Plasminogen activator inhibitor-1 (PAI-1): a key factor linking fibrinolysis and age-related subclinical and clinical conditions

In vitro characterization of sonothrombolysis and echocontrast agents to treat ischemic stroke

The development of adjuvant techniques to improve thrombolytic efficacy is important for advancing ischemic stroke therapy. We characterized octafluoropropane and recombinant tissue plasminogen activator (rt-PA)-loaded echogenic liposomes (OFP t-ELIP) using differential interference and fluorescence microscopy, attenuation spectroscopy, and electrozone sensing. The loading of rt-PA in OFP t-ELIP was assessed using spectrophotometry. Further, it was tested whether the agent shields rt-PA against degradation by plasminogen activator inhibitor-1 (PAI-1). An in vitro system was used to assess whether ultrasound (US) combined with either Definity or OFP t-ELIP enhances rt-PA thrombolysis. Human whole blood clots were mounted in a flow system and visualized using an inverted microscope. The perfusate consisted of either (1) plasma alone, (2) rt-PA, (3) OFP t-ELIP, (4) rt-PA and US, (5) OFP t-ELIP and US, (6) Definity and US, or (7) rt-PA, Definity, and US (n = 16 clots per group). An intermittent US insonation scheme was employed (220 kHz frequency, and 0.44 MPa peak-to-peak pressures) for 30 min. Microscopic imaging revealed that OFP t-ELIP included a variety of structures such as liposomes (with and without gas) and lipid-shelled microbubbles. OFP t-ELIP preserved up to 76% of rt-PA activity in the presence of PAI-1, whereas only 24% activity was preserved for unencapsulated rt-PA. The use of US with rt-PA and Definity enhanced lytic efficacy (p < 0.05) relative to rt-PA alone. US combined with OFP t-ELIP enhanced lysis over OFP t-ELIP alone (p < 0.01). These results demonstrate that ultrasound combined with Definity or OFP t-ELIP can enhance the lytic activity relative to rt-PA or OFP t-ELIP alone, respectively.

Muscle wasting: A review of exercise, classical and non-classical RAS axes

This review identifies how the classical/non‐classical renin‐angiotensin system (RAS) and exercise influence muscle wasting. The classical RAS axis enhances muscle loss through the interaction with NADPH oxidase (NOX), ubiquitin proteasome system (UPS), protein synthesis and fibrosis pathways. The mainstream hypothesis identifies reactive oxygen species (ROS) as the key pathway in muscle, this review recognizes alternative pathways that lead to an increase in muscle wasting through the classical RAS axis. In addition, pathways in which the non‐classical RAS axis and exercise inhibit the classical RAS axis are also explored. The non‐classical RAS axis and exercise have a significant negative impact on ROS production and protein synthesis. The non‐classical RAS axis has been identified in this review to directly affect protein synthesis pathways not by altering the pre‐existing intracellular ROS level, further supporting the idea that muscle wasting caused by the classical RAS system is not entirely due to ROS production. Exercise has been identified to modify the RAS axes making it a therapeutic option.

Haplotype analysis of SERPINE1 gene: Risk for aneurysmal subarachnoid hemorrhage and clinical outcomes

Background

Aneurysmal subarachnoid hemorrhage (aSAH) has high fatality and permanent disability rates due to the severe damage to brain cells and inflammation. The SERPINE1 gene that encodes PAI‐1 for the regulation of tissue plasminogen activator is considered an important therapeutic target for aSAH.

Methods

Six SNPs in the SERPINE1 gene (in order of rs2227631, rs1799889, rs6092, rs6090, rs2227684, rs7242) were investigated. Blood samples were genotyped with Taqman genotyping assays and pyrosequencing. The experiment‐wide statistically significant threshold for single marker analysis was set at p < 0.01 after evaluation of independent markers. Haplotype analysis was performed in Haplo.stats package with permutation tests. Bonferroni correction for multiple comparison in dominant, additive, and recessive model was applied.

Results

A total of 146 aSAH patients and 49 control subjects were involved in this study. The rs2227631 G allele is significant (p = 0.01) for aSAH compared to control. In aSAH group, haplotype analysis showed that G5GGGT homozygotes in recessive model were associated with delayed cerebral ischemia (p < 0.01, Odds Ratio = 5.14, 95% CI = 1.45–18.18), clinical vasospasm (p = 0.01, Odds Ratio = 4.58, 95% CI = 1.30–16.13), and longer intensive care unit stay (p = 0.01). By contrast, the G5GGAG carriers were associated with less incidence of cerebral edema (p < 0.01) and higher Glasgow Coma Scale (p < 0.01). The A4GGGT carriers were associated with less incidence of severe hypertension (>140/90) (p < 0.01).

Conclusion

The results suggested an important regulatory role of the SERPINE1 gene polymorphism in clinical outcomes of aSAH.

Circadian Rhythm of Cardiovascular Disease: The Potential of Chronotherapy With Aspirin

Almost all the systems in our body adhere to a daily 24 h rhythm. The cardiovascular system is also affected by this 24 h rhythm. In the morning there is a change in various cardiovascular processes, including platelet aggregability. These changes may play a role in the relative excess of early morning cardiovascular events. The number of recurrent cardiovascular diseases (CVD) could, in theory, be reduced by responding to this 24 h rhythm with timed medication intake (chronotherapy), which also applies to aspirin. Multiple studies on chronotherapy with low-dose aspirin are promising, showing a decrease in early morning platelet activity with evening intake compared with morning intake. However, in order to further demonstrate its clinical impact, randomized trials with cardiovascular events as a primary outcome are needed. This review discusses the available evidence of the effects of circadian rhythm on CVD and the potential positive effect of chronotherapy with aspirin.

Long intergenic non-coding RNAs regulate human lung fibroblast function: Implications for idiopathic pulmonary fibrosis

Phenotypic changes in lung fibroblasts are believed to contribute to the development of Idiopathic Pulmonary Fibrosis (IPF), a progressive and fatal lung disease. Long intergenic non-coding RNAs (lincRNAs) have been identified as novel regulators of gene expression and protein activity. In non-stimulated cells, we observed reduced proliferation and inflammation but no difference in the fibrotic response of IPF fibroblasts. These functional changes in non-stimulated cells were associated with changes in the expression of the histone marks, H3K4me1, H3K4me3 and H3K27ac indicating a possible involvement of epigenetics. Following activation with TGF-β1 and IL-1β, we demonstrated an increased fibrotic but reduced inflammatory response in IPF fibroblasts. There was no significant difference in proliferation following PDGF exposure. The lincRNAs, LINC00960 and LINC01140 were upregulated in IPF fibroblasts. Knockdown studies showed that LINC00960 and LINC01140 were positive regulators of proliferation in both control and IPF fibroblasts but had no effect upon the fibrotic response. Knockdown of LINC01140 but not LINC00960 increased the inflammatory response, which was greater in IPF compared to control fibroblasts. Overall, these studies demonstrate for the first time that lincRNAs are important regulators of proliferation and inflammation in human lung fibroblasts and that these might mediate the reduced inflammatory response observed in IPF-derived fibroblasts.

Gum Arabic Ameliorates Impaired Coagulation and Cardiotoxicity Induced by Water-Pipe Smoke Exposure in Mice

Water-pipe smoking (WPS) is prevalent in the East and elsewhere. WPS exposure is known to induce thrombosis and cardiovascular toxicity involving inflammation and oxidative stress. Here, we have investigated the effect of Gum Arabic (GA), a prebiotic with anti-oxidant, anti-inflammatory and cytoprotective properties, on WPS exposure (30 min/day for 1 month) on coagulation and cardiac homeostasis, and their possible underlying mechanisms in mice. Animals received either GA in drinking water (15%, w/v) or water only for the entire duration of study. GA significantly mitigated thrombosis in pial microvessels in vivo, platelet aggregation in vitro, and the shortening of prothrombin time induced by WPS exposure. The increase in plasma concentrations of fibrinogen, plasminogen activator inhibitor-1 and markers of lipid peroxidation, 8-isoprostane and malondialdehyde, induced by WPS were significantly reduced by GA administration. Moreover, WPS exposure induced a significant increase in systolic blood pressure and the concentrations of the pro-inflammatory cytokines tumor necrosis factor-α and interleukin 1β in heart homogenates. GA significantly alleviated these effects, and prevented the decrease of reduced glutathione, catalase and total nitric oxide levels in heart homogenates. Immunohistochemical analysis of the hearts showed that WPS exposure increased nuclear factor erythroid-derived 2-like 2 (Nrf2) expressions by cardiac myocytes and endothelial cells, and these effects were potentiated by the combination of GA and WPS. WPS also increased DNA damage and cleaved caspase 3, and GA administration prevented these effects. Our data, obtained in experimental murine model of WPS exposure, show that GA ameliorates WPS-induced coagulation and cardiovascular inflammation, oxidative stress, DNA damage and apoptosis, through a mechanism involving Nrf2 activation.

Non-traditional biomarkers and incident diabetes in the Diabetes Prevention Program: comparative effects of lifestyle and metformin interventions

AIMS/HYPOTHESIS

We compared the associations of circulating biomarkers of inflammation, endothelial and adipocyte dysfunction and coagulation with incident diabetes in the placebo, lifestyle and metformin intervention arms of the Diabetes Prevention Program, a randomised clinical trial, to determine whether reported associations in general populations are reproduced in individuals with impaired glucose tolerance, and whether these associations are independent of traditional diabetes risk factors. We further investigated whether biomarker-incident diabetes associations are influenced by interventions that alter pathophysiology, biomarker concentrations and rates of incident diabetes.

METHODS

The Diabetes Prevention Program randomised 3234 individuals with impaired glucose tolerance into placebo, metformin (850 mg twice daily) and intensive lifestyle groups and showed that metformin and lifestyle reduced incident diabetes by 31% and 58%, respectively compared with placebo over an average follow-up period of 3.2 years. For this study, we measured adiponectin, leptin, tissue plasminogen activator (as a surrogate for plasminogen activator inhibitor 1), high-sensitivity C-reactive protein, IL-6, monocyte chemotactic protein 1, fibrinogen, E-selectin and intercellular adhesion molecule 1 at baseline and at 1 year by specific immunoassays. Traditional diabetes risk factors were defined as family history, HDL-cholesterol, triacylglycerol, BMI, fasting and 2 h glucose, HbA_1c, systolic blood pressure, inverse of fasting insulin and insulinogenic index. Cox proportional hazard models were used to assess the effects of each biomarker on the development of diabetes assessed semi-annually and the effects of covariates on these.

RESULTS

E-selectin, (HR 1.19 [95% CI 1.06, 1.34]), adiponectin (0.84 [0.71, 0.99]) and tissue plasminogen activator (1.13 [1.03, 1.24]) were associated with incident diabetes in the placebo group, independent of diabetes risk factors. Only the association between adiponectin and diabetes was maintained in the lifestyle (0.69 [0.52, 0.92]) and metformin groups (0.79 [0.66, 0.94]). E-selectin was not related to diabetes development in either lifestyle or metformin groups. A novel association appeared for change in IL-6 in the metformin group (1.09 [1.021, 1.173]) and for baseline leptin in the lifestyle groups (1.31 [1.06, 1.63]).

CONCLUSIONS/INTERPRETATION

These findings clarify associations between an extensive group of biomarkers and incident diabetes in a multi-ethnic cohort with impaired glucose tolerance, the effects of diabetes risk factors on these, and demonstrate differential modification of associations by interventions. They strengthen evidence linking adiponectin to diabetes development, and argue against a central role for endothelial dysfunction. The findings have implications for the pathophysiology of diabetes development and its prevention.

Inflammation, depression and cardiovascular disease in women: the role of the immune system across critical reproductive events

Women are at increased risk for developing depression and cardiovascular disease (CVD) across the lifespan and their comorbidity is associated with adverse outcomes that contribute significantly to rates of morbidity and mortality in women worldwide. Immune-system activity has been implicated in the etiology of both depression and CVD, but it is unclear how inflammation contributes to sex differences in this comorbidity. This narrative review provides an updated synthesis of research examining the association of inflammation with depression and CVD, and their comorbidity in women. Recent research provides evidence of pro-inflammatory states and sex differences associated with alterations in the hypothalamic-pituitary-adrenal axis, the renin-angiotensin-aldosterone system and the serotonin/kynurenine pathway, that likely contribute to the development of depression and CVD. Changes to inflammatory cytokines in relation to reproductive periods of hormonal fluctuation (i.e. the menstrual cycle, perinatal period and menopause) are highlighted and provide a greater understanding of the unique vulnerability women experience in developing both depressed mood and adverse cardiovascular events. Inflammatory biomarkers hold substantial promise when combined with a patient's reproductive and mental health history to aid in the prediction, identification and treatment of the women most at risk for CVD and depression. However, more research is needed to improve our understanding of the mechanisms underlying inflammation in relation to their comorbidity, and how these findings can be translated to improve women's health.

Plasminogen Activator Inhibitor-1 4G/5G Polymorphism Contributes to Osteonecrosis of the Femoral Head Susceptibility: Evidence from a Systematic Review and Meta-analysis

BACKGROUND

The Plasminogen Activator Inhibitor-1 gene 4G/5G (PAI-1 4G/5G) polymorphism has been suggested to be associated with osteonecrosis of the femoral head (ONFH) susceptibility; however, the results are conflicting and inconclusive. We have carried out a comprehensive meta-analysis to derive a more precise estimation of the association.

METHODS

A comprehensive search in PubMed, EMBASE, Google Scholar, and ISI Web of Knowledge databases was conducted to identify all eligible case-control publications investigating the association between PAI-1 4G/5G polymorphism and ONFH risk. Odds ratios (OR) and corresponding 95% confidence intervals (CI) were used to assess the association.

RESULTS

A total of six studies with 456 cases and 1,019 controls were included in this review. Three studies were from Caucasian descendants and the three others were from East Asian descendants. Overall analysis suggests a significant association between PAI-1 4G/5G polymorphism and ONFH risk under the allele model (4G vs. 5G: OR =1.540, 95% CI =1.055-2.248, P=0.025) and the recessive model (4G4G vs. 4G5G+5G5G: OR=1.931, 95% CI: 1.162-3.207, P=0.011). When stratified by ethnicity, we have found a significant association between PAI-1 4G/5G polymorphism and ONFH risk among the Caucasian (4G5G vs. 5G5G: OR=1.806, 95% CI: 1.064-3.067, P=0.029) and East Asians (4G4G vs. 5G5G: OR=1.619, 95% CI: 1.025-2.556, P=0.039 and 4G4G vs. 4G5G+5G5G: OR=1.665, 95% CI: 1.207-2.297, P=0.002).

CONCLUSION

The present meta-analysis suggested that PAI-1 4G/5G (rs1799889) polymorphism is a potential risk factor for development of ONFH. However, large-scale and well-designed case-control studies in different ethnicities are required to validate these results.

The Role of Adipokines in Surgical Procedures Requiring Both Liver Regeneration and Vascular Occlusion

Liver regeneration is a perfectly calibrated mechanism crucial to increase mass recovery of small size grafts from living donor liver transplantation, as well as in other surgical procedures including hepatic resections and liver transplantation from cadaveric donors. Regeneration involves multiple events and pathways in which several adipokines contribute to their orchestration and drive hepatocytes to proliferate. In addition, ischemia-reperfusion injury is a critical factor in hepatic resection and liver transplantation associated with liver failure or graft dysfunction post-surgery. This review aims to summarize the existing knowledge in the role of adipokines in surgical procedures requiring both liver regeneration and vascular occlusion, which increases ischemia-reperfusion injury and regenerative failure. We expose and discuss results in small-for-size liver transplantation and hepatic resections from animal studies focused on the modulation of the main adipokines associated with liver diseases and/or regeneration published in the last five years and analyze future perspectives and their applicability as potential targets to decrease ischemia-reperfusion injury and improve regeneration highlighting marginal states such as steatosis. In our view, adipokines means a promising approach to translate to the bedside to improve the recovery of patients subjected to partial hepatectomy and to increase the availability of organs for transplantation.

DNA methylation age is associated with an altered hemostatic profile in a multiethnic meta-analysis

Many hemostatic factors are associated with age and age-related diseases; however, much remains unknown about the biological mechanisms linking aging and hemostatic factors. DNA methylation is a novel means by which to assess epigenetic aging, which is a measure of age and the aging processes as determined by altered epigenetic states. We used a meta-analysis approach to examine the association between measures of epigenetic aging and hemostatic factors, as well as a clotting time measure. For fibrinogen, we performed European and African ancestry-specific meta-analyses which were then combined via a random effects meta-analysis. For all other measures we could not estimate ancestry-specific effects and used a single fixed effects meta-analysis. We found that 1-year higher extrinsic epigenetic age as compared with chronological age was associated with higher fibrinogen (0.004 g/L/y; 95% confidence interval, 0.001-0.007; P = .01) and plasminogen activator inhibitor 1 (PAI-1; 0.13 U/mL/y; 95% confidence interval, 0.07-0.20; P = 6.6 × 10-5) concentrations, as well as lower activated partial thromboplastin time, a measure of clotting time. We replicated PAI-1 associations using an independent cohort. To further elucidate potential functional mechanisms, we associated epigenetic aging with expression levels of the PAI-1 protein encoding gene (SERPINE1) and the 3 fibrinogen subunit-encoding genes (FGA, FGG, and FGB) in both peripheral blood and aorta intima-media samples. We observed associations between accelerated epigenetic aging and transcription of FGG in both tissues. Collectively, our results indicate that accelerated epigenetic aging is associated with a procoagulation hemostatic profile, and that epigenetic aging may regulate hemostasis in part via gene transcription.

Akkermansia muciniphila can reduce the damage of gluco/lipotoxicity, oxidative stress and inflammation, and normalize intestine microbiota in streptozotocin-induced diabetic rats

This study aimed to investigate how Akkermansia muciniphila can implicate type 2 diabetes mellitus and the mechanisms underlying the effects A. muciniphila on type 2 diabetes mellitus. Normal and streptozotocin-induced diabetic Sprague-Dawley rats were orally administered with A. muciniphila and solvent. After 4 weeks of treatment, diabetic rats orally administered with live or pasteurized A. muciniphila exhibited significant increase in the blood concentration of high-density lipoprotein, and decrease in the hepatic glycogen, serum plasminogen activator inhibitor-1, tumor necrosis factor-α, lipopolysaccharide, malondialdehyde and total glucagon-like peptide-1. Moreover, diabetic rats orally administered with A. muciniphila showed significantly increased species alpha diversity and gene function in gut microbes. These results indicated that A. muciniphila can improve liver function, reduce gluco/lipotoxicity, alleviate oxidative stress, suppress inflammation and normalize intestine microbiota of the host animal, thereby ameliorating type 2 diabetes mellitus. Akkermansia muciniphila might be considered as one of the ideal new probiotics used in the management of type 2 diabetes mellitus in future.

Upregulation of Plasminogen Activator Inhibitor-1 in Irradiated Recipient Arteries and Veins from Free Tissue Transfer Reconstruction in Cancer Patients

Background

Clinical studies have shown that radiotherapy can induce vascular disease at the site of exposure but is usually not clinically evident until years after treatment. We have studied irradiated human arteries and veins to better understand the underlying biology in search of future treatments. The aim was to investigate whether radiotherapy contributed to a sustained expression of plasminogen activator inhibitor-1 (PAI-1) in human arteries and veins.

Methods

Irradiated arteries and veins were harvested, together with unirradiated control vessels, from patients undergoing free tissue transfer reconstruction at a median time of 90 weeks [5–650] following radiation exposure. Differential gene expression of PAI-1 was analysed, together with immunohistochemistry (IHC) and immunofluorescence (IF).

Results

PAI-1 gene expression was increased in both arteries (p = 0.012) and veins (p < 0.001) in irradiated compared to unirradiated control vessels. IHC and IF indicated that cells expressing PAI-1 were located in the adventitia of both arteries and veins and colocalized with cells positive for CD68, CD45, and α-SMA in arteries and with CD45 and α-SMA in veins.

Conclusion

The current study shows a sustained upregulation of PAI-1 in both arteries and veins after exposure to ionizing radiation, indicating a chronic inflammation mainly in the adventitia. We believe that the results contribute to further understanding of radiation-induced vascular disease, where targeting PAI-1 may be a potential treatment.

Changes in spontaneous thrombolytic activity during progression of atherosclerosis in Apo-/- and LDLR-/- double knockout mice

BACKGROUND

Atherosclerosis is characterized by a hypercoagulable state, during which both coagulation and thrombolytic factors are activated simultaneously. However, details regarding the thrombolytic pathway in this context remain unknown. Here we investigated the changes in spontaneous thrombolytic activity during atherosclerotic progression in Apo-/-LDLR-/- double-knockout mice (DKO group).

METHODS

We fed DKO mice and their controls (C57Bl6 mice) a high-fat diet for a total of 22 weeks and evaluated them at 14 and 22 weeks. The amount of atherosclerosis was estimated as the ratio of the atherosclerotic to total aortic intimal area. In addition, we used immunohistochemistry to analyze the expression of PAI-1, t-PA, and eNOS in atherosclerotic regions. To evaluate thrombolysis, we used a He-Ne laser to induce thrombosis in vessels of the cremaster muscle and then measured the thrombus volume over time.

RESULTS

The atherosclerotic area was increased and thrombolytic activity was decreased in DKO group compared with the control group. Furthermore, the plasma PAI-1 level was 3 times greater in the DKO group than in the control group. In support of these results, immunohistochemistry showed increased PAI-1 expression in the DKO group, whereas t-PA and eNOS expression was greater in the control group.

CONCLUSION

Progression of atherosclerosis led to a reduction in thrombolytic activity through decreases in t-PA and eNOS levels and an increase in PAI-1 production. These findings indicate that decreases in factors that promote spontaneous thrombolytic activity may indicate increased risk for the progression of atherosclerosis.

Western diet given to healthy rats mimics the human phenotype of diabetic cardiomyopathy

Diabetes mellitus (DM) is a major problem worldwide. Within this patient group, cardiovascular diseases are the biggest cause of morbidity and mortality. Diabetic cardiomyopathy (DCM) is defined as diabetes-associated structural and functional changes in the myocardium, not directly attributable to other confounding factors such as coronary artery disease or hypertension. Pathophysiology of DCM remains unclear due to a lack of adequate animal models reflecting the current pandemic of diabetes, associated with a high increased sugar intake and the 'Western' lifestyle. The aim of this study was to develop an animal model mimicking this 'Western' lifestyle causing a human-like phenotype of DCM. Twenty-four Sprague-Dawley rats were randomly assigned into a normal or a 'Western' diet group for 18 weeks. Glucose and insulin levels were measured with an OGTT. Heart function was assessed by echocardiography and hemodynamic measurements in vivo. Cardiac fibrosis and inflammation were investigated in vitro. 'Western' diet given to healthy rats for 18 weeks induced hyperglycemia together with increased AGEs levels, insulin levels and hypertriglyceridemia. Heart function was altered with increased end-diastolic pressure, left ventricle hypertrophy. Changes in vivo were associated with increased collagen deposition and increased PAI-1 levels in the heart. High-sugar diet or 'Western' diet causes T2DM and the hallmarks of DCM in rats, reflecting the phenotype of the disease seen in patients. Using this new model of T2DM with DCM might open new insight in understanding the pathophysiology of DCM and on a long term, test targeted therapies for T2DM with DCM patients.

High ApoD protein level in the round ligament fat depot of severely obese women is associated with an improved inflammatory profile

PURPOSE

Apolipoprotein D (ApoD) is a lipocalin participating in lipid transport. It binds to a variety of ligands, with a higher affinity for arachidonic acid, and is thought to have a diverse array of functions. We investigated a potential role for ApoD in insulin sensitivity, inflammation, and thrombosis-processes related to lipid metabolism-in severely obese women.

METHODS

We measured ApoD expression in a cohort of 44 severely obese women including dysmetabolic and non-dysmetabolic patients. Physical and metabolic characteristics of these women were determined from anthropometric measurements and blood samples. ApoD was quantified at the mRNA and protein levels in samples from three intra-abdominal adipose tissues (AT): omental, mesenteric and round ligament (RL).

RESULTS

ApoD protein levels were highly variable between AT of the same individual. High ApoD protein levels, particularly in the RL depot, were linked to lower plasma insulin levels (-40%, p = 0.015) and insulin resistance (-47%, p = 0.022), and increased insulin sensitivity (+10%, p = 0.008). Lower circulating pro-inflammatory PAI-1 (-39%, p = 0.001), and TNF-α (-19%, p = 0.030) levels were also correlated to high ApoD protein in the RL AT.

CONCLUSIONS

ApoD variability between AT was consistent with different accumulation efficiencies and/or metabolic functions according to the anatomic location of fat depots. Most statistically significant correlations implicated ApoD protein levels, in agreement with protein accumulation in target tissues. These correlations associated higher ApoD levels in fat depots with improved metabolic health in severely obese women.

The Impact of Insulin Resistance and Chronic Kidney Disease on Inflammation and Cardiovascular Disease

There is extensive evidence showing that insulin resistance (IR) is associated with chronic low-grade inflammation. Furthermore, IR has been shown to increase the risk for cardiovascular disease (CVD), even in nondiabetic patients, and is currently considered as a “nontraditional” risk factor contributing to CVD by promoting hypertension, oxidative stress, endothelial dysfunction, dyslipidemia, and type 2 diabetes mellitus. However, chronic kidney disease (CKD) is also considered a state of low-grade inflammation. In addition, CKD is considered an IR state and has been described as an independent risk factor for the development of CVD, as even early-stage CKD is associated with an estimated 40% to 100% increase in CVD risk. There is also strong evidence indicating that inflammation per se plays a crucial role in both the initiation and progression of CVD. Given the above, the combined effect of IR and CKD may significantly increase the risk of inflammation and CVD. This review aims to focus on the complex interplay between IR, CKD, inflammation, and CVD and will present and discuss the current clinical and scientific data pertaining to the impact of IR and CKD on inflammation and CVD.

In vitro and ex vivo anti-fibrotic effects of LY2109761, a small molecule inhibitor against TGF-β

Fibrosis is a pathophysiological state characterized by the excessive formation/deposition of fibrous extracellular matrix. Transforming growth factor-beta (TGF-β) is a central profibrotic mediator, and targeting TGF-β is a promising strategy in the development of drugs for the treatment of fibrosis. Therefore, the effect of LY2109761, a small molecule inhibitor against TGF-β with targets beyond TGF-β signaling, on fibrogenesis was elucidated in vitro (HepG2 cells and LX-2 cells) and ex vivo (human and rat precision-cut liver slices). Our results displayed an anti-fibrotic effect of LY2109761, as it markedly down-regulated gene and protein expression of collagen type 1, as well as gene expression of the inhibitor of metalloproteinases 1. This effect on fibrosis markers was partially mediated by targeting TGF-β signaling, seeing that LY2109761 inhibited TGF-β1 gene expression and SMAD2 protein phosphorylation. Interestingly, particularly at a high concentration, LY2109761 decreased SMAD1 protein phosphorylation and gene expression of the inhibitor of DNA binding 1, which appeared to be TGF-β-independent effects. In conclusion, LY2109761 exhibited preclinical anti-fibrotic effects via both TGF-β-dependent and -independent pathways. These results illustrate that small molecule inhibitors directed against TGF-β could possibly influence numerous signaling pathways and thereby mitigate fibrogenesis.

Correlation between PAI-1, leptin and ferritin with HOMA in HIV/AIDS patients

BACKGROUND

Data about correlation of interleukins (IL-1 α, IL-1 β, IFN γ, IL-2, IL-4, IL-6, IL-8, IL-10), adipocytokines (leptin, adiponectin, monocyte chemoattractant protein-1 (MCP-1), resistin, plasminogen activator inhibitor-1 (PAI-1), tumor necrosis factor alpha (TNFα), ferritin, C reactive protein (CRP) and vascular endothelial growth factor (VEGF) with homeostasis model assessment (HOMA) in HIV/AIDS patients are still limited. Therefore the aim of this study was to evaluate the possible correlations of serum levels of PAI-1, leptin and ferritin with HOMA in HIV/AIDS patients treated with combined antiretroviral therapy (cART).

METHODS

This cross-sectional study included 64 HIV/AIDS patients, all Caucasians, receiving cART at the HIV/AIDS Centre, Belgrade, Serbia. PAI-1, leptin, ferritin and insulin levels were measured using the Metabolic Syndrome Array I (Randox Laboratories Ltd., London, UK), while adiponectin and resistin levels were measured using Metabolic Syndrome Array II (Randox Laboratories Ltd., London, UK), interleukins (IL-1 α, IL-1 β, IFN γ, IL-2, IL-4, IL-6, IL-8, IL-10), MCP-1, TNF-α as well as VEGF was measured using Cytokine Array I (Randox Laboratories Ltd., London, UK). Insulin resistance was determined using the homeostasis model assessment index (HOMA). Multicollinearity of independent variables in multivariate model was analyzed using Variance Inflation Factor.

RESULTS

Correlation analysis revealed significant correlations between HOMA and waist circumference, body mass index, patients' age, number of cART combinations and triglycerides (p = 0.001, p = 0.001, p = 0.050, p = 0.044, p = 0.002, respectively). HOMA negatively correlated with levels of high density lipoprotein (HDL) (Rho = -0.282; p = 0.025). PAI-1 (Rho = 0.334; p= 0.007) and leptin (Rho = 0.492; p = 0.001) together with ferritin (Rho = 0.396, p = 0.001) positively and significantly correlated with HOMA. Levels of IL-1 α, IL-1 β, IFN γ, IL-2, IL-4, IL-6, IL-8, IL-10, adiponectin, MCP-1, resistin, TNF-α, CRP and VEGF did not significantly correlate with HOMA. Further, multiple logistic regression showed that there is a statistically significant correlation between PAI, leptin and ferritin with HOMA levels (p = 0.042; p < 0.001, p = 0.009).

CONCLUSIONS

We showed significant correlation between PAI-1, leptin and ferritin, independently of each other with HOMA, in HIV/AIDS patients on cART.

The roles of PAI-1 gene polymorphisms in atherosclerotic diseases: A systematic review and meta-analysis involving 149,908 subjects

BACKGROUND

The roles of plasminogen activator inhibitor-1 (PAI-1) gene polymorphisms in atherosclerotic diseases were intensively analyzed, but the results of these studies were inconsistent. Therefore, we performed this study to better assess the relationship between PAI-1 genetic variations and atherosclerosis.

METHODS

Eligible studies were searched in PubMed, Medline, Embase and Web of Science. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess relationship between PAI-1 polymorphisms and atherosclerotic diseases.

RESULTS

Ninety-nine studies involving 62,739 cases and 87,169 controls were finally included. Significant associations with the risk of atherosclerosis were detected for the rs2227631 polymorphism in the dominant model (95% CI 0.84-1.00), for the rs1799889 polymorphism in the dominant (95% CI 1.01-1.18), recessive (95% CI 0.90-0.98) and allele (95% CI 1.01-1.12) models. Further subgroup analyses based on type of disease and ethnicity of participants suggested that the rs2227631 polymorphism was significantly associated with the risk of coronary artery disease in the dominant (95% CI 0.71-0.94) and allele (95% CI 0.80-0.94) models, whereas the rs1799889 polymorphism was significantly associated with the risk of myocardial infarction (dominant model: 95% CI 1.09-1.57; recessive model: 95% CI 0.71-0.96; allele model: 95% CI 1.05-1.28) and cerebral infarction (dominant model: 95% CI 1.68-3.51; additive model: 95% CI 0.39-0.77; allele model: 95% CI 1.23-2.00). Moreover, the rs1799889 polymorphism was also significantly correlated with the risk of atherosclerosis in both Asians (dominant model: 95% CI 1.10-1.83; allele model: 95% CI 1.03-1.41) and Caucasians (recessive model: 95% CI 0.87-0.97; allele model: 95% CI 1.01-1.12).

CONCLUSION

In conclusion, our findings indicate that PAI-1 rs2227631 and rs1799889 polymorphisms may serve as genetic biomarkers of atherosclerotic diseases.

A randomized, controlled, crossover pilot study of losartan for pediatric nonalcoholic fatty liver disease

Background

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in children, and currently, there are no FDA-approved therapies. Plasminogen activator inhibitor-1 (PAI-1) is elevated in children with NAFLD and associated with increased disease severity. Losartan potassium (losartan) is an angiotensin II receptor blocker (ARB) that reduces PAI-1 production and improves insulin sensitivity that has been proposed as a treatment for pediatric NAFLD but has not previously been tested.

Methods

This was an 8-week randomized, double-blind, placebo-controlled, phase 2a, crossover study (with a 6-week washout between conditions) for safety and preliminary efficacy of losartan 50 mg a day taken orally in 12 normotensive children with biopsy proven nonalcoholic steatohepatitis (NASH).

Results

Twelve children enrolled in the study, and nine completed all visits. No changes in blood pressure or serious adverse events occurred during the study. Trends in improvement in alanine aminotransferase (ALT), aspartate aminotransferase (AST), and homeostatic model assessment insulin resistance (HOMA-IR) were seen with losartan treatment compared to the placebo time-period. More participants decreased ALT on losartan as compared to placebo (89% [8 out 9] vs. 56% [5 out of 9], respectively).

Conclusions

This data provides preliminary evidence that losartan treatment is safe over 8 weeks in children with NAFLD and supports consideration of larger studies to test its efficacy.

Trial registration

URL and trial identification number: https://clinicaltrials.gov/show/NCT01913470, NCT01913470.

Date registered: August 1, 2013.

Role of plasminogen activator inhibitor-1 gene polymorphisms in osteoporosis: A study in Chinese post-menopausal women

Osteoporosis is a chronic multifactorial disease characterized by deterioration of bone mass and is vulnerable to bone fracture. Plasminogen activator inhibitor-1 (PAI-1) is an important molecule for maintenance of optimum bone mass. Several single-nucleotide polymorphisms (SNPs) in PAI-1 have been reported to alter PAI-1 expression and/or the translational level. In this report, we explored the possible role of common PAI-1 gene polymorphisms on predisposition to osteoporosis in a Chinese cohort. A total of 364 post-menopausal Chinese women diagnosed of having osteoporosis and 350 healthy females hailing from similar areas were enrolled in this study. Five common SNPs (−844G > A, −6754G/5G, +43G > A, +9785G > A and +11053T > G) were genotyped by polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP). Relative expression of PAI-1 mRNA and plasma PAI-1 levels were quantified by reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Prevalence of homozygous mutant (5G/5G) and minor allele (5G) of PAI-1 (−675 4G/5G) polymorphism was significantly more frequent in patients than in healthy controls (5G/5G: P < 0.0001, odds ratio (OR) = 3.18; 5G: P < 0.0001, OR = 1.65). Both plasma PAI-1 and relative mRNA expression levels were significantly lower in patients compared to healthy controls. Interestingly, the quantity of plasma PAI-1 and mRNA expression was correlated with PAI-1 (−675 4G/5G) polymorphism: subjects with 4G/4G genotype had elevated PAI-1 in comparison to homozygous mutant, and displayed lower quantity of PAI-1 protein and mRNA values. PAI-1 (−675 4G/5G) mutant is associated with susceptibility to development of osteoporosis in post-menopausal Chinese women. Furthermore, this variant in the promoter region alters plasma protein levels and relative expression of PAI-1.

A new assay for global fibrinolysis capacity (GFC): Investigating a critical system regulating hemostasis and thrombosis and other extravascular functions

For many years, the importance of fibrinolysis has been recognized, first for its intravascular antithrombotic action, and more recently for its many extravascular activities, associated with matrix degradation and tissue remodeling. In the blood circulation system, fibrinolysis prevents thrombosis, and is associated with various biological and clinical situations: risk factors for cardio-vascular diseases in high risk clinical situations (type II diabetes, hypertension, triglycerides, high BMI, elevated glucose, etc.), probably resulting from a significant reduction of the fibrinolysis potential, and elevation of PAI-1. Noteworthy, t-PA is mainly present as an inactive complex with PAI-1, and its concentration in plasma tends to follow that of PAI-1, but in a lesser extent. Hypofibrinolysis can favor the occurrence of thrombotic events, and possibly other biological dysfunctions. Fibrinolysis activity is however difficult to evaluate as it has a delayed activity after clot formation, is initiated and regulated after fibrin generation, and conversely to clotting, its action is delayed (long lag phase) and slow, before being dramatically amplified leading to rapid clot dissolution. We have designed a new assay for evaluating the global fibrinolytic capacity (GFC) in the body. Reagents are used in association with a specific instrument, which can be connected to any computer, and dedicated software is used for analyzing clot lysis kinetics. The assay is performed in a micro-cuvette, introduced into one of the instrument wells at 37 °C, and light transmittance is continuously measured. Assayed plasma is first supplemented with a limited and constant amount of t-PA with silica and is then clotted with thrombin and calcium. Clot dissolution (measurement of turbidity change) is recorded over time using the dedicated instrument (Lysis Timer), and clot lysis kinetics are analyzed with the associated software: primary and secondary derivatives of the light transmission curve give information on kinetics and completion of clot dissolution. Total assay time is about 1 h (but in the presence of hypofibrinolysis it can be prolonged). The concentration of t-PA used for the assay has been adjusted (100 ng/ml) to obtain an optimal sensitivity to hypofibrinolysis within a short time interval, and clot dissolution occurs within about 45 min for normal individuals, with a broad range from 30 min to 60 min, with some samples presenting a clot dissolution time >60 min (hypofibrinolysis). This new assay is performed with the tested plasma intrinsic factors, especially its own fibrinogen, and only exogeneous t-PA is added. GFC is highly sensitive to PAI-1 activity, but other factors regulating fibrinolysis contribute to the clot dissolution kinetics. Freshly prepared or frozen and thawed citrated plasma can be used. The usefulness of this assay for clinical applications is under investigation. Although fibrinolysis is mainly initiated in the body upon stimulation or blood clotting, and rapidly diluted and inhibited in the circulation, evaluation of its "residual" activity in plasma is expected to reflect its global body potential.

Histone deacetylase 2 (HDAC2) attenuates lipopolysaccharide (LPS)-induced inflammation by regulating PAI-1 expression

Background

Sepsis is a life-threatening organ dysfunction caused by dysregulated host response to infection, and is primarily characterized by an uncontrolled systemic inflammatory response. In the present study, we developed an effective adjunct therapy mediated by a novel mechanism, to attenuate overt inflammation. LPS-treated macrophages were adopted as an in vitro model of endotoxin-induced inflammation during sepsis. Experiments were carried out using primary mouse peritoneal macrophages and the murine macrophage cell line RAW264.7, to elucidate the mechanisms by which HDAC2 modulates endotoxin-induced inflammation.

Results

Results revealed that PAI-1, TNF, and MIP-2 expression were inhibited by theophylline, an HDAC2 enhancer, in a RAW macrophage cell line, following LPS-induced inflammation. Thus, HDAC2 plays an important role in immune defense by regulating the expression of inflammatory genes via the c-Jun/PAI-1 pathway. During LPS-induced inflammation, overexpression of HDAC2 was found to inhibit PAI-1, TNF, and MIP-2 expression. Following LPS stimulation, HDAC2 knockdown increased nuclear translocation and DNA binding of c-Jun to the PAI-1 gene promoter, thereby activating PAI-1 gene transcription. Furthermore, inhibition of PAI-1 by TM5275 alone or in combination with theophylline notably suppressed TNF and MIP-2 expression.

Conclusion

HDAC2 can attenuate lipopolysaccharide-induced inflammation by regulating c-Jun and PAI-1 expression in macrophages.

Comparable Enhanced Prothrombogenesis in Simple Central Obesity and Metabolic Syndrome

OBJECTIVE

There is limited data comparing prothrombogenic or fibrinolysis biomarkers (tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1)) simultaneously in subjects with Metabolic Syndrome (MS), simple central obesity without MS (COB) and normal controls (NC). We investigated the concentrations of fibrinolysis biomarkers in subjects with MS, COB and NC.

METHODS

A cross-sectional study involving 503 drug naive subjects (163 males, aged 30-65 years old (mean age ± SD = 47.4 ± 8.3 years)) divided into MS, COB and NC groups. COB was defined as central obesity (waist circumference (WC) males ≥90 cm, females ≥80 cm) in the absence of MS according to the International Diabetes Federation 2006. Fasting blood levels of tPA and PAI-1were analyzed.

RESULTS

MS and COB had significantly higher concentration of all biomarkers compared to NC. The MS group had significantly higher concentration of tPA and PAI-1 compared to COB. WC and HDL-c had significant correlation with all biomarkers (tPA p < 0.001, PAI-1 p < 0.001). Fasting plasma glucose and diastolic blood pressure were independent predictors after correcting for confounding factors.

CONCLUSION

Central obesity with or without MS both demonstrated enhanced prothrombogenesis. This suggests that simple obesity possibly increases the risk of coronary artery disease in part, via increased susceptibility to thrombogenesis.

Association between plasminogen activator inhibitor-1 and severity of liver injury and cardiovascular risk in children with non-alcoholic fatty liver disease

BACKGROUND

Plasminogen activator inhibitor-1 (PAI-1) is the primary inhibitor of the endogenous fibrinolytic system and is known to be increased in obesity, insulin resistance and non-alcoholic fatty liver disease (NAFLD). We previously demonstrated that PAI-1 levels were closely related to the amount of hepatic steatosis in children.

OBJECTIVES

The aim of this study was to characterize plasma PAI-1 in relationship to severity of inflammation and fibrosis, as well as to plasma lipids in children with NAFLD.

METHODS

In 44 children with NAFLD, plasma PAI-1 levels and lipids were measured at the time of a liver biopsy. Hepatic histological features were systematically scored. Trend analysis was applied to determine the correlation of plasma PAI-1 levels with lipid markers for cardiovascular disease and with the staging of histological features in the liver.

RESULTS

We found that plasma PAI-1 levels were significantly increased in children with increased severity of steatosis, lobular inflammation, ballooning and fibrosis. Furthermore, PAI-1 was strongly correlated with plasma lipids and insulin resistance indices.

CONCLUSIONS

PAI-1 appears to be tightly related to both histologic severity of NAFLD as well as systemic features of the disease including insulin resistance and dyslipidemia. PAI-1 may be a mediator of disease progression and future cardiovascular complications in children with NAFLD.

Implication of Free Fatty Acids in Thrombin Generation and Fibrinolysis in Vascular Inflammation in Zucker Rats and Evolution with Aging

Background: The metabolic syndrome (MetS) and aging are associated with modifications in blood coagulation factors, vascular inflammation, and increased risk of thrombosis. Objectives: Our aim was to determine concomitant changes in thrombin generation in the blood compartment and at the surface of vascular smooth muscle cells (VSMCs) and its interplay with adipokines, free fatty acids (FFA), and metalloproteinases (MMPs) in obese Zucker rats that share features of the human MetS. Methods: Obese and age-matched lean Zucker rats were compared at 25 and 80 weeks of age. Thrombin generation was assessed by calibrated automated thrombography (CAT). Results: Endogenous thrombin potential (ETP) was increased in obese rats independent of platelets and age. Clot half-lysis time was delayed with obesity and age. Interleukin (IL)-1β and IL-13 were increased with obesity and age respectively. Addition of exogenous fibrinogen, leptin, linoleic, or palmitic acid increased thrombin generation in plasma whereas adiponectin had an opposite effect. ETP was increased at the surface of VSMCs from obese rats and addition of exogenous palmitic acid further enhanced ETP values. Gelatinase activity was increased in aorta at both ages in obese rats and MMP-2 activity was increased in VSMCs from obese rats. Conclusions: Our study demonstrated in MetS an early prothrombotic phenotype of the blood compartment reinforced by procoagulant properties of dedifferentiated and inflammatory VSMCs. Mechanisms involved (1) increased fibrinogen and impaired fibrinolysis and (2) increased saturated fatty acids responsible for additive procoagulant effects. Whether specifically targeting this hypercoagulability using direct thrombin inhibitors would improve outcome in MetS is worth investigating.

A null mutation in SERPINE1 protects against biological aging in humans

Plasminogen activator inhibitor-1 (PAI-1) has been shown to be a key component of the senescence-related secretome and a direct mediator of cellular senescence. In murine models of accelerated aging, genetic deficiency and targeted inhibition of PAI-1 protect against aging-like pathology and prolong life span. However, the role of PAI-1 in human longevity remains unclear. We hypothesized that a rare loss-of-function mutation in SERPINE1 (c.699_700dupTA), which encodes PAI-1, could play a role in longevity and metabolism in humans. We studied 177 members of the Berne Amish community, which included 43 carriers of the null SERPINE1 mutation. Heterozygosity was associated with significantly longer leukocyte telomere length, lower fasting insulin levels, and lower prevalence of diabetes mellitus. In the extended Amish kindred, carriers of the null SERPINE1 allele had a longer life span. Our study indicates a causal effect of PAI-1 on human longevity, which may be mediated by alterations in metabolism. Our findings demonstrate the utility of studying loss-of-function mutations in populations with geographic and genetic isolation and shed light on a novel therapeutic target for aging.

Getting Old through the Blood: Circulating Molecules in Aging and Senescence of Cardiovascular Regenerative Cells

Global aging is a hallmark of our century. The natural multifactorial process resulting in aging involves structural and functional changes, affecting molecules, cells, and tissues. As the western population is getting older, we are witnessing an increase in the burden of cardiovascular events, some of which are known to be directly linked to cellular senescence and dysfunction. In this review, we will focus on the description of a few circulating molecules, which have been correlated to life span, aging, and cardiovascular homeostasis. We will review the current literature concerning the circulating levels and related signaling pathways of selected proteins (insulin-like growth factor 1, growth and differentiation factor-11, and PAI-1) and microRNAs of interest (miR-34a, miR-146a, miR-21), whose bloodstream levels have been associated to aging in different organisms. In particular, we will also discuss their potential role in the biology and senescence of cardiovascular regenerative cell types, such as endothelial progenitor cells, mesenchymal stromal cells, and cardiac progenitor cells.

Association of plasminogen activator inhibitor-type 1 (PAI-1) -675 4G/5G polymorphism with unexplained female infertility

BACKGROUND

Infertility is a major issue of concern for couples at reproductive age.  The underlying causes of infertility remain unknown in 15-30 % of the cases. Plasminogen activator inhibitor type 1 (PAI-1), which is a major fibrinolytic factor, has been associated with increased infertility risk.  DNA variants at PAI-1, such as -675 4G/5G promoter polymorphism, have been implicated in infertility-related reproductive disorders, possibly due to a molecular mechanism involving implantation failure. This study aims to investigate the association of PAI-1 4G/5G polymorphism to otherwise unexplained female infertility in a sample of women of Greek ethnic origins.

METHODS

We enrolled in this study 222 women from the population of Northern Greece; 115 women with unexplained infertility (group 1) and 107 normal fertile women (group 2). All participants were genotyped for PAI-1 -675 by real-time polymerase chain reaction.

RESULTS

Our results indicate an association with the PAI-1 4G allele in our sample of women with unexplained infertility. The dominant genetic model supports the association, in contrast to the recessive genetic model.

CONCLUSIONS

Our results indicate that PAI-1 4G/5G polymorphism is a promising screening factor which could potentially be a target for certain cases of unexplained female infertility. However, they should be interpreted with caution and should be validated in larger studies and diverse populations. In addition, other variants in genes involved in thrombophilia might need to be considered. HIPPOKRATIA 2017, 21(4): 180-185.

TM5441, a plasminogen activator inhibitor-1 inhibitor, protects against high fat diet-induced non-alcoholic fatty liver disease

Recent evidences showed that elevation of plasminogen activator inhibitor 1 (PAI-1) was responsible in mediating obesity-induced non-alcoholic fatty liver disease (NAFLD) and metabolic disorders. Here, we investigated the effect of TM5441, an oral PAI-1 inhibitor that lacks of bleeding risk, on high-fat diet (HFD)-induced NAFLD. HFD-fed C57BL/6J mice was daily treated with 20 mg/kg TM5441. To examine the preventive effect, 10-week-treatment was started along with initiation of HFD; alternatively, 4-week-treatment was started in mice with glucose intolerance in the interventional strategy. In vivo study showed that early and delayed treatment decreased hepatic steatosis. Particularly, early treatment prevented the progression of hepatic inflammation and fibrosis in HFD mice. Interestingly, both strategies abrogated hepatic insulin resistance and mitochondrial dysfunction, presented by enhanced p-Akt and p-GSK3β, reduced p-JNK signaling, along with p-AMPK and PGC-1α activation. Consistently, TM5441 treatment in the presence of either PAI-1 exposure or TNF-α stimulated-PAI-1 activity showed a restoration of mitochondrial biogenesis related genes expression on HepG2 cells. Thus, improvement of insulin sensitivity and mitochondrial function was imperative to partially explain the therapeutic effects of TM5441, a novel agent targeting HFD-induced NAFLD.

miR-30c may serve a role in endometriosis by targeting plasminogen activator inhibitor-1

The present study aimed to investigate the role of miR-30c in endometriosis (EMs) and the underlying mechanism. The expression of miR-30c and plasminogen activator inhibitor type 1 (PAI-1) mRNA in EMs tissues was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and the expression of PAI-1 protein was detected by western blot analysis. The proliferation, migration, invasion and adhesion of endometrial stromal cells (ESCs) in different groups transfected with miR-30c mimic or inhibitor were compared. It was demonstrated that miR-30c expression in ectopic and eutopic endometriosis tissues were significantly lower than in normal endometrial tissue. However, PAI-1 mRNA expression in ectopic and eutopic endometrial tissues was higher than in normal endometrial tissues. Furthermore, the expression of PAI-1 protein was higher in ectopic and eutopic endometrosis tissues than in normal tissues. RT-qPCR results indicated that miR-30c expression was significantly increased or decreased in ESCs following transfection of mimic or inhibitor of miR-30c, respectively. Overexpression of miR-30c repressed the expression of PAI-1 mRNA and protein, while inhibition of miR-30c upregulated the expression of PAI-1 in ESCs. In addition, the invasion, migration, proliferation and adhesion of ESCs was repressed following the overexpression of miR-30c, whereas they were promoted when miR-30c expression was downregulated. The results of the present study indicated that miR-30c serves an important role in the development and progression of EMs by regulating the expression of PAI-1.

Evolution and bad prognostic value of advanced glycation end products after acute heart failure: relation with body composition

AIM

The role of advanced glycation end products (AGEs) and their soluble receptor (sRAGE) on the progression and prognosis of acute heart failure (HF) was analysed in relation with metabolic parameters as body composition and nutritional status.

METHODS

A hundred and fifty consecutive patients were included in a prospective clinical study during hospitalization by acute HF. Detailed medical history, physical examination, electrocardiogram, echocardiogram and vein peripheral blood were taken for all patients. During the follow-up period [297 days (88-422 days)] blood samples for biochemical measurements were obtained 1 and 6 months after the inclusion. Dual-energy X-ray absorptiometry analyses were performed 1 week after discharge.

RESULTS

AGEs and sRAGE levels continuously increased, up to 6 months, after acute HF, but AGEs increase was mainly observed in those patients with incident HF. Both AGEs and sRAGE levels were related with bad renal function and clinical malnutrition (CONUT score) and they were negatively related with body mass index or percentage of body fat. AGEs levels (≥40 a.u.) 1 month after discharge and basal sRAGE levels (>1000 pg/mL) were related with worse prognosis in terms of patient death and HF readmission (Log-rank <0.05 in Kaplan-Meier survival test), independently of age, gender, body mass index and other risk factors. Regression models also corroborated this finding.

CONCLUSIONS

AGEs and sRAGE are bad prognostic biomarkers for HF and useful markers of HF progression. Since their levels seem to be related with clinical malnutrition and body composition these parameters could serve to modulate them.

Role of Plasminogen Activator Inhibitor Type 1 in Pathologies of Female Reproductive Diseases

Normal pregnancy is a state of hypercoagulability with diminishing fibrinolytic activity, which is mainly caused by an increase of plasminogen activator inhibitor type 1 (PAI-1). PAI-1 is the main inhibitor of plasminogen activators, including tissue-type plasminogen activator (tPA) and urokinase-type plasminogen activator (uPA). In human placentas, PAI-1 is expressed in extravillous interstitial trophoblasts and vascular trophoblasts. During implantation and placentation, PAI-1 is responsible for inhibiting extra cellular matrix (ECM) degradation, thereby causing an inhibition of trophoblasts invasion. In the present study, we have reviewed the literature of various reproductive diseases where PAI-1 plays a role. PAI-1 levels are increased in patients with recurrent pregnancy losses (RPL), preeclampsia, intrauterine growth restriction (IUGR), gestational diabetes mellitus (GDM) in the previous pregnancy, endometriosis and polycystic ovary syndrome (PCOS). In general, an increased expression of PAI-1 in the blood is associated with an increased risk for infertility and a worse pregnancy outcome. GDM and PCOS are related to the genetic role of the 4G/5G polymorphism of PAI-1. This review provides an overview of the current knowledge of the role of PAI-1 in reproductive diseases. PAI-1 represents a promising monitoring biomarker for reproductive diseases and may be a treatment target in the near future.

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

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.

Plasminogen Activator Inhibitor Type-1 as a Regulator of Fibrosis

Fibrosis is known as a frequent and irreversible pathological condition which is associated with organ failure. Tissue fibrosis is a central process in a variety of chronic progressive diseases such as diabetes, hypertension, and persistent inflammation. This state could contribute to chronic injury and the initiation of tissue repair. Fibrotic disorders represent abnormal wound healing with defective matrix turnover and clearance that lead to excessive accumulation of extracellular matrix components. A variety of identified growth factors, cytokines, and persistently activated myofibroblasts have critical roles in the pathogenesis of fibrosis. Irrespective of etiology, the transforming growth factor-β pathway is the major driver of fibrotic response. Plasminogen activator inhibitor-1 (PAI-1) is a crucial downstream target of this pathway. Transforming growth factor-β positively regulates PAI-1 gene expression via two main pathways including Smad-mediated canonical and non-canonical pathways. Overexpression of PAI-1 reduces extracellular matrix degradation via perturbing the plasminogen activation system. Indeed, elevated PAI-1 levels inhibit proteolytic activity of tissue plasminogen activator and urokinase plasminogen activator which could contribute to a variety of inflammatory elements in the injury site and to excessive matrix deposition. This review summarizes the current knowledge of critical pathways that regulate PAI-1 gene expression and suggests effective approaches for the treatment of fibrotic disease. J. Cell. Biochem. 119: 17-27, 2018. © 2017 Wiley Periodicals, Inc.

Plasminogen activator inhibitor links obesity and thrombotic cerebrovascular diseases: The roles of PAI-1 and obesity on stroke

One of the global socioeconomic phenomena occurred during the last decades is the increased prevalence of obesity, with direct consequence on the risk of developing thrombotic disorders. As the physiological inhibitor of tissue plasminogen activator (tPA) and urokinase plasminogen activator (uPA), plasminogen activator inhibitor-1 (PAI-1) is well known for its role in fibrinolysis. More and more evidences have shown that PAI-1 involves in physiopathologic mechanisms of many diseases and metabolic disorder. Increased serum level of PAI-1 has been observed in obesity and it also contributes to the development of adipose tissue and then has effects on obesity. Meantime, obesity affects also the PAI-1 levels. These evidences indicate the complicated interaction between PAI-1 and obesity. Many clinic studies have confirmed that obesity relates to the stroke outcome although there are many contradictory results. Simultaneously, correlation is found between plasma PAI-1 and thrombotic cerebrovascular diseases. This article reviews contemporary knowledge regarding the complex interplay of obesity, PAI-1 and stroke.

The Role of PAI-1 4G/5G Promoter Polymorphism and Its Levels in the Development of Ischemic Stroke in Young Indian Population

The plasminogen activator inhibitor-1 (PAI-1) gene has been found to be associated with the pathogenesis and progression of vascular diseases including stroke. A 4G/5G, PAI-1 gene polymorphism has been found to be associated with the plasma PAI-1 levels in different ethnic populations but results are still controversial. The aim of this study was to determine the potential association of 4G/5G polymorphism and plasma PAI-1 levels in the development of ischemic stroke (IS) in young Asian Indians. One hundred patients with IS and an equal number of age- and sex-matched controls were studied. The 4G/5G polymorphism was genotyped in the study population through allele-specific polymerase chain reaction. Plasma PAI-1 levels were evaluated using a commercial kit. The PAI-1 levels were significantly higher in patients when compared to the controls ( P = .03). The variant 4G allele for the PAI-I 4G/5G polymorphism showed both genotypic ( P = .0013, χ² = 10.303; odds ratio [OR] = 3.75) as well as allelic association ( P = .0004, χ² = 12.273; OR = 1.99) with IS. The homozygous variant 4G/4G also was found to be associated with the higher PAI-1 levels (0.005). The variant allele 4G of PAI-1 4G/5G polymorphism and higher plasma PAI-1 levels were found to be significantly associated with IS in young Asian Indians.

Associations of hyperglycemia and insulin resistance with biomarkers of endothelial dysfunction in Hispanic/Latino youths: Results from the Hispanic Community Children's Health Study/Study of Latino Youth (SOL Youth)

AIMS

We hypothesized that Hispanic/Latino youth at high risk for diabetes would have elevated biomarkers of endothelial dysfunction.

METHODS

Among 1316 children 8-16years old from the Study of Latino Youth (SOL Youth), we used Poisson regression to obtain prevalence ratios (PRs) and 95% CIs for the cross-sectional association of quartiles of fasting glucose, HbA1c, and insulin resistance with E-selectin and plasminogen activator inhibitor-1 (PAI-1) levels above the median (≥48.1 and ≥2.02ng/mL, respectively).

RESULTS

Levels of E-selectin and PAI-1 were higher in children who were obese or had higher levels of hs-CRP (p<0.05). Insulin resistance was independently associated with higher levels of PAI-1 (adjusted PR and 95% CI for the highest versus lowest quartile (Q4 vs Q1): 2.25 [1.64, 3.09]). We found stronger evidence of associations of insulin resistance with higher levels of PAI-1 among boys as compared with girls (p-interaction = 0.10).

CONCLUSIONS

Insulin resistance was associated with endothelial dysfunction, as measured by higher levels of PAI-1, in Hispanic/Latino youth. These biomarkers may be useful in risk stratification and prediction of diabetes and cardiovascular disease in high-risk youth.

Fibrinolysis inhibitors in plaque stability: a morphological association of PAI-1 and TAFI in advanced carotid plaque

Essentials Fibrinolysis inhibitors are localized in advanced atheroma by immunohistology of endarterectomies. Neovascular endothelium/neocapillaries show thrombin-activatable fibrinolysis inhibitor (TAFI). Macrophage areas show free plasminogen activator inhibitor (PAI-1), notably in the vulnerable part. Free PAI-1 and TAFI stabilize active plaque area by inhibition of fibrinolysis and inflammation.

SUMMARY

Background Fibrinolysis plays an important role in destabilization of atherosclerotic plaques and is tightly regulated by specific inhibitors. Objective The fibrinolysis inhibitors plasminogen activator inhibitor type-1 (PAI-1) and thrombin-activatable fibrinolysis inhibitor (TAFI) were quantified and described in the morphological context of advanced carotid plaques American Heart Association VI-VIII to elucidate their role in plaque stability. Methods Immunohistochemistry in serial sections along the longitudinal axis of endarterectomies from patients with symptomatic carotid stenosis (n = 19) were studied using an antibody specific for free PAI-1 (I205), an antibody with high affinity for TAFI/TAFIa (CP17) and established antibodies for smooth muscle cells (α-actin), endothelial cells (von Willebrand factor [VWF]), macrophages (CD68) and platelets (CD42). Results PAI-1 and TAFI show a specific distribution in these advanced plaques with a maximum corresponding to the internal carotid artery (ICA). Free PAI-1 was mainly detected in macrophages and in intravascular thrombi, and TAFI in endothelial cells (ECs) but also macrophages. The one-way ANOVA analysis with Bonferroni's correction showed a significant increase of macrophages and ECs, TAFI and PAI-1 in areas with high neovascularization in endarterectomy sections corresponding to ICA. High Spearman factors for TAFI, PAI-1 and VWF indicate neovascularization as the main source of plasma proteins, transported by platelets into the atheroma (PAI-1) or expressed by ECs (TAFI). CD68 was highly associated with VWF, PAI-1 and especially TAFI, underlining the role of macrophages in fibrinolytic activity and inflammation. Conclusion The abundance of free PAI-1 and TAFI in the plaque may inhibit plasmin generation and thereby counteract plaque destabilization by fibrinolysis, cell migration and inflammation.

Plasminogen activator inhibitor-1 is elevated in patients with COPD independent of metabolic and cardiovascular function

INTRODUCTION

Plasminogen activator inhibitor-1 (PAI-1), a major inhibitor of fibrinolysis, is associated with thrombosis, obesity, insulin resistance, dyslipidemia, and premature aging, which all are coexisting conditions of chronic obstructive pulmonary disease (COPD). The role of PAI-1 in COPD with respect to metabolic and cardiovascular functions is unclear.

METHODS

In this study, which was nested within a prospective cohort study, the serum levels of PAI-1 were cross-sectionally measured in 74 stable COPD patients (Global Initiative for Chronic Obstructive Lung Disease [GOLD] Stages I-IV) and 18 controls without lung disease. In addition, triglycerides, high-density lipoprotein cholesterol, fasting plasma glucose, waist circumference, blood pressure, smoking status, high-sensitive C-reactive protein (hs-CRP), adiponectin, ankle-brachial index, N-terminal pro-B-type natriuretic peptide, and history of comorbidities were also determined.

RESULTS

The serum levels of PAI-1 were significantly higher in COPD patients than in controls, independent of a broad spectrum of possible confounders including metabolic and cardiovascular dysfunction. A multivariate regression analysis revealed triglyceride and hs-CRP levels to be the best predictors of PAI-1 within COPD. GOLD Stages II and III remained independently associated with higher PAI-1 levels in a final regression analysis.

CONCLUSION

The data from the present study showed that the serum levels of PAI-1 are higher in patients with COPD and that moderate-to-severe airflow limitation, hypertriglyceridemia, and systemic inflammation are independent predictors of an elevated PAI-1 level. PAI-1 may be a potential biomarker candidate for COPD-specific and extra-pulmonary manifestations.

PAI1: a novel PP1-interacting protein that mediates human plasma's anti-apoptotic effect in endothelial cells

Activation of apoptotic signalling in endothelial cells contributes to the detrimental effects of a variety of pathological stimuli. In investigating the molecular events underlying the anti‐apoptotic effect of human plasma in cultured human endothelial cells, we unexpectedly uncovered a novel mechanism of apoptosis suppression by human plasma through an interaction between two previously unrelated proteins. Human plasma inhibited hypoxia–serum deprivation‐induced apoptosis and stimulated BAD^S136 and Akt^S473 phosphorylation. Akt1 silencing reversed part (~52%) of the anti‐apoptotic effect of human plasma, suggesting the existence of additional mechanisms mediating the anti‐apoptotic effect other than Akt signalling. Human plasma disrupted the interaction of BAD with protein phosphatase 1 (PP1). Mass spectrometry identified fourteen PP1‐interacting proteins induced by human plasma. Notably, a group of serine protease inhibitors including plasminogen activator inhibitor 1 (PAI1), a major inhibitor of fibrinolysis, were involved. Silencing of PAI1 attenuated the anti‐apoptotic effect of human plasma. Furthermore, combined Akt1 and PAI1 silencing attenuated the majority of the anti‐apoptotic effect of human plasma. We conclude that human plasma protects against endothelial cell apoptosis through sustained BAD phosphorylation, which is achieved by, at least in part, a novel interaction between PP1 with PAI1.

The beneficial effects of aerobic and concurrent training on metabolic profile and body composition after detraining: a 1-year follow-up in postmenopausal women

BACKGROUND/OBJECTIVES

Aerobic and concurrent training (CT, aerobic and strength training) improves body composition and metabolic profile; however, it is not known whether these positive outcomes acquired after aerobic or CT are maintained long term (⩾6 months) after program interruption in postmenopausal women. This study investigated the changes in total and appendicular body composition, bone mineral density and metabolic profile following 16 weeks of aerobic or CT, and through 6 months and 1 year of detraining in postmenopausal women.

SUBJECTS/METHODS

In total, 60 postmenopausal women were divided into the following groups: aerobic (AT), aerobic plus strength training (CT) and control group (CG), and 31 participants were assessed for the 1 year follow-up. Body composition and bone mineral density were evaluated by dual-energy X-ray absorptiometry (DXA), and total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triacylglycerol, glucose, insulin, leptin, adiponectin and plasminogen activator inhibitor-1 (PAI-1) were assessed.

RESULTS

There were main effects of time for arm fat mass, arm lean mass and trunk lean mass (P<0.05). There was a statistical difference between AT and CG for leg fat mass and percentage of fat (P<0.05). After 6 months of detraining, leg lean mass decreased in relation to post-intervention, and there was a statistically significant interaction for total and appendicular lean mass (P<0.05). There were differences between CT and CG in glucose and between AT and CG in glucose and triacylglycerol (P<0.05).

CONCLUSIONS

A duration of 16 weeks of aerobic or CT improved total and appendicular body composition and metabolic profile but after 6 months of detraining, leg lean mass returned to the values obtained pre-training in CT.

Evaluation of cardiac risk marker levels in obese and non-obese patients with polycystic ovaries

OBJECTIVE

To compare cardiac risk markers such as asymmetric dimethyl arginine (ADMA), C-reactive protein (CRP), homocystein (Hcy), plasminogen activator inhibitor-1 (PAI-1), vascular endothelial growth factor (VEGF), angiopoietin-related growth factor 6 (ANGPTL6) in obese and non-obese patients with polycystic ovary syndrome (PCOS).

STUDY DESIGN

Thirty obese (BMI >30 kg/m²) and 30 non-obese (BMI < 30 kg/m²) patients diagnosed with PCOS and 30 age-matched healthy controls were included in the study. The ages of subjects were varying between 18 and 30 years. Serum ADMA, CRP, Hcy, PAI-1, VEGF and ANGPTL6 levels were analyzed for each subject.

RESULTS

Serum ADMA, CRP, Hcy, PAI-1, VEGF and ANGPTL6 levels were significantly elevated in obese and non-obese women with PCOS in comparison to control subjects (p < 0.05). This elevation was more obvious in the obese PCOS group than in the other group.

CONCLUSIONS

Cardiovascular risk markers such as ADMA, CRP, Hcy, PAI-1, VEGF and ANGPTL6 levels are elevated in women with PCOS.