thromboplastin and Metabolic-Syndrome

Obesity is a major cause for a spectrum of metabolic syndrome-related diseases that include insulin resistance, type 2 diabetes, and steatosis of the liver. Inflammation elicited by macrophages and other immune cells contributes to the metabolic abnormalities in obesity. In addition, coagulation activation following tissue factor (TF) upregulation in adipose tissue is frequently found in obese patients and particularly associated with diabetic complications. Genetic and pharmacological evidence indicates that TF makes significant contributions to the development of the metabolic syndrome by signaling through G protein-coupled protease activated receptors (PARs). Adipocyte TF-PAR2 signaling contributes to diet-induced obesity by decreasing metabolism and energy expenditure, whereas hematopoietic TF-PAR2 signaling is a major cause for adipose tissue inflammation, hepatic steatosis and inflammation, as well as insulin resistance. In the liver of mice on a high fat diet, PAR2 signaling increases transcripts of key regulators of gluconeogenesis, lipogenesis and inflammatory cytokines. Increased markers of hepatic gluconeogenesis correlate with decreased activation of AMP-activated protein kinase (AMPK), a known regulator of these pathways and a target for PAR2 signaling. Clinical markers of a TF-induced prothrombotic state may thus indicate a risk in obese patient for developing complications of the metabolic syndrome.

Topics: Animals; Humans; Immunologic Factors; Inflammation; Metabolic Syndrome; Models, Immunological; Obesity; Receptor, PAR-2; Signal Transduction; Thromboplastin

Clinical and epidemiological studies support a connection between obesity and thrombosis, involving elevated expression of the prothrombotic molecules plasminogen activator inhibitor-1 and tissue factor (TF) and increased platelet activation. Cardiovascular diseases and metabolic syndrome-associated disorders, including obesity, insulin resistance, type 2 diabetes, and hepatic steatosis, involve inflammation elicited by infiltration and activation of immune cells, particularly macrophages, into adipose tissue. Although TF has been clearly linked to a procoagulant state in obesity, emerging genetic and pharmacologic evidence indicate that TF signaling via G protein-coupled protease-activated receptors (PAR2, PAR1) additionally drives multiple aspects of the metabolic syndrome. TF-PAR2 signaling in adipocytes contributes to diet-induced obesity by decreasing metabolism and energy expenditure, whereas TF-PAR2 signaling in hematopoietic and myeloid cells drives adipose tissue inflammation, hepatic steatosis, and insulin resistance. TF-initiated coagulation leading to thrombin-PAR1 signaling also contributes to diet-induced hepatic steatosis and inflammation in certain models. Thus, in obese patients, clinical markers of a prothrombotic state may indicate a risk for the development of complications of the metabolic syndrome. Furthermore, TF-induced signaling could provide new therapeutic targets for drug development at the intersection between obesity, inflammation, and thrombosis.

Topics: Adipocytes; Adipose Tissue; Animals; Cardiovascular Diseases; Gene Expression Regulation; Humans; Inflammation; Insulin Resistance; Macrophages; Metabolic Syndrome; Mice; Mice, Obese; Models, Biological; Obesity; Plasminogen Activator Inhibitor 1; Receptor, PAR-1; Receptor, PAR-2; Risk Factors; Signal Transduction; T-Lymphocytes, Regulatory; Thrombophilia; Thromboplastin; Thrombosis

Metabolic syndrome (MS) represents a cluster of cardiovascular risk factors and an increased risk of cardiovascular events. The carotid intima-media thickness (CIMT) is correlated with coronary and carotid atherosclerosis, and is a significant predictor of cardiovascular events. Tissue factor (TF) is an initiator of the extrinsic coagulation cascade and is expressed on peripheral blood monocytes and macrophages in atherosclerotic plaques. TF plays important roles in both thrombosis and atherosclerosis. No study has investigated the relationship between monocyte TF activity and CIMT in MS patients.. Peripheral blood mononuclear cells (PBMCs) were collected from 39 normal subjects and 110 patients with MS. The procoagulant activity (PCA) in monocytes was measured using a one-stage clotting assay and is expressed as the mean±SD (mU TF/10(6) PBMCs).. The PCA in monocytes in MS patients was significantly higher than in normal subjects (86.2 ±69.5 vs. 52.4±9.9 mU TF/10(6) PBMCs, p < 0.001). In multivariate analysis, patient age (β coefficient= 0.373, p < 0.001), high-density lipoprotein cholesterol (β coefficient=-0.307, p = 0.001) and PCA (β coefficient= 0.422, p =0.002) were each significantly and independently associated with CIMT.. These data indicate that the upregulation of monocyte TF activity is significantly associated with CIMT in MS patients.

Topics: Aged; Cardiovascular Diseases; Carotid Arteries; Case-Control Studies; Female; Humans; Male; Metabolic Syndrome; Monocytes; Thromboplastin; Tunica Intima; Up-Regulation

Type 2 diabetes is associated with accelerated atherosclerosis. Because cell-derived microparticles support coagulation and inflammation, they may be involved in atherogenesis. We characterized circulating microparticles both in patients with uncomplicated, well-regulated type 2 diabetes and in healthy subjects, as well as their relationship with coagulation and metabolic control.. Microparticles were isolated from plasma, stained with annexin V, cell-specific monoclonal antibodies (MoAbs) and a MoAb directed against tissue factor (TF), and analyzed by flow cytometry. Microparticle numbers and origin were comparable in the two groups, but the median number of TF-positive microparticles was twice as high in patients than in controls (P=0.018). Patients had higher percentages of TF-positive microparticles from T-helper cells (P=0.045), granulocytes (P=0.004), and platelets (P=0.002). Subpopulations of TF-positive microparticles from platelets and T-helper cells exposed granulocytic markers. Correlations were found between the numbers of various TF-positive microparticle subpopulations and body mass index, fasting plasma glucose and insulin, or tumor necrosis factor-alpha and serum HDL cholesterol. Microparticles from patients generated less thrombin in vitro (P=0.007). Microparticle numbers did not correlate with in vivo coagulation markers prothrombin fragment F(1+2) and thrombin-antithrombin complexes.. TF, possibly of granulocytic origin, is exposed on microparticle subpopulations in asymptomatic patients with well-regulated type 2 diabetes. TF-positive microparticles are associated with components of the metabolic syndrome but not with coagulation. Thus, TF on microparticles may be involved in processes other than coagulation, including transcellular signaling or angiogenesis.

Topics: Adult; Aged; Antigens, Surface; Biomarkers; Blood Platelets; Body Mass Index; Cell Membrane Structures; Cholesterol, HDL; Diabetes Mellitus, Type 2; Female; Granulocytes; Humans; Macromolecular Substances; Male; Metabolic Syndrome; Middle Aged; Reference Values; T-Lymphocytes; Thrombin; Thromboplastin; Tumor Necrosis Factor-alpha

Smoking increases the risk of atherothrombotic events. Tissue factor (TF) mainly expressed on monocytes plays an important role in thrombosis and atherosclerosis. Metabolic syndrome (MetS) is being increasingly recognized as a major atherothrombotic risk factor, but the effects of smoking on monocyte TF activity (MTFA), carotid atherosclerosis estimated on carotid intima-media thickness (CIMT), and long-term prognosis in MetS remain unclear.Methods and Results:A total of 301 MetS patients lacking any known cardiovascular disease were prospectively investigated and classified into 4 groups according to smoking status at entry and at 12 months as follows: never smokers, past smokers, quitters, and persistent smokers. Peripheral blood mononuclear cells (PBMC) were isolated, and MTFA was measured using a coagulation assay. Linear trends for higher baseline MTFA and CIMT were observed among persistent smokers, quitters, and past smokers compared with never smokers. At 12 months, MTFA and CIMT decreased in never and past smokers and quitters but increased in persistent smokers. Six acute myocardial infarctions and 8 strokes occurred during a median follow-up of 66.0 months. Persistent smoking was associated with an increased risk of events (P<0.001).. Smoking is associated with upregulated MTFA and progression of CIMT, which may be related to the risk of atherothrombotic events in MetS patients.

Topics: Aged; Carotid Artery Diseases; Female; Humans; Male; Metabolic Syndrome; Middle Aged; Monocytes; Myocardial Infarction; Prognosis; Smoking; Stroke; Thromboplastin

Topics: Carotid Artery Diseases; Humans; Metabolic Syndrome; Monocytes; Prognosis; Smoking; Thromboplastin; Vascular Endothelial Growth Factor A

The metabolic syndrome (MetS) has been found to be closely related with thrombotic diseases. The mechanism, however, is far from elucidated.. This study was designed to investigate the relationship between endogenous resistin and thrombosis mediating factors, as well as its potential effects on the gene expression of cardiovascular disease biomarkers.. Ninety patients satisfied the MetS criteria, and 55 healthy subjects were recruited as part of a single-center clinical study. Plasma levels of resistin, tissue factor (TF), tissue factor pathway inhibitor (TFPI), tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1) were measured by enzymelinked immunosorbent assays. The effect of resistin on the expression of cardiovascular disease biomarkers in human umbilical vein endothelial cells (HUVEC) was assayed by gene microarray.. 1) The average levels of resistin in MetS patients with or without acute myocardial or cerebral infarction were significantly higher than those of the controls. 2) The TF and TFPI increase was higher in MetS with infarction patients than in MetS patients. 3) In MetS with infarction patients, resistin was positively correlated with TF and PAI-1 (r=0.313, p=0.008; r=0.401, p=0.002, respectively). 4) In HUVEC, the microarray showed that apolipoprotein C-I, ACE, tumor necrosis factor receptor superfamily member 1A (TNFRSF1A) and member 5 (CD40) genes expression were dramatically increased by resistin.. In patients with MetS, resistin is strongly associated with hypercoagulative and hypofibrinolitic activities. Moreover, resistin may induce thrombotic complications via mediating the lipoprotein metabolism and stimulating inflammation.

Topics: Aged; Asian People; Biomarkers; Cardiovascular Diseases; Cells, Cultured; Endothelial Cells; Female; Humans; Lipoproteins; Male; Metabolic Syndrome; Microarray Analysis; Middle Aged; Plasminogen Activator Inhibitor 1; Resistin; Thromboplastin; Thrombosis; Tissue Plasminogen Activator

The metabolic syndrome (MetS) is a cluster of cardiovascular risk factors closely linked to inflammation and insulin resistance (IR). Tissue factor (TF) is an initiator of the extrinsic coagulation cascade and is expressed on peripheral blood monocytes and macrophages in atherosclerotic plaques. Monocytes are the principle cells capable of TF synthesis. Therefore, TF plays an important role in both thrombosis and atherosclerosis. Elevated levels of lipopolysaccharide (LPS), a strong stimulator of TF, have been observed in patients with MetS. No study has investigated the relationship between monocyte TF activity and inflammation, and IR in MetS.. Peripheral blood mononuclear cells (PBMCs) were collected from 40 normal subjects and 77 patients with MetS. Mononuclear cell TF procoagulant activity (MPCA) was measured with and without 100 pg/ml LPS stimulation using a 1-stage clotting assay and expressed as the mean +/- SD (mU TF/10(6) PBMCs). MPCA in MetS was significantly greater than in normal subjects (without LPS: 88.0+/-74.8 vs 52.6+/-9.8 mU TF/10(6) PBMCs, P<0.001; with LPS: 269.6+/-165.6 vs 158.6+/-42.8 mU TF/10(6) PBMCs, P<0.001). The LPS-stimulated log MPCA in MetS patients was significantly associated with homeostasis model assessment of IR (r=0.256, P=0.024) and log high-sensitivity C-reactive protein (r=0.332, P=0.003).. Upregulation of monocyte TF is significantly associated with low-grade inflammation and IR in MetS.

Topics: Aged; C-Reactive Protein; Chronic Disease; Disease Progression; Female; Homeostasis; Humans; In Vitro Techniques; Inflammation; Insulin Resistance; Lipopolysaccharides; Male; Metabolic Syndrome; Middle Aged; Monocytes; Risk Factors; Thromboplastin; Up-Regulation