Plasminogen Activator Inhibitor-1 Expression Research Articles

PAI-1 is a potential transcriptional silencer that supports bladder cancer cell activity

The extracellular activity of Plasminogen activator inhibitor-1 (PAI-1) is well described, acting as an inhibitor of tissue plasminogen activator and urokinase-type plasminogen activator, impacting fibrinolysis. Recent studies have revealed a pro-tumorigenic role of PAI-1 in human cancers, via the regulation of angiogenesis and tumor cell survival. In this study, immunohistochemical staining of 939 human bladder cancer specimens showed that PAI-1 expression levels correlated with tumor grade, tumor stage and overall survival. The typical subcellular localization of PAI-1 is cytoplasmic, but in approximately a quarter of the cases, PAI-1 was observed to be localized to both the tumor cell cytoplasm and the nucleus. To investigate the potential function of nuclear PAI-1 in tumor biology we applied chromatin immunoprecipitation (ChIP)-sequencing, gene expression profiling, and rapid immunoprecipitation mass spectrometry to a pair of bladder cancer cell lines. ChIP-sequencing revealed that PAI-1 can bind DNA at distal intergenic regions, suggesting a role as a transcriptional coregulator. The downregulation of PAI-1 in bladder cancer cell lines caused the upregulation of numerous genes, and the integration of ChIP-sequence and RNA-sequence data identified 57 candidate genes subject to PAI-1 regulation. Taken together, the data suggest that nuclear PAI-1 can influence gene expression programs and support malignancy.

Piperlongumin Improves Survival in the Mouse Model of Sepsis: Effect on Coagulation Factors and Lung Inflammation.

Excessive inflammation and coagulation contribute to high morbidity and mortality in sepsis. Many studies have indicated the role of piperlongumine (PL) in anti-inflammation, but its effect on coagulation remains uncertain. Here, we explore whether PL could moderate coagulation indicators and alleviate lung inflammation during sepsis. RAW264.7 cells were induced by lipopolysaccharide (LPS) and treated with PL. Inflammatory and coagulation indicators, cell function and signaling, were evaluated in cells. Cecal ligation and puncture (CLP) mice were treated with PL by gavage. The harvested lungs and plasma were used to assess inflammation and coagulation indicators. As a result, PL increased the survival rate and reduced the concentrations of tissue factor (TF), plasminogen activator inhibitor 1 (PAI-1), thrombin-antithrombin complex (TAT), D-dimer, interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α in CLP mice, with fibrinogen in reverse. Moreover, the PL alleviated inflammation, fibrin deposition, and lung injury in the lungs of CLP mice. In vitro, PL downregulated the expression of TF, PAI-1, IL-6, TNF-α, and IL-1β in RAW264.7 cells induced by LPS. Furthermore, PL inhibited the phosphorylation of the AKT/mTOR signaling pathway’s key proteins and suppressed the nuclear translocation of p-STAT3 in LPS-stimulated RAW264.7 cells. In conclusion, this study suggests that PL may modulate coagulation indicators and improve lung inflammation through AKT/mTOR signaling pathway in sepsis.

Vitronectin and Its Interaction with PAI-1 Suggests a Functional Link to Vascular Changes in AMD Pathobiology.

The pathogenesis of age-related macular degeneration (AMD), a frequent disorder of the central retina, is incompletely understood. Genome-wide association studies (GWAS) suggest a strong contribution of genomic variation in AMD susceptibility. Nevertheless, little is known about biological mechanisms of the disease. We reported previously that the AMD-associated polymorphism rs704C > T in the vitronectin (VTN) gene influences protein expression and functional aspects of encoded vitronectin, a human blood and extracellular matrix (ECM) protein. Here, we refined the association of rs704 with AMD in 16,144 cases and 17,832 controls and noted that rs704 is carried exclusively by the neovascular AMD subtype. Interaction studies demonstrate that rs704 affects the ability of vitronectin to bind the angiogenic regulator plasminogen activator inhibitor 1 (PAI-1) but has no influence on stabilizing its active state. Western blot analysis and confocal imaging reveal a strong enrichment of PAI-1 in the ECM of cultured endothelial cells and RPE cell line ARPE-19 exposed to vitronectin. Large-scale gene expression of VTN and PAI-1 showed positive correlations and a statistically significant increase in human retinal and blood tissues aged 60 years and older. Our results suggest a mechanism by which the AMD-associated rs704 variant in combination with ageing may contribute to the vascular complications in AMD.

The inhibitory effects of Dulaglutide on cellular senescence against high glucose in human retinal endothelial cells

Diabetic nephropathy is one of the most important chronic microvascular complications of diabetes, and its main feature is diabetic glomerulosclerosis. Endothelial sirtuin 1 (SIRT1) expression is related to aging, and reducing SIRT1 expression promotes endothelial cell aging. Plasminogen activator inhibitor-1 (PAI-1) can be synthesized in a variety of cells, such as endothelial cells. Dulaglutide is a glucagon-like peptide-1 (GLP-1) drug, and it can activate the GLP-1 receptor and promote the conversion of intracellular adenosine triphosphate to adenylate cyclase, thereby activating phosphokinase A, and regulating blood glucose levels effectively in the body. We analyzed the effects of Dulaglutide on inhibiting cell senescence by studying the effects of its different concentrations on telomerase activity and senescence-related gene expression. Our results suggest that Dulaglutide can alleviate high-glucose-induced oxidative stress in human retinal endothelial cells by restoring the expressions of SIRT1 and endothelial nitric oxide synthase (eNOS), thereby inhibiting the expression of PAI-1, and restoring telomerase activity. This suggests that the activity of retinal endothelial cells can be controlled by regulating the expression of SIRT1, so as to achieve the effect of treating diabetic retinopathy.

PAI-1: A Major Player in the Vascular Dysfunction in Obstructive Sleep Apnea?

Obstructive sleep apnea is a chronic and prevalent condition that is associated with endothelial dysfunction, atherosclerosis, and imposes excess overall cardiovascular risk and mortality. Despite its high prevalence and the susceptibility of CVD patients to OSA-mediated stressors, OSA is still under-recognized and untreated in cardiovascular practice. Moreover, conventional OSA treatments have yielded either controversial or disappointing results in terms of protection against CVD, prompting the need for the identification of additional mechanisms and associated adjuvant therapies. Plasminogen activator inhibitor-1 (PAI-1), the primary inhibitor of tissue-type plasminogen activator (tPA) and urinary-type plasminogen activator (uPA), is a key regulator of fibrinolysis and cell migration. Indeed, elevated PAI-1 expression is associated with major cardiovascular adverse events that have been attributed to its antifibrinolytic activity. However, extensive evidence indicates that PAI-1 can induce endothelial dysfunction and atherosclerosis through complex interactions within the vasculature in an antifibrinolytic-independent matter. Elevated PAI-1 levels have been reported in OSA patients. However, the impact of PAI-1 on OSA-induced CVD has not been addressed to date. Here, we provide a comprehensive review on the mechanisms by which OSA and its most detrimental perturbation, intermittent hypoxia (IH), can enhance the transcription of PAI-1. We also propose causal pathways by which PAI-1 can promote atherosclerosis in OSA, thereby identifying PAI-1 as a potential therapeutic target in OSA-induced CVD.

Loureirin B Alleviates Myocardial Ischemia/Reperfusion Injury via Inhibiting PAI-1/TGF-β1/Smad Signaling Pathway.

Myocardial ischemia/reperfusion (MI/R) injury is a common clinical problem after myocardial infarction without effective therapy. Loureirin B (LrB) is a kind of flavonoid with anti-inflammatory and antifibrotic activities. However, the effect of LrB on MI/R and its underlying mechanism remains elusive. In the present study, a mouse model of MI/R was established by coronary artery occlusion. Administration of LrB (0.5 mg/kg or 1 mg/kg) for 4 weeks effectively improved left ventricular (LV) function and reduced myocardial infarction in MI/R mice. MI/R-induced expression of IL-6, TNF-α, and IL-1β in the hearts was reduced by LrB treatment. Histological analysis showed that LrB attenuated myocardial collagen deposition. LrB downregulated fibronectin, collagen I, collagen III, and α-SMA expression. Notably, LrB inhibited the expression of profibrotic plasminogen activator inhibitor-1 (PAI-1), transforming growth factor (TGF)-β1, TGF-β1R, and p-Smad2/3. Consistently, LrB inhibited the activation of TGF-β1/Smad signaling pathway and the expression of fibrosis-related proteins in angiotensin (Ang) II-treated cardiac fibroblasts (CFs). Overexpression of PAI-1 abolished the effects of LrB on Ang II-treated CFs, suggesting that LrB may function through regulating PAI-1. These results indicated that LrB may alleviate MI/R-induced myocardial fibrosis by inhibiting PAI-1/TGF-β1/Smad signaling pathway. Thus, LrB may be a potential drug in the treatment of MI/R injury.

Clostridium butyricum RH2 Alleviates Chronic Foot Shock Stress-Induced Behavioral Deficits in Rats via PAI-1.

Recent investigations have demonstrated that the chronic stress-induced behavioral disorders can be ameliorated by probiotics including Clostridium butyricum (C. butyricum) via the gut-brain-axis. However, the molecular mechanisms underlying the beneficial effects of C. butyricum on brain remain largely unknown. Here, we investigated whether chronic foot shock stress (CFSS) paradigm used for a hypertensive animal model could induce mood disorders such as anxiety, depression and cognitive impairments. Then, we assessed the impact of C. butyricum RH2 on the behavior disorders and neurobiological alterations in the hippocampus. Male Sprague-Dawley (SD) rats received intermittent electric shocks for consecutive 14 days and were treated with C. butyricum RH2 for 17 days. Anxiety- or depression-like behaviors were evaluated by open field test (OFT), and elevated plus maze (EPM). The Morris water maze test (MWM) was used to evaluate the cognitive functions. CFSS intervention led to mild anxiety- or depression-like behavior or cognitive impairment and C. butyricum RH2 treatment reversed the CFSS-induced symptoms. The serum ACTH or CORT was increased following CFSS but was completely reversed by C. butyricum RH2 treatment. In the hippocampus of CFSS rats, the expressions of BDNF and TrkB were downregulated but proBDNF and P75NTR were upregulated. These expression changes were partially reversed by C. butyricum RH2, suggesting a mode of action on BDNF and proBDNF balance. CFSS exposure resulted in downregulation of tissue-type plasminogen activator (tPA) but upregulation of plasminogen activator inhibitor 1(PAI-1), which could contribute to the decrease in BDNF by reduced conversion from proBDNF to BDNF in the hippocampus. C. butyricum RH2 treatment reversed the upregulated PAI-1 but not the downregulated tPA, which was in parallel with the amelioration of behavioral abnormalities, suggesting a novel tPA independent mechanism for PAI-1 action. Our results demonstrate for the first time that C. butyricum RH2 attenuates stress-induced behavior disorders via inhibiting the expression of brain PAI-1.

PAI-1 is a vascular cell-specific HIF-2-dependent angiogenic factor that promotes retinal neovascularization in diabetic patients.

For patients with proliferative diabetic retinopathy (PDR) who do not respond adequately to pan-retinal laser photocoagulation (PRP) or anti–vascular endothelial growth factor (VEGF) therapies, we hypothesized that vascular cells within neovascular tissue secrete autocrine/paracrine angiogenic factors that promote disease progression. To identify these factors, we performed multiplex ELISA angiogenesis arrays on aqueous fluid from PDR patients who responded inadequately to anti-VEGF therapy and/or PRP and identified plasminogen activator inhibitor-1 (PAI-1). PAI-1 expression was increased in vitreous biopsies and neovascular tissue from PDR eyes, limited to retinal vascular cells, regulated by the transcription factor hypoxia-inducible factor (HIF)-2α, and necessary and sufficient to stimulate angiogenesis. Using a pharmacologic inhibitor of HIF-2α (PT-2385) or nanoparticle-mediated RNA interference targeting Pai1, we demonstrate that the HIF-2α/PAI-1 axis is necessary for the development of retinal neovascularization in mice. These results suggest that targeting HIF-2α/PAI-1 will be an effective adjunct therapy for the treatment of PDR patients.

The Effects and Underlying Mechanisms of Hepatitis B Virus X Gene Mutants on the Development of Hepatocellular Carcinoma.

We aimed to elucidate the mechanism by which hepatitis B virus X (HBx) mutations increase the occurrence of hepatocellular carcinoma (HCC) and identify novel putative therapeutic targets. Wild-type HBx (WT-HBx) and four HBx mutants (M1, A1762T/G1764A; M2, T1674G+T1753C+A1762T/G1764A; M3, C1653T+T1674G+A1762T/G1764A; and Ct-HBx, carboxylic acid-terminal truncated HBx) were delivered into Sleeping Beauty (SB) mouse models. The HCC incidence was higher in the M3-HBx- and Ct-HBx-injected SB mice. M3-HBx had a stronger capacity of upregulating inflammatory cytokines than other HBx variants. Ectopic expression of M3-HBx and Ct-HBx significantly increased proliferation and S phase proportion of HepG2 and HeLa cells, compared to WT-HBx. Plasminogen activator inhibitor-1 (PAI1) and cell division cycle 20 (CDC20) were identified as novel effectors by cDNA microarray analysis. M3-HBx and Ct-HBx significantly upregulated the expression of PAI1 and CDC20 in HepG2 and HeLa cells as well as the livers of SB mice. Silencing PAI1 attenuated the effects of M3-HBx and Ct-HBx on the growth of HepG2 and HeLa cells. PAI1, an important player bridging the HBx mutants and HCC, should be a promising candidate as a prognostic biomarker and therapeutic target in HBV-related HCC.

Features of plasminogen activator inhibitor-1 synthesis by local fat depots of different localization in cardiovascular diseases

Aim. To determine the features of expression and secretion of plasminogen activator inhibitor-1 (PAI-1) by subcutaneous, epicardial and perivascular adipocytes depending on the complexity of coronary artery disease (CAD).Material and methods. The study included 86 patients with CAD, including 35 with moderate atherosclerotic lesions of the coronary arteries (CA) (SYNTAX Score ≤22), 22 with severe (SYNTAX Score of 23-31 pints), 29 with extremely severe (SYNTAX Score ≥32). As a comparison group, 52 patients with heart defects were examined. During an elective surgical intervention, adipose tissue (AT) samples were obtained for subsequent cultivation and determination of PAI-1 gene expression and PAI-1 secretion in AT supernatants of various localizations. Statistical analysis was performed using Statistica 10.0.Results. In CAD, PAI-1 production in all three types of AT and plasma PAI-1 concentration were increased compared with patients with heart defects. Epicardial AT (EAT) in CAD was characterized by the maximum levels of expression and secretion of PAI-1 relative to patients with heart defects and subcutaneous and perivascular (PVAT) fat depots. Moderate coronary involvement (adipose tissue <22) is characterized by the lowest expression and secretion of PAI-1 in all types of AT and plasma concentration of PAI-1. Direct correlations of PAI-1 expression and secretion in EAT and PVAT and plasma PAI-1 level with its secretion in EAT in patients with CAD and heart defects were revealed. A direct correlation between the plasma level of PAI-1 and its secretion in PVAT was found only in CAD.Conclusion. In CAD, there is not only an increase in the plasma PAI-1 level, but also an increase in the expression of PAI-1 gene and the secretion of PAI-1 in all three types of AT compared with patients with heart defects. PAI-1 expression and secretion in EAT, PAI-1 plasma level, and age are predictors of severe/extremely severe coronary involvement in CAD.

Features of plasminogen activator inhibitor-1 synthesis by local fat depots of different localization in cardiovascular diseases

Aim. To determine the features of expression and secretion of plasminogen activator inhibitor-1 (PAI-1) by subcutaneous, epicardial and perivascular adipocytes depending on the complexity of coronary artery disease (CAD).Material and methods. The study included 86 patients with CAD, including 35 with moderate atherosclerotic lesions of the coronary arteries (CA) (SYNTAX Score ≤22), 22 with severe (SYNTAX Score of 23-31 pints), 29 with extremely severe (SYNTAX Score ≥32). As a comparison group, 52 patients with heart defects were examined. During an elective surgical intervention, adipose tissue (AT) samples were obtained for subsequent cultivation and determination of PAI-1 gene expression and PAI-1 secretion in AT supernatants of various localizations. Statistical analysis was performed using Statistica 10.0.Results. In CAD, PAI-1 production in all three types of AT and plasma PAI-1 concentration were increased compared with patients with heart defects. Epicardial AT (EAT) in CAD was characterized by the maximum levels of expression and secretion of PAI-1 relative to patients with heart defects and subcutaneous and perivascular (PVAT) fat depots. Moderate coronary involvement (adipose tissue <22) is characterized by the lowest expression and secretion of PAI-1 in all types of AT and plasma concentration of PAI-1. Direct correlations of PAI-1 expression and secretion in EAT and PVAT and plasma PAI-1 level with its secretion in EAT in patients with CAD and heart defects were revealed. A direct correlation between the plasma level of PAI-1 and its secretion in PVAT was found only in CAD.Conclusion. In CAD, there is not only an increase in the plasma PAI-1 level, but also an increase in the expression of PAI-1 gene and the secretion of PAI-1 in all three types of AT compared with patients with heart defects. PAI-1 expression and secretion in EAT, PAI-1 plasma level, and age are predictors of severe/extremely severe coronary involvement in CAD.

Eupafolin suppresses TGF-β1-induced human lung fibroblasts differentiation by downregulating β-catenin/plasminogen activator inhibitor-1 signaling

The anti-fibrotic activity of flavonoids from Eupatorium lindleyanum DC (EL) remains unclear. Our results showed that flavones from the plant exerted a stronger inhibitory effect than flavonols, and eupafolin presented the highest activity on lung fibroblast differentiation. Eupafolin weakened the levels of α-smooth muscle actin, the production of type I collagen and fibronectin, fibroblast-containing gel contractility and microfilament formation in transforming growth factor-β1-induced lung fibroblasts. Interestingly, eupafolin did not affect the canonical TGF-β/Smad2/3 pathway. Eupafolin reduced the levels of plasminogen activator inhibitor-1 (PAI-1), and pharmacological inhibition and knockdown of PAI-1 mitigated the differentiation of lung fibroblasts. Finally, β-catenin agonist, SKL2001, reversed the suppressive effect of eupafolin on PAI-1 expression and lung fibroblast differentiation. Therefore, flavones have higher anti-fibrotic activity than flavonols obtained from EL, and eupafolin suppressed lung fibroblast differentiation by downregulating β-catenin/PAI-1 signaling rather than the canonical TGF-β/Smad2/3 pathway.

Simvastatin Improves Outcomes of Endotoxin-induced Coagulopathy by Regulating Intestinal Microenvironment

ObjectiveThe systemic inflammatory response is regarded as the major cause of endotoxin-induced coagulopathy, which is a strong predictor of mortality in patients with severe sepsis. Simvastatin plays an important role in reducing inflammation. In addition, the gut has long been hypothesized to be the “motor” of critical illness, driving or aggravating sepsis by the increased intestinal permeability and bacterial translocation. Whether simvastatin plays a role in severe endotoxin-induced coagulopathy through the gut is unclear.MethodsIn this study, mice were administered 20 mg/kg simvastatin by gavage for 2 weeks and then intraperitoneally injected with 50 mg/kg endotoxin. Twelve h later, cytokine release, coagulation dysfunction, organ damage, and survival were assessed. Besides, the intestinal barrier, permeability, bacteria abundance, and translocation were evaluated.ResultsWe found that the severity of endotoxin-induced coagulopathy was significantly improved in simvastatin-pretreated mice, who showed attenuated depletion of coagulation factors and platelets, decreased plasminogen activator inhibitor-1 (PAI-1) expression, reduced organ fibrin deposition, and improved survival time. Also, simvastatin reduced epithelial apoptosis and improved intestinal barrier function by upregulating antimicrobial peptides, lysozyme, and mucins. Simvastatin increased Lactobacillales counts, while the lipopolysaccharide group showed increased Desulfovibrio and Mucispirillum, which can produce harmful toxins. Finally, the decreased intestinal permeability in the simvastatin group caused reduced bacterial translocation in the organs and blood, both in terms of quantity and species.ConclusionSimvastatin improves the prognosis of severe endotoxemia, and the intestinal microenvironment participates in this process.

Fibroblast growth factor-21 as a novel metabolic factor for regulating thrombotic homeostasis

Fibroblast growth factor-21 (FGF-21) performs a wide range of biological functions in organisms. Here, we report for the first time that FGF-21 suppresses thrombus formation with no notable risk of bleeding. Prophylactic and therapeutic administration of FGF-21 significantly improved the degree of vascular stenosis and reduced the thrombus area, volume and burden. We determined the antithrombotic mechanism of FGF-21, demonstrating that FGF-21 exhibits an anticoagulant effect by inhibiting the expression and activity of factor VII (FVII). FGF-21 exerts an antiplatelet effect by inhibiting platelet activation. FGF-21 enhances fibrinolysis by promoting tissue plasminogen activator (tPA) expression and activation, while inhibiting plasminogen activator inhibitor 1 (PAI-1) expression and activation. We further found that FGF-21 mediated the expression and activation of tPA and PAI-1 by regulating the ERK1/2 and TGF-β/Smad2 pathways, respectively. In addition, we found that FGF-21 inhibits the expression of inflammatory factors in thrombosis by regulating the NF-κB pathway.

Safinamide protects against amyloid β (Aβ)-induced oxidative stress and cellular senescence in M17 neuronal cells

ABSTRACT Alzheimer’s disease (AD) is a neurodegenerative disorder that is pathologically related to oxidative stress and cellular senescence. Safinamide is one of the clinically prescribed monoamine oxidase B (MAOB) inhibitors. It has been reported to possess therapeutic potential in neurological disorders. However, the therapeutic potential of safinamide in AD is still under investigation. In this study, we explored the effect of safinamide in amyloid (Aβ)1–42 oligomers-stimulated M17 neuronal cells. We established the in vitro model with M17 cells by treating them with 1 μM Aβ1-42 oligomers with or without safinamide (100 or 200 nM). The results show that safinamide ameliorated Aβ1-42 oligomers-induced oxidative stress in M17 cells as revealed by the decreased reactive oxygen species (ROS) production and reduced glutathione (GSH) content. Safinamide treatment significantly ameliorated senescence-associated-β-galactosidase (SA-β-gal)-positive cells and telomerase activity. Further, we show that safinamide treatment resulted in decreased mRNA and protein expressions of p21 and plasminogen activator inhibitor-1 (PAI-1). Moreover, silencing of Sirtuin1 (SIRT1) abolished the effects of safinamide on the mRNA levels of p21 and PAI-1, as well as SA-β-gal-positive cells in Aβ1-42 oligomers-induced M17 cells. In conclusion, we reveal that safinamide exerted a protective function on M17 cells from Aβ1-42 oligomers induction-caused oxidative stress and cellular senescence through SIRT1 signaling. These present results provide meaningful evidence that safinamide may be medically developed for the prevention and therapy of AD.

Effect of sera from lupus patients on the glomerular endothelial fibrinolysis system.

Dysregulation of the coagulation fibrinolysis system in resident glomerular cells is associated with the pathogenesis of lupus nephritis. However, the role of plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (tPA) in resident glomerular cells remains undetermined. We examined the expression of PAI-1 and tPA mRNA in cultured normal human glomerular endothelial cells (GECs) treated with serum from patients with systemic lupus erythematosus (SLE) using quantitative reverse transcription polymerase chain reactions. We determined the relationship between PAI-1/tPA mRNA expression and several clinical/laboratory parameters. Serum from 16 patients (nine patients with new-onset SLE and seven patients with stable SLE) was used in the study. Plasminogen activator inhibitor-1 and tPA mRNA expression was significantly higher in GECs treated with serum of patients with new-onset SLE than other groups. The PAI-1 and tPA mRNA levels were also significantly correlated in GECs treated with serum from patients with SLE. Interestingly, both PAI-1 and tPA mRNA levels in GECs were inversely correlated with serum C4 level and positively correlated with SLE disease activity. These results suggest that serum from patients with SLE may activate the fibrinolysis system in glomerulus, which may be involved in the pathogenesis of lupus nephritis.

Association between plasminogen activator inhibitor-1 gene polymorphisms and susceptibility to Parkinson's disease in Chinese patients.

Parkinson's disease (PD) is a neurodegenerative disease that usually leads to memory impairment, cognitive decline and dementia. Previous studies have reported that plasminogen activator inhibitor-1 (PAI-1) gene polymorphisms play important roles in cardiovascular diseases, obesity, inflammation and other diseases. However, the role of PAI-1 in the diagnosis of Parkinson's disease has not been reported so far. This study was a case-control study. This study included 131 PD patients and 97 healthy volunteers. polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to analyze the polymorphic loci of five different regions in PAI-1 gene (rs2227631, rs1799889, rs6092, rs2227694 and rs7242). 60 PD patients and 60 healthy volunteers were selected to detect the plasma PAI-1 concentration. The allele and genotype frequencies of SNPs were assessed using the SHEsis program. We found that GG genotype frequency and G allele frequency of rs2227631 was significantly higher in the PD patients. Statistically significant difference for rs1799889 could be observed in overdominant model. In subgroup analysis, a significant difference in genotype frequency distribution and allele frequency was found for rs2227631 and rs1799889 between early-onset PD group and the control group. For cognitive dysfunction, the subcomponent showed that GG genotype frequency and G allele frequency of rs2227631 was significantly higher in normal cognition group. The codominant model of rs1799889 was significantly different between the cognitive impairment group and the control group. In addition, the expression of PAI-1 in plasma of PD patients was significantly higher than that of controls, and further analysis showed that the expression of PAI-1 in patients with cognitive impairment was significantly higher than that in patients with cognitive normal. Our results indicate that the PAI-1 gene rs2227631 and rs1799889 polymorphisms were significantly associated with PD susceptibility in the Chinese Han population. PAI-1 has the potential to become a new therapeutic target and diagnostic marker.

Role of plasminogen activator inhibitor-1 in oral tongue squamous cell carcinoma: An immunohistochemical and in vitro analysis

ObjectiveTo evaluate the influence of plasminogen activator inhibitor-1 (PAI-1) on the biological behavior and prognosis of oral tongue squamous cell carcinoma (OTSCC). MethodsImmunoexpression of PAI-1 was analyzed in 60 OTSCC specimens and classified as low-expression (≤50% of positive cells) or high-expression (>50%). In vitro effects of recombinant human PAI-1 (rhPAI-1) were assessed through functional assays on the OTSCC-derived cell line SCC-25. Three cell groups were evaluated: G0 (control), G10 (10 nM rhPAI-1), and G20 (20 nM rhPAI-1). ResultsHigh membrane expression of PAI-1 was associated with tumor budding (p = 0.046) and high-risk cases (p = 0.043). Cytoplasmic and membrane expression of PAI-1 was not associated with patient survival. Cell viability (p = 0.020) and progression to the S-phase of the cell cycle (p = 0.024) were higher in G10 and G20 at 24 h. The percentages of apoptotic/necrotic cells were not affected by rhPAI-1. The presence of rhPAI-1 increased cell migration (p = 0.039) and invasion (p = 0.039) after 24 and 72 h, respectively. ConclusionOur findings indicate the involvement of PAI-1 in the biological behavior of OTSCC, although its expression may not predict patient survival. The in vitro results suggest that PAI-1 stimulates cell proliferation, migration and invasion and may contribute to the aggressive phenotype of OTSCC.

Abstract 11929: PAI-1 is Cardioprotective in Human Inflammatory Cardiomyopathy

Introduction: Preclinical data indicate that plasminogen activator inhibitor-1 (PAI-1) is cardioprotective by repressing fibrosis through TGF-β and plasminogen mediated pathways. Moreover, PAI-1 is suggested to be involved in the recruitment and polarization of M2 macrophages. Hypothesis: Elevated myocardial PAI-1 expression protects from fibrosis and acute inflammatory response. Methods: Endomyocardial biopsies (EMBs) of patients with dilated cardiomyopathy (DCM, n=27) and inflammatory dilated cardiomyopathy (DCMi, n=149) were retrospectively analyzed for PAI-1 expression, markers of fibrosis and M1/M2 macrophage polarization. Results: Patients with high-grade myocardial inflammation (DCMi-high, CD3 + lymphocytes > 30 cells/mm 2 ) had significantly increased PAI-1 levels compared to DCM and low-grade DCMi patients (DCMi-low, CD3 + lymphocytes = 14 - 30 cells/mm 2 ) (15.5 ± 0.4 % vs. 1.0 ± 0.1 % and 4.0 ± 0.1 %, p ≤ 0.001). Elevated PAI-1 expression in DCMi-high subjects was associated with a diminished degree of tissue fibrosis, accompanied by decreased levels of TGF-β and a reduced number of cardiac myofibroblasts. In addition, elevation of PAI-1 led to a shift from M1 to M2 macrophages. Conclusions: Our findings give evidence that increased expression of PAI-1 in DCMi patients suppresses cardiac fibrosis and promotes M2 macrophage polarization. Thus, PAI-1 could serve as a potential prognostic biomarker of cardiac fibrosis and inflammation, as well as possible therapeutic target in inflammatory cardiomyopathies.

The Plasma Level of IL-1β As a Biomarker of Angiopathy in Systemic Chronic Active EBV Infection

Background and aim: Systemic chronic active Epstein-Barr virus infection (sCAEBV) is an intractable rare disease revealing persistent systemic inflammation with clonal proliferation of EBV-infected T- or NK-cells. 25% of sCAEBV patients accompany angiopathy such as aneurysm and vasculitis. (Yonese et al. Blood advances. 2020). Because angiopathy degrades patients' quality of life and is one of the main causes of death in sCAEBV, it is crucial to clarify the mechanisms of angiopathy development in sCAEBV. Interleukin-1β (IL-1β) and tumor necrosis factor α (TNFα) are reported to be involved in angiopathy onset. We investigated if IL-1β and TNFα play roles to induce vascular endothelial cell damage in sCAEBV with angiopathy.Methods: sCAEBV patients were diagnosed when meeting all of the following four conditions: 1) inflammation persisting for more than 3 months, 2) increasing EBV-DNA in peripheral blood (PB) or in diseased tissue, 3) EBV infected T- or NK-cells, 4) not applying to other known diseases. We measured the plasma concentration of cytokines by high sensitivity cytokine beads assay (MILLIPLEX ®MAP Kit). We isolated EBV-infected cells and monocytes by magnetic beads (MACS ® Cell Separation). Ea.hy926, a human umbilical vein endothelial cell line, was used as a vascular endothelial cell model.Results: Samples from 17 sCAEBV patients (infected cell types: CD4 in 7; CD8 in 1; and CD56 in 9) and 8 healthy donors were examined. We detected elevated levels of IL-1β in 4 out of 17 sCAEBV patient's plasma. Interestingly, among the 4, 3 had clinically associated angiopathy: 1 aneurysm, 1 vasculitis, and 1 intracranial vascular lesions with multiple cerebral infarctions. The EBV-infected cells of these 3 patients were CD4-positive cells. The TNFα concentration of patients' plasma was higher than that of healthy donors, but there was no correlation with angiopathy. The mRNA of IL-1β in the EBV-infected cells of patients with high plasma IL-1β was not enhanced compared to that of patients with undetectable plasma IL-1β. In one patient with high plasma IL-1β, the level of IL-1β mRNA of the monocytes was 17.2 times higher than the level of the same patient's EBV-infected cells. IL-1β inhibited the proliferation of Ea.hy926 cells. IL-1β upregulated the mRNA expression of Tissue factor (TF) as well as Plasminogen activator inhibitor-1 (PAI-1) and suppressed the mRNA of Thrombomodulin (TM) in Ea.hy926 cells.Discussion: IL-1β originally exists in immunocompetent cells such as CD4-positive cells in the form of precursor protein (pro-IL-1β). In the occurrence of inflammation, pro-IL-1β is cleaved by caspase-1 activated by the inflammasome, and the production and the secretion of IL-1β is induced without mRNA elevation. The infected cells of sCAEBV patients with high level plasma IL-1β and vascular lesion were all CD4-positive. Consequently, we suspect that EBV-infected, CD4-positive cells are responsible for the production of IL-1β. Likewise, we detected high expression of IL-1β in monocytes derived from a patient with high plasma IL-1β. Based on these facts, we set two hypotheses on the production of IL-1β in sCAEBV. One is the production in EBV-infected cells by the cleavage of pro-IL-1β. The other is the production through transcription and translation in monocytes. IL-1β suppressed the proliferation of Ea.hy926 cells. In the same cells, IL-1β also induced TF and PAI-1 expression and suppressed TM expression. These results suggest that IL-1β may induce vascular damage and blood coagulation to cause angiopathy.Conclusion: In sCAEBV, IL-1β may be a biomarker of angiopathy. IL-1β may be a therapeutic target to treat sCAEBV accompanying vascular lesions. DisclosuresArai: Abbvie GK: Honoraria; BMS: Honoraria; Chugai Pharmaceutical Co Ltd: Honoraria, Research Funding; Eisai Co Ltd: Research Funding; Abbott Japan LLC: Honoraria; Kyowa Kirin Co ltd: Honoraria, Research Funding; Ono Pharmaceutical Co ltd: Honoraria, Research Funding; Nippon Shinyaku Co Ltd: Honoraria, Research Funding; Otsuka Pharmaceutical Co ltd: Research Funding; Novartis Pharma KK: Honoraria; Takeda Pharmaceuticals Co Ltd: Honoraria, Research Funding; Shionogi & Co ltd: Research Funding; Asahi Kasei Pharma Corporation: Research Funding; Sanofi KK: Honoraria; Pfizer Japan Inc: Honoraria; Astellas Pharma Inc: Honoraria.