scholarly journals p52(PAI-1) and actin expression in butyrate-induced flat revertants of v-ras-transformed rat kidney cells

1991 ◽  
Vol 279 (3) ◽  
pp. 883-890 ◽  
Author(s):  
P J Higgins ◽  
M P Ryan

Flat revertants of v-ras-transformed (KNRK) rat kidney cells, which express elevated levels of p21ras protein, were generated to high efficiencies with sodium butyrate (NaB). Overall protein synthesis in revertants was not different from parental cells, although changes were evident in expression and distribution of specific microfilament-associated cytoskeletal proteins. Quantitative two-dimensional electrophoresis revealed revertant-associated 3-4-fold increases in cytoskeletal deposition of the microfilament-associated proteins gelsolin and vinculin correlating with microfilament reorganization and focal-contact formation respectively. Similar increases in actin content were evident at both the total-cellular- and cytoskeletal-associated-protein levels. In contrast, intermediate-filament family elements (vimentin, lamins) remained unaltered. The only unique protein resolved in flat revertants was p52, a 52 kDa extracellular-matrix-associated protein previously identified as plasminogen-activator inhibitor type 1 (PAI-1). p52(PAI-1) expression was induced early during generation of the revertant phenotype and preceded development of focal-contact structures. NaB-induced p52(PAI-1) synthesis and generation of early morphological reversion in KNRK cells required ongoing RNA synthesis, since exposure to actinomycin D before addition of NaB inhibited both events. p52(PAI-1) induction by NaB was regulated at the level of mRNA abundance; in contrast, actin mRNA levels were the same in parental and revertant cells, suggesting that the increased actin content which typified the revertant phenotype was due to augmented actin microfilament stability.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1146-1146
Author(s):  
Keiko Maruyama ◽  
Eriko Morishita ◽  
Shigeki Ohtake ◽  
Akihiro Yachie ◽  
Shinji Nakao

Abstract Abstract 1146 Background and purpose: Heme oxygenase-1 (HO-1) is a cytoprotective and anti-inflammatory protein that catalyzes the conversion of heme into biliverdin, free iron, and carbon monoxide (CO). HO-1 is rapidly induced by various oxidative stresses and inflammation, thereby playing an important role in the self defence system. Recently, Yachie, et al. reported the first human case of HO-1 deficiency. This patient showed prominent signs of intravascular hemolysis, endothelial cell injury, and abnormalities in the coagulation / fibrinolysis system, suggesting the involvement of HO-1 or HO-1 products, such as CO, regulation of coagulation / fibrinolysis system. The current study examined whether tricarbonyldichlororuthenium (II) dimer (CORM-2), which liberated CO in the presence of dimethyl sulfoxide (DMSO), modulates the expression of tissue factor (TF), plasminogen activator inhibitor type 1 (PAI-1) and thrombomodulin (TM) in human umbilical vein endothelial cells (HUVECs). Methods: HUVECs were pretreated with CORM-2 at the concentration of 50 μM for 3h, washed and stimulated with tumor necrosis factor-α(TNF-α, 10 ng/ml) for additional 2 or 5h. The mRNA and protein levels of TF, PAI-1 and TM in the cultured HUVECs were determined by real-time reverse transcriptase polymerase chain reaction and Western blotting. To determine whether CORM-2 affects the MAPK signaling pathways, the phosphorylation of p38 mitogen-activated protein kinase (p38MAPK) and extracellular signal-regulated kinase1/2 (ERK1/2) in the HUVECs were analyzed with Western blotting. Results: After TNF-α stimulation, TF mRNA levels were approximately 6-fold and PAI-1 mRNA levels were approximately 8-fold increased, and TM mRNA levels were decreased by 20% compared to the control. Similarly to the mRNA expression, TF and PAI-1 protein levels were increased while the TM protein level was decreased. On the other hand, pretreatment of HUVECs with CORM-2 significantly decreased TF mRNA levels (approximately 80% suppression), and PAI-1 mRNA levels (approximately 90% suppression) while increased TM mRNA levels by 3-fold as compared to the TNF-α-stimulated group (p<0.05; Figure 1). Similarly, the pretreatment with CORM-2 inhibited TNF-α-induced TF and PAI-1 protein up-regulation and TM protein down-regulation. CORM-2 inhibited TNF-α-induced activation of p38MAPK and ERK1/2 by 50% compared to the control. Conclusions: These results indicate that CO liberated by CORM-2 suppresses the TNF-α-induced TF and PAI-1 up-regulation and prevents the TNF-α-induced TM down-regulation in HUVECs via MAPK signaling pathways. Thus, the modulation of endothelial function by CO may offer a novel antithrombotic option for treatment of the hypercoagulable state associated with inflammation. Disclosures: No relevant conflicts of interest to declare.


1992 ◽  
Vol 284 (2) ◽  
pp. 433-439 ◽  
Author(s):  
P J Higgins ◽  
M P Ryan

Cell shape profoundly affects cellular metabolic activity, protein and nucleic acid synthesis, and cytoskeletal organization. To examine the influence of cell shape on protein expression, normal rat kidney (NRK) cells were exposed to the microfilament-disrupting drug cytochalasin D (CD), labelled with [35S]methionine, and newly synthesized cellular and cytoskeletal proteins examined by two-dimensional gel electrophoresis. CD produced dramatic changes in cell shape (from a flat to round phenotype) with concomitant 3-7-fold increases in the cellular content and cytoskeletal deposition of the microfilament-associated proteins actin, alpha-actinin, and tropomyosin isoform 1. Augmented actin protein content in NRK/CD cells was paralleled by a corresponding increase in actin mRNA abundance and was inhibited by prior addition of actinomycin D. A detergent-insoluble protein of 52 kDa was also detected at high levels in the cytoskeletal fraction of NRK/CD cells. Two-dimensional electrophoretic mapping of total cellular and cytoskeletal proteins revealed this 52 kDa protein to be the previously described glycoprotein p52 [Higgins & Ryan (1989) Biochem. J. 257, 173-182]. By using electrophoretic and immunochemical criteria, p52 was identified as plasminogen-activator inhibitor type-1 (PAI-1). Like actin, CD-induced p52(PAI-1) synthesis, cellular content, and partitioning to the detergent-insoluble cytoskeletal compartment reflected a corresponding increase in p52(PAI-1) mRNA. Such induction was similarly inhibited by actinomycin D. p52(PAI-1) expression in the NRK-cell system is thus responsive to CD-mediated shape changes and requires ongoing RNA synthesis for its induction. Differential extraction of detached cell bodies and the substrate-adherent ‘remnant’ fraction of NRK/CD cultures, furthermore, indicated that p52(PAI-1) was not an intrinsic internal cytoskeletal element but, rather, selectively localized to the extracellular residue. p52(PAI-1) retained its detergent-insoluble characteristics even in this isolated ‘remnant’ fraction, where it was also the predominant protein species resolved.


2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Zhong-Hui Wang ◽  
Wei-Ying Ren ◽  
Lei Zhu ◽  
Li-Juan Hu

Background. The mechanisms by which plasminogen activator inhibitor-1 (PAI-1) regulates inflammation, especially in acute respiratory distress syndrome (ARDS), are largely unknown.Objective. To assess the relationship between PAI-1 and autophagy in inflammatory reactions induced by LPS in rat NR8383 cells.Methods. ELISA was used to assess the amounts of TNF-α, IL-1β, and PAI-1 in cell culture supernatants; TLR4, MyD88, PAI-1, LC3, Beclin1, and mTOR protein and mRNA levels were determined by western blot and quantitative RT-PCR, respectively; western blot was used to determine NF-κB protein levels. To further evaluate the role of PAI-1, the PAI-1 gene was downregulated and overexpressed using the siRNA transfection technology and the pCDH-PAI-1, respectively. Finally, the GFP Positive Expression Rate Method was used to determine the rate of GFP-LC3 positive NR8383 cells.Results. In LPS-induced NR8383 cells, TNF-α, IL-1β, and PAI-1 expression levels increased remarkably. Upon PAI-1 knockdown, TNF-α, IL-1β, PAI-1, TLR4, MyD88, NF-κB, LC3, and Beclin1 levels were decreased, while mTOR increased. Conversely, overexpression of PAI-1 resulted in increased amounts of TNF-α, IL-1β, PAI-1, TLR4, MyD88, NF-κB, LC3, and Beclin1. However, no significant change was observed in mTOR expression.Conclusions.In NR8383 cells, PAI-1 contributes in the regulation of LPS-induced inflammation, likely by promoting autophagy.


2007 ◽  
Vol 85 (2) ◽  
pp. 246-251 ◽  
Author(s):  
Hong Jin ◽  
Jijin Lin ◽  
Lu Fu ◽  
Yi-Fang Mei ◽  
Geng Peng ◽  
...  

There is a striking gender difference in atherosclerotic vascular disease. For decades, testosterone was considered detrimental to the cardiovascular system. Recent studies, however, have presented some alternative results. The aim of this study was to evaluate the effect of testosterone, using physiological and supraphysiological concentrations, on antigen and mRNA levels of tissue plasminogen activator (tPA), plasminogen activator inhibitor type 1 (PAI-1), and tissue factor pathway inhibitor (TFPI) released by human umbilical vein endothelial cells and to investigate the cellular mechanism. Cells within 2–3 passages were cultured in 25 cm2 flasks or plated onto 96-well plates with a density of about 1 × 105 cells/mL as recommended. The cells were incubated in the presence or absence of testosterone (3, 30, 3 × 103, 3 × 104 nmol/L) for 48 h. Levels of tPA, PAI-1, and TFPI antigen were assayed with ELISA kits. Reverse transcriptase PCR was carried out to detect tPA, PAI-1, and TFPI mRNA levels. Cells were incubated in androgen-receptor antagonist (flutamide 10 µmol/L) or aromatase inhibitor (aminoglutethimide 50 µmol/L) for 3 h, and then the experiments were repeated. Testosterone at a physiologic concentration (30 nmol/L) increased the antigen levels of tPA and TFPI significantly (P < 0.05). However, tPA and TFPI levels were markedly reduced (P < 0.05) at a larger dose (3 × 104 nmol/L). On the other hand, PAI-1 antigen levels decreased significantly at the testosterone concentrations ranging from 3 to 3 × 104 nmol/L (P < 0.05). The change in the levels of tPA and TFPI were reflected in the corresponding change in mRNA levels. Flutamide attenuated the effect of testosterone at physiological concentration (30 nmol/L). The results demonstrated that testosterone at physiological concentrations may have a beneficial influence on the haemostatic system through enhancement of anticoagulant activity, resulting from stimulation of TFPI and tPA expression and inhibition of PAI-1 secretion by the endothelium.


2011 ◽  
Vol 300 (5) ◽  
pp. F1244-F1254 ◽  
Author(s):  
Jesús M. López-Guisa ◽  
Allen C. Rassa ◽  
Xiaohe Cai ◽  
Sarah J. Collins ◽  
Allison A. Eddy

Vitronectin (Vtn) is a glycoprotein found in normal serum and pathological extracellular matrix. Given its known interactions with plasminogen activator inhibitor-1 (PAI-1) and Vtn cellular receptors, especially αvβ3 integrin and the urokinase receptor (uPAR), this study was designed to investigate its role in renal fibrogenesis in the mouse model of unilateral ureteral obstruction (UUO). Kidney Vtn mRNA levels were increased ×1.8–5.1 and Vtn protein levels ×1.9–3 on days 7, 14, and 21 after UUO compared with sham kidney levels. Groups of age-matched C57BL/6 wild-type (Vtn+/+) and Vtn−/− mice ( n = 10–11/group) were killed 7, 14, or 21 days after UUO. Absence of Vtn resulted in the following significant differences, but only on day 14: fewer αSMA+ interstitial myofibroblasts (×0.53), lower procollagen III mRNA levels (×0.41), lower PAI-1 protein (×0.23), higher uPA activity (×1.1), and lower αv protein (×0.32). The number of CD68+ macrophages did not differ between the genotypes. Despite these transient differences on day 14, the absence of Vtn had no effect on fibrosis severity based on both picrosirius red-positive interstitial area and total kidney collagen measured by the hydroxyproline assay. These findings suggest that despite significant interstitial Vtn deposition in the UUO model of chronic kidney disease, its fibrogenic role is either nonessential or redundant. These data are remarkable given Vtn's strong affinity for the potent fibrogenic molecule PAI-1.


1991 ◽  
Vol 66 (03) ◽  
pp. 310-314 ◽  
Author(s):  
David C Sane ◽  
Tammy L Moser ◽  
Charles S Greenberg

SummaryVitronectin (VN) stabilizes plasminogen activator inhibitor type 1 (PAI-1) activity and prevents the fibrin(ogen)-induced acceleration of plasminogen activation by t-PA. These antifibrinolytic activities as well as other functions are mediated by the glycosaminoglycan (GAG) binding domain of VN. Since the GAG binding region is rich in arginyl and lysyl residues, it is a potential target for enzymes such as plasmin. In this paper, the dose and time-dependent proteolysis of VN by plasmin is demonstrated. The addition of urokinase or streptokinase (200 units/ml) to plasma also produced proteolysis of VN. With minimal proteolysis, the 75 kDa band was degraded to a 62-65 kDa form of VN. This minimal proteolysis destroyed the binding of [3H]-heparin to VN and reversed the neutralization of heparin by VN.Thus, the plasmin-mediated proteolysis of the GAG binding activity of VN could destroy the antifibrinolytic activity of VN during physiologic conditions and during thrombolytic therapy. Furthermore, other functions of VN in complement and coagulation systems that are mediated by the GAG binding domain may be destroyed by plasmin proteolysis.


2009 ◽  
Vol 201 (1) ◽  
pp. 59-66 ◽  
Author(s):  
Hongbin Liu ◽  
Anthony E Dear ◽  
Lotte B Knudsen ◽  
Richard W Simpson

Glucagon-like peptide-1 (GLP-1) administration attenuates endothelial cell dysfunction in diabetic patients and inhibits tumour necrosis factor α (TNF)-mediated plasminogen activator inhibitor type-1 (PAI-1) induction in human vascular endothelial cells. The short half-life of GLP-1 mediated via degradation by the enzyme dipeptidyl peptidase 4 mandates the clinical use of long-acting GLP-1 analogues. The effects of a long-acting GLP-1 analogue on PAI-1 and vascular adhesion molecule expression in vascular endothelial cells are unknown. In this report, we demonstrate for the first time that the treatment with liraglutide, a long-acting GLP-1 analogue, inhibited TNF or hyperglycaemia-mediated induction of PAI-1, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 mRNA and protein expression in a human vascular endothelial cell line. In addition, treatment attenuated TNF- or hyperglycaemia-mediated induction of the orphan nuclear receptor Nur77 mRNA expression. Taken together, these observations indicate that liraglutide inhibits TNF- or glucose-mediated induction of PAI-1 and vascular adhesion molecule expression, and this effect may involve the modulation of NUR77. These effects suggest that liraglutide may potentially improve the endothelial cell dysfunction associated with premature atherosclerosis identified in type 2 diabetic patients.


Author(s):  
Tae Ito ◽  
Yuko Suzuki ◽  
Hideto Sano ◽  
Naoki Honkura ◽  
Francis J Castellino ◽  
...  

Background: Details of the molecular interaction between tissue type plasminogen activator (tPA) and plasminogen activator inhibitor type-1 (PAI-1) remain unknown. Methods and Results: Three distinct forms of high molecular weight complexes are demonstrated. Two of the forms were detected by mass spectrometry. The high molecular mass detected by MALDI-TOF MS spectrometry was 107,029 Da, which corresponds to the sum of molecular masses of the intact tPA (65,320 Da) and the intact PAI-1 (42,416 Da). The lower molecular mass was 104,367 Da and is proposed to lack the C-terminal bait peptide of PAI-1 (calculated mass, 3,804 Da) which was detected as a 3,808 Da fragment. When the complex was analyzed by SDS-PAGE, only a single band was observed. However, after treatment by SDS and Triton X-100, two distinct forms of the complex with different mobilities were shown by SDS-PAGE. The higher molecular weight band demonstrated specific tPA activity on fibrin autography, whereas the lower molecular weight band did not. Peptide sequence analysis of these two bands, however, unexpectedly revealed the existence of the C-terminal cleavage peptide in both bands and its amount was less in the upper band. In the upper band, the sequences corresponding to the regions at the interface between two molecules in its Michaelis intermediate were diminished. Thus, these two bands corresponded to distinct nonacyl-enzyme complexes, wherein only the upper band liberated free tPA under the conditions employed. Conclusion: These data suggest that under physiological conditions a fraction of the tPA-PAI-1 population exists as non-acylated-enzyme inhibitor complex.


2003 ◽  
Vol 89 (05) ◽  
pp. 926-935 ◽  
Author(s):  
Utta Berchner-Pfannschmidt ◽  
Christoph Wotzlaw ◽  
Robbert Cool ◽  
Joachim Fandrey ◽  
Helmut Acker ◽  
...  

SummaryThe hypoxia-inducible transcription factor HIF-1 mediates upregulation of plasminogen activator inhibitor-1 (PAI-1) expression under hypoxia. Reactive oxygen species (ROS) have also been implicated in PAI-1 gene expression. However, the role of ROS in HIF-1-mediated regulation of PAI-1 is not clear. We therefore investigated the role of the GTPase Rac1 which modulates ROS production in the pathway leading to HIF-1 and PAI-1 induction.Overexpression of constitutively activated (RacG12V) or dominant-negative (RacT17N) Rac1 increased or decreased, respectively, ROS production. In RacG12V-expressing cells, PAI-1 mRNA levels as well as HIF-1α nuclear presence were reduced under normoxia and hypoxia whereas expression of RacT17N resulted in opposite effects. Treatment with the antioxidant pyrrolidinedithiocarbamate or coexpression of the redox factor-1 restored HIF-1 and PAI-1 promoter activity in RacG12V-cells. In contrast, NFκB activation was enhanced in RacG12V-cells, but abolished by RacT17N. Thus, these findings suggest a mechanism explaining modified fibrinolysis and tissue remodeling in an oxidized environment.


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