Vascular release of plasminogen activator inhibitor-1 impairs fibrinolysis during acute arterial thrombosis in mice

The role of plasminogen activator inhibitor-1 (PAI-1) in the plasma, blood platelets, and vessel wall during acute arterial thrombus formation was investigated in gene-deficient mice. Photochemically induced thrombosis in the carotid artery was analyzed via transillumination. In comparison to thrombosis in C57BL/6J wild-type (wt) mice (113 ± 19 × 106 arbitrary light units [AU] n = 15, mean ± SEM), thrombosis in PAI-1−/− mice (40 ± 10 × 106 AU, n = 13) was inhibited (P < .01), indicating that PAI-1 controls fibrinolysis during thrombus formation. Systemic administration of murine PAI-1 into PAI-1−/− mice led to a full recovery of thrombotic response. Occurrence of fibrinolytic activity was confirmed in 2-antiplasmin (2-AP)–deficient mice. The sizes of thrombi developing in wt mice, in 2-AP+/− and 2-AP−/− mice were 102 ± 35, 65 ± 8.1, and 13 ± 6.1 × 106 AU, respectively (n = 6 each) (P < .05), compatible with functional plasmin inhibition by 2-AP. In contrast, thrombi in wt mice, t-PA−/− and u-PA−/−mice were comparable, substantiating efficient inhibition of fibrinolysis by the combined PAI-1/2-AP action. Platelet depletion and reconstitution confirmed a normal thrombotic response in wt mice, reconstituted with PAI-1−/− platelets, but weak thrombosis in PAI-1−/− mice reconstituted with wt platelets. Accordingly, murine (wt) PAI-1 levels in platelet lysates and releasates were 0.43 ± 0.09 ng/109 platelets and plasma concentrations equaled 0.73 ± 0.13 ng/mL. After photochemical injury, plasma PAI-1 rose to 2.9 ± 0.7 ng/mL (n = 9, P < .01). The plasma rise was prevented by ligating the carotid artery. Hence, during acute thrombosis, fibrinolysis is efficiently prevented by plasma 2-AP, but also by vascular PAI-1, locally released into the circulation after endothelial injury.

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Vascular release of plasminogen activator inhibitor-1 impairs fibrinolysis during acute arterial thrombosis in mice

Blood ◽

10.1182/blood.v96.1.153 ◽

2000 ◽

Vol 96 (1) ◽

pp. 153-160 ◽

Cited By ~ 46

Author(s):

Tomihisa Kawasaki ◽

Mieke Dewerchin ◽

Henri R. Lijnen ◽

Jos Vermylen ◽

Marc F. Hoylaerts

Keyword(s):

Carotid Artery ◽

Plasminogen Activator ◽

Thrombus Formation ◽

Blood Platelets ◽

Plasma Concentrations ◽

Plasminogen Activator Inhibitor ◽

Plasminogen Activator Inhibitor 1 ◽

Deficient Mice ◽

Activator Inhibitor ◽

Pai 1

Abstract The role of plasminogen activator inhibitor-1 (PAI-1) in the plasma, blood platelets, and vessel wall during acute arterial thrombus formation was investigated in gene-deficient mice. Photochemically induced thrombosis in the carotid artery was analyzed via transillumination. In comparison to thrombosis in C57BL/6J wild-type (wt) mice (113 ± 19 × 106 arbitrary light units [AU] n = 15, mean ± SEM), thrombosis in PAI-1−/− mice (40 ± 10 × 106 AU, n = 13) was inhibited (P < .01), indicating that PAI-1 controls fibrinolysis during thrombus formation. Systemic administration of murine PAI-1 into PAI-1−/− mice led to a full recovery of thrombotic response. Occurrence of fibrinolytic activity was confirmed in 2-antiplasmin (2-AP)–deficient mice. The sizes of thrombi developing in wt mice, in 2-AP+/− and 2-AP−/− mice were 102 ± 35, 65 ± 8.1, and 13 ± 6.1 × 106 AU, respectively (n = 6 each) (P < .05), compatible with functional plasmin inhibition by 2-AP. In contrast, thrombi in wt mice, t-PA−/− and u-PA−/−mice were comparable, substantiating efficient inhibition of fibrinolysis by the combined PAI-1/2-AP action. Platelet depletion and reconstitution confirmed a normal thrombotic response in wt mice, reconstituted with PAI-1−/− platelets, but weak thrombosis in PAI-1−/− mice reconstituted with wt platelets. Accordingly, murine (wt) PAI-1 levels in platelet lysates and releasates were 0.43 ± 0.09 ng/109 platelets and plasma concentrations equaled 0.73 ± 0.13 ng/mL. After photochemical injury, plasma PAI-1 rose to 2.9 ± 0.7 ng/mL (n = 9, P < .01). The plasma rise was prevented by ligating the carotid artery. Hence, during acute thrombosis, fibrinolysis is efficiently prevented by plasma 2-AP, but also by vascular PAI-1, locally released into the circulation after endothelial injury.

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The plasminogen activator inhibitor-1 (PAI-1) promoter haplotype is related to PAI-1 plasma concentrations in lean individuals

Atherosclerosis ◽

10.1016/j.atherosclerosis.2005.01.036 ◽

2005 ◽

Vol 181 (2) ◽

pp. 275-284 ◽

Cited By ~ 14

Author(s):

Maartje Verschuur ◽

Annemarie Jellema ◽

Else M. Bladbjerg ◽

Edith J. M. Feskens ◽

Ronald P. Mensink ◽

...

Keyword(s):

Plasminogen Activator ◽

Plasma Concentrations ◽

Plasminogen Activator Inhibitor ◽

Plasminogen Activator Inhibitor 1 ◽

Activator Inhibitor ◽

Pai 1 ◽

Promoter Haplotype

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Fibrate-modulated Expression of Fibrinogen, Plasminogen Activator Inhibitor-1 and Apolipoprotein A-I in Cultured Cynomolgus Monkey Hepatocytes

Thrombosis and Haemostasis ◽

10.1055/s-0037-1615393 ◽

1998 ◽

Vol 80 (12) ◽

pp. 942-948 ◽

Cited By ~ 29

Author(s):

M. Kockx ◽

H. M. G. Princen ◽

T. Kooistra

Keyword(s):

Plasminogen Activator ◽

Cynomolgus Monkey ◽

Plasma Concentrations ◽

Plasminogen Activator Inhibitor ◽

Peroxisome Proliferator ◽

Plasminogen Activator Inhibitor 1 ◽

Apolipoprotein A ◽

Activator Inhibitor ◽

Pai 1

SummaryFibrates are used to lower plasma triglycerides and cholesterol levels in hyperlipidemic patients. In addition, fibrates have been found to alter the plasma concentrations of fibrinogen, plasminogen activator inhibitor-1 (PAI-1) and apolipoprotein A-I (apo A-I). We have investigated the in vitro effects of fibrates on fibrinogen, PAI-1 and apo A-I synthesis and the underlying regulatory mechanisms in primary monkey hepatocytes.We show that fibrates time- and dose-dependently increase fibrinogen and apo A-I expression and decrease PAI-1 expression in cultured cynomolgus monkey hepatocytes, the effects demonstrating different potency for different fibrates. After three consecutive periods of 24 h the most effective fibrate, ciprofibrate (at 1 mmol/l), increased fibrinogen and apo A-I synthesis to 356% and 322% of control levels, respectively. Maximum inhibition of PAI-1 synthesis was about 50% of control levels and was reached by 1 mmol/l gemfibrozil or ciprofibrate after 48 h. A ligand for the retinoid-X-receptor (RXR), 9-cis retinoic acid, and specific activators of the peroxisome proliferator-activated receptor-α (PPARα), Wy14,643 and ETYA, influenced fibrinogen, PAI-1 and apo A-I expression in a similar fashion, suggesting a role for the PPARα/RXRα heterodimer in the regulation of these genes. When comparing the effects of the various compounds on PPARα trans-activation activity as determined in a PPARα-sensitive reporter gene system and the ability of the compounds to affect fibrinogen, PAI-1 and apo A-I antigen production, a good correlation (r = 0.80; p <0.01) between PPARα transactivation and fibrinogen expression was found. Apo A-I expression correlated only weakly with PPARα transactivation activity (r = 0.47; p = 0.24), whereas such a correlation was absent for PAI-1 (r = 0.03; p = 0.95). These results strongly suggest an involvement of PPARα in the regulation of fibrinogen gene expression.

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Functional Stability of Plasminogen Activator Inhibitor-1

The Scientific World JOURNAL ◽

10.1155/2014/858293 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 39

Author(s):

Songul Yasar Yildiz ◽

Pinar Kuru ◽

Ebru Toksoy Oner ◽

Mehmet Agirbasli

Keyword(s):

Plasminogen Activator ◽

Biological Effects ◽

Critical Role ◽

Plasma Concentrations ◽

Plasminogen Activator Inhibitor ◽

Tissue Type ◽

Plasminogen Activator Inhibitor 1 ◽

Type Plasminogen Activator ◽

Activator Inhibitor ◽

Pai 1

Plasminogen activator inhibitor-1 (PAI-1) is the main inhibitor of plasminogen activators, such as tissue-type plasminogen activator (t-PA) and urokinase-type plasminogen activator (u-PA), and a major regulator of the fibrinolytic system. PAI-1 plays a pivotal role in acute thrombotic events such as deep vein thrombosis (DVT) and myocardial infarction (MI). The biological effects of PAI-1 extend far beyond thrombosis including its critical role in fibrotic disorders, atherosclerosis, renal and pulmonary fibrosis, type-2 diabetes, and cancer. The conversion of PAI-1 from the active to the latent conformation appears to be unique among serpins in that it occurs spontaneously at a relatively rapid rate. Latency transition is believed to represent a regulatory mechanism, reducing the risk of thrombosis from a prolonged antifibrinolytic action of PAI-1. Thus, relying solely on plasma concentrations of PAI-1 without assessing its function may be misleading in interpreting the role of PAI-1 in many complex diseases. Environmental conditions, interaction with other proteins, mutations, and glycosylation are the main factors that have a significant impact on the stability of the PAI-1 structure. This review provides an overview on the current knowledge on PAI-1 especially importance of PAI-1 level and stability and highlights the potential use of PAI-1 inhibitors for treating cardiovascular disease.

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Bone marrow mesenchymal stem cell-derived exosomes promote plasminogen activator inhibitor 1 expression in vascular cells in the local microenvironment during rabbit osteonecrosis of the femoral head

Stem Cell Research & Therapy ◽

10.1186/s13287-020-01991-2 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Lu Li ◽

Yikai Wang ◽

Xiaobing Yu ◽

Yongming Bao ◽

Lijia An ◽

...

Keyword(s):

Bone Marrow ◽

Femoral Head ◽

Plasminogen Activator ◽

Vascular Endothelial Cells ◽

Thrombus Formation ◽

Plasminogen Activator Inhibitor ◽

Vascular Cells ◽

Plasminogen Activator Inhibitor 1 ◽

Activator Inhibitor ◽

Pai 1

Abstract Background Nontraumatic osteonecrosis of the femoral head (NONFH) is a highly disabling orthopedic disease in young individuals. Plasminogen activator inhibitor 1 (PAI-1) has been reported to be positively associated with NONFH. We aimed to investigate the dysregulating PAI-1 in bone marrow mesenchymal stem cells (BMMSCs) and vascular cells in rabbit steroid-induced NONFH. Methods To verify the hypothesis that BMMSCs could promote thrombus formation in a paracrine manner, we collected exosomes from glucocorticoid-treated BMMSCs (GB-Exo) to determine their regulatory effects on vascular cells. microRNA sequencing was conducted to find potential regulators in GB-Exo. Utilizing gain-of-function and knockdown approaches, we testified the regulatory effect of microRNA in exosomes. Results The expression of PAI-1 was significantly increased in the local microenvironment of the femoral head in the ONFH model. GB-Exo promoted PAI-1 expression in vascular smooth muscle cells and vascular endothelial cells. We also revealed that miR-451-5p in GB-Exo plays a crucial role for the elevated PAI-1. Moreover, we identified miR-133b-3p and tested its role as a potential inhibitor of PAI-1. Conclusions This study provided considerable evidence for BMMSC exosomal miR-mediated upregulation of the fibrinolytic regulator PAI-1 in vascular cells. The disruption of coagulation and low fibrinolysis in the femoral head will eventually lead to a disturbance in the microcirculation of NONFH. We believe that our findings could be of great significance for guiding clinical trials in the future.

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Serotonin induces the expression of tissue factor and plasminogen activator inhibitor-1 in cultured rat aortic endothelial cells

Blood ◽

10.1182/blood.v97.6.1697 ◽

2001 ◽

Vol 97 (6) ◽

pp. 1697-1702 ◽

Cited By ~ 37

Author(s):

Hidehiko Kawano ◽

Hajime Tsuji ◽

Hiromi Nishimura ◽

Shinzo Kimura ◽

Shingo Yano ◽

...

Keyword(s):

Endothelial Cells ◽

Receptor Antagonist ◽

Tissue Factor ◽

Plasminogen Activator ◽

Thrombus Formation ◽

Plasminogen Activator Inhibitor ◽

Plasminogen Activator Inhibitor 1 ◽

Aortic Endothelial Cells ◽

Activator Inhibitor ◽

Pai 1

Serotonin (5-hydroxytryptamine, or 5-HT), released from activated platelets, not only accelerates aggregation of platelets but also is known to promote mitosis, migration, and contraction of vascular smooth muscle cells (VSMCs). These effects are considered to contribute to thrombus formation and atherosclerosis. The aim of this study was to investigate the effects of 5-HT on the expressions of coagulative and fibrinolytic factors in rat aortic endothelial cells. Endothelial cells were stimulated with various concentrations of 5-HT (0.1∼10 μM), and the expressions of tissue factor (TF), tissue factor pathway inhibitor (TFPI), plasminogen activator inhibitor-1 (PAI-1), and tissue-type plasminogen activator (TPA) messenger RNAs (mRNAs) were evaluated by Northern blot analysis. The activities of TF and PAI-1 were also measured. TF and PAI-1 mRNA were increased significantly in a concentration- and time-dependent manner. However, TFPI and TPA mRNA expression did not change. The inductions of TF and PAI-1 mRNAs were inhibited by a 5-HT1/5-HT2 receptor antagonist (methiothepin) and a selective 5-HT2A receptor antagonist (MCI-9042). These results indicate that 5-HT increases procoagulant activity and reduces fibrinolytic activities of endothelial cells through the 5-HT2A receptor. It was concluded that the modulation of procoagulant and hypofibrinolytic activities of endothelial cells by 5-HT synergistically promotes thrombus formation at the site of vessel injury with the platelet aggregation, VSMC contraction, and VSMC proliferation.

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Bone Marrow Mesenchymal Stem Cell-derived Exosomes Promote Plasminogen Activator Inhibitor 1 Expression in Vascular Cells in the Local Microenvironment During Rabbit Osteonecrosis of the Femoral Head

10.21203/rs.2.23418/v1 ◽

2020 ◽

Author(s):

Lu Li ◽

Yikai Wang ◽

Xiaobing Yu ◽

Yongming Bao ◽

Lijia An ◽

...

Keyword(s):

Bone Marrow ◽

Femoral Head ◽

Plasminogen Activator ◽

Vascular Endothelial Cells ◽

Thrombus Formation ◽

Plasminogen Activator Inhibitor ◽

Vascular Cells ◽

Plasminogen Activator Inhibitor 1 ◽

Activator Inhibitor ◽

Pai 1

Abstract Background Nontraumatic osteonecrosis of the femoral head (NONFH) is a highly disabling orthopedic disease in young individuals. Plasminogen activator inhibitor 1 (PAI-1) has been reported to be positively associated with NONFH. We aimed to investigate the dysregulating PAI-1 in bone marrow mesenchymal stem cells (BMMSCs) and vascular cells in rabbit steroid-induced NONFH. Methods To verify the hypothesis that BMMSCs could promote thrombus formation in a paracrine manner, we collected exosomes from glucocorticoid-treated BMMSCs (GB-Exo) to determine their regulatory effects on vascular cells. microRNA sequencing was conducted to find potential regulators in GB-Exo. Utilizing gain-of-function and knockdown approaches, we testified regulatory effect of microRNA in exosomes. Results The expression of PAI-1 was significantly increased in local microenvironment of the femoral head in ONFH model. GB-Exo promoted PAI-1 expression in vascular smooth muscle cells and vascular endothelial cells. We also revealed that miR-451-5p in GB-Exo should be responsible for the elevated PAI-1. Moreover, we identified miR-133b-3p and tested its role as an potential inhibitor of PAI-1. Conclusions This study provided considerable evidence for BMMSC exosomal miR-mediated upregulation of the fibrinolytic regulators PAI-1 in vascular cells. The disruption of coagulation and low fibrinolysis in the femoral head will eventually lead to a disturbance in microcirculation of NONFH. We believe that our findings could be of great significance for guiding clinical trials in the future.

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Bone Marrow Mesenchymal Stem Cell-derived Exosomes Promote Plasminogen Activator Inhibitor 1 Expression in Vascular Cells in the Local Microenvironment During Rabbit Osteonecrosis of the Femoral Head

10.21203/rs.2.23418/v2 ◽

2020 ◽

Author(s):

Lu Li ◽

Yikai Wang ◽

Xiaobing Yu ◽

Yongming Bao ◽

Lijia An ◽

...

Keyword(s):

Bone Marrow ◽

Femoral Head ◽

Plasminogen Activator ◽

Vascular Endothelial Cells ◽

Thrombus Formation ◽

Plasminogen Activator Inhibitor ◽

Vascular Cells ◽

Plasminogen Activator Inhibitor 1 ◽

Activator Inhibitor ◽

Pai 1

Abstract Background: Nontraumatic osteonecrosis of the femoral head (NONFH) is a highly disabling orthopedic disease in young individuals. Plasminogen activator inhibitor 1 (PAI-1) has been reported to be positively associated with NONFH. We aimed to investigate the dysregulating PAI-1 in bone marrow mesenchymal stem cells (BMMSCs) and vascular cells in rabbit steroid-induced NONFH. Methods: To verify the hypothesis that BMMSCs could promote thrombus formation in a paracrine manner, we collected exosomes from glucocorticoid-treated BMMSCs (GB-Exo) to determine their regulatory effects on vascular cells. microRNA sequencing was conducted to find potential regulators in GB-Exo. Utilizing gain-of-function and knockdown approaches, we testified regulatory effect of microRNA in exosomes.Results: The expression of PAI-1 was significantly increased in local microenvironment of the femoral head in ONFH model. GB-Exo promoted PAI-1 expression in vascular smooth muscle cells and vascular endothelial cells. We also revealed that miR-451-5p in GB-Exo plays a crucial role for the elevated PAI-1. Moreover, we identified miR-133b-3p and tested its role as a potential inhibitor of PAI-1. Conclusions: This study provided considerable evidence for BMMSC exosomal miR-mediated upregulation of the fibrinolytic regulators PAI-1 in vascular cells. The disruption of coagulation and low fibrinolysis in the femoral head will eventually lead to a disturbance in microcirculation of NONFH. We believe that our findings could be of great significance for guiding clinical trials in the future.

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Plasminogen Activator Inhibitor-1 is Regulated Through Dietary Fat Intake and Heritability: Studies in Twins

Twin Research and Human Genetics ◽

10.1017/thg.2017.36 ◽

2017 ◽

Vol 20 (4) ◽

pp. 338-348 ◽

Cited By ~ 1

Author(s):

Anna Janina Engstler ◽

Turid Frahnow ◽

Michael Kruse ◽

Andreas Friedrich Hermann Pfeiffer ◽

Ina Bergheim

Keyword(s):

Adipose Tissue ◽

Mrna Expression ◽

Plasminogen Activator ◽

Plasma Concentrations ◽

Plasminogen Activator Inhibitor ◽

Fatty Tissue ◽

Plasminogen Activator Inhibitor 1 ◽

The Impact ◽

Activator Inhibitor ◽

Pai 1

In different pathophysiological conditions plasminogen activator inhibitor-1 (PAI-1) plasma concentrations are elevated. As dietary patterns are considered to influence PAI-1 concentration, we aimed to determine active PAI-1 plasma concentrations and mRNA expression in adipose tissue before and after consumption of a high-fat diet (HFD) and the impact of additive genetic effects herein in humans. For 6 weeks, 46 healthy, non-obese pairs of twins (aged 18–70) received a normal nutritionally balanced diet (ND) followed by an isocaloric HFD for 6 weeks. Active PAI-1 plasma levels and PAI-1 mRNA expression in subcutaneous adipose tissue were assessed after the ND and after 1 and 6 weeks of HFD. Active PAI-1 plasma concentrations and PAI-1 mRNA expression in adipose tissue were significantly increased after both 1 and 6 weeks of HFD when compared to concentrations determined after ND (p< .05), with increases of active PAI-1 being independent of gender, age, or changes of BMI and intrahepatic fat content, respectively. However, analysis of covariance suggests that serum insulin concentration significantly affected the increase of active PAI-1 plasma concentrations. Furthermore, the increase of active PAI-1 plasma concentrations after 6 weeks of HFD was highly heritable (47%). In contrast, changes in PAI-1 mRNA expression in fatty tissue in response to HFD showed no heritability and were independent of all tested covariates. In summary, our data suggest that even an isocaloric exchange of macronutrients — for example, a switch to a fat-rich diet — affects PAI-1 concentrations in humans and that this is highly heritable.

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