fibrinopeptide-a and Diabetes-Mellitus--Type-1

Specific thromboxane synthetase inhibition is associated with a significant fall in abnormal albumin excretion rate in insulin-dependent diabetics (IDDs). This may be due to an effect on haemostasis or changes in renal blood flow. We have studied the effect of a specific thromboxane synthetase inhibitor, UK-38,485, on coagulation parameters in 15 IDDs, at -8, 0, 8 and 16 weeks after double blind administration of drug or placebo. Serum thromboxane B2 fell in the drug group (695 +/- 205 vs 134 +/- 180 pg/ml, n = 7, p less than 0.001), but not in the placebo group (713 +/- 409 vs 614 +/- 178 pg/ml, n = 8). The drug group showed significant reduction in adrenaline primary maximum (24 +/- 7 vs 37 +/- 7%, p less than 0.05) and ADP maximum (71 +/- 14 vs 81 +/- 7%, p less than 0.05) aggregation not seen in the placebo group. Dilute whole blood clot lysis time was, however, increased in the drug group (7.1 +/- 1.6 vs 6.25 +/- 2.4 hr, p less than 0.05) and no effect was observed in either group on in vivo parameters of platelet aggregation (beta-thromboglobulin, platelet factor 4 and platelet micro-aggregates). We conclude that specific thromboxane synthetase inhibition is probably not associated with an overall improvement in haemostasis and the clinical effects observed cannot be explained on this basis.

Topics: beta-Thromboglobulin; Diabetes Mellitus, Type 1; Fibrinopeptide A; Glycated Hemoglobin; Hemostasis; Humans; Imidazoles; Platelet Aggregation; Platelet Factor 4; Thromboxane-A Synthase

Type 1 diabetes (insulin-dependent diabetes mellitus, IDDM) is an autoimmune disease affecting about 0.12% of the world's population. Diabetic nephropathy (DN) is a major long-term complication of both types of diabetes and retains a high human, social and economic cost. Thus, the identification of markers for the early detection of DN represents a relevant target of diabetic research. The present work is a pilot study focused on proteomic analysis of serum of controls (n=9), IDDM patients (n=10) and DN patients (n=4) by the ClinProt profiling technology based on mass spectrometry. This approach allowed to identify a pattern of peptides able to differentiate the studied populations with sensitivity and specificity close to 100%. Variance of the results allowed to estimate the sample size needed to keep the expected False Discovery Rate low. Moreover, three peptides differentially expressed in the serum of patients as compared to controls were identified by LC-ESI MS/MS as the whole fibrinopeptide A peptide and two of its fragments, respectively. The two fragments were under-expressed in diabetic patients, while Fibrinopeptide A was over-expressed, suggesting that anomalous turnover of Fibrinopeptide A could be involved in the pathogenesis of DN.

Topics: Adult; Area Under Curve; Blood Pressure; Case-Control Studies; Chromatography, Liquid; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Fibrinopeptide A; Humans; Male; Metabolome; Middle Aged; Peptide Fragments; Pilot Projects; Proteome; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry

The biological activity of thrombin and coagulation factor Xa was assessed in 62 insulin-dependent diabetic patients. A group of non-diabetic subjects of comparable age and urinary albumin excretion rate (< 30 mg/24 h) served as control subjects (group 1, n = 14). The patients were divided into three groups according to urinary albumin excretion rate. In group 2, albumin excretion rate was less than 30 mg/24 h (n = 17), in group 3 albumin excretion rate was in the range 30-300 mg/24 h (n = 20) and in group 4 albumin excretion rate was greater than 300 mg/24 h (n = 25). Compared to non-diabetic control subjects an increase in the biological activity of factor Xa was observed in all groups of diabetic patients (prothrombin fragment 1 + 2 levels were 1.14 +/- 0.38 nmol/l in group 2, p < 0.005; 1.06 +/- 0.45 nmol/l in group 3, p < 0.05 and 1.03 +/- 0.31 nmol/l in group 4, p < 0.05 vs 0.75 +/- 0.34 nmol/l in group 1). No difference in the level of antithrombin III was seen between the groups. We reconfirmed the presence of intimal dysfunction in diabetic nephropathy demonstrated by elevated transcapillary escape rate of albumin in group 4 compared with group 2 (8.9 +/- 2.0% vs 7.0 +/- 1.9%, p < 0.05). An overall positive correlation between transcapillary escape rate and prothrombin fragment 1 + 2 was found (r = 0.36, p < 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Albuminuria; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Factor Xa; Female; Fibrinopeptide A; Humans; Male; Middle Aged; Peptide Fragments; Prothrombin; Thrombin; Tunica Intima

To examine the relationship between diabetic vascular disease and haemostasis, a set of sensitive assays has been used to assess in vivo activation of coagulation in 62 diabetic patients (41 Type 1 and 21 Type 2), aged 19-68 years, who had been screened for the presence of complications. Fibrinopeptide A, an index of thrombin activity, was significantly increased in diabetic patients compared with control subjects (p less than 0.05), in both plasma (with complications mean 8.04 +/- 11.87 (+/- SD); without complications 7.21 +/- 10.13; control subjects 2.11 +/- 1.40 micrograms l-1) and urine (with complications mean 1.48 +/- 0.74; without complications 1.35 +/- 0.62; control subjects 0.98 +/- 0.39 micrograms l-1). Activated factor VII (VIIa ratio 1.21 +/- 0.39; 1.13 +/- 0.23; 1.01 +/- 0.11) and fibrinogen (3.15 +/- 0.59; 3.11 +/- 0.69; 2.70 +/- 0.57 g l-1) were also elevated in diabetic patients with and without complications (VIIa p less than 0.05, fibrinogen p less than 0.01). The only difference between Type 1 and Type 2 patients was in fibrin degradation products (Type 1 0.28 +/- 0.18; Type 2 0.40 +/- 0.18 mg l-1, p less than 0.01). Plasma levels of fibrin degradation products were elevated in diabetic patients (p less than 0.05 vs control subjects), and correlated with age (r = 0.44, p less than 0.01) but were unrelated to the presence of complications. There were no significant differences in any coagulation variables between diabetic patients with and without complications.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Blood Coagulation; Blood Glucose; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Factor VII; Factor VIIa; Female; Fibrin Fibrinogen Degradation Products; Fibrinogen; Fibrinopeptide A; Glycated Hemoglobin; Hemostasis; Humans; Male; Middle Aged; Smoking

Diabetic patients are prone to develop vascular complications. Increased procoagulatory factors and a reduced fibrinolytic potential are considered as thrombogenic risk factors, although controversy remains. In epidemiological and dietary intervention studies fish or fish oil, rich in the two n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have demonstrated a potential to reduce cardiovascular disease. We compared the plasmatic coagulatory and fibrinolytic profile of 13 near normoglycaemic type I diabetics almost free of cardiovascular disease with healthy volunteers, matched for age and sex. Except for fibrinogen levels and tPA activity being elevated and soluble fibrin and fibrinopeptide A being reduced, no differences could be discerned between type I diabetics and controls in all investigated plasmatic parameters. In a dietary intervention study we investigated the effects of 5.4 g EPA and 2.7 g DHA per day during and after a 4-week dietary supplementation in the diabetic patients. The factors, inhibitors and activation products of coagulation and fibrinolysis measured were at best transiently affected by the diet. Only plasminogen activator inhibitory activity in plasma significantly increased during the dietary supplementation and returned to prediet values after cessation of n-3 fatty acids. Changes in PAI activity were negatively correlated to changes in serum triglycerides. We conclude that well adjusted type I diabetics show an almost unchanged haemostatic profile compared to matched healthy controls. A dietary intervention with n-3 fatty acids in these patients does not affect the plasmatic haemostatic pattern except for an increase in PAI activity.

Topics: Adult; Arteriosclerosis; Diabetes Mellitus, Type 1; Dietary Fats, Unsaturated; Docosahexaenoic Acids; Eicosapentaenoic Acid; Female; Fibrin; Fibrinogen; Fibrinolysis; Fibrinopeptide A; Hemostasis; Humans; Male; Plasminogen Inactivators; Tissue Plasminogen Activator

Topics: Adult; Blood Coagulation; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; False Positive Reactions; Female; Fibrin Fibrinogen Degradation Products; Fibrinolysis; Fibrinopeptide A; Fibrinopeptide B; Humans; Male; Middle Aged; Peptide Fragments

Factor X concentration and factor X activation, antithrombin III anti-Xa activity and plasma concentration, and fibrinopeptide A were measured in 20 diabetic patients and 20 normal subjects. Although factor X activation (81.3 +/- 2.2 vs 97.3 +/- 2.1%, p less than 0.01; mean +/- SE) and antithrombin III activity (76.5 +/- 2.2 vs 96.3 +/- 1.8%, p less than 0.01) were reduced in the diabetic patients, fibrinopeptide A concentration was increased (3.7 +/- 0.4 vs 1.7 +/- 0.2 ng ml-1, p less than 0.01). The ratio of factor X activation to antithrombin III anti-factor Xa activity was increased in the diabetic patients (1.10 +/- 0.01 vs 1.01 +/- 0.02, p less than 0.01). Induced hyperglycaemia was able to mimic all these abnormalities, without changing factor X or antithrombin III concentration. The results suggest that in vivo hyperglycaemia produces a decrease of factor X activation, but at the same time increases fibrinopeptide A formation due to a greater decrease of antithrombin III anti-Xa activity.

Topics: Adult; Antithrombin III; Blood Glucose; Diabetes Mellitus, Type 1; Factor X; Factor Xa; Female; Fibrinopeptide A; Humans; Hyperglycemia; Male; Reference Values; Thrombin

Platelet function (as production of thromboxane B2 by platelets stimulated with collagen, and plasma beta-thromboglobulin) and thrombin activity (as plasma fibrinopeptide A) were investigated in eight young (mean age 27 +/- 3 SE years) male patients in which type 1 diabetes mellitus had been diagnosed 2 to 6 months previously. They were all in excellent stable metabolic control (mean HbA1c 5.6 +/- 0.4 SE %) and free from any complications. The haemostatic variables were assessed at rest and after cycloergometric exercise to exhaustion. When compared to age- and sex-matched healthy controls, patients showed higher beta-thromboglobulin, fibrinopeptide A and thromboxane B2 at rest. After exercise, plasma beta-TG increased only in the controls. Platelet and thrombin activation are present in the very early stages of type 1 diabetes mellitus, in the absence of any complications.

Topics: Adult; beta-Thromboglobulin; Blood Platelets; Collagen; Diabetes Mellitus, Type 1; Exercise; Fibrinopeptide A; Humans; Male; Platelet Activation; Thromboxane B2

In the presence of increased levels of fibrinopeptide A, decreased antithrombin III biological activity, and thrombin-antithrombin III complex levels are seen in diabetic patients. Induced-hyperglycaemia in diabetic and normal subjects decreased antithrombin III activity and thrombin-antithrombin III levels, and increased fibrinopeptide A plasma levels, while antithrombin III concentration did not change; heparin was shown to reduced these phenomena. In diabetic patients, euglycaemia induced by insulin infusion restored antithrombin III activity, thrombin-antithrombin III complex and fibrinopeptide A concentrations; heparin administration had the same effects. These data stress the role of a hyperglycaemia-dependent decrease of antithrombin III activity in precipitating thrombin hyperactivity in diabetes mellitus.

Topics: Adult; Antithrombin III; Blood Glucose; Diabetes Mellitus, Type 1; Female; Fibrinopeptide A; Heparin; Humans; Hyperglycemia; Kinetics; Male; Peptide Hydrolases; Reference Values

Topics: Blood Coagulation; Chondroitin Sulfate Proteoglycans; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Fibrinopeptide A; Glycosaminoglycans; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Proteoglycans

To investigate the effect of blood glucose concentration on thrombin generation and fibrinolytic activity, six Type 1 patients had the blood glucose concentration maintained for 1 h at 5, 15, and 25 mmol l-1, and 8 patients underwent hypoglycaemia of 20 min duration after the blood glucose had been kept at 8 mmol l-1 for 1 h. During hyperglycaemia plasminogen activator activity rose from 214 (11-625) (median, range) to 478 (18-772) units (p less than 0.05) at a blood glucose of 5 mmol l-1 and to 511 (89-816) (p less than 0.05) and 535 (33-976) (p less than 0.05) units at a blood glucose of 15 and 25 mmol l-1, respectively. Cross-linked fibrin degradation products (FDP) were 45 and 53 micrograms l-1 at a blood glucose of 5 mmol l-1 and remained unchanged at higher glucose levels. Fibrinopeptide A was 1.3 (0.6-2.8) nmol l-1 at a blood glucose of 5 mmol l-1, and remained unchanged with hyperglycaemia, being 1.3 (0.9-1.3) nmol l-1 after 1h at 25 mmol l-1. During hypoglycaemia, plasminogen activator activity rose from 155 to 745 units (p less than 0.05) while both fibrinopeptide A and cross-linked FDP remained unchanged. The results indicate that acute fluctuations in blood glucose concentration do not lead to thrombin generation. Additionally, increased fibrinolytic activity measured in vitro is not associated with an increase in cross-linked FDP. This suggests that short-term hyper- and hypoglycaemia do not affect the end-products of the coagulation and fibrinolytic pathways.

Topics: Blood Glucose; Diabetes Mellitus, Type 1; Fibrin; Fibrinopeptide A; Glycated Hemoglobin; Humans; Hyperglycemia; Hypoglycemia; Male; Plasminogen Activators; Thrombin

Abnormalities of haemostasis are common in diabetes mellitus. As indicators of fibrinolysis and coagulation, plasmin and thrombin activity were assessed by assay of the fibrinogen peptide derivatives B beta 15-42 and fibrinopeptide A respectively in 60 diabetic patients and 50 control subjects in a cross-sectional study. Glycosylated haemoglobin (HbA1) correlated with B beta 15-42 (r = -0.26, p less than 0.05) and fibrinopeptide A (r = 0.30, p less than 0.05) in the diabetic patients suggesting that poor glycaemic control (i.e. high HbA1 levels) was associated with depressed plasmin and enhanced thrombin activity. Compared to controls, fibrinopeptide A levels were increased in diabetics (p less than 0.001) irrespective of sex or type of diabetes. B beta 15-42 levels were normal in diabetic females but increased in diabetic men (p less than 0.001) possibly secondary to the activation of coagulation. These results suggest that in diabetes mellitus activation of coagulation is the dominant haemostatic abnormality and that better glycaemic control could influence in-vivo plasmin and thrombin activity favourably.

Topics: Adult; Aged; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Fibrin Fibrinogen Degradation Products; Fibrinolysin; Fibrinopeptide A; Fibrinopeptide B; Glycated Hemoglobin; Hemostasis; Humans; Male; Middle Aged; Peptide Fragments; Thrombin

To determine the relationship between thrombin generation and platelet secretion in vivo in diabetes mellitus, we measured simultaneous plasma beta-thromboglobulin (BTG) and fibrinopeptide A (FPA) in 40 insulin-dependent patients without renal disease, and 20 control subjects of similar age. Log mean plasma BTG and FPA were higher in diabetic patients (32.1 vs 23.7 ng/ml, and 2.83 vs 1.49 ng/ml, p less than 0.001 and less than 0.005, respectively). Neither was correlated with plasma glucose or hemoglobin AI. Plasma BTG and FPA were moderately intercorrelated in control subjects (r = +0.36, p = 0.03), but not in diabetic patients (r = +0.09, p = NS). Thus, in diabetes mellitus, thrombin generation as a contributing mechanism to platelet secretion is probably overshadowed by thrombin-independent mechanisms.

Topics: Adult; Age Factors; Aged; beta-Thromboglobulin; Blood Platelets; Diabetes Mellitus, Type 1; Female; Fibrinopeptide A; Humans; Male; Middle Aged; Sex Factors; Thrombin

Plasma and urine fibrinopeptide-A (FPA) levels were investigated in type I and II diabetic patients. Plasma FPA and 24-h urinary excretion of FPA were significantly elevated in diabetic patients compared with normal volunteers, indicating augmented thrombin activity in diabetes. Plasma and urine FPA did not differ between type I and type II diabetic subjects. Comparison of plasma FPA with blood glucose and hemoglobin A1 (HbA1) indicated that elevation of FPA is rapidly reversible and intermittent during hypo- and hyperglycemia. Although elevated plasma FPA was seen in patients of short as well as long duration of diabetes, plasma and urine FPA correlated with duration of diabetes in type I patients. In type I diabetic patients with vascular complications, hyperglycemia induced by an oral glucose challenge was accompanied by elevation of plasma FPA and acceleration of fibrinogen disappearance. These responses were not seen when the patients were treated with intravenous (i.v.) heparin before the glucose challenge. In patients without vascular complications, there was also an acceleration of fibrinogen disappearance and a marginal (not statistically significant) elevation of plasma FPA seen after the FPA response observed in vascular disease patients. In all patients, induced hyperglycemia resulted in a decrease in hematocrit and hemoglobin (blood volume expansion) and an increase in pulse pressure indicating hemodynamic changes. The association of hyperglycemia and hemodynamic changes with augmented thrombin activity is consistent with a mechanism for fibrin formation and deposition based on endothelial injury and/or increased vascular permeability. Fibrin deposition due to such a mechanism may participate in the development of the vascular complications of diabetes.

Topics: Adolescent; Adult; Blood Glucose; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Female; Fibrinogen; Fibrinopeptide A; Glucose; Hemodynamics; Humans; Male; Middle Aged

Plasma beta-thromboglobulin, platelet factor 4, fibrinogen, fibrinopeptide A, antithrombin III, factor VIII related antigen, alpha 2-macroglobulin, platelet count, and total glycosylated haemoglobin were measured in three well matched groups of subjects: non-diabetic controls, diabetics without retinopathy, and diabetics with proliferative retinopathy. beta-thromboglobulin and platelet factor 4 concentrations were significantly higher in the diabetics with retinopathy than in the controls and platelet factor 4 was also increased in the diabetics without retinopathy compared with controls. Fibrinogen concentration was raised in diabetics without retinopathy compared with controls, diabetics with retinopathy compared with controls, and diabetics with retinopathy compared with those without. Fibrinopeptide A concentration did not differ significantly between groups. Antithrombin III levels were increased in diabetics with retinopathy compared with controls, and in diabetics with retinopathy compared with those without. Factor VIII related antigen values were higher in both the diabetic groups when compared with the controls. Fibrinopeptide A concentration correlated with both beta-thromboglobulin and platelet factor 4 in each of the three groups. Haemostatic abnormalities in diabetes have been shown, although a hypercoagulable state has not been confirmed. These changes in platelet and coagulation function may be secondary to the development of microvascular disease and their role in the pathogenesis of retinopathy remains uncertain.

Topics: Adult; alpha-Macroglobulins; Antigens; Antithrombin III; beta-Thromboglobulin; Blood Coagulation Factors; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Factor VIII; Female; Fibrinogen; Fibrinopeptide A; Glycated Hemoglobin; Humans; Male; Platelet Count; Platelet Factor 4; von Willebrand Factor