tPA Levels Research Articles

Prognostic value of tissue plasminogen activator (tPA) in patients with epithelial ovarian cancer undergoing chemotherapy.

Tissue plasminogen activator (tPA) is a key enzyme for fibrin degradation and the proteolytic defense against formation of the thrombotic endothelial deposits. tPA is involved in carcinogenesis but its exact role in tumor biology is not very well understood and a prognostic value of tPA remains ambiguous in different cancers. The aim of the study was to assess the prognostic value of plasma tPA in patients with epithelial ovarian cancer (EOC) in the course of the first line chemotherapy. the study covered 60 patients with EOC who underwent the 1st line chemotherapy. Plasma tPA was assessed at onset, after 3 and 6 cycles of chemotherapy. The groups were stratified according to tPA level at onset of chemotherapy (low tPA group < 6.5 mg/L, N = 37 and high tPA group > 6.5 mg/L, N = 23). Survival analysis was repeated for the cut-off of tPA level at 6.5 mg/L and 5.1 mg/L after 3 and 6 cycles. Only subjects with tPA > 6.5 mg/L at onset of chemotherapy had a significantly lower probability of a 5-year survival (34.8% vs. 72.7%, P < 0.006) and lower chance for disease free survival within 5 years (39.3% vs. 72.7%, P < 0.014). tPA < 6.5 mg/L plasma level evaluated at onset of chemotherapy was an independent marker of better overall survival (RR = 0.44, 95%CI = 0.19-0.98) but not disease-free survival. Plasma tPA may serve as a marker of survival if assessed at onset of the first line chemotherapy in patients with ovarian cancer.

TPA and PAI-1 in malignant tissues of gastric adenocarcinoma can be tumor-associated.

e15533 Background: Plasminogen regulator system is considered to be involved in migration, invasion and proliferation of malignant cells. The role of tissue plasminogen activator (tPA) and PAI-1 in cancer is still discussed. Our purpose was to study the antigen and active forms of tPA and PAI-1 (tPA-Ag, tPA-act and PAI-1-Ag, PAI-1-act) in tissues of gastric adenocarcinoma (GA), greater omentum and peritoneum with and without metastases (mts). Methods: We studied tissues of patients with GA T3-4аN0-3M1 (n = 21, 10 men, 11 women) and T3-4аN0-3M0 (n = 24, 15 men, 9 women) aged 61.23±4.8 years. Control group included 17 non-cancer patients aged 39.1±3.2 years (6 men, 11 women). Levels of tPA-act, tPA-Ag, PAI-1-act and PAI-1-Ag were measured by ELISA using standard test systems. Statistical analysis was performed using the SPSS 11.5 software package for Windows. Results: Levels of both forms of tPA and PAI-1 in GA with and without mts were 1-2 orders of magnitude higher than in resection line tissues. Levels of tPA-Ag and PAI-1-Ag in GA without mts were 1.7 and 2.5 times higher than in GA with mts, while levels of tPA-act and PAI-1-act were similar. In tissues of the greater omentum, levels of tPA-Ag with mts exceeded that in tissues without mts and in controls by 5.0 and 1.7 times, respectively; levels of tPA-act were similar to controls, while without mts they were 1.6 times lower than in controls. PAI-1-Ag with mts was 3.2 and 4.5 without mts and in controls, respectively; PAI-1-act with mts was 1.8 and 1.5 times higher than in controls and without mts, respectively. In tissues of the peritoneum, tPA-Ag with mts was 1.6 and 1.4 times higher than without mts and in controls, respectively; tPA-act with and without mts was 1.4 (p = 0.0412) and 1.5 times lower than in controls. PAI-1-Ag in the peritoneum with and without mts 1.4 times (p = 0.0428) exceeded control, and PAI-1-act was higher than in controls by 1.6 and 2.8 times, respectively. The results demonstrated that GA with and without mts secreted PAI-1 and tPA, and levels of tPA-Ag and both forms of PAI-1 were elevated in tissues of the peritoneum and omentum with and without mts. Conclusions: Levels of tPA-Ag and both forms of PAI-1 in the greater omentum and peritoneum without mts indicate possible formation of a pre-metastatic niche.

Tissue plasminogen activator in gastrointestinal adenocarcinoma: What is its role?

e15532 Background: The aim of the study was a comparative analysis of the tissue plasminogen activator activity (tPA-Ag and tPA-act) in adenocarcinoma of the esophagus (EA), stomach (SA), pancreatic head (PHA), sigmoid colon (SCA) and rectum (RA). Methods: Tissues of tumors, perifocal area (PA) and resection line tissues were studied by ELISA in 143 patients (38-74 years) with EC (n = 12, G2, T2-3N0-1M0), SC (n = 28, G2, T2-3N0-1M0), PHC (n = 46, G2, Т2-4N0M0), SCC (n = 31, G2, T2-3N0-1M0) and RC (n = 26, G2, T2-3N0-1M0). Statistical analysis was performed using the Statistica 10 program. Results: Tumor levels of tPA-Ag were the highest in SA: SA˃RA˃SCA˃EA˃PHA, but in EA, SCA and RA were lower than in the resection line (p &lt; 0.01). Tumor levels of tPA-Ag in SA were similar to the values in PA, and were 3.1-213 times higher than in other tumors. Perifocal levels of tPA-Ag were the highest in SA: SA˃SCA and RA˃EA˃PHA, but in EA and PHA they were lower than in the resection line tissues (p &lt; 0.01), in SCA and RA – similar, in SA – exceeded the levels in all samples by 1-2 orders of magnitude (p &lt; 0.0001). Levels of tPA-Ag were similar in resection line tissues in SCA and RA, being 2.5-128 times higher than in other tumors. The highest tPA-act was observed in perifocal and tumor tissues in SA (p &lt; 0.0001, compared to other tumors): SA˃SCA˃RA˃EA˃PHA (p &lt; 0.01). tPA-act in PHA tumors was 1.3 times higher (p &lt; 0.05) than in resection line tissues and 40.5 times lower than in PA. In SCA, tPA-act was similar in tumor and PA, but was 1.3 times lower (p &lt; 0.05) than in resection line tissues. In RA, tPA-act decreased from the resection line to the tumor by 1.3 and 2.3 times, respectively. Conclusions: The role of tPA in gastrointestinal adenocarcinomas differs: in EA, SCA and RA it has protective functions, as its levels in the tumor are lower than in the resection line. SA was accompanied by an enhanced secretion of tPA-Ag and the formation of tPA-act in tumors, with their subsequent evasion into PA. In PHA, the tPA distribution was similar, but the high rate of tPA activation led to the depletion of both forms of tPA, while still retaining their advantage in the tumor and PA, compared with the resection line.

Role of tissue plasminogen activator and plasminogen activator inhibitor as potential biomarkers in psychosis.

The identification of biological markers for psychosis has an impact on its diagnosis, prognosis, and likelihood of treatment response. Tissue plasminogen activator (tPA) is involved in important functions such as synaptic plasticity, long-term potentiation and neurogenesis. Plasminogen activator inhibitor (PAI-1) is the most important inhibitor of tPA. Preliminary studies have shown that schizophrenia patients have lower tPA and higher PAI-1 levels than the general population. The association of tPA and PAI-1 abnormalities with psychotic spectrum disorders, however, remains elusive. Our primary objective was to assess the plasma levels of tPA and PAI-1 in patients experiencing acute psychotic episodes as compared to those in healthy controls. In this prospective case-control study, we collected peripheral blood samples from psychiatric inpatients and healthy age, gender and race-matched subjects and determined plasma levels of tPA and PAI-1 by enzyme-linked immune-absorbent assays. Plasma levels of PAI-1 in patients with schizoaffective disorder were significantly lower as compared to those in control subjects (P = 0.03). tPA was lower in cases as compared to controls although it did not reach statistical significance. Asian patients and controls had lower PAI-1 levels. Further, Asian patients with schizoaffective disorder had significantly lower PAI-1 level compared to Asian patients with schizophrenia. Our results indicate that patients with schizoaffective disorder have lower PAI-1 levels than those with schizophrenia, affective psychosis, and healthy controls. Further studies are warranted to explore the potential of PAI-1 as a biomarker for diagnosing schizoaffective disorder.

Effect of dermatan sulphate on a C57-mouse model of pulmonary fibrosis.

ObjectiveTo test the antifibrotic effect of dermatan sulphate in a bleomycin-induced mouse model of pulmonary fibrosis.MethodsC57 mice were randomly divided into four experimental groups: saline-treated control group, bleomycin-induced fibrosis group, prednisolone acetate group and dermatan sulphate group. Lungs were assessed using the lung index, and the extent of interstitial fibrosis was graded using histopathological observation of haematoxylin & eosin-stained lung tissue. Lung tissue hydroxyproline levels and blood fibrinogen levels were measured using a hydroxyproline colorimetric kit and the Clauss fibrinogen assay, respectively. Tissue-type plasminogen activator (tPA) was measured using a chromogenic tPA assay kit.ResultsLung index values were significantly lower in the dermatan sulphate group versus the fibrosis group. Histopathological analyses revealed that dermatan sulphate treatment ameliorated the increased inflammatory cell infiltration, and attenuated the reduction in interstitial thickening, associated with bleomycin-induced fibrosis. Hydroxyproline and fibrinogen levels were decreased in the dermatan sulphate group versus the fibrosis model group. Dermatan sulphate treatment was associated with increased tPA levels versus controls and the fibrosis group.ConclusionsDamage associated with bleomycin-induced pulmonary fibrosis was alleviated by dermatan sulphate.

Learning and memory deficits and alzheimer's disease-like changes in mice after chronic exposure to microcystin-LR.

Previous studies have demonstrated that toxins produced by toxic cyanobacterial blooms are hazardous materials. Although microcystin-LR (MC-LR) has been revealed to inflict damage to the brain, the mechanisms underlying its neurotoxicity as a result of chronic exposure to MC-LR are not fully described. In this study, the mice were exposed to MC-LR dissolved in drinking water at doses of 1, 7.5, 15, or 30 μg/L for 180 days. MC-LR accumulated mostly in the mouse hippocampus (55 ng/g dry weight) followed by cortex (28 ng/g dry weight) after exposure to MC-LR at 30 μg/L. MC-LR exposure at this concentration induced dysfunction of learning and memory, accompanied with apoptosis of neuronal cells (with 10% reduction of the neurons in the CA1 region and 15% in the CA2 region), reduction of spine density, accumulation of β-amyloid plaques 1-42 (Aβ1-42), and enhanced phosphorylation of tau (p-tau) in the brain, which is characteristic of Alzheimer's disease (AD). These data indicate that MC-LR may induce AD-like pathology. Following prolonged exposure, MC-LR significantly upregulated the ratio of proBDNF to BDNF by downregulating the tPA levels, thereby activating downstream signaling pathways to improve the expression of p-JNK, and c-Jun while to inhibit the expression of p-Creb and p-PKC. This study uncovered new molecular mechanisms that account for neurotoxicity after chronic exposure to MC-LR, which has wide-ranging implications for public health.

Mathematical Modelling of Intravenous Thrombolysis in Acute Ischaemic stroke: Effects of Dose Regimens on Levels of Fibrinolytic Proteins and Clot Lysis Time.

Thrombolytic therapy is one of the medical procedures in the treatment of acute ischaemic stroke (AIS), whereby the tissue plasminogen activator (tPA) is intravenously administered to dissolve the obstructive blood clot. The treatment of AIS by thrombolysis can sometimes be ineffective and it can cause serious complications, such as intracranial haemorrhage (ICH). In this study, we propose an efficient mathematical modelling approach that can be used to evaluate the therapeutic efficacy and safety of thrombolysis in various clinically relevant scenarios. Our model combines the pharmacokinetics and pharmacodynamics of tPA with local clot lysis dynamics. By varying the drug dose, bolus-infusion delay time, and bolus-infusion ratio, with the FDA approved dosing protocol serving as a reference, we have used the model to simulate 13 dose regimens. Simulation results are compared for temporal concentrations of fibrinolytic proteins in plasma and the time that is taken to achieve recanalisation. Our results show that high infusion rates can cause the rapid degradation of plasma fibrinogen, indicative of increased risk for ICH, but they do not necessarily lead to fast recanalisation. In addition, a bolus-infusion delay results in an immediate drop in plasma tPA concentration, which prolongs the time to achieve recanalisation. Therefore, an optimal administration regimen should be sought by keeping the tPA level sufficiently high throughout the treatment and maximising the lysis rate while also limiting the degradation of fibrinogen in systemic plasma. This can be achieved through model-based optimisation in the future.

Increased 5-HT2C receptor editing predisposes to PTSD-like behaviors and alters BDNF and cytokines signaling

Post-traumatic stress disorder (PTSD) is a trauma- and stress-related disorder with dysregulated fear responses and neurobiological impairments, notably at neurotrophic and inflammation levels. Understanding the mechanisms underlying this disease is crucial to develop PTSD models that meet behavioral and neurobiological validity criteria as well as innovative therapeutic approaches. Serotonin 2C receptors (5-HT2CR) are known for their important role in anxiety, and mice having only the fully edited VGV isoform of 5-HT2CR, which thereby overexpressed brain 5-HT2CR, are of special interest to study PTSD predisposition. Innate and conditioned fear-related behaviors were assessed in VGV and wild-type mice. mRNA expression of brain-derived neurotrophic factor (BDNF), tissue-plasminogen activator (tPA), and pro-inflammatory cytokines (IL-6, IL-1β, and calcineurin) were measured by qRT-PCR. The effect of acute and chronic paroxetine was evaluated on both behavior and gene expression. VGV mice displayed greater fear expression, extensive fear extinction deficits, and fear generalization. Paroxetine restored fear extinction in VGV mice when administered acutely and decreased innate fear and fear generalization when administered chronically. In parallel, Bdnf, tPA, and pro-inflammatory cytokines mRNA levels were dysregulated in VGV mice. Bdnf and tPA mRNA expression was decreased in the hippocampus but increased in the amygdala, and chronic paroxetine normalized Bdnf mRNA levels both in the amygdala and the hippocampus. Amygdalar calcineurin mRNA level in VGV mice was also normalized by chronic paroxetine. VGV-transgenic mice displayed behavioral and neurobiological features that could be accessory to the investigation of PTSD and its treatment. Furthermore, these data point out to the role of 5-HT2CR in neuroplasticity and neuroinflammation.

An ATF6-tPA pathway in hepatocytes contributes to systemic fibrinolysis and is repressed by DACH1

AbstractTissue-type plasminogen activator (tPA) is a major mediator of fibrinolysis and, thereby, prevents excessive coagulation without compromising hemostasis. Studies on tPA regulation have focused on its acute local release by vascular cells in response to injury or other stimuli. However, very little is known about sources, regulation, and fibrinolytic function of noninjury-induced systemic plasma tPA. We explore the role and regulation of hepatocyte-derived tPA as a source of basal plasma tPA activity and as a contributor to fibrinolysis after vascular injury. We show that hepatocyte tPA is downregulated by a pathway in which the corepressor DACH1 represses ATF6, which is an inducer of the tPA gene Plat. Hepatocyte-DACH1–knockout mice show increases in liver Plat, circulating tPA, fibrinolytic activity, bleeding time, and time to thrombosis, which are reversed by silencing hepatocyte Plat. Conversely, hepatocyte-ATF6–knockout mice show decreases in these parameters. The inverse correlation between DACH1 and ATF6/PLAT is conserved in human liver. These findings reveal a regulated pathway in hepatocytes that contributes to basal circulating levels of tPA and to fibrinolysis after vascular injury.

Abstract WP133: Prevention of the Post-stroke Induction of Endogenous tPA Mitigates Brain Damage and Facilitates Neurological Recovery

Introduction: Multiple pieces of evidence suggest that the elevated endogenous tPA (endo-tPA) levels in the brain after ischemic stroke are neurotoxic and contribute to the ongoing brain damage. The neurotoxicity of endo-tPA could be due to activation of apoptotic cell signaling processes, extracellular matrix degradation, or increase in permeability of the neurovascular unit. The purpose of this study is to investigate the effect of specific endo-tPA suppression on post-stroke brain injury and neurological recovery. Methods: Male Sprague-Dawley rats were subjected to a suture model middle cerebral artery occlusion (MCAO) procedure followed by reperfusion. To achieve the specific knockdown of endo-tPA, plasmids expressing shRNAs specific to rat tPA (tPAsh) formulated as nanoparticles were administered immediately after reperfusion to rats intravenously via tail vein at a dose of 1 mg/kg body weight. Untreated, and vehicle/tPAsh-treated stroke-induced rats along with sham-operated rats were sacrificed at various post-reperfusion time points. We performed various techniques such as TTC staining, real-time PCR, and immunoblot analysis to determine both the efficiency of tPAsh plasmids and efficacy of tPAsh treatment on post-stroke brain injury. To assess the effect of tPAsh treatment on post-stroke neurological recovery, we performed modified neurological severity scores, modified adhesive removal, and beam walking tests at regular intervals until 14 days reperfusion. Results: Endo-tPA protein expression in the ischemic brain of rats was increased until 5 days reperfusion. Treatment with tPAsh formulation reduced the protein expression of tPA in the ischemic brain of rats and thereby demonstrated the in vivo efficiency of plasmids expressing tPA shRNAs. The MCAO procedure-induced mortality is comparable across the cohorts. Specific knockdown of endo-tPA reduced the infarct volume and facilitated the post-stroke neurological recovery. Conclusions: Preventing the induction of post-stroke endo-tPA levels in rat brain attenuates ischemic brain damage and improves post-stroke neurological recovery.

Deficiency of tPA Exacerbates White Matter Damage, Neuroinflammation, Glymphatic Dysfunction and Cognitive Dysfunction in Aging Mice.

Tissue plasminogen activator (tPA) is a serine protease primarily involved in mediating thrombus breakdown and regulating catabolism of amyloid-beta (Aβ). The aim of this study is to investigate age-dependent decline of endogenous tPA and the effects of tPA decline on glymphatic function and cognitive outcome in mice. Male, young (3m), adult (6m) and middle-aged (12m) C57/BL6 (wild type) and tPA knockout (tPA-/-) mice were subject to a battery of cognitive tests and white matter (WM) integrity, neuroinflammation, and glymphatic function were evaluated. Adult WT mice exhibit significantly decreased brain tPA level compared to young WT mice and middle-aged WT mice have significantly lower brain tPA levels than young and adult WT mice. Middle-aged WT mice exhibit significant neuroinflammation, reduced WM integrity and increased thrombin deposition compared to young and adult mice, and increased blood brain barrier (BBB) permeability and reduced cognitive ability compared to young WT mice. In comparison to adult WT mice, adult tPA-/- mice exhibit significant BBB leakage, decreased dendritic spine density, increased thrombin deposition, neuroinflammation, and impaired functioning of the glymphatic system. Compared to age-matched WT mice, adult and middle-aged tPA-/- mice exhibit significantly increased D-Dimer expression and decreased perivascular Aquaporin-4 expression. Compared to age-matched WT mice, young, adult and middle-aged tPA-/- mice exhibit significant cognitive impairment, axonal damage, and increased deposition of amyloid precursor protein (APP), Aβ, and fibrin. Endogenous tPA may play an important role in contributing to aging induced cognitive decline, axonal/WM damage, BBB disruption and glymphatic dysfunction in the brain.

Relation of smoking and endothelial dysfunction markers in systemic hypertension

Aim. Assessment of the markers levels of endothelial dysfunction (ED): stable metabolites of nitric oxide (NOx), endothelin-1 (E1), homocysteine (HC), von Willebrand factor (vWF) and tissue plasminogen activator (tPA) in blood plasma of smoker and nonsmoker patients with arterial hypertension (AH) of low and moderate risk, not taking antihypertension therapy regularly.Material and methods. Totally, 124 AH patients included, 45 males and 79 females, mean age 51,4±6,5 y.o., mean AH duration 7,9±7,3 y. Controls included 35 healthy volunteers (20 males, 15 females). Concentration of NOx in plasma was measured with spectrophotometry, and of vWF, HC, E1 and tPA — with immune enzyme assay.Results. To evaluate the relation of smoking and ED markers levels, AH patients and controls were selected to subgroups according to smoking status: smoker (35,5%) and non-smoker (64,5%) AH patients; smoker (38%) and non-smoker (62%) controls. In smoker AH patients comparing to non-smoking there were significantly higher concentrations of NOx — 48,2±18,8 mcM/L and 40,3±21,2 mcM/L, respectively (р&lt;0,05), E1 — 1,2±0,16 and 0,6±0,2 fM/L, resp. (р&lt;0,05), HC — 25,7±6,04 and 16,2±6,5 mcM/L, resp. (р&lt;0,05), vWF — 1,39±0,7 and 1,1±0,6 mg/dL, resp (р&lt;0,05) and tPA — 13,05±6,2 and 8,5±6,2 mcM/L, resp. (р&lt;0,05). There was correlation in the AH group, of NOx concentration and smoking (r=0,46, р&lt;0,05), and tobacco smoking duration (r=0,83, р&lt;0,05). Also, there were positive correlations of HC and smoking (r=0,4, p&lt;0,05). In control group smokers had higher HC — 20,7±5,3 and 17,2±4,7 mcM/L, resp. (р&lt;0,05), vWF — 1,3±0,8 and 0,8±0,6 mg/dL, resp. (р&lt;0,05) and tPA — 11,1±6,5 and 6,6±5,2 mcM/L, resp. (р&lt;0,05). There were no significant changes in NOx and E1.Conclusion. In smokers of both AH and control groups the levels of HC, vWF and tPA were significantly higher in comparison with nonsmokers. In smoker AH patients the mean concentrations of NOx and E1 are higher than in non-smoker patients. Levels of ED are related with not only the fact of smoking itself (р&lt;0,05), but smoking duration (р&lt;0,05).

Relationships between muscle size, strength, and physical activity in adults with muscular dystrophy.

BackgroundMuscular dystrophy (MD) is characterized by progressive muscle wasting and weakness, yet few comparisons to non‐MD controls (CTRL) of muscle strength and size in this adult population exist. Physical activity (PA) is promoted to maintain health and muscle strength within MD; however, PA reporting in adults with MD is limited to recall data, and its impact on muscle strength is seldom explored.MethodsThis study included 76 participants: 16 non‐MD (CTRL, mean age 35.4), 15 Duchenne MD (DMD, mean age 24.2), 18 Becker's MD (BMD, mean age 42.4), 13 limb‐girdle MD (LGMD, mean age 43.1), and 14 facioscapulohumeral MD (mean age 47.7). Body fat (%) and lean body mass (LBM) were measured using bioelectrical‐impedance. Gastrocnemius medialis (GM) anatomical cross‐sectional area (ACSA) was determined using B‐mode ultrasound. Isometric maximal voluntary contraction (MVC) was assessed during plantar flexion (PFMVC) and knee extension (KEMVC). PA was measured for seven continuous days using triaxial accelerometry and was expressed as daily average minutes being physically active (TPAmins) or average daily percentage of waking hours being sedentary (sedentary behaviour). Additionally, 10 m walk time was assessed.ResultsMuscular dystrophy groups had 34–46% higher body fat (%) than CTRL. DMD showed differences in LBM with 21–28% less LBM than all other groups. PFMVC and KEMVC were 36–75% and 24–92% lower, respectively, in MD groups than CTRL. GM ACSA was 47% and 39% larger in BMD and LGMD, respectively, compared with CTRL. PFMVC was associated with GM ACSA in DMD (P = 0.026, R = 0.429) and CTRL (P = 0.015, R = 0.553). MD groups were 14–38% more sedentary than CTRL groups, while DMD were more sedentary than BMD (14%), LGMD (8%), and facioscapulohumeral MD (14%). Sedentary behaviour was associated with LBM in DMD participants (P = 0.021, R = −0.446). TPAmins was associated with KEMVC (P = 0.020, R = 0.540) in BMD participants, while TPAmins was also the best predictor of 10 m walk time (P < 0.001, R 2 = 0.540) in ambulant MD, revealed by multiple linear regression.ConclusionsQuantified muscle weakness and impaired 10 m walking time is reported in adults with MD. Muscle weakness and 10 m walk time were associated with lower levels of TPA in adults with MD. Higher levels of sedentary behaviour were associated with reduced LBM in DMD. These findings suggest a need for investigations into patterns of PA behaviour, and relevant interventions to reduce sedentary behaviour and encourage PA in adults with MD regardless of impairment severity.

Pentoxifylline decreases post-operative intra-abdominal adhesion formation in an animal model.

BackgroundIntra-abdominal adhesions develop after nearly every abdominal surgery, commonly causing female infertility, chronic pelvic pain, and small bowel obstruction. Pentoxifylline (PTX) is a methylxanthine compound with immunomodulatory and antifibrotic properties. The aim of this study was to investigate whether PTX can reduce post-operative intra-abdominal adhesion formation via collagen deposition, tissue plasminogen activator (tPA) level, inflammation, angiogenesis, and fibrosis.MethodsSeventy male BALB/c mice were randomized into one of three groups: (1) sham group without peritoneal adhesion model; (2) peritoneal adhesion model (PA group); (3) peritoneal adhesion model with PTX (100 mg/kg/day i.p.) administration was started on preoperative day 2 and continued daily (PA + PTX group). On postoperative day 3 and day 7, adhesions were assessed using the Lauder scoring system. Parietal peritoneum was obtained for histological evaluation with hematoxylin and eosin (HE) and picrosirius red staining. Fibrinolysis was analyzed by tPA protein levels in the peritoneum by ELISA. Immunohistological analysis was also conducted using markers for angiogenesis (ki67+/CD31+), inflammation (F4/80+) and fibrosis (FSP-1+ and α-SMA+). All the comparisons were made by comparing the PA group with the PTX treated PA group, and p < 0.05 was considered statistically significant.ResultsIntra-abdominal adhesions were markedly reduced by PTX treatment. Compared with the PA group, PTX treatment had lower adhesion scores than the PA group on both day 3 and day 7 (p < 0.05). Histological evaluations found that PTX treatment reduced collagen deposition and adhesion thickening. ELISA analysis showed that PTX treatment significantly increased the level of tPA in the peritoneum. In addition, in the immunohistological analysis, PTX treatment was found to significantly decrease the number of ki67+/CD31+ cells at the site of adhesion. Finally, we also observed that in the PTX treated group, there was a reduction in the expression of F4/80+, FSP-1+, and α-SMA+ cells at the site of adhesion.ConclusionPTX may decrease intra-abdominal adhesion formation via increasing peritoneal fibrinolytic activity, suppressing angiogenesis, decreasing collagen synthesis, and reducing peritoneal fibrosis. Our findings suggest that PTX can be used to decrease post-operative intra-abdominal adhesion formation.

Ketamine ameliorates depressive-like behaviors by tPA-mediated conversion of proBDNF to mBDNF in the hippocampus of stressed rats

Some studies have indicated that ketamine has a rapid antidepressant effects, but the underlying molecular mechanism is still unclear. Researchers have found that mature brain-derived neurotrophic factor (mBDNF) and its precursor proBDNF are related to depression; they elicit opposite effects on cellular functions. It is clear that tissue plasminogen activator (tPA) is a key regulatory element in the conversion of proBDNF to mBDNF. The chronic unpredicted mild stress (CUMS) procedure is a classical and reliable method to establish the model of depression. This study found that sucrose preference and locomotor activity were both reduced in CUMS-treated rats while were increased in those who were injected with ketamine. The hippocampal proBDNF/mBDNF ratio was downregulated after ketamine treatment in those rats, together with an increased level of tPA in the hippocampus. However, tPA activity was unaltered after ketamine intraperitoneal injection. Intrahippocampal injection of active plasminogen activator inhibitor-1 (inhibitor of tPA) before ketamine treatment reversed the antidepressant effects and upregulated the proBDNF/mBDNF ratio. The results of this study suggest that the antidepressant action induced by ketamine may be related to tPA-mediated conversion of proBDNF to mBDNF in the hippocampus.

Fibrinolytic proteins of normal pregnancy and pre-eclamptic patients in North West Nigeria.

The hypercoagulability of pregnancy is exaggerated in pre-eclamptic state because of endothelial activation with resultant production of some endothelial derived proteins that are said to be inhibitors of fibrinolysis. This study compares these proteins like tPA, PAI-1 and D-dimers in normal pregnant women and the pre-eclamptic women. This was a comparative cross-sectional study. Eighty-five pre-eclamptic women were recruited as subjects and eighty five age, trimester and parity matched normotensive pregnant women as controls. Levels of PT, aPTT, tPA, PAI-1, D-dimer protein were determined in blood samples of subjects and controls. Urinalysis was performed with dipstick method on their urine samples. Data generated was analysed using the IBM®SPSS 20.0 (2011) soft ware packages and the level of significance was a p-value <0.05. The mean age of the respondents was 29.9±5.2 years. The median(25th-75th percentile) values of D-dimer, tPA, and PAI-1 of subjects were 730 (305.000-1560.000ng/ml), 0.11 (0.065-0,300ng/ml) and 3.65 (2.970-4,400ng/ml) respectively which were significantly higher than the corresponding values in the controls of 520 (24.000-1030.000ng/ml), 0.05 (0.040-0.090ng/ml and 2.650 (2.125-3.400ng/ml) respectively, p<0.05 each. The abnormal levels of PAI-1, D-dimer and tPA imply that they contribute to the exaggerated hypercoagulabilty state in pre-eclampsia thus, measuring their levels can help in the management of the condition.

Administration of testosterone improves the prothrombotic and antifibrinolytic parameters associated with its deficiency in an orchidectiomized rat model.

This study investigated the effect of testosterone deficiency and replacement on platelets function and aggregation, coagulation, and fibrinolysis in young adult healthy male rats. Rats were classified into three groups (n=6/group) of either "a sham-operated+vehicle," "an orchidectomized (ORX)+vehicle," and "an ORX+testosterone propionate (0.5mg/kg, 3X/week, S.C)." All treatments were carried out for 12weeks. Our results showed that ORX rats had induced platelets aggregation and coagulation and inhibited fibrinolysis. ORX-induced rats had increased ratios of adenosine diphosphate-induced aggregation, shorter bleeding time, clotting time, prothrombin time, and activated partial thromboplastin time and their sera showed increased levels of thromboxane B2 and fibrinogen levels. Concomitantly, their plasma showed increased TPA-1 and decreased tissue plasminogen activator (tPA) levels. At molecular levels, the aorta of ORX-induced rats showed increased aortic mRNA and protein levels of plasminogen activator inhibitor-1 (PAI-1), protein levels of von Willebrand Factor (vWF) and decreased mRNA and protein levels of tPA, and their liver showed increased protein levels of prothrombin and factor VII. Testosterone post-therapy to ORX-induced rats significantly reversed all these hematological and molecular changes. In conclusion, independent of any other risk factors, testosterone deficiency induces platelets aggregation and hypercoagulation and inhibits fibrinolysis, effects that can be reversed by testosterone therapy.

Plasminogen activator inhibitor-1 and tissue plasminogen activator and incident AF: Data from the PREVEND study

BackgroundTissue-type plasminogen activator (TPA) and plasminogen activator inhibitor-1 (PAI-1) have been shown to be associated with increased risk for stroke, however, the association with incident atrial fibrillation (AF) is unknown. MethodsWe examined 8265 individuals included in the PREVEND study. In all subjects, PAI-1 and TPA plasma/serum levels were measured using an ELISA kit. By means of univariate and multivariate analyses the association with incident AF was assessed. ResultsMean age was age 49 ± 13 years, and 50% were women. Of the 8265 patients free of AF at baseline, 267 (3.2%) patients developed incident AF during a mean follow-up of 9.7 ± 2.4 years. Baseline median levels of PAI-1 and TPA were 72.4 ng/ml and 3.1 ng/ml, respectively. In univariate analyses PAI-1 (Hazard ratio [HR] 1.10 95% Confidence interval [CI] 1.04–1.16, p < 0.001) and TPA (HR 1.05, 95% CI 1.01–1.08, p = 0.014) were associated with incident AF. However, after multivariate adjustment for age, sex, antihypertensive drugs, stroke, heart failure, myocardial infarction, diabetes mellitus, peripheral arterial disease, smoking, NT-proBNP, alcohol consumption, body mass index no significant association was found. ConclusionIn this community-based cohort, PAI-1 and TPA levels were not associated with incident AF.

Altered levels of brain-derived neurotrophic factor, proBDNF and tissue plasminogen activator in children with posttraumatic stress disorder

The current study aims to compare the serum brain-derived neurotrophic factor (BDNF), proBDNF and tissue plasminogen activator (tPA) levels in cases that have developed posttraumatic stress disorder (PTSD) in consequence of sexual abuse with those in healthy control subjects. Thirty-one female patients between 8 and 18 years of age who have been diagnosed with PTSD due to sexual abuse and thirty-one healthy female volunteer controls were included in the study. Frequency, intensity and severity of PTSD symptoms were assessed on the basis of Clinician-Administered Post-Traumatic Stress Disorder Scale for Children and Adolescents (CAPS-CA). Serum BDNF, proBDNF and tPA levels were measured by Enzyme-Linked Immunosorbent Assay (ELISA) method. Results of the present study revealed that serum levels of BDNF and proBDNF in PTSD group were significantly lower but tPA level was significantly higher as compared to healthy control subjects. There were no correlations between CAPS-CA scores and BDNF, proBDNF and tPA levels. Decreased levels of BDNF, as suggested to have a role in the etiopathogenesis of PTSD, appear to be a result of the reduction in proBDNF production. The increased tPA levels in such cases, on the other hand, can be a compensatory mechanism serving to increase the BDNF levels.

Lack of durable protection against cotton smoke-induced acute lung injury in sheep by nebulized single chain urokinase plasminogen activator or tissue plasminogen activator

BackgroundAirway fibrin casts are clinically important complications of severe inhalational smoke-induced acute lung injury (ISIALI) for which reliable evidence-based therapy is lacking. Nebulized anticoagulants or a tissue plasminogen activator; tPA, has been advocated, but airway bleeding is a known and lethal potential complication. We posited that nebulized delivery of single chain urokinase plasminogen activator, scuPA, is well-tolerated and improves physiologic outcomes in ISIALI. To test this hypothesis, we nebulized scuPA or tPA and delivered these agents every 4 h to sheep with cotton smoke induced ISIALI that were ventilated by either adaptive pressure ventilation/controlled mandatory ventilation (APVcmv; Group 1, n = 14) or synchronized controlled mandatory ventilation (SCMV)/limited suctioning; Group 2, n = 32). Physiologic readouts of acute lung injury included arterial blood gas analyses, PaO2/FiO2 ratios, peak and plateau airway pressures, lung resistance and static lung compliance. Lung injury was further assessed by histologic scoring. Biochemical analyses included determination of antigenic and enzymographic uPA and tPA levels, plasminogen activator and plasminogen activator inhibitor-1 activities and d-dimer in bronchoalveolar lavage (BAL). Plasma levels of uPA, tPA antigens, d-dimers and α-macroglobulin-uPA complex levels were also assessed.ResultsIn Group 1, tPA at the 2 mg dose was ineffective, but at 4 mg tPA or scuPA, the PaO2/FiO2 ratios, peak/plateau pressures improved during evolving injury (p < 0.01) without significant differences at 48 h. To improve delivery of the interventions, the experiments were repeated in Group 2 with limited suctioning/SCMV, which generally increased PAs in (BAL). In Group 2, tPA was ineffective, but scuPA (4 or 8 mg) improved physiologic outcomes (p < 0.01) and plateau pressures remained lower at 48 h. Airway bleeding occurred at 8 mg tPA. BAL plasminogen activator (PA) levels positively correlated with physiologic outcomes at 48 h.ConclusionsPhysiologic outcomes improved in sheep in which better delivery of the PAs occurred. The benefits of nebulized scuPA were achieved without airway bleeding associated with tPA, but were transient and largely abrogated at 48 h, in part attributable to the progression and severity of ISIALI.