An antibody that targets cell-surface glucose-regulated protein-78 inhibits expression of inflammatory cytokines and plasminogen activator inhibitors by macrophages.

Glucose-regulated protein-78 (Grp78) is an endoplasmic reticulum chaperone, which is secreted by cells and associates with cell surfaces, where it functions as a receptor for activated α2 -macroglobulin (α2 M) and tissue-type plasminogen activator (tPA). In macrophages, α2 M and tPA also bind to the transmembrane receptor, LDL receptor-related protein-1 (LRP1), activating a cell-signaling receptor assembly that includes the NMDA receptor (NMDA-R) to suppress innate immunity. Herein, we demonstrate that an antibody targeting Grp78 (N88) inhibits NFκB activation and expression of proinflammatory cytokines in bone marrow-derived macrophages (BMDMs) treated with the toll-like receptor-4 (TLR4) ligand, lipopolysaccharide, or with agonists that activate TLR2, TLR7, or TLR9. Pharmacologic inhibition of the NMDA-R or deletion of the gene encoding LRP1 (Lrp1) in BMDMs neutralizes the activity of N88. The fibrinolysis protease inhibitor, plasminogen activator inhibitor-1 (PAI1), has been implicated in diverse diseases including metabolic syndrome, cardiovascular disease, and type 2 diabetes. Deletion of Lrp1 independently increased expression of PAI1 and PAI2 in BMDMs, as did treatment of wild-type BMDMs with TLR agonists. tPA, α2 M, and N88 inhibited expression of PAI1 and PAI2 in BMDMs treated with TLR-activating agents. Inhibiting Src family kinases blocked the ability of both N88 and tPA to function as anti-inflammatory agents, suggesting that the cell-signaling pathway activated by tPA and N88, downstream of LRP1 and the NMDA-R, may be equivalent. We conclude that targeting cell-surface Grp78 may be effective in suppressing innate immunity by a mechanism that requires LRP1 and the NMDA-R.

[Recent advances in the application of TAT, TM, t-PAIC and PIC in thromboembolism].

Thromboembolism is a crucial part of the global disease burden. It has high incidence, high mortality and disability rates, and the mechanism of occurrence and development is extremely complex. It is difficult to detect the disease in the early stage so that we have trouble with clinical prevention and treatment in general. At present, four items of blood coagulation and D-dimer have been widely used in the evaluation and auxiliary diagnosis of thromboembolism, the monitoring of effect for antithrombotic drugs and other fields. The thrombus biomarkers including thrombin-antithrombin complex (TAT), thrombomodulin (TM), tissue plasminogen activator-inhibitor complex (t-PAIC) and α2-plasmin inhibitor-plasmin complex (PIC) fill the gap of laboratory diagnosis before clinical symptoms appear in some degree. This article aims to explain the current application status of TAT, TM, t-PAIC and PIC in thromboembolism and explore their potential application value, so as to provide a reference for selecting appropriate early monitoring indicators for high-risk population of thromboembolism.

Aspirin-triggered proresolving mediators stimulate resolution in cancer.

Inflammation in the tumor microenvironment is a strong promoter of tumor growth. Substantial epidemiologic evidence suggests that aspirin, which suppresses inflammation, reduces the risk of cancer. The mechanism by which aspirin inhibits cancer has remained unclear, and toxicity has limited its clinical use. Aspirin not only blocks the biosynthesis of prostaglandins, but also stimulates the endogenous production of anti-inflammatory and proresolving mediators termed aspirin-triggered specialized proresolving mediators (AT-SPMs), such as aspirin-triggered resolvins (AT-RvDs) and lipoxins (AT-LXs). Using genetic and pharmacologic manipulation of a proresolving receptor, we demonstrate that AT-RvDs mediate the antitumor activity of aspirin. Moreover, treatment of mice with AT-RvDs (e.g., AT-RvD1 and AT-RvD3) or AT-LXA4 inhibited primary tumor growth by enhancing macrophage phagocytosis of tumor cell debris and counter-regulating macrophage-secreted proinflammatory cytokines, including migration inhibitory factor, plasminogen activator inhibitor-1, and C-C motif chemokine ligand 2/monocyte chemoattractant protein 1. Thus, the pro-resolution activity of AT-resolvins and AT-lipoxins may explain some of aspirin's broad anticancer activity. These AT-SPMs are active at considerably lower concentrations than aspirin, and thus may provide a nontoxic approach to harnessing aspirin's anticancer activity.

Hypoxia Promotes Extravillous Trophoblast Cell Invasion through the Hypoxia-Inducible Factor Urokinase-Type Plasminogen Activator Receptor Pathway.

OBJECTIVES: Hypoxia is a common feature of extravillous trophoblast (EVT) cells that promote invasion during the early stages of human placentation. This study aimed to examine whether hypoxia-induced an invasive phenotype in EVT cells in vitro and explore the underlying molecular mechanisms. DESIGN: The invasiveness of primary EVT cells isolated from the first trimester placental tissues during weeks 5-8 of gestation was examined under hypoxic (5% O2) and normoxic (20% O2) conditions. METHODS: Invasiveness was determined by transwell and wound-healing invasion assays using the IncuCyte ZOOM™ Live-Cell Imaging System. Protein expression of the urokinase plasminogen activator (uPA), uPA receptor (uPAR), and plasminogen activator inhibitor of hypoxia or normoxia-treated cells was measured using Western blot analysis. Knockdown of hypoxia-inducible factor-1 alpha (HIF-1α) was assessed using small interfering RNA (siRNA). RESULTS: Hypoxia enhanced EVT cell invasion but did not affect apoptosis. The stimulatory effect of hypoxia on EVT cell invasiveness was associated with induction of the uPA-uPAR pathway. The synthetic inhibitor of uPAR significantly inhibited hypoxia-induced EVT cell invasion. Silencing of HIF-1α by siRNA abolished the stimulatory effect of hypoxia and inhibited the upregulation of uPAR expression, suggesting that the HIF-1α-uPAR signal is the key mediator for hypoxia-induced EVT cell invasion. Further experiments need to be performed to elucidate the HIF-1α-uPAR signal pathways. CONCLUSIONS: The low oxygen-regulated early events of EVT invasion may be mediated by the HIF-1α-uPAR pathway.

The role of fetal fibronectin and plasminogen activator inhibitor 1 biomarkers in antenatal prediction of placenta accreta spectrum.

In this study, we aimed to assess the determining role of foetal fibronectin (FFN) and plasminogen activator inhibitor type (PAI-1) levels in the antenatal prediction of placenta accreta spectrum in cases with risk factors for placenta accreta spectrum. Singleton live pregnancies with placenta previa or low-lying placenta within 32-34 weeks of gestation were included in the study. The cases were divided into two groups after delivery as those with PAS and those with normal placentation. 54 cases diagnosed with placenta previa or low-lying placenta were included in the study. 17 of the cases underwent peripartum hysterectomy due to placenta accreta spectrum. 37 cases with normal placentation underwent caesarean delivery. Foetal fibronectin (p:.03) and PAI-1 (p:.02) levels were determined to be significantly different between cases with placenta accreta spectrum and cases with normal placentation. AUC for foetal FFN was calculated to be 0.69, while the AUC for, PAI-1was 0.66. Results for both FFN and PAI-1 were not found useful enough for the diagnosis of PAS. IMPACT STATEMENTWhat is already known on this subject? We lack biomarkers which can identify placenta accreta spectrum.What do the results of this study add? Maternal plasma levels of FFN and PAI-1 significantly altered in PASWhat are the implications of these findings for clinical practice and/or future research? If multiple of median values of FFN and PAI-1 levels in maternal blood are determined in future studies, it can be used in the antenatal diagnosis of PAS cases.

Trimester-specific reference intervals of TAT, TM, tPAI-C and PIC for healthy Chinese pregnant women.

AIM: Pregnancy is a hypercoagulability state, the aim of this study was to observe the changes of thrombin-antithrombin complex (TAT), thrombomodulin (TM), tissue plasminogen activator-inhibitor complex (tPAI-C) and plasmin-α2-antiplasmin complex (PIC) during pregnancy and establish trimester-specific reference intervals for Chinese healthy pregnant women. METHODS: In total 190 Chinese healthy pregnant women (first trimester 59 cases, second trimester 60 cases and third trimester 71 cases) were recruited in North China. TAT, TM, tPAI-C and PIC were processed on Sysmex HISCL 5000 automated chemiluminescence immune detection system. Trimester-specific reference intervals were established with the 2.5th and 97.5th percentile of the distribution. RESULTS: The reference intervals for TAT, TM, tPAI-C, PIC at trimester 1 were 0.40-3.65 ng/mL, 4.85-8.80 TU/mL, 1.75-6.40 ng/mL, 0.25-1.05 µg/mL, respectively. At trimester 2, the reference intervals were 1.65-8.61 ng/mL, 5.70-9.93 TU/mL, 2.91-7.71 ng/mL, 0.33-2.02 µg/mL, respectively. At trimester 3, the reference intervals were 3.16-12.68 ng/mL, 5.50-14.24 TU/mL, 2.70-10.69 ng/mL, 0.24-1.54 µg/mL, respectively. CONCLUSIONS: The changes of TAT, TM, tPAI-C, PIC during pregnancy are presented, and trimester-specific reference intervals for healthy pregnant women are described. The levels of TAT, TM, tPAI-C were increased gradually from trimester 1 to trimester 3, while the PIC level remains stable during all trimesters.

The Multifaceted Role of Plasminogen in Cancer.

Fibrinolytic factors like plasminogen, tissue-type plasminogen activator (tPA), and urokinase plasminogen activator (uPA) dissolve clots. Though mere extracellular-matrix-degrading enzymes, fibrinolytic factors interfere with many processes during primary cancer growth and metastasis. Their many receptors give them access to cellular functions that tumor cells have widely exploited to promote tumor cell survival, growth, and metastatic abilities. They give cancer cells tools to ensure their own survival by interfering with the signaling pathways involved in senescence, anoikis, and autophagy. They can also directly promote primary tumor growth and metastasis, and endow tumor cells with mechanisms to evade myelosuppression, thus acquiring drug resistance. In this review, recent studies on the role fibrinolytic factors play in metastasis and controlling cell-death-associated processes are presented, along with studies that describe how cancer cells have exploited plasminogen receptors to escape myelosuppression.

Biological mechanisms and individual variation in fibrinolysis after major trauma.

OBJECTIVE: To understand more about the individual variation in the time course of fibrinolysis following major injury and to assess the potential for stratification of trauma patients for tranexamic acid (TXA) therapy. METHODS: A historical dataset (from 2004) was used, consisting of samples from 52 injured patients attended by a medical prehospital system. Blood samples were taken at the incident scene, on arrival in the emergency department, 2.5 hours after hospital arrival and 5 hours after hospital arrival. From the study database, we extracted values for tissue-type plasminogen activator (tPA; an activator of fibrinolysis), one of the plasminogen activator inhibitors (PAI-1; as a natural inhibitor of fibrinolysis) and D-dimer (as a marker of the extent of fibrinolysis). RESULTS: The changes over time in median tPA and PAI-1 were mirror images, with initial high tPA levels which then rapidly decreased and low initial PAI-1 levels which slowly increased. There were high levels of fibrinolytic activity (D-dimer) throughout. This pattern was present in patients across a broad range of injury severities. CONCLUSIONS: After major trauma, there seems to be an early 'antifibrinolytic gap' with the natural antifibrinolytic system lagging several hours behind the natural profibrinolytics. An early dose of exogenous antifibrinolytic (TXA) might have its effect by filling this gap. The finding that tPA and subsequent clot breakdown (illustrated by D-dimer formation) are raised in a broad range of patients, with little correlation between the initial fibrinolytic response and markers of injury severity, may be the reason that TXA is effective across a broad range of injured patients.

Impaired fibrinolysis in degenerative mitral and aortic valve stenosis.

Valvular heart disease is associated with an increased thromboembolic risk. Impaired fibrinolysis was reported in severe aortic stenosis (AS). Little is known about fibrinolysis in mitral stenosis (MS). We sought to compare fibrinolysis impairment in AS and MS. We studied 121 individuals scheduled for elective aortic valve (AV) or mitral valve (MV) surgery for AS (n = 76) or MS (n = 45), in order to compare fibrinolysis impairment. Fibrinolytic capacity was assessed by determination of clot lysis time (t50%) and fibrinolysis inhibitors, including plasma plasminogen activator inhibitor-1 (PAI-1) antigen (PAI-1:Ag) and activity, thrombin-activatable fibrinolysis inhibitor (TAFI) antigen and activity. Prolonged t50% (+ 29%), elevated TAFI activity (+ 12%), TAFI:Ag (+ 21%), and PAI-1:Ag (+ 84%) were observed in patients with MS, compared with those with AS. t50% Correlated with mean and maximal MV gradients (r = 0.43, p < 0.0001 and r = 0.39, p < 0.0001, respectively), but not with AV gradients. Mean and maximal MV gradients correlated with TAFI activity and PAI:Ag. Patients with permanent atrial fibrillation (AF; 35 with MS and 5 with AS) had longer t50% (by 22%, p = 0.0002) and higher PAI-1:Ag (by 74%, p < 0.0001) than the remainder. In the whole group, postoperative drainage volumes correlated inversely with PAI-1:Ag (r = - 0.22, p = 0.02). MS is associated with more pronounced impairment of global fibrinolytic capacity than AS at the stage of surgical intervention, which is in part driven by AF. Our findings suggest that hypofibrinolysis might be implicated in the progression of MS and its thromboembolic complications.

Urokinase-type plasminogen activator modulates mammalian circadian clock phase regulation in tissue-type plasminogen activator knockout mice.

Glutamate phase shifts the circadian clock in the mammalian suprachiasmatic nucleus (SCN) by activating NMDA receptors. Tissue-type plasminogen activator (tPA) gates phase shifts by activating plasmin to generate m(ature) BDNF, which binds TrkB receptors allowing clock phase shifts. Here, we investigate phase shifting in tPA knockout (tPA-/- ; B6.129S2-Plattm1Mlg /J) mice, and identify urokinase-type plasminogen activator (uPA) as an additional circadian clock regulator. Behavioral activity rhythms in tPA-/- mice entrain to a light-dark (LD) cycle and phase shift in response to nocturnal light pulses with no apparent loss in sensitivity. When the LD cycle is inverted, tPA-/- mice take significantly longer to entrain than C57BL/6J wild-type (WT) mice. SCN brain slices from tPA-/- mice exhibit entrained neuronal activity rhythms and phase shift in response to nocturnal glutamate with no change in dose-dependency. Pre-treating slices with the tPA/uPA inhibitor, plasminogen activator inhibitor-1 (PAI-1), inhibits glutamate-induced phase delays in tPA-/- slices. Selective inhibition of uPA with UK122 prevents glutamate-induced phase resetting in tPA-/- but not WT SCN slices. tPA expression is higher at night than the day in WT SCN, while uPA expression remains constant in WT and tPA-/- slices. Casein-plasminogen zymography reveals that neither tPA nor uPA total proteolytic activity is under circadian control in WT or tPA-/- SCN. Finally, tPA-/- SCN tissue has lower mBDNF levels than WT tissue, while UK122 does not affect mBDNF levels in either strain. Together, these results suggest that either tPA or uPA can support photic/glutamatergic phase shifts of the SCN circadian clock, possibly acting through distinct mechanisms.

The Role of Plasminogen Activator Inhibitor Type-1 in Fibrosis.

Extracellular matrix (ECM) deposition during wound healing is a physiological response to an insult. Wound healing becomes deregulated in the setting of chronic injury or long-standing metabolic disease, leading to the accumulation of ECM components and fibrosis. Matrix protein turnover is determined by the rate of synthesis as well as the rate of proteolytic degradation and clearance by matrix metalloproteinases (MMPs). The persistent activation of interstitial myofibroblasts, coupled with defects in matrix proteolysis, ultimately disrupts tissue architecture and leads to biochemical and mechanical organ dysfunction with eventual organ failure. Plasminogen activator inhibitor type-1 (PAI-1) regulates tissue homeostasis and wound healing by inhibiting plasmin-mediated MMP activation. Multiple reports using models of liver, lung, and kidney fibrosis suggest that PAI-1 deficiency or inhibition of PAI-1 activity attenuates fibrosis. The disinhibition of plasmin-mediated MMP activation leads to collagen degradation and its diminished accumulation, resulting in the reduction of fibrotic matrix deposition in these organs. Paradoxically, homozygous deficiency of PAI-1 promotes age-dependent spontaneous cardiac fibrosis, suggesting a protective role for PAI-1 in the heart. It remains unclear whether PAI-1-deficient cardiac fibroblasts have increased proliferative, migratory, or differentiation capabilities, that allow them to overcome increased plasmin and MMP activity and matrix clearance. In this review, we examine the specific roles of PAI-1 in fibrosis of different organs including the lung, liver, kidney, and cardiovascular system.

Therapeutic potential of an orally effective small molecule inhibitor of plasminogen activator inhibitor for asthma.

Asthma is one of the most common respiratory diseases. Although progress has been made in our understanding of airway pathology and many drugs are available to relieve asthma symptoms, there is no cure for chronic asthma. Plasminogen activator inhibitor 1 (PAI-1), a primary inhibitor of tissue-type and urokinase-type plasminogen activators, has pleiotropic functions besides suppression of fibrinolysis. In this study, we show that administration of TM5275, an orally effective small-molecule PAI-1 inhibitor, 25 days after ovalbumin (OVA) sensitization-challenge, significantly ameliorated airway hyperresponsiveness in an OVA-induced chronic asthma model. Furthermore, we show that TM5275 administration significantly attenuated OVA-induced infiltration of inflammatory cells (neutrophils, eosinophils, and monocytes), the increase in the levels of OVA-specific IgE and Th2 cytokines (IL-4 and IL-5), the production of mucin in the airways, and airway subepithelial fibrosis. Together, the results suggest that the PAI-1 inhibitor TM5275 may have therapeutic potential for asthma through suppressing eosinophilic allergic response and ameliorating airway remodeling.

Increased plasminogen activator inhibitor results in a hypofibrinolytic state in adolescents with obesity: in vivo and ex vivo evidence.

Obesity in adolescents increases their risk for deep vein thrombosis. The objectives of this study were to determine potential mechanisms for thrombotic risk by investigating the fibrinolytic pathway in a sample of adolescents with and without obesity. Thirty-seven adolescents with obesity and 16 normal weight age-matched controls were recruited. Plasma levels of components of the fibrinolytic system were measured in addition to a Global Haemostasis Potential assay (GHP), which assesses plasma capacity to generate and lyse a fibrin clot. Levels of plasminogen activator inhibitor (PAI) and tissue plasminogen activator (tPA)/PAI complexes were increased in adolescents with obesity when compared to normal weight controls. There was a significant inverse association of increasing PAI with a decrease in plasmin-antiplasmin complexes. The GHP in obese adolescents displayed a hypofibrinolytic response with a markedly increased t½ clot lysis time, as well as an increase in fibrin clot density as indicated by increased absorbance at maximum peak height. In the obese group, immunodepletion of PAI decreased both t½ lysis time and absorbance at maximum peak height. We have shown in vivo and ex vivo there is a hypofibrinolytic state in obese adolescents and have established the hypofibrinolytic state is due to increased PAI levels.

Differences during the first lactation between cows cloned by somatic cell nuclear transfer and noncloned cows.

Lactation performance is dependent on both the genetic characteristics and the environmental conditions surrounding lactating cows. However, individual variations can still be observed within a given breed under similar environmental conditions. The role of the environment between birth and lactation could be better appreciated in cloned cows, which are presumed to be genetically identical, but differences in lactation performance between cloned and noncloned cows first need to be clearly evaluated. Conflicting results have been described in the literature, so our aim was to clarify this situation. Nine cloned Prim' Holstein cows were produced by the transfer of nuclei from a single fibroblast cell line after cell fusion with enucleated oocytes. The cloned cows and 9 noncloned counterparts were raised under similar conditions. Milk production and composition were recorded monthly from calving until 200d in milk. At 67d in milk, biopsies were sampled from the rear quarter of the udder, their mammary epithelial cell content was evaluated, and mammary cell renewal, RNA, and DNA were then analyzed in relevant samples. The results showed that milk production did not differ significantly between cloned and noncloned cows, but milk protein and fat contents were less variable in cloned cows. Furthermore, milk fat yield and contents were lower in cloned cows during early lactation. At around 67 DIM, milk fat and protein yields, as well as milk fat, protein, and lactose contents, were also lower in cloned cows. These lower yields could be linked to the higher apoptotic rate observed in cloned cows. Apoptosis is triggered by insulin-like factor growth binding protein 5 (IGFBP5) and plasminogen activator inhibitor (PAI), which both interact with CSN1S2. During our experiments, CSN1S2 transcript levels were lower in the mammary gland of cloned cows. The mammary cell apoptotic rate observed in cloned cows may have been related to the higher levels of DNA (cytosine-5-)-methyltransferase 1 (DNMT1) transcripts, coding for products that maintain the epigenetic status of cells. We conclude, therefore, that milk production in cloned cows differs slightly from that of noncloned cows. These differences may be due, in part, to a higher incidence of subclinical mastitis. They were associated with differences in cell apoptosis and linked to variations in DNMT1 mRNA. However, milk protein and fat contents were more similar among cloned cows than among noncloned cows.

Effects of addition of tissue-type plasminogen activator in in vitro fertilization medium on bovine embryo development and quality.

Plasminogen activators/Plasmin system plays pivotal role in regulating reproductive functions of mammals. Here, we examined the effects of modification of in vitro fertilization medium (IVF medium) with the addition of tissue-type plasminogen activator (t-PA), on bovine embryo development and quality, assessed by quantification of expression of various genes related to metabolism, oxidation, implantation and apoptosis. In addition, plasminogen activator activity (PAA) and plasminogen activator inhibition (PAI) were measured in the spent media. After conventional IVM, 2016 cumulus-oocyte complexes (COCs) were divided into four groups with modified composition of the IVF medium containing t-PA and/or its inhibitor epsilon-aminocaproic acid (control, t-PA, t-PA+ε-ACA, ε-ACA). Presumptive zygotes were cultured for 8 days in synthetic oviductal fluid (SOF) medium; gene expression studies were carried out on morulae and blastocysts. t-PA alone significantly suppressed cleavage and blastocyst formation rates, but this effect was neutralized by the addition of ε-ACA. PAA in the treated group was significantly reduced by ε-ACA, but without total elimination. Significant differences were detected in the expression of genes related to apoptosis and/or cell cycle arrest (BAX, BCL2L1, KAT2B) between embryos produced in t-PA-modified media and controls, giving an overall notion that the inferior developmental competence of treated embryos may be attributed to apoptotic phenomena induced by t-PA. In conclusion, it appears that excessive t-PA content in the IVF media, suppresses blastocyst formation rate, possibly due to induction of apoptotic phenomena.

Cytotoxicity of the Urokinase-Plasminogen Activator Inhibitor Carbamimidothioic Acid (4-Boronophenyl) Methyl Ester Hydrobromide (BC-11) on Triple-Negative MDA-MB231 Breast Cancer Cells.

BC-11 is an easily synthesized simple thiouronium-substituted phenylboronic acid, which has been shown to be cytotoxic on triple negative MDA-MB231 breast cancer cells by inducing a perturbation of cell cycle when administered at a concentration equal to its ED50 at 72 h (117 µM). Exposure of cells to BC-11, either pre-absorbed with a soluble preparation of the N-terminal fragment of urokinase-plasminogen activator (uPa), or in co-treatment with two different EGFR inhibitors, indicated that: (i) BC-11 acts via binding to the N-terminus of the enzyme where uPa- and EGF receptor-recognizing sites are present, thereby abrogating the growth-sustaining effect resulting from receptor binding; and (ii) the co-presence of the EGFR inhibitor PD153035 potentiates BC-11's cytotoxicity. Exposure of cells to a higher concentration of BC-11 corresponding to its ED75 at 72 h (250 µM) caused additional impairment of mitochondrial activity, the production of reactive oxygen species and promotion of apoptosis. Therefore, BC-11 treatment appears to show potential for the development of this class of compounds in the prevention and/or therapy of "aggressive" breast carcinoma.

[Streptokinase and Staphylokinase: Differences in the Kinetics and Mechanism of Their Interaction with Plasminogen, Inhibitors and Fibrin].

Comparative in vitro study of the kinetics of various reactions involved in the process of thrombolysis initiated by streptokinase (SK) and staphylokinase (STA) was carried out. It was shown that at the interaction of an equimolar ratio of plasminogen (Pg) with SK or STA the rate of formation and the specific esterase activity of the complex plasmin (Pm) · SK are higher than those of the complex Pm · STA. The catalytic efficiency (kcat/Km) of hydrolysis of the chromogenic plasmin substrates by Pm · SK complex was 2 times higher than by Pm · STA complex. In the absence of fibrin catalytic efficiency (kPg/K(Pg)) of activation of Glu-plasminogen and Lys-plasminogen glycoform II by Pm · SK complex was higher than by Pm · STA complex, but the pres- ence of fibrin increased kPg/K(Pg)) activation of both plasminogens by Pm · STA complex significantly stronger than by Pm · SK complex due to the decrease in K(Pg)). In contrast to STA (15.5 kDa), SK molecule (47 kDa) creates significant steric hindrances for the interaction of plasmin in Pm · SK complex with protein inhibi- tors. In addition, SK caused greater fibrinogen degradation than STA. It is shown that Pm · SK and Pm · STA complexes lyse fibrin clots in buffer with similar rates, while the rate of lysis of plasma clots, immersed in plas- ma, by Pm · STA complex are significantly higher than those by Pm · SK complex. It was revealed that the species specificity of STA and S K is determined mainly by the rate of formation and the efficiency of Pm · SK and Pm · STA complexes in the activation of autologous plasminogen. The lysis efficiency of plasma clots of mammals fell in the series: human > dog > rabbit for SK and the dog > human > rabbit for STA. The results show that in the purified system SK is a more effective activator of plasminogen than STA. In the system con- taining fibrin and α2-AP, the activator and fibrinolytic activities of STA are higher than those of SK, due to the increased stability in plasma and fibrin specificity of STA, the fast reaction of the complex Pm · STA with α2AP and the ability of the STA to recyclization in the presence of α2AP.

Hypercoagulability panel testing predicts thrombosis in neonates undergoing cardiac surgery.

Thrombosis contributes to morbidity and mortality in neonates following cardiac surgery. Alterations in hemostatic factors following cardiac surgery have been described, but there is no data correlating these changes with risk of thrombosis in neonates. The aim of this study is to predict thrombosis in neonates undergoing cardiac surgery by assessment of a panel of hypercoagulability markers. Neonates undergoing cardiac surgery were enrolled preoperatively and prospectively followed. Preoperative hypercoagulability panel testing included thrombin generation assay (TGA), immunoassays for antithrombin III, protein C, protein S, factor VIII, thrombin-activatable fibrinolytic inhibitor (TAFI), plasminogen activator inhibitor-1 (PAI-1), and cardiolipin antibody. Postoperative thrombosis was defined by clinical events (shunt thrombosis, limb ischemia, and stroke) or imaging (intravascular or intracardiac thrombus). Risk factors for thrombosis were assessed. One hundred neonates were enrolled in the study over a two-year period. The incidence of postoperative in-hospital thrombosis was 20%. The only significant clinical risk factor associated with thrombosis was the single ventricle physiology. Hypercoagulability factors associated with increased risk of thrombosis by univariate analysis were elevated PAI-1, TAFI, and TGA, and presence of anticardiolipin antibodies. Multivariable logistic regression analysis demonstrated that elevated PAI-1 (P = 0.015), TAFI (P = 0.028), and TGA (P = 0.007) were independent predictors of thrombosis. Hypercoagulability panel testing may help identify neonates at high risk for thrombosis following cardiac surgery. Future studies are warranted to determine if high risk patients benefit from targeted anticoagulation therapies.

Prevention of experimental postoperative peritoneal adhesions through the intraperitoneal administration of tanshinone IIA.

Postoperative adhesions develop after nearly every abdominal surgery. The formation of adhesions is associated with the inflammatory response, fibrinolytic system, and extracellular matrix deposition in response to injury. Tanshinone IIA is one of the major extracts obtained from Salvia miltiorrhiza, which has anti-inflammatory effects on many diseases. Postoperative adhesions were induced by injuring the parietal peritoneum and cecum in Wistar rats, followed by the administration of various dosages of tanshinone IIA. The adhesion scores for each group were collected seven days after the initial laparotomy. The activity of the tissue-type plasminogen activator in the peritoneal lavage fluid was measured. The messenger ribonucleic acid expression levels of the tissue-type plasminogen activator, plasminogen activator inhibitor-1, and cyclooxygenase-2 in the ischaemic tissues were measured by quantitative real-time polymerase chain reaction. The intraperitoneal administration of tanshinone IIA is effective for the prevention of the formation of postoperative adhesions in rats. Tanshinone IIA increased fibrinolytic activity in the peritoneal lavage fluid and tissue-type plasminogen activator messenger ribonucleic acid expression in ischaemic peritoneal tissues but decreased the plasminogen activator inhibitor and cyclooxygenase-2 messenger ribonucleic acid expression significantly. These results revealed that tanshinone IIA was a potent postoperative adhesion preventer by enhancing fibrinolytic activity and decreasing cyclooxygenase-2 activity.

Circulating apelin levels are associated with cardiometabolic risk factors in women with previous gestational diabetes.

PURPOSE: Women with previous gestational diabetes mellitus (pGDM) are at high risk for type 2 diabetes and cardiovascular disorders. In this study, we aimed to compare plasma apelin levels between women with and without pGDM, and to investigate the possible association of apelin with cardiometabolic risk factors. METHODS: Among 252 consecutive Caucasian women with GDM being included in a prospective postpartum follow-up protocol, 141 women eligible for the study protocol were enrolled. Control group consisted of 49 age- and body mass index-matched healthy women without pGDM. Circulating apelin, IL-6 and plasminogen activator inhibitor levels, and carotid intima media thickness (IMT) were measured. To evaluate carbohydrate intolerance, 75-g oral glucose tolerance test was performed. Fasting insulin and lipids were measured, and homeostasis model assessment index was calculated. RESULTS: Plasma apelin levels were reduced in women with pGDM (p < 0.001). In multiple regression analysis, apelin was negatively associated with fasting (r (2) 0.090, ß -0.273, p = 0.001) and post-load glucose (r (2) 0.061, ß -0.187, p = 0.022), serum IL-6 (r (2) 0.082, ß -0.234, p = 0.002), and carotid IMT (r (2) 0.057, ß -0.168, p = 0.033). CONCLUSIONS: Our results suggested that suppressed apelin levels were associated with increased cardiovascular risk in women with pGDM.