The effect of hyperthyroidism on procoagulant, anticoagulant and fibrinolytic factors

2012 ◽  
Vol 108 (12) ◽  
pp. 1077-1088 ◽  
Author(s):  
Bregje van Zaane ◽  
Erica Romualdi ◽  
Dees Brandjes ◽  
Victor Gerdes ◽  
Alessandro Squizzato ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Meta Analysis ◽  
Experimental Studies ◽  
Plasminogen Activator Inhibitor ◽  
Plasminogen Activator Inhibitor 1 ◽  
Cross Sectional ◽  
Before And After ◽  
Fibrinolytic Parameters ◽  
Overt Hyperthyroidism

SummarySeveral coagulation and fibrinolytic parameters appear to be affected by thyroid hormone excess;however, the net effect on the haemostatic system remains unclear. We aimed to update our previous review and systematically summarise and meta-analyse the data by assessing the effects of thyrotoxicosis on the coagulation and fibrinolytic system in vivo. Data sources included MEDLINE (2006–2012), EMBASE (2006–2012), and reference lists. The sources were combined with our previous search containing studies from 1980–2006. Eligible studies were all observational or experimental studies. Two investigators independently extracted data and rated study quality. Weighted mean proportion and 95% confidence intervals were calculated and pooled using a fixed and a random-effects model. A total of 29 articles consisting of 51 studies were included, as in several articles more than one study was described. We included four intervention (before and after treatment in hyperthyroid patients), five cross-sectional (hyperthyroid subjects and euthyroid controls), and four experimental (before and after use of thyroid hormone in euthyroid subjects) medium/high quality studies for meta-analysis. We found that thyrotoxicosis shifts the haemostatic balance towards a hypercoagulable and hypofibrinolytic state with a rise in factors VIII and IX, fibrinogen, von Willebrand factor, and plasminogen activator inhibitor-1. This was observed in endogenous and exogenous thyrotoxicosis, and in subclinical as well as overt hyperthyroidism. We conclude that both subclinical and overt hyperthyroidism induce a prothrombotic state, which is therefore likely to be a risk factor for venous thrombosis.

Anti-thrombotic Effect of a PAI-1 Inhibitor in Rats Given Endotoxin

1996 ◽  
Vol 75 (01) ◽  
pp. 118-126 ◽  
Author(s):  
T Abrahamsson ◽  
V Nerme ◽  
M Strömqvist ◽  
B Åkerblom ◽  
A Legnehed ◽  
...  
Keyword(s):  
Plasminogen Activator Inhibitor ◽  
Rat Plasma ◽  
Clot Lysis ◽  
Fibrin Deposition ◽  
Plasminogen Activator Inhibitor 1 ◽  
Fab Fragment ◽  
Dose Dependent Decrease ◽  
Pai 1

SummaryThe aim of this study was to investigate the anti-thrombotic effects of an inhibitor of the plasminogen activator inhibitor-1 (PAI-1) in rats given endotoxin. In studies in vitro, PRAP-1, a Fab-fragment of a polyclonal antibody against human PAI-1, was shown to inhibit PAI-1 activity in rat plasma as well as to stimulate clot-lysis of the euglobulin fraction derived from rat plasma. Endotoxin administered to anaesthetised rats produced a marked increase in plasma PAI-1 activity. To study fibrin formation and lysis in vivo after intravenous (i. v.) injection of the coagulant enzyme batroxobin, 125I-fibrinogen was administered to the animals. The thrombi formed by batroxobin were rapidly lysed in control animals, while the rate of lysis was markedly attenuated in rats given endotoxin. PRAP-1 was administered i.v. (bolus + infusion) to rats given endotoxin and batroxobin and the PAI-1 inhibitor caused a dose-dependent decrease in the 125I-fibrin deposition in the lungs. An immunohistochemical technique was used to confirm this decrease in density of fibrin clots in the tissue. Furthermore, PRAP-1 decreased plasma PAI-1 activity in the rats and this reduction was correlated to the decrease in lung 125I-fibrin deposition at the corresponding time point. It is concluded that in this experimental model the PAI-1 antibody PRAP-1 may indeed inhibit thrombosis in animals exposed to endotoxin.

The Roles of α2-Antiplasmin and Plasminogen Activator Inhibitor 1 (PAI-1) in the Inhibition of Clot Lysis

1993 ◽  
Vol 70 (02) ◽  
pp. 301-306 ◽  
Author(s):  
Linda A Robbie ◽  
Nuala A Booth ◽  
Alison M Croll ◽  
Bruce Bennett
Keyword(s):  
Plasminogen Activator ◽  
Plasminogen Activator Inhibitor ◽  
Fibrin Clot ◽  
Clot Lysis ◽  
Plasminogen Activator Inhibitor 1 ◽  
Dependent Inhibition ◽  
Activator Inhibitor ◽  
Pai 1

SummaryThe relative importance of the two major inhibitors of fibrinolysis, α2-antiplasmin (α2-AP) and plasminogen activator inhibitor (PAI-1), were investigated using a simple microtitre plate system to study fibrin clot lysis in vitro. Cross-linked fibrin clots contained plasminogen and tissue plasminogen activator (t-PA) at concentrations close to physiological. Purified α2-AP and PAI-1 caused dose-dependent inhibition. All the inhibition due to normal plasma, either platelet-rich or poor, was neutralised only by antibodies to α2-AP. Isolated platelets, at a final concentration similar to that in blood, 2.5 × 108/ml, markedly inhibited clot lysis. This inhibition was neutralised only by antibodies to PAI-1. At the normal circulating ratio of plasma to platelets, α2-AP was the dominant inhibitor. When the platelet:plasma ratio was raised some 20-fold, platelet PAI-1 provided a significant contribution. High local concentrations of PAI-1 do occur in thrombi in vivo, indicating a role for PAI-1, complementary to that of α2-AP, in such situations.

scholarly journals Structural Insight into the Two-Step Mechanism of PAI-1 Inhibition by Small Molecule TM5484

2021 ◽  
Vol 22 (3) ◽  
pp. 1482 ◽  
Author(s):  
Machteld Sillen ◽  
Toshio Miyata ◽  
Douglas E. Vaughan ◽  
Sergei V. Strelkov ◽  
Paul J. Declerck
Keyword(s):  
Binding Site ◽  
Small Molecule ◽  
Intracellular Signaling ◽  
Plasminogen Activator Inhibitor ◽  
Plasminogen Activator Inhibitor 1 ◽  
Joint Region ◽  
Flexible Joint ◽  
Step Mechanism ◽  
Pai 1

Plasminogen activator inhibitor-1 (PAI-1), a key regulator of the fibrinolytic system, is the main physiological inhibitor of plasminogen activators. By interacting with matrix components, including vitronectin (Vn), PAI-1 plays a regulatory role in tissue remodeling, cell migration, and intracellular signaling. Emerging evidence points to a role for PAI-1 in various pathological conditions, including cardiovascular diseases, cancer, and fibrosis. Targeting PAI-1 is therefore a promising therapeutic strategy in PAI-1-related pathologies. A class of small molecule inhibitors including TM5441 and TM5484, designed to bind the cleft in the central β-sheet A of PAI-1, showed to be potent PAI-1 inhibitors in vivo. However, their binding site has not yet been confirmed. Here, we report two X-ray crystallographic structures of PAI-1 in complex with TM5484. The structures revealed a binding site at the flexible joint region, which is distinct from the presumed binding site. Based on the structural analysis and biochemical data we propose a mechanism for the observed dose-dependent two-step mechanism of PAI-1 inhibition. By binding to the flexible joint region in PAI-1, TM5484 might restrict the structural flexibility of this region, thereby inducing a substrate form of PAI-1 followed by a conversion to an inert form.

Elevated levels of activin A in clinical and experimental pulmonary hypertension

2009 ◽  
Vol 106 (4) ◽  
pp. 1356-1364 ◽  
Author(s):  
Arne Yndestad ◽  
Karl-Otto Larsen ◽  
Erik Øie ◽  
Thor Ueland ◽  
Camilla Smith ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Transforming Growth Factor ◽  
Experimental Studies ◽  
Plasminogen Activator Inhibitor ◽  
Muscle Cells ◽  
Activin A ◽  
Plasminogen Activator Inhibitor 1 ◽  
And Control

Activin A, a member of the transforming growth factor (TGF)-β superfamily, is involved in regulation of tissue remodeling and inflammation. Herein, we wanted to explore a role for activin A in pulmonary hypertension (PH). Circulating levels of activin A and its binding protein follistatin were measured in patients with PH ( n = 47) and control subjects ( n = 14). To investigate synthesis and localization of pulmonary activin A, we utilized an experimental model of hypoxia-induced PH. In mouse lungs, we also explored signaling pathways that can be activated by activin A, such as phosphorylation of Smads, which are mediators of TGF-β signaling. Possible pathophysiological mechanisms initiated by activin A were explored by exposing pulmonary arterial smooth muscle cells in culture to this cytokine. Elevated levels of activin A and follistatin were found in patients with PH, and activin A levels were significantly related to mortality. Immunohistochemistry of lung autopsies from PH patients and lungs with experimental PH localized activin A primarily to alveolar macrophages and bronchial epithelial cells. Mice with PH exhibited increased pulmonary levels of mRNA for activin A and follistatin in the lungs, and also elevated pulmonary levels of phosphorylated Smad2. Finally, we found that activin A increased proliferation and induced gene expression of endothelin-1 and plasminogen activator inhibitor-1 in pulmonary artery smooth muscle cells, mediators that could contribute to vascular remodeling. Our findings in both clinical and experimental studies suggest a role for activin A in the development of various types of PH.

The Effect of Plantago major on Wound Healing in Preclinical Studies: A Systematic Review

2021 ◽  
Vol 67 (1) ◽  
pp. 27-34
Author(s):  
Fernanda Cardoso ◽  
Jéssica Breder ◽  
Priscila Apolinário ◽  
Henrique Oliveia ◽  
Maria Saidel ◽  
...  
Keyword(s):  
Systematic Review ◽  
Wound Healing ◽  
Meta Analysis ◽  
Experimental Studies ◽  
Risk Of Bias ◽  
Preclinical Studies ◽  
Plantago Major ◽  
Best Response ◽  
Meta Analyses

BACKGROUND: Plantago major is a medicinal plant that has been used for centuries to treat various health conditions including wounds. PURPOSE: To investigate the effectiveness of the topical use of P major in healing skin wounds in animal models. METHODS: Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic review was conducted. Seven (7) electronic databases (Virtual Health Library, Public/Publisher MEDLINE, Scopus, Web of Science, Embase, Cumulative Index of Nursing and Allied Health Literature, and CAB Direct) were searched for controlled studies published in English from January 2006 to March 2020. The Collaborative Approach to Meta Analysis and Review of Animal Data from Experimental Studies tools guided the evaluation of the studies and determined their quality. The Systematic Review Center for Laboratory Animal Experimentation was used to assess the risk of bias. RESULTS: Of the 176 publications identified, 4 met the inclusion criteria. Studies included 20 to 100 animals and varying concentrations of P major. There were no reports of losses during research. Wound healing was assessed between 17 and 21 days following wounding. The best response in terms of wound contraction rate occurred with 10%, 20%, and 50% concentrations when compared with control groups. One (1) study did not have an animal ethics committee review. All studies had a high risk of bias and a lack of methodological rigor. CONCLUSION: The results of this review did not find evidence about the in vivo effectiveness of P major for wound healing. More rigorous preclinical studies with adequate sample sizes are required to identify the best concentrations and formulations as well as increase understanding about the mechanisms of action of P major in wound healing.

Mesenchymal Stem Cell Therapy for Acetaminophen-Related Liver Injury: A Systematic Review and Meta-Analysis of Experimental Studies in Vivo

2021 ◽  
Vol 16 ◽  
Author(s):  
Li Wang ◽  
Yiwen Zhang ◽  
Jiajun Zhong ◽  
Yuan Zhang ◽  
Shuisheng Zhou ◽  
...  
Keyword(s):  
Systematic Review ◽  
Stem Cell ◽  
Liver Injury ◽  
Mesenchymal Stem Cell ◽  
Small Sample Size ◽  
Meta Analysis ◽  
Experimental Studies ◽  
Small Sample ◽  
Control Group

Objective: The efficacy of mesenchymal stem cell (MSC) therapy in acetaminophen-induced liver injury has been investigated in animal experiments, but individual studies with a small sample size cannot be used to draw a clear conclusion. Therefore, we conducted a systematic review and meta-analysis of preclinical studies to explore the potential of using MSCs in acetaminophen-induced liver injury. Methods: Eight databases were searched for studies reporting the effects of MSCs on acetaminophen hepatoxicity. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were used. SYRCLE’s risk of bias tool for animal studies was applied to assess the methodological quality. A meta-analysis was performed by using RevMan 5.4 and STATA/SE 16.0 software. Results: Eleven studies involving 159 animals were included according to PRISMA statement guidelines. Significant associations were found for MSCs with the levels of alanine transaminase (ALT) (standardized mean difference (SMD) − 2.58, p < 0.0001), aspartate aminotransferase (AST) (SMD − 1.75, p = 0.001), glutathione (GSH) (SMD 3.7, p < 0.0001), superoxide dismutase (SOD) (SMD 1.86, p = 0.022), interleukin 10 (IL-10) (SMD 5.14, p = 0.0002) and tumor necrosis factor-α (TNF-α) (SMD − 4.48, p = 0.011) compared with those in the control group. The subgroup analysis showed that the tissue source of MSCs significantly affected the therapeutic efficacy (p < 0.05). Conclusion: Our meta-analysis results demonstrate that MSCs could be a potential treatment for acetaminophen-related liver injury.

scholarly journals Water-Pipe Smoke Exposure-Induced Circulatory Disturbances in Mice, and the Influence of Betaine Supplementation Thereon

2017 ◽  
Vol 41 (3) ◽  
pp. 1098-1112 ◽  
Author(s):  
Abderrahim Nemmar ◽  
Suhail Al-Salam ◽  
Sumaya Beegam ◽  
Priya Yuvaraju ◽  
Abderrahim Oulhaj ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Plasma Concentrations ◽  
Immunohistochemical Analysis ◽  
Plasminogen Activator Inhibitor ◽  
Water Pipe ◽  
Plasminogen Activator Inhibitor 1 ◽  
Factor Α ◽  
Air Control

Background/Aims: It has been shown, both experimentally and clinically, that water-pipe smoke (WPS) exposure adversely affects the cardiovascular system (CVS) through the generation of oxidative stress and inflammation. Betaine, a naturally occurring compound in common foods, has antioxidant and anti-inflammatory actions. However, its potential to mitigate the adverse effect of WPS on the CVS has never been reported before. This is the subject of this study in mice. Methods: Mice were exposed daily for 30 min to either normal air (control), or to WPS for two consecutive weeks. Betaine was administered daily by gavage at a dose of 10mg/kg, 1h before either air or WPS exposure. Results: Betaine mitigated the in vivo prothrombotic effect of WPS in pial arterioles and venules. Moreover, it reversed the WPS-induced decrease in circulating platelets. Likewise, betaine alleviated platelet aggregation in vitro, and the shortening of activated partial thromboplastin time and prothrombin time induced by WPS. Betaine reduced the increase of plasminogen activator inhibitor-1 and fibrinogen concentrations in plasma induced by WPS. Betaine also diminished the WPS-induced increase of plasma concentrations of interleukin 6 and tumor necrosis factor α, and attenuated the increase of lipid peroxidation and superoxide dismutase. Immunohistochemical analysis of the heart revealed an increase in the expression of inducible nitric oxide synthase and cytochrome C by cardiomyocytes of the WPS-exposed mice. These effects were averted by betaine. Conclusion: Our findings suggest that betaine treatment significantly mitigated WPS-induced hypercoagulability, and inflammation, as well as systemic and cardiac oxidative stress.

In Vivo Stimulation of Vascular Plasminogen Activator Inhibitor-1 Production by very Low-Density Lipoprotein Involves Transcription Factor Binding to a VLDL-Responsive Element

2000 ◽  
Vol 84 (10) ◽  
pp. 706-711 ◽  
Author(s):  
Mikko Ares ◽  
Maria Stollenwerk ◽  
Cecilia Giachelli ◽  
Marta Scatena ◽  
Anders Hamsten ◽  
...  
Keyword(s):  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Plasminogen Activator Inhibitor ◽  
High Plasma ◽  
Plasminogen Activator Inhibitor 1 ◽  
Mrna And Protein Expression ◽  
Responsive Element ◽  
Activator Inhibitor ◽  
Pai 1

SummaryHigh plasma levels of plasminogen activator inhibitor-1 (PAI-1) are associated with an increased risk of cardiovascular disease. There is also a close relation between high plasma levels of PAI-1 and hypertriglyceridemia. Cell culture studies have shown that very low density lipoprotein (VLDL) increases the production and secretion of PAI-1 in endothelial cells and hepatocytes, suggesting a possible mechanism for this association. To determine whether VLDL stimulates PAI-1 production in vascular cells also in vivo, Sprague-Dawley rats were injected intravenously with 6 mg/kg of VLDL (derived from human subjects with type IV hyperlipidemia). Previous studies have demonstrated that this results in an accumulation of human VLDL in the aorta and other arteries followed by increased nuclear factor-kappa B (NF-κB) activation. Endothelial, but not smooth muscle cells, showed a basal PAI-1 mRNA and protein expression as assessed by in situ hybridization and immunohistochemistry, respectively. Six to twenty-four hours after the VLDL injection, lipoprotein particle accumulation was seen in the aortic wall, which was accompanied by increasing PAI-1 mRNA and protein expression in endothelial and smooth muscle cells. Within the rat PAI-1 promoter we identified a sequence located at −589 to −571 with 74% homology with the recently described VLDL responsive element in the human PAI-1 promoter and located adjacent to a 4-guanosine motif presumably corresponding to the human 4G/5G polymorphism. Transient transfection studies showed that VLDL exerts its stimulatory effects on rat PAI-1 gene expression in vascular cells by interaction with promoter sequences located within bp −656 and −505. Electrophoretic mobility shift assays showed that VLDL increases the binding of as yet incompletely characterized factors to this response element. Taken together these observations support a direct influence of VLDL on vascular PAI-1 gene expression in vivo. This stimulation is exerted on the level of PAI-1 gene transcription, and involves transcription factor binding to a VLDL responsive element adjacent to a 4G motif within the PAI-1 promoter.

Effect of Honey and Green Tea Solutions on Streptococcus mutans

2015 ◽  
Vol 39 (5) ◽  
pp. 435-441
Author(s):  
F Abdelmegid ◽  
M Al-Agamy ◽  
A Alwohaibi ◽  
H Ka'abi ◽  
F Salama
Keyword(s):  
Streptococcus Mutans ◽  
Green Tea ◽  
Saliva Sample ◽  
Post Intervention ◽  
Cross Sectional ◽  
Colony Forming Unit ◽  
Before And After ◽  
The Mean ◽  
Mouth Rinsing

Objectives: The aim of this cross-sectional in vivo study was to assess the effect of green tea and honey solutions on the level of salivary Streptococcus mutans. Study design: A convenient sample of 30 Saudi boys aged 7–10 years were randomly assigned into 2 groups of 15 each. Saliva sample was collected for analysis of level of S. mutans before rinsing. Commercial honey and green tea were prepared for use and each child was asked to rinse for two minutes using 10 mL of the prepared honey or green tea solutions according to their group. Saliva samples were collected again after rinsing. The collected saliva samples were prepared and colony forming unit (CFU) of S. mutans per mL of saliva was calculated. Results: The mean number of S. mutans before and after rinsing with honey and green tea solutions were 2.28* 108(2.622*108), 5.64 *107(1.03*108), 1.17*109(2.012*109) and 2.59*108 (3.668*108) respectively. A statistically significant reduction in the average number of S. mutans at baseline and post intervention in the children who were assigned to the honey (P=0.001) and green tea (P=0.001) groups was found. Conclusions: A single time mouth rinsing with honey and green tea solutions for two minutes effectively reduced the number of salivary S. mutans of 7–10 years old boys.

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