fibrinopeptide-a and Diabetic-Nephropathies

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

The aim of the present study was to clarify the role of intrarenal coagulation in the progression of renal dysfunction and to assess the efficacy of anticoagulant therapy in diabetic nephropathy patients. Forty-one diabetic patients were divided into 2 groups: group 1 (G-1), 20 patients with nephropathy; and group 2 (G-2), 21 patients without nephropathy. The levels of fibrinopeptide A (FPA) and fibrinopeptide B beta 15-42 (FPB beta 15-42), fibrin/fibrinogen degradation products-D dimer (FDP-D dimer), and FDP-E products (FDP-E) and FDP, which are sensitive parameters of coagulation and fibrinolysis, were measured by radioimmunoassay, enzyme immunoassay (EIA), and latex photometric immunoassay, respectively, in both the blood and urine. The levels of urinary FPA, FDP-D, FDP-E, and FDP were found to be much higher in G-1 than in G-2. Significant relations were observed among the urinary levels of these four parameters. The renal function in all cases with higher levels of urinary parameters was severely deteriorated. Following heparin administration to these patients, marked reductions of the urinary FPA, FDP-D, and FDP-E and improvement of nephrotic syndrome were observed. The present data suggest that in diabetic nephropathy: (1) intrarenal coagulation is likely to occur and to induce progression of renal dysfunction; and (2) heparin therapy could be effective in diabetic nephropathy when the patients are selected according to the above parameters of coagulation and fibrinolysis.

Topics: Adult; Aged; Blood Coagulation; Diabetic Nephropathies; Female; Fibrin Fibrinogen Degradation Products; Fibrinolysis; Fibrinopeptide A; Fibrinopeptide B; Heparin; Humans; Kidney; Male; Middle Aged; Peptide Fragments

In 6 patients on continuous ambulatory peritoneal dialysis we investigated the inhibition of intraperitoneal fibrin formation by heparin. A continuous addition of 500 U of heparin per liter dialysate was used for 52 h. In plasma no heparin activity could be detected, even 52 h after intraperitoneal administration of heparin. The fibrin formation was determined by fibrinopeptide A, a thrombin-induced split product of fibrinogen. In patients under regular continuous ambulatory peritoneal dialysis we determined the fibrinopeptide A concentrations in plasma. The values were comparable with the fibrinopeptide A concentrations measured in disseminated intravascular coagulopathy. They decreased during intraperitoneal administration of heparin from 63.2 +/- 11.8 to 4.9 +/- 1.7 ng/ml. The fibrinopeptide A concentration in the 4-hour intraperitoneal dialysate (155.8 +/- 15.7 ng/ml) decreased after heparin administration to 8.5 +/- 2.0 ng/ml and was always higher than in plasma. We conclude that 500 U heparin per liter dialysate prevents the intraperitoneal fibrin formation. The low antithrombin III concentration (0.44 +/- 0.13 mg/dl) in protein-poor dialysate seems to be sufficient to inhibit the thrombin activity after acceleration by heparin.

Topics: Ascitic Fluid; Diabetic Nephropathies; Female; Fibrinogen; Fibrinopeptide A; Heparin; Humans; Kidney Failure, Chronic; Male; Peritoneal Dialysis, Continuous Ambulatory; Solutions