' end of this mRNA contains a 60 bp AT-rich sequence, that resembles 3' sequences present in a number of other genes superinducible with CHX.

Abstract T P75: Temporal Profiles of Plasminogen Activator Inhibitor-1 Concentration and Activity Changes in Circulation after Focal Stroke and Tissue Type Plasminogen Activator Administration in Rats

Stroke ◽  
2014 ◽  
Vol 45 (suppl_1) ◽  
Author(s):  
Qi Liu ◽  
Xiang Fan ◽  
Helen Brogren ◽  
Ming-Ming Ning ◽  
Eng H Lo ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Plasminogen Activator ◽  
Plasminogen Activator Inhibitor ◽  
Tissue Type ◽  
Plasminogen Activator Inhibitor 1 ◽  
Type Plasminogen Activator ◽  
Temporal Profiles ◽  
Activator Inhibitor ◽  
Pai 1

Aims: Plasminogen activator inhibitor-1 (PAI-1) is the main and potent endogenous tissue-type plasminogen activator (tPA) inhibitor, but an important question on whether PAI-1 in blood stream responds and interferes with the exogenously administered tPA remains unexplored. We for the first time investigated temporal profiles of PAI-1 concentration and activity in circulation after stroke and tPA administration in rats. Methods: Permanent MCAO focal stroke of rats were treated with saline or 10mg/kg tPA at 3 hours after stroke (n=10 per group). Plasma (platelet free) PAI-1 antigen and activity levels were measured by ELISA at before stroke, 3, 4.5 (1.5 hours after saline or tPA treatments) and 24 hours after stroke. Since vascular endothelial cells and platelets are two major cellular sources for PAI-1 in circulation, we measured releases of PAI-1 from cultured endothelial cells and isolated platelets after direct tPA (4 μg/ml) exposures for 60 min in vitro by ELISA (n=4 per group). Results: At 3 hours after stroke, both plasma PAI-1 antigen and activity were significantly increased (3.09±0.67, and 3.42±0.57 fold of before stroke baseline, respectively, all data are expressed as mean±SE). At 4.5 hours after stroke, intravenous tPA administration significantly further elevated PAI-1 antigen levels (5.26±1.24), while as expected that tPA neutralized most elevated PAI-1 activity (0.33±0.05). At 24 hours after stroke, PAI-1 antigen levels returned to the before baseline level, however, there was a significantly higher PAI-1 activity (2.51±0.53) in tPA treated rats. In vitro tPA exposures significantly increased PAI-1 releases into culture medium in cultured endothelial cells (1.65±0.08) and platelets (2.02±0.17). Conclution: Our experimental results suggest that tPA administration may further elevate stroke-increased blood PAI-1 concentration, but also increase PAI-1 activity at late 24 hours after stroke. The increased PAI-1 releases after tPA exposures in vitro suggest tPA may directly stimulate PAI-1 secretions from vascular walls and circulation platelets, which partially contributes to the PAI-1 elevation observed in focal stroke rats. The underlying regulation mechanisms and pathological consequence need further investigation.

scholarly journals Conversion of the active to latent plasminogen activator inhibitor from human endothelial cells

Blood ◽  
1987 ◽  
Vol 70 (4) ◽  
pp. 1090-1098
Author(s):  
EG Levin ◽  
L Santell
Keyword(s):  
Endothelial Cells ◽  
Conditioned Medium ◽  
Plasminogen Activator ◽  
Active Form ◽  
Plasminogen Activator Inhibitor ◽  
Human Endothelial Cells ◽  
Inhibitor Activity ◽  
Latent Form ◽  
Activator Inhibitor ◽  
Pai 1

The plasminogen activator inhibitor from human endothelial cells (PAI- 1) exists in two forms in the culture medium: an active form that binds to and inactivates plasminogen activators and a latent form that in its native state has no anti-activator activity. Inhibitor activity associated with the latent form can be generated by treatment with protein denaturants and makes up more than 98% of the total inhibitor activity in conditioned medium. Plasminogen activator inhibitor activity is also found in cell cytosol. This inhibitor activity is stable to SDS-treatment but is not enhanced by it. We investigated the relationship between this active cell-associated inhibitor and the latent PAI-1 found in the conditioned medium. Both intracellular and extracellular inhibitors were immunoprecipitated by a monoclonal antibody produced against the latent inhibitor from HT1080 fibrosarcoma cells and electrophoresis on SDS gels of various acrylamide concentrations demonstrated that both forms had the same Mr. Incubation of cytosol inhibitor at 37 degrees C resulted in a decline in inhibitor activity with a half-life of approximately 4 hours, a rate of decline similar to that of the active PAI-1 in conditioned medium, with less than 10% of the original activity present after eight hours. This decline is accelerated at higher temperatures and is not affected by the presence of a variety of protease inhibitors. Approximately 90% of the activity can be regenerated after SDS treatment suggesting that the cell associated inhibitor, during incubation at 37 degrees C, converts to a form similar to that found in conditioned medium. Despite these similarities, the apparent Stoke's radii of the active intracellular inhibitor and the latent inhibitor in conditioned medium were significantly different with values of 2.77 nm and 2.40 nm for active and latent PAI-1, respectively. Incubation of the active form at 37 degrees C resulted in the shift of the Stoke's radius to that similar to the latent PAI-1 (2.45 nm). Thus, the active and latent PAI-1, while being immunologically similar and of the same apparent Mr, can be differentiated by their behavior on gel permeation columns. This suggests that the intracellular inhibitor is a precursor to the latent form.

scholarly journals Plasminogen activator inhibitor-1 secretion of endothelial cells increases fibrinolytic resistance of an in vitro fibrin clot: evidence for a key role of endothelial cells in thrombolytic resistance

Blood ◽  
1996 ◽  
Vol 87 (10) ◽  
pp. 4204-4213 ◽  
Author(s):  
S Handt ◽  
WG Jerome ◽  
L Tietze ◽  
RR Hantgan
Keyword(s):  
Endothelial Cells ◽  
Blood Vessels ◽  
Plasminogen Activator ◽  
Plasminogen Activator Inhibitor ◽  
Time Dependent ◽  
Plasminogen Activator Inhibitor 1 ◽  
Necrosis Factor Alpha ◽  
Activator Inhibitor ◽  
Pai 1

Time-dependent thrombolytic resistance is a critical problem in thrombolytic therapy for acute myocardial infarction. Platelets have been regarded as the main source of plasminogen activator inhibitor-1 (PAI-1) found in occlusive platelet-rich clots. However, endothelial cells are also known to influence the fibrinolytic capacity of blood vessels, but their ability to actively mediate time-dependent thrombolytic resistance has not been fully established. We will show that, in vitro, tumor necrosis factor-alpha-stimulated endothelial cells secrete large amounts of PAI-1 over a period of hours, which then binds to fibrin and protects the clot from tissue plasminogen activator- induced fibrinolysis. In vivo, endothelial cells covering atherosclerotic plaques are influenced by cytokines synthesized by plaque cells. Therefore, we propose that continuous activation of endothelial cells in atherosclerotic blood vessels, followed by elevated PAI-1 secretion and storage of active PAI-1 in the fibrin matrix, leads to clot stabilization. This scenario makes endothelial cells a major factor in time-dependent thrombolytic resistance.

REGULATION OF PLASMINOGEN ACTIVATOR INHIBITOR-1 mRNA IN HUMAN ENDOTHELIAL CELLS

1987 ◽  
Author(s):  
E A van den Berg ◽  
E Sprengers ◽  
M Jaye ◽  
W Burgess ◽  
V W M van Hinsbergh
Keyword(s):  
Endothelial Cells ◽  
Amino Acid ◽  
Amino Acid Sequence ◽  
Plasminogen Activator ◽  
Cdna Clone ◽  
Plasminogen Activator Inhibitor ◽  
Mrna Levels ◽  
Human Endothelial Cells ◽  
Activator Inhibitor ◽  
Pai 1

Cultured human endothelial cells (HEC) increase their production of plasminogen activator inhibitor (PAI-1) upon stimulation with endotoxin and IL-1, agents that are known to cause an increase in PAI-1 levels in vivo. In order to study the regulation of PAI-1 synthesis at the mRNA level, we isolated a cDNA clone for the human PAI-1 gene from an endothelial expression cDNA library in λ gt 11 by screening with a PAI-1 specific antibody. Three positive cross-hybridizing clones were isolated. The longest insert (1500 bp) was partially sequenced (1000 bp). The sequence was identical to the PAI-1 sequence recently reported by others. The identity of the cDNA clone was further confirmed by comparison with part of the amino acid sequence of PAI-1. For that purpose t-PA-PAI-1 complex was purified from HEC conditioned medium by immunoadsorption to anti-t-PA IgG, and a suitable peptide was sequenced after comparison of the HPLC elution profiles of CNBr digests of t-PA and t-PA-PAI-1 complex. The amino acid sequence (M)FRQFQADFT completely matches the sequence predicted from the cDNA sequence.By hybridization of the cDNA probe to Northern blots of total cellular RNA from human umbilical vein and artery EC (HUVEC, HUAEC), two transcripts of 2.3 and 3 kb were found. Primary HUAEC, incubated for 18 hours in growth medium, produced considerable although variable levels of PAI-1 activity and contained PAI-1 mRNA levels comparable to those found in subcultured HUAEC. When subcultured HUEC were incubated for 6 h with endotoxin, IL-1 or TNF, a 2-fold increase in PAI-1 mRNA was found with each of these mediators. Stimulation of the cells in the presence of cycloheximide resulted in a further increase of the 3 kb PAI-1 transcript. The 3’ end of this transcript contains a 75 bp AT-rich sequence. Similar 3’ AT-rich sequences have been found in mRNA’s for a number of inflammatory mediators and cellular oncogenes, and in some cases it has been shown that removal of the sequence increased mRNA stability. The influence of cyclohex-imid on the larger PAI-1 transcript might be explained by inhibition of synthesis of a specific nuclease that controls the level of mRNA’s harbouring such an AT rich sequence.

Thymosin β4 induces the synthesis of plasminogen activator inhibitor 1 in cultured endothelial cells and increases its extracellular expression

Blood ◽  
2004 ◽  
Vol 103 (4) ◽  
pp. 1319-1324 ◽  
Author(s):  
Khalid N. I. Al-Nedawi ◽  
Malgorzata Czyz ◽  
Radoslaw Bednarek ◽  
Janusz Szemraj ◽  
Maria Swiatkowska ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Plasminogen Activator ◽  
Human Fibroblasts ◽  
Plasminogen Activator Inhibitor ◽  
Binding Activity ◽  
Mitogen Activated Protein Kinase ◽  
Thymosin Β4 ◽  
Plasminogen Activator Inhibitor 1 ◽  
Activator Inhibitor ◽  
Pai 1

Abstract Thymosin β4(Tβ4), a 4.9-kDa polypeptide primarily known as a main G-actin–sequestering peptide, is present in high concentrations in various cells and in the circulation. We have found that Tβ4 upregulates the expression of plasminogen activator inhibitor 1 (PAI-1) in endothelial cells measured both at the level of mRNA and protein synthesis. This effect seems to be cell specific and was not observed when other cells such as human fibroblasts, PC3, and U937 were tested. Tβ4 significantly activated the PAI-1 promoter in EA.hy 926 cells transiently transfected either with plasmid p800LUC containing PAI-1 promoter fragment (–800 to +71) or the PAI-1 promoter linked with green fluorescent protein. Tβ4 mediated up-regulation of PAI-1 involved activation of the mitogen-activated protein kinase cascade. Furthermore, Tβ4 enhanced c-Fos/c-Jun DNA-binding activity to the activator protein 1 (AP-1)–like element (–59 to –52). The specificity of this binding activity was demonstrated by competition electrophoretic mobility shift assay and after transfection of EA.hy 926 cells with the mutated PAI-1 promoter. Taken together, these data indicate that, in response to Tβ4 stimulation, AP-1 activity increases to enhance PAI-1 transcription through its unique AP-1–like element at –59 to –52 in the PAI-1 promoter.

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