Differential Mechanisms of Plasminogen Activator Inhibitor-1 Gene Activation by Transforming Growth Factor-β and Tumor Necrosis Factor-α in Endothelial Cells

2001 ◽  
Vol 86 (12) ◽  
pp. 1563-1572 ◽  
Author(s):  
Yan Chen ◽  
Joanne Sloan-Lancaster ◽  
David Berg ◽  
Mark Richardson ◽  
Brian Grinnell ◽  
...  

SummaryPlasminogen activator inhibitor-1 (PAI-1) is a serine protease inhibitor (SERPIN) specific for tissue-type and urokinase-like plasminogen activators. High plasma PAI-1 activity is a risk factor for thrombotic diseases. Due to the short half-life of PAI-1, regulation of PAI-1 gene expression and secretion of active PAI-1 into the blood stream is important for hemostatic balance. We have investigated transcriptional control of PAI-1 gene expression in bovine aortic endothelial cells (BAECs) and human cell lines using PAI-1 5’ promoter-luciferase reporter assays. Contrary to the cytokine-induced up-regulation of PAI-1 mRNA and protein levels, we found that only transforming growth factor-β (TGF-β) was efficient in inducing PAI-1 promoter activation. Tissue necrosis factor-α (TNF-α) induced a small luciferase activity with the 2.5 kb PAI-1 promoter, but not with the PAI-800/4G/5G and p3TP-lux promoters. Next we investigated whether a lack of response to TNF-α was due to deficient signaling pathways. BAECs responded to TNF-α with robust NFκB promoter activation. TGF-β activated the p38 MAP kinase, while TNF-α activated both the SAPK/JNK and p38 MAP kinases. The ERK1/2 MAP kinases were constitutively activated in BAECs. BAEC therefore responded to TNF-α stimulation with activation of the MAP kinases and the NFκB transcriptional factors. We further measured the messenger RNA stability under the influence by TGF-β and TNF-α and found no difference. PAI-1 gene activation by TNF-α apparently is yet to be defined for the location of the response element and/or the signaling pathway, while TGF-β is the most important cytokine for PAI-1 transcriptional activation through its 5’ proximal promoter.

1999 ◽  
Vol 276 (6) ◽  
pp. C1391-C1397 ◽  
Author(s):  
Tomohiro Sakamoto ◽  
Janet Woodcock-Mitchell ◽  
Kousuke Marutsuka ◽  
John J. Mitchell ◽  
Burton E. Sobel ◽  
...  

Obesity is associated with hyperinsulinemia and elevated concentrations of tumor necrosis factor-α (TNF-α) in adipose tissue. TNF-α has been implicated as an inducer of the synthesis of plasminogen activator inhibitor-1 (PAI-1), the primary physiological inhibitor of fibrinolysis, mediated by plasminogen activators in cultured adipocytes. To identify mechanism(s) through which TNF-α induces PAI-1, 3T3-L1 preadipocytes were differentiated into adipocytes and exposed to TNF-α for 24 h. TNF-α selectively increased the synthesis of PAI-1 without increasing activity of plasminogen activators. Both superoxide (generated by xanthine oxidase plus hypoxanthine) and hydrogen peroxide were potent inducers of PAI-1, and hydroxyl radical scavengers completely abolished the TNF-α induction of PAI-1. Exposure of adipocytes to TNF-α or insulin alone over 5 days increased PAI-1 production. These agonists exert synergistic effects. Results obtained suggest that TNF-α stimulates PAI-1 production by adipocytes, an effect potentiated by insulin, and that adipocyte generation of reactive oxygen centered radicals mediates the induction of PAI-1 production by TNF-α. Because induction of PAI-1 by TNF-α is potentiated synergistically by insulin, both agonists appear likely to contribute to the impairment of fibrinolytic system capacity typical in obese, hyperinsulinemic patients.


2012 ◽  
Vol 303 (1) ◽  
pp. F11-F20 ◽  
Author(s):  
Jiandong Zhang ◽  
Jie Wu ◽  
Chunyan Gu ◽  
Nancy A. Noble ◽  
Wayne A. Border ◽  
...  

While elevated plasma prorenin levels are commonly found in diabetic patients and correlate with diabetic nephropathy, the pathological role of prorenin, if any, remains unclear. Prorenin binding to the (pro)renin receptor [(p)RR] unmasks prorenin catalytic activity. We asked whether elevated prorenin could be activated at the site of renal mesangial cells (MCs) through receptor binding without being proteolytically converted to renin. Recombinant inactive rat prorenin and a mutant prorenin that is noncleavable, i.e., cannot be activated proteolytically, are produced in 293 cells. After MCs were incubated with 10−7 M native or mutant prorenin for 6 h, cultured supernatant acquired the ability to generate angiotensin I (ANG I) from angiotensinogen, indicating both prorenins were activated. Small interfering RNA (siRNA) against the (p)RR blocked their activation. Furthermore, either native or mutant rat prorenin at 10−7 M alone similarly and significantly induced transforming growth factor-β1, plasminogen activator inhibitor-1 (PAI-1), and fibronectin mRNA expression, and these effects were blocked by (p)RR siRNA, but not by the ANG II receptor antagonist, saralasin. When angiotensinogen was also added to cultured MCs with inactive native or mutant prorenin, PAI-1 and fibronectin were further increased significantly compared with prorenin or mutant prorenin alone. This effect was blocked partially by treatment with (p)RR siRNA or saralasin. We conclude that prorenin binds the (p)RR on renal MCs and is activated nonproteolytically. This activation leads to increased expression of PAI-1 and transforming growth factor-β1 via ANG II-independent and ANG II-dependent mechanisms. These data provide a mechanism by which elevated prorenin levels in diabetes may play a role in the development of diabetic nephropathy.


2002 ◽  
Vol 88 (10) ◽  
pp. 639-643 ◽  
Author(s):  
Ramón Montes ◽  
Pablo Rodríguez-Whilhelmi ◽  
Verónica Hurtado ◽  
Akihiro Matsukawa ◽  
Marta Montes ◽  
...  

SummaryThe plasminogen activator inhibitor-1 (PAI-1)-dependent fibrinolytic inhibition occurring in endotoxemia contributes to disseminated intravascular coagulation (DIC). Previous findings suggest that tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) are responsible for the increase in the level of PAI-1. These observations usually arose from mild endotoxemia models. We analyzed the effect of FR167653, an inhibitor of the TNF-α/IL-1β production, on the PAI-1 levels in rabbits given endotoxin at a dose sufficient to induce DIC: the steep plasma PAI-1 increase was not attenuated by FR167653, in spite of achieving efficient inhibition of the TNF-α production. No IL-1β was detected during endotoxemia. These results suggest that PAI-1 increase might be independent of TNF-α and IL-1β. If these findings applied to humans, therapeutic intervention directing these cytokines would not be useful for the treatment of fibrinolysis in patients with severe sepsis.


Blood ◽  
2010 ◽  
Vol 115 (10) ◽  
pp. 2038-2047 ◽  
Author(s):  
Zhi Xu ◽  
Francis J. Castellino ◽  
Victoria A. Ploplis

Abstract Although the involvement of plasminogen activator inhibitor-1 (PAI-1) in fibrotic diseases is well documented, its role in cardiac fibrosis remains controversial. The goal of this study was to determine the effect of a PAI-1 deficiency (PAI-1−/−) on the spontaneous development of cardiac fibrosis. PAI-1−/− mice developed pervasive cardiac fibrosis spontaneously with aging, and these mice displayed progressively distorted cardiac architecture and markedly reduced cardiac function. To mechanistically elucidate the role of PAI-1 in cardiac fibrosis, 12-week-old mice were chosen to study the biologic events leading to fibrosis. Although fibrosis was not observed at this early age, PAI-1−/− hearts presented with enhanced inflammation, along with increased microvascular permeability and hemorrhage. A potent fibrogenic cytokine, transforming growth factor-β (TGF-β), was markedly enhanced in PAI-1−/− heart tissue. Furthermore, the expression levels of several relevant proteases associated with tissue remodeling were significantly enhanced in PAI-1−/− hearts. These results suggest that PAI-1 is cardioprotective, and functions in maintaining normal microvasculature integrity. Microvascular leakage in PAI-1−/− hearts may provoke inflammation, and predispose these mice to cardiac fibrosis. Therefore, a PAI-1 deficiency contributes to the development of cardiac fibrosis by increasing vascular permeability, exacerbating local inflammation, and increasing extracellular matrix remodeling, an environment conducive to accelerated fibrosis.


Author(s):  
Theresia Indah Budhy ◽  
Ira Arundina ◽  
Meircurius Dwi Condro Surboyo ◽  
Anisa Nur Halimah

Abstract Objectives The purpose of this study is to analyze the effects of rice husk liquid smoke in Porphyromonas gingivalis-induced periodontitis in the inflammatory and proliferation marker such as nuclear factor kappa β (NF-kB), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), transforming growth factor-β (TGF-β), fibroblast growth factor 2 (FGF2), collagen type 1 (COL-1) expression, and the number of macrophages, lymphocytes, and fibroblasts. Materials and Methods Rice husk liquid smoke is obtained by the pyrolysis process. Porphyromonas gingivalis-induced periodontitis in 20 μL phosphate-buffered saline containing 1 × 109 CFU was injected into the lower anterior gingival sulcus of Wistar rats. The periodontitis was then treated with 20 μL/20 g body weight of rice husk liquid smoke once a day for 2 and 7 days, respectively. After treatment, the bone and lower anterior gingival sulcus were analyzed with immunohistochemistry and hematoxylin–eosin staining. Results The treatment of periodontitis with rice husk liquid smoke showed a lower NF-kB, TNF-α, and IL-6 expression and a higher TGF-β, FGF2, and COL-1 expression than the control after treatment for 2 and 7 days (p < 0.05), respectively. The number of macrophages and fibroblasts was also higher when compared with the control group (p < 0.05), but the number of lymphocytes was lower than the control (p < 0.05). Conclusion Rice husk liquid smoke showed its effects on Porphyromonas gingivalis-induced periodontitis with a decrease in inflammatory markers and an increase in proliferation markers. The development of a rice husk liquid smoke periodontitis treatment is promising.


Cancers ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 399 ◽  
Author(s):  
David Radke ◽  
Qi Ling ◽  
Robert Häsler ◽  
Gökhan Alp ◽  
Hendrik Ungefroren ◽  
...  

The accumulation of perturbations in signalling pathways resulting in an apoptosis-insensitive phenotype is largely responsible for the desperate prognosis of patients with pancreatic ductal adenocarcinoma (PDAC). Accumulating evidence suggests that the death receptors TRAIL-R1 and TRAIL-R2 play important roles in PDAC biology by acting as either tumour suppressors through induction of cell death or tumour promoters through induction of pro-inflammatory signalling, invasion and metastasis. TRAIL-R2 can also associate with nuclear proteins and alter the maturation of micro RNAs (miRs). By genome-wide miR profiling and quantitative PCR analyses we now demonstrate that knockdown of TRAIL-R1 in PDAC cells decreased the level of mature miR-370 and led to an increased abundance of the type II receptor for transforming growth factor β (TGFβ). Transfection of cells with an artificial miR-370-3p decreased the levels of TGFβ-RII. We further show that transient expression of the miR-370 mimic decreased TGFβ1-induced expression of SERPINE1 encoding plasminogen activator-inhibitor 1 and partially relieved TGFβ1-induced growth inhibition. Moreover, stable TRAIL-R1 knockdown in Colo357 cells increased TGFβ1-induced SERPINE1 expression and this effect was partially reversed by transient expression of the miR-370 mimic. Finally, after transient knockdown of TRAIL-R1 in Panc1 cells there was a tendency towards enhanced activation of Smad2 and JNK1/2 signalling by exogenous TGFβ1. Taken together, our study reveals that TRAIL-R1 through regulation of miR-370 can decrease the sensitivity of PDAC cells to TGFβ and therefore represents a potential tumour suppressor in late-stage PDAC.


2001 ◽  
Vol 90 (1) ◽  
pp. 90-98 ◽  
Author(s):  
Jeffrey D. Hasday ◽  
Douglas Bannerman ◽  
Sirhan Sakarya ◽  
Alan S. Cross ◽  
Ishwar S. Singh ◽  
...  

Fever is an important regulator of inflammation that modifies expression and bioactivity of cytokines, including tumor necrosis factor (TNF)-α. Pulmonary vascular endothelium is an important target of TNF-α during the systemic inflammatory response. In this study, we analyzed the effect of a febrile range temperature (39.5°C) on TNF-α-stimulated changes in endothelial barrier function, capacity for neutrophil binding and transendothelial migration (TEM), and cytokine secretion in human pulmonary artery endothelial cells (EC). Permeability for [14C]BSA tracer was increased by treatment with TNF-α, and this effect was augmented by incubating EC at 39.5°C. Treating EC with 2.5 U/ml TNF-α stimulated an increase in subsequent neutrophil adherence and TEM. Incubating EC at 39.5°C caused a 30% increase in TEM but did not modify the enhancement of neutrophil adherence or TEM by TNF-α treatment. Analysis of cytokine expression in EC cultures exposed to TNF-α at either 37° or 39.5°C revealed three patterns of temperature and TNF-α responsiveness. Granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin (IL)-8 were not detectable in untreated EC but were increased after TNF-α exposure, and this increase was enhanced at 39.5°C. IL-6 expression was also increased with TNF-α exposure, but IL-6 expression was lower in 39.5°C EC cultures. Transforming growth factor-β1was constitutively expressed, and its expression was not influenced either by TNF-α or exposure to 39.5°C. These data demonstrate that clinically relevant shifts in body temperature might cause important changes in the effects of proinflammatory cytokines on the endothelium.


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