fibrin and Diabetes-Mellitus--Type-2

Accelerated atherosclerosis is the main underlying factor contributing to the high risk of atherothrombotic events in patients with diabetes mellitus and atherothrombotic complications are the main cause of mortality. Like with many bodily systems, pathology is observed when the normal processes are exaggerated or uncontrolled. This applies to the processes of coagulation and thrombosis as well. In diabetes, in fact, the balance between prothrombotic and fibrinolytic factors is impaired and thus the scale is tipped towards a prothrombotic and hypofibrinolytic milieu, which in association with the vascular changes accompanying plaque formation and ruptures, increases the prevalence of ischaemic events such as angina and myocardial infarction. Apart from traditional, modifiable risk factors for cardiovascular disease like hypertension, smoking, elevated cholesterol; rheological properties, endogenous fibrinolysis and impaired platelet activity are rapidly gaining significance in the pathogenesis of atherosclerosis especially in diabetic subjects. Blood clot formation represents the last step in the athero-thrombotic process, and the structure of the fibrin network has a role in determining predisposition to cardiovascular disease. It is no surprise that just like platelets and fibrin networks, erythrocytes have been shown to play a role in coagulation as well. This is in striking contrast to their traditional physiological role of oxygen transport. In fact, emerging evidence suggests that erythrocytes enhance functional coagulation properties and platelet aggregation. Among the spectrum of haematological abnormalities in diabetes, erythrocyte aggregation and decreased deformability of erythrocytes predominate. More importantly, they are implicated in the pathogenesis of microvascular complications of diabetes. The morphology of platelets, fibrin networks and erythrocytes are thus essential role players in unravelling the pathogenesis of cardiovascular complications in diabetic subjects.

Topics: Animals; Atherosclerosis; Blood Coagulation; Blood Platelets; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Erythrocytes; Fibrin; Fibrinolysis; Humans; Plaque, Atherosclerotic; Risk Assessment; Risk Factors; Thrombosis

Despite increased atherothrombotic risk in type 2 diabetes mellitus, (T2DM) the best preventative antithrombotic strategy remains undetermined. We defined the effects of three antiplatelet agents on functional readout and biomarker kinetics in platelet activation and coagulation in patients with T2DM.. 56 patients with T2DM were randomised to antiplatelet monotherapy with aspirin 75 mg once daily (OD), clopidogrel 75 mg OD or prasugrel 10 mg OD during three periods of a crossover study. Platelet aggregation (PA) was determined by light-transmittance aggregometry and P-selectin expression by flow cytometry. Markers of fibrin clot dynamics, inflammation and coagulation were measured. Plasma levels of 14 miRNA were assessed by quantitative polymerase chain reactions.. Of the 56 patients, 24 (43%) were receiving aspirin for primary prevention of ischaemic events and 32 (57%) for secondary prevention. Prasugrel was the strongest inhibitor of ADP-induced PA (mean ± SD maximum response to 20μmol/L ADP 77.6 ± 8.4% [aspirin] vs. 57.7 ± 17.6% [clopidogrel] vs. 34.1 ± 14.1% [prasugrel], p < 0.001), P-selectin expression (30 μmol/L ADP; 45.1 ± 21.4% vs. 27.1 ± 19.0% vs. 14.1 ± 14.9%, p < 0.001) and collagen-induced PA (2 μg/mL; 62.1 ± 19.4% vs. 72.3 ± 18.2% vs. 60.2 ± 18.5%, p < 0.001). Fibrin clot dynamics and levels of coagulation and inflammatory proteins were similar. Lower levels of miR-24 (p = 0.004), miR-191 (p = 0.019), miR-197 (p = 0.009) and miR-223 (p = 0.014) were demonstrated during prasugrel-therapy vs. aspirin. Circulating miR-197 was lower in those cardiovascular disease during therapy with aspirin (p = 0.039) or prasugrel (p = 0.0083).. Prasugrel monotherapy in T2DM provided potent platelet inhibition and reduced levels of a number of platelet-associated miRNAs. miR-197 is a potential marker of cardiovascular disease in this population. Clinical outcome studies investigating prasugrel monotherapy are warranted in individuals with T2DM. Trial registration EudraCT, 2009-011907-22. Registered 15 March 2010, https://www.clinicaltrialsregister.eu/ctr-search/trial/2009-011907-22/GB.

Topics: Aged; Aspirin; Biomarkers; Blood Coagulation; Clopidogrel; Cross-Over Studies; Diabetes Mellitus, Type 2; Double-Blind Method; Female; Fibrin; Humans; Male; MicroRNAs; Middle Aged; P-Selectin; Platelet Aggregation; Platelet Aggregation Inhibitors; Prasugrel Hydrochloride; Primary Prevention; Secondary Prevention; Thrombosis; Time Factors; Treatment Outcome

Diabetic subjects have been shown to have altered fibrin network structures. One possible cause may be fibrinogen glycation resulting in altered structure/function properties. We investigated the effect of glucose control on fibrinogen glycation and fibrin network structure in type 2 diabetes. Blood samples were taken from twenty uncontrolled diabetic subjects at baseline to determine the levels of fibrinogen glycation and fibrin network structures. The subjects were then treated with insulin until blood glucose control was achieved before end blood samples were taken. Twenty age- and BMI-matched non-diabetic subjects were included as a reference group. The diabetic subjects had significantly higher mean fibrinogen glycation at baseline than the non-diabetic subjects (7.84 vs. 3.89 mol glucose / mol fibrinogen; p < 0.001). This was significantly reduced during the intervention (7.84 to 5.24 mol glucose / mol fibrinogen; p < 0.0002) in the diabetic group. Both groups had high mean fibrinogen concentrations (4.25 and 4.02 g/l, diabetic and non-diabetic subjects respectively). There was no difference in fibrinogen concentration, porosity, compaction and kinetics of clot formation between the diabetic subjects and non-diabetic subjects at baseline, nor were there any changes during the intervention despite the reduced fibrinogen glycation. Fibrin network characteristics correlated well with fibrinogen but not with any markers of glycaemic control. Improved glycaemic control resulted in decreased fibrinogen glycation but not fibrinogen concentration. It seems as though porosity, compaction and kinetics of clot formation are more related to fibrinogen concentration than fibrinogen glycation in this model.

Topics: Adult; Aged; Blood Coagulation; Blood Glucose; Diabetes Mellitus, Type 2; Female; Fibrin; Fibrinogen; Glycosylation; Humans; Insulin; Male; Middle Aged; Porosity

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are antihyperglycemic drugs that decrease mortality from cardiovascular diseases. However, their effects on hemostasis in the cardioprotective effects have not been evaluated. Therefore, the effects of canagliflozin (CANA, 100 mg/kg, p.o.) and dapagliflozin (DAPA, 10 mg/kg, p.o.) on the parameters of hemostasis were investigated in female and male normoglycemic and streptozotocin (180 mg/kg, i.p.)-induced diabetic mice. CANA and DAPA reduced platelet activity in thrombus in male and female mice both normoglycemic and diabetic. CANA decreased thrombus formation in diabetic male mice, and platelet activation to ADP in diabetic female and male mice. Activation of fibrinolysis was observed in female mice, both normoglycemic and diabetic. DAPA reduced thrombus formation in diabetic male and female mice, and decreased platelet activation to ADP and fibrin formation in diabetic male mice. DAPA increased fibrin formation in normoglycemic female mice and activated fibrinolysis in diabetic female mice. CANA and DAPA exerted sex-specific effects, which were more pronounced in hyperglycemia. The antithrombotic effect of CANA and DAPA was more noticeable in male mice and could be due to platelet inhibition. The effect on coagulation and fibrinolysis was not clear since an increased coagulation and fibrinolysis were observed only in female mice.

Topics: Animals; Canagliflozin; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Female; Fibrin; Male; Mice; Mice, Obese; Platelet Activation; Sodium-Glucose Transporter 2 Inhibitors

To describe the healing outcome of chronic, hard-to-heal diabetic foot ulcers (DFUs) treated with an autologous multilayered leukocyte, platelet, and fibrin (MLPF) patch in addition to the best standard of care, in a real-world clinical setting of two US amputation preventive centers.. In this retrospective study of patients treated between September 2021 and October 2022, the authors analyzed DFU healing outcomes based on Wound, Ischemia, and foot Infection-derived amputation risk.. All 36 patients had a diagnosis of type 2 diabetes and 29 (81%) were male. Their average age was 61.4 years, body mass index was 29.2 kg/m2, and glycated hemoglobin was 7.9. Twenty-seven patients (78%) were diagnosed with peripheral vascular disease, 20 (56%) underwent a peripheral vascular procedure, 15 (42%) had a prior amputation, and 6 (17%) were on hemodialysis. Average wound size was 4.9 cm2, and wound age was 9.5 months. Twelve patients (32%) were classified as low risk, 15 (39%) as moderate risk, and 11 (29%) as high risk for amputation. Within 12 weeks of the first MLPF patch application, nine wounds (24%) healed. After 20 weeks, 23 wounds (61%) were closed, and by follow-up, 30 wounds (79%) healed. No amputations were noted. Compared with published data, 40% fewer patients underwent readmission within 30 days, with 72% shorter admission duration.. Real-world clinical experiences using the MLPF patch to treat hard-to-heal DFUs resulted in the majority of wounds healing. Few patients experienced a readmission within 30 days, and the average admission duration was short.

Topics: Diabetes Mellitus, Type 2; Diabetic Foot; Female; Fibrin; Humans; Infant; Leukocytes; Male; Middle Aged; Retrospective Studies

Mortality after coronary artery bypass grafting (CABG) is primarily thromboembolic by nature. We investigated whether impaired fibrinolysis observed in cardiovascular diseases is associated with long-term mortality following CABG.. The study population comprised 292 consecutive patients (aged 64.6 ± 8.1 years) who underwent scheduled CABG. We measured plasma clot lysis time (CLT) preoperatively as a measure of fibrinolysis capacity. Cardiovascular and all-cause deaths were recorded during a median follow-up of 13.8 years.. CLT positively correlated with age (r = .56, p < .001), fibrinogen (r = .25, p = .002) and EuroSCORE I (r = .32, p < .001). The cardiovascular and overall mortality rates were 3.0 and 4.9 per 100 patient-years (32.4% vs 52.8%) respectively. In patients who died from cardiovascular and all causes, CLT was prolonged compared with survivors (both p < .050). Multivariable Cox regression analysis adjusted for potential confounders showed that long-term cardiovascular and all-cause deaths were associated with CLT (HR per 10 min 1.206; 95% CI 1.037-1.402, p = .015 and HR 1.164; 96% CI 1.032-1.309, p = .012), low-density lipoprotein cholesterol (HR per 1 mmol/L 1.556; 95% CI 1.205-2.010, p < .001 and HR 1.388; 96% CI 1.125-1.703, p = .002), C-reactive protein (HR per 10 mg/L 1.171; 95% CI 1.046-1.312, p = .006 and HR 1.127; 95% CI 1.005-1.237, p = .022) and EuroSCORE I (HR 1.173; 95% CI 1.016-1.355, p = .030 and HR 1.183; 95% CI 1.059-1.317, p = .003 respectively). Type 2 diabetes was solely associated with overall mortality (HR 1.594; 96% CI 1.088-2.334, p = .017).. In this study, we showed that reduced fibrin clot susceptibility to fibrinolysis is weekly associated with long-term mortality in advanced CAD.

Topics: Coronary Artery Bypass; Coronary Artery Disease; Diabetes Mellitus, Type 2; Fibrin; Fibrin Clot Lysis Time; Follow-Up Studies; Humans; Treatment Outcome

Fibrin(ogen) amyloid microclots and platelet hyperactivation previously reported as a novel finding in South African patients with the coronavirus 2019 disease (COVID-19) and Long COVID/Post-Acute Sequelae of COVID-19 (PASC), might form a suitable set of foci for the clinical treatment of the symptoms of Long COVID/PASC. A Long COVID/PASC Registry was subsequently established as an online platform where patients can report Long COVID/PASC symptoms and previous comorbidities.. In this study, we report on the comorbidities and persistent symptoms, using data obtained from 845 South African Long COVID/PASC patients. By using a previously published scoring system for fibrin amyloid microclots and platelet pathology, we also analysed blood samples from 80 patients, and report the presence of significant fibrin amyloid microclots and platelet pathology in all cases.. Hypertension, high cholesterol levels (dyslipidaemia), cardiovascular disease and type 2 diabetes mellitus (T2DM) were found to be the most important comorbidities. The gender balance (70% female) and the most commonly reported Long COVID/PASC symptoms (fatigue, brain fog, loss of concentration and forgetfulness, shortness of breath, as well as joint and muscle pains) were comparable to those reported elsewhere. These findings confirmed that our sample was not atypical. Microclot and platelet pathologies were associated with Long COVID/PASC symptoms that persisted after the recovery from acute COVID-19.

Topics: Amyloid; COVID-19; Diabetes Mellitus, Type 2; Female; Fibrin; Humans; Male; Post-Acute COVID-19 Syndrome; Prevalence; SARS-CoV-2

Branch Retinal Vein Occlusion (BRVO) is the second chronic branch retinal vascular disease that causes abnormal vision loss after acute branch retinal disease in type 2 diabetes. There is no scientific conclusion about its specific pathogenic mechanism at present. Most clinical scholars generally support the theory that the partial human anatomical structure and various systemic risk psychological factors cause insufficient oxygen supply and hemostasis in the local branch retinal arteries. The research results of this article aim to reconstruct a non-nanocell-targeted thrombolytic drug delivery system without modification of rtPA without polyethylene glycol-methyl polycaprolactone and to re-evaluate its thrombus targeting and dissolution. The effect and safety of thrombus provide a new strategy for realizing combined treatment of thrombus. It is a study on the targeting of rtPA-NP to thrombus and its thrombolytic properties. HPLC method was used to detect the binding of fibrin clot prepared in vitro with coumarin-6 labeled NP and rtPA-NP; immunofluorescence technique was used to observe the location of nanomedicine and fibrin clot in branch retinal vein occlusion model Condition. The rtPA-NP drug delivery system constructed in this study not only retains the activity of rtPA and good thrombus targeting but also significantly prolongs its half-life and simplifies the way of administration. The therapeutic efficiency of rtPA-NP thrombus targeted administration on branch retinal vein occlusion reached 85.64%. The successful construction of the rtPA-NP thrombus targeted drug delivery system provides a new way for thrombosis treatment and lays the foundation for the future combination of anticoagulants and vascular protection drugs to achieve the combined treatment of thrombosis and the development of safe and efficient thrombolytic drugs.

Topics: Diabetes Mellitus, Type 2; Fibrin; Fibrinolytic Agents; Humans; Nanoparticles; Recombinant Proteins; Retinal Vein Occlusion; Thrombolytic Therapy; Thrombosis; Tissue Plasminogen Activator

Obesity predisposes individuals to metabolic syndrome, which increases the risk of cardiovascular diseases, non-alcoholic fatty liver disease (NAFLD), and type 2 diabetes. A pathological manifestation of obesity is the activation of the coagulation system. In turn, extravascular fibrin(ogen) deposits accumulate in adipose tissues and liver. These deposits promote adiposity and downstream sequelae by driving pro-inflammatory macrophage function through binding the leukocyte integrin receptor α. An unresolved question is whether conversion of soluble fibrinogen to a crosslinked fibrin matrix is required to exacerbate obesity-driven diseases.. Here, fibrinogen-deficient/depleted mice (Fib- or treated with siRNA against fibrinogen [siFga]), mice expressing fibrinogen that cannot polymerize to fibrin (Fib. Consistent with prior studies, Fib

Topics: Afibrinogenemia; Animals; Diabetes Mellitus, Type 2; Diet; Factor XIII; Fibrin; Fibrinogen; Hemostatics; Mice; Non-alcoholic Fatty Liver Disease; Obesity; Polymers

Post-acute sequelae of COVID-19 (PASC), also now known as long COVID, has become a major global health and economic burden. Previously, we provided evidence that there is a significant insoluble fibrin amyloid microclot load in the circulation of individuals with long COVID, and that these microclots entrap a substantial number of inflammatory molecules, including those that might prevent clot breakdown. Scientifically, the most challenging aspect of this debilitating condition is that traditional pathology tests such as a serum CRP (C-reactive protein) may not show any significant abnormal inflammatory markers, albeit these tests measure only the soluble inflammatory molecules. Elevated, or abnormal soluble biomarkers such as IL-6, D-Dimer or fibrinogen indicate an increased risk for thrombosis or a host immune response in COVID-19. The absence of biomarkers in standard pathology tests, result in a significant amount of confusion for patients and clinicians, as patients are extremely sick or even bed-ridden but with no regular identifiable reason for their disease. Biomarkers that are currently available cannot detect the molecules present in the microclots we identified and are therefore unable to confirm their presence or the mechanisms that drive their formation.. Here we analysed the protein content of double-digested microclots of 99 long COVID patients and 29 healthy controls. The patients suffering from long COVID reported their symptoms through a questionnaire completed by themselves or their attending physician.. Our long COVID cohort's symptoms were found to be in line with global findings, where the most prevalent symptoms were constant fatigue (74%,) cognitive impairment (71%) and depression and anxiety (30%). Our most noteworthy findings were a reduced level of plasma Kallikrein compared to our controls, an increased level of platelet factor 4 (PF4) von Willebrand factor (VWF), and a marginally increased level of α-2 antiplasmin (α-2-AP). We also found a significant presence of antibodies entrapped inside these microclots.. Our results confirm the presence of pro-inflammatory molecules that may also contribute to a failed fibrinolysis phenomenon, which could possibly explain why individuals with long COVID suffer from chronic fatigue, dyspnoea, or cognitive impairment. In addition, significant platelet hyperactivation was noted. Hyperactivation will result in the granular content of platelets being shed into the circulation, including PF4. Overall, our results provide further evidence of both a failed fibrinolytic system in long COVID/PASC and the entrapment of many proteins whose presence might otherwise go unrecorded. These findings might have significant implications for individuals with pre-existing comorbidities, including cardiovascular disease and type 2 diabetes.

Topics: alpha-2-Antiplasmin; Biomarkers; C-Reactive Protein; COVID-19; Diabetes Mellitus, Type 2; Fibrin; Fibrinogen; Humans; Interleukin-6; Plasma Kallikrein; Platelet Factor 4; Post-Acute COVID-19 Syndrome; Proteomics; Thrombosis; von Willebrand Factor

Acetylsalicylic acid (ASA) and type 2 diabetes mellitus (T2DM) affect fibrin clot properties through fibrinogen acetylation or glycation. We aimed to identify glycation and acetylation sites on fibrinogen in plasma fibrin clot of T2DM patients with respect to effects of ASA and fibrin clot properties. In fibrin clots generated from plasma of 9 T2DM patients, we performed mass-spectrometric analysis of Nε-fructosyl-(FL), Nε-carboxyethyl-(CEL) and Nε-carboxymethyl-lysine (CML), and acetylation sites, before and after one-month administration of 75 mg/d ASA confirmed with determination of thromboxane B2 concentration (TXB

Topics: Acetylation; Aspirin; Diabetes Mellitus, Type 2; Fibrin; Fibrinogen; Fibrinolysis; Humans; Proteomics

Type 2 diabetes mellitus (T2DM) is associated with hypofibrinolysis and increased factor XIII-mediated α2-antiplasmin incorporation into the fibrin clot. It is unclear whether there are sex-related differences in α2-antiplasmin incorporation in relation to impaired clot lysis in T2DM.. We investigated α2-antiplasmin incorporation into fibrin clots as a determinant of clot lysability in patients of both sexes with T2DM.. In a group of 113 T2DM patients, 54 (47.8%) of which were women, we investigated α2-antiplasmin incorporation using an in-house sandwich enzyme-linked immunoassay and plasma clot lysis by turbidimetry, along with fibrinogen and thrombin generation using calibrated automated thrombogram and factor XIII activity.. Female patients had 15.2% greater α2-antiplasmin incorporation into the fibrin clot (p = 0.008) and slightly higher plasma α2-antiplasmin concentration (p = 0.005) along with 8.4% longer time to 50% lysis (Lys50. This study suggests that a more compromised fibrinolysis in diabetic women when compared with men could be in part mediated by increased α2-antiplasmin incorporation into the fibrin.

Topics: alpha-2-Antiplasmin; Antifibrinolytic Agents; Diabetes Mellitus, Type 2; Female; Fibrin; Fibrin Clot Lysis Time; Fibrinolysis; Humans; Male

Forensic investigations generally contain extensive morphological examinations to accurately diagnose the cause of death. Thus, the appearance of a new disease often creates emerging challenges in morphological examinations due to the lack of available data from autopsy- or biopsy-based research. Since late December 2019, an outbreak of a novel seventh coronavirus disease has been reported in China caused by "severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2). On March 11, 2020, the new clinical condition COVID-19 (Corona-Virus-Disease-19) was declared a pandemic by the World Health Organization (WHO). Patients with COVID-19 mainly have a mild disease course, but severe disease onset might result in death due to proceeded lung injury with massive alveolar damage and progressive respiratory failure. However, the detailed mechanisms that cause organ injury still remain unclear. We investigated the morphological findings of a COVID-19 patient who died during self-isolation. Pathologic examination revealed massive bilateral alveolar damage, indicating early-phase "acute respiratory distress syndrome" (ARDS). This case emphasizes the possibility of a rapid severe disease onset in previously mild clinical condition and highlights the necessity of a complete autopsy to gain a better understanding of the pathophysiological changes in SARS-CoV-2 infections.

Topics: Alveolar Epithelial Cells; Autopsy; Betacoronavirus; Coronavirus Infections; Cough; COVID-19; Diabetes Mellitus, Type 2; Fever; Fibrin; Fibrosis; Humans; Hyperplasia; Hypertension; Lung; Lymphocytes; Macrophages; Male; Megakaryocytes; Metaplasia; Middle Aged; Neutrophils; Pandemics; Pneumonia, Viral; Quarantine; SARS-CoV-2; Tachycardia; Thrombosis

: In type 2 diabetes mellitus (T2DM), increased α2-antiplasmin incorporation in fibrin and impaired fibrinolysis have been reported. Acetylsalicylic acid (ASA), used in cardiovascular prevention, modulates fibrinolysis and exerts weaker therapeutic effect in this disease. We investigated how glycation and acetylation of α2-antiplasmin affects its interaction with fibrin. Using surface plasmon resonance, we analyzed fibrin binding by α2-antiplasmin incubated with no β-D-glucose or ASA (control); incubated with β-D-glucose (5, 10, 50 mmol/l); (3) incubated with 1.6 mmol/l acetylsalicylic acid (ASA) and (4) incubated with 1.6 mmol/l ASA and 50 mmol/l β-D-glucose. Incubation with glucose decreased affinity of α2-antiplasmin for fibrin compared with control α2-antiplasmin in a glucose concentration-depending manner. α2-Antiplasmin incubation with ASA did not affect its affinity to fibrin. α2-Antiplasmin incubation with ASA and glucose resulted in 4.2-fold increased affinity to fibrin compared with α2-antiplasmin incubated with 50 mmol/l glucose (P < 0.001). In conclusion, α2-antiplasmin incubation with glucose at concentrations encountered in T2DM is associated with decreased binding affinity of α2-antiplasmin to fibrin. ASA alone does not affect the binding affinity of α2-antiplasmin to fibrin, but partly reverses the effect introduced by the incubation with 50 mmol/l glucose. This study suggests new mechanisms involved in regulating fibrinolysis efficiency in hyperglycemia.

Topics: Acetylation; alpha-2-Antiplasmin; Blood Coagulation; Diabetes Mellitus, Type 2; Fibrin; Fibrinolysis; Glycosylation; Humans; Hyperglycemia

Laminin, as a key component of the basement membrane extracellular matrix (ECM), regulates tissue morphogenesis. Here, we show that multiple laminin isoforms promiscuously bind to growth factors (GFs) with high affinity, through their heparin-binding domains (HBDs) located in the α chain laminin-type G (LG) domains. These domains also bind to syndecan cell-surface receptors, promoting attachment of fibroblasts and endothelial cells. We explore the application of these multifunctional laminin HBDs in wound healing in the type-2 diabetic mouse. We demonstrate that covalent incorporation of laminin HBDs into fibrin matrices improves retention of GFs and significantly enhances the efficacy of vascular endothelial cell growth factor (VEGF-A165) and platelet-derived growth factor (PDGF-BB) in promoting wound healing in vivo, under conditions where the GFs alone in fibrin are inefficacious. This laminin HBD peptide may be clinically useful by improving biomaterial matrices as both GF reservoirs and cell scaffolds, leading to effective tissue regeneration.

Topics: Animals; Binding Sites; Cells, Cultured; Diabetes Mellitus, Type 2; Fibrin; Heparin; Humans; Intercellular Signaling Peptides and Proteins; Laminin; Male; Mice, Inbred C57BL; Peptides; Protein Binding; Skin; Wound Healing

Many chronic diseases, including those classified as cardiovascular, neurodegenerative, or autoimmune, are characterized by persistent inflammation. The origin of this inflammation is mostly unclear, but it is typically mediated by inflammatory biomarkers, such as cytokines, and affected by both environmental and genetic factors. Recently circulating bacterial inflammagens such as lipopolysaccharide (LPS) have been implicated. We used a highly selective mouse monoclonal antibody to detect bacterial LPS in whole blood and/or platelet poor plasma of individuals with Parkinson's Disease, Alzheimer's type dementia, or Type 2 Diabetes Mellitus. Our results showed that staining is significantly enhanced (P < 0.0001) compared to healthy controls. Aberrant blood clots in these patient groups are characterized by amyloid formation as shown by the amyloid-selective stains thioflavin T and Amytracker™ 480 or 680. Correlative Light-Electron Microscopy (CLEM) illustrated that the LPS antibody staining is located in the same places as where amyloid fibrils may be observed. These data are consistent with the Iron Dysregulation and Dormant Microbes (IDDM) hypothesis in which bacterial inflammagens such as LPS are responsible for anomalous blood clotting as part of the aetiology of these chronic inflammatory diseases.

Topics: Aged; Alzheimer Disease; Amyloid; Blood Coagulation; Blood Specimen Collection; Diabetes Mellitus, Type 2; Female; Fibrin; Humans; Inflammation; Lipopolysaccharides; Male; Microscopy, Electron; Middle Aged; Parkinson Disease; Protein Binding

Type 2 diabetes is associated with faster formation of poorly lysable, denser fibrin clots and elevated cellular fibronectin (cFn), a marker of vascular injury. We investigated whether cFn affects clot properties in type 2 diabetes. In 200 consecutive patients with type 2 diabetes and 100 control subjects matched for age and sex, we determined plasma cFn along with clot formation and degradation using turbidimetric and permeability assays. Diabetic patients had elevated cFn (median, 3.99 [interquartile range, 2.87-4.81] µg/ml]), increased clot density (MaxAbsC) and prolonged lysis time (LysT) compared with those without type 2 diabetes (all p<0.01). Diabetic patients with documented cardiovascular disease (CVD, n=127, 63.5 %) had increased cFn (4.53 [3.68-4.95] µg/ml), decreased clot permeability (Ks) and increased MaxAbsC compared with those without CVD (all p<0.001). Diabetic patients with cFn in the top quartile (>4.81 µg/ml) were two times more likely to have CVD compared with those in the lowest quartile (odds ratio 1.80, 95 % confidence interval 1.41-2.46, p<0.001). No differences in cFn were observed in relation to microvascular complications. After adjustment for potential confounders, cFn accounted for 10.2 % of variance in Ks, 18.2 % of variance in clot density and 10.2 % of variance in AUC in diabetic patients. This study shows that elevated cFn is associated with unfavourably modified clot properties in type 2 diabetes, especially with concomitant CVD, which indicates novel links between vascular injury and prothrombotic alterations in diabetes. Coagulation, cellular fibronectin, type 2 diabetes, cardiovascular disease.

Topics: Aged; Biomarkers; Blood Coagulation; Cardiovascular Diseases; Case-Control Studies; Chi-Square Distribution; Diabetes Mellitus, Type 2; Female; Fibrin; Fibrinolysis; Fibronectins; Humans; Linear Models; Logistic Models; Male; Middle Aged; Multivariate Analysis; Odds Ratio; Risk Assessment; Risk Factors; Thrombosis; Up-Regulation

Type 2 diabetes (T2D) has many cardiovascular complications, including a thrombotic propensity. Many such chronic, inflammatory diseases are accompanied (and may be exacerbated, and possibly even largely caused) by amyloid fibril formation. Recognising that there are few strong genetic associations underpinning T2D, but that amyloidogenesis of amylin is closely involved, we have been seeking to understand what might trigger the disease. Serum levels of bacterial lipopolysaccharide are raised in T2D, and we recently showed that fibrin(ogen) polymerisation during blood clotting can be affected strongly by LPS. The selectivity was indicated by the regularisation of clotting by lipopolysaccharide-binding protein (LBP). Since coagulopathies are a hallmark of T2D, we wondered whether they might too be caused by LPS (and reversed by LBP). We show here, using SEM and confocal microscopy, that platelet-poor-plasma from subjects with T2D had a much greater propensity for hypercoagulability and for amyloidogenesis, and that these could both be reversed by LBP. These data imply that coagulopathies are an important feature of T2D, and may be driven by 'hidden' LPS. Given the prevalence of amyloid formation in the sequelae of diabetes, this opens up novel strategies for both the prevention and treatment of T2D.

Topics: Acute-Phase Proteins; Adult; Aged; Aged, 80 and over; Amyloid; Blood Coagulation Disorders; Carrier Proteins; Diabetes Mellitus, Type 2; Female; Fibrin; Humans; Male; Membrane Glycoproteins; Microscopy, Confocal; Microscopy, Electron, Scanning; Middle Aged; Plasma

We have previously shown that many chronic, inflammatory diseases are accompanied, and possibly partly caused or exacerbated, by various coagulopathies, manifested as anomalous clots in the form of 'dense matted deposits'. More recently, we have shown that these clots can be amyloid in nature, and that the plasma of healthy controls can be induced to form such clots by the addition of tiny amounts of bacterial lipopolysaccharide or lipoteichoic acid. Type 2 diabetes (T2D) is also accompanied by raised levels of LPS.. We use superresolution and confocal microscopies to investigate the amyloid nature of clots from healthy and T2D individuals.. We show here, with the established stain thioflavin T and the novel stains Amytracker™ 480 and 680, that the clotting of plasma from type 2 diabetics is also amyloid in nature, and that this may be prevented by the addition of suitable concentrations of LPS-binding protein.. This implies strongly that there is indeed a microbial component to the development of type 2 diabetes, and suggests that LBP might be used as treatment for it and its sequelae.

Topics: Adolescent; Adult; Aged; Amyloid; Coloring Agents; Diabetes Mellitus, Type 2; Female; Fibrin; Fluorescent Dyes; Humans; Male; Middle Aged; Young Adult

Both type 2 diabetes (T2DM) and Bβ448Lys variant of fibrinogen are associated with dense fibrin clots, impaired fibrinolysis and increased cardiovascular risk. It was our objective to investigate whether BβArg448Lys adds to vascular risk by modulating fibrin network structure and/or fibrinolysis in diabetes. The primary aim was to study effects of BβArg448Lys on fibrin network characteristics in T2DM. Secondary aims investigated interactions between gender and BβArg448Lys substitution in relation to fibrin clot properties and vascular disease. Genotyping for BβArg448Lys and dynamic clot studies were carried out on 822 T2DM patients enrolled in the Edinburgh Type 2 Diabetes Study. Turbidimetric assays of individual plasma samples analysed fibrin clot characteristics with additional experiments conducted on clots made from purified fibrinogen, further examined by confocal and electron microscopy. Plasma clot lysis time in Bβ448Lys was longer than Bβ448Arg variant (mean ± SD; 763 ± 322 and 719 ± 351 seconds [s], respectively; p<0.05). Clots made from plasma-purified fibrinogen of individuals with Arg/Arg, Arg/Lys and Lys/Lys genotypes showed differences in fibre thickness (46.75 ± 8.07, 38.40 ± 6.04 and 25 ± 4.99 nm, respectively; p<0.001) and clot lysis time (419 ± 64, 442 ± 87 and 517 ± 65 s, respectively; p=0.02), directly implicating the polymorphism in the observed changes. Women with Bβ448Lys genotype had increased risk of cerebrovascular events and were younger compared with Bβ448Arg variant (67.2 ± 4.0 and 68.2 ± 4.4 years, respectively; p=0.035). In conclusion, fibrinogen Bβ448Lys variant is associated with thrombotic fibrin clots in diabetes independently of traditional risk factors. Prospective studies are warranted to fully understand the role of BβArg448Lys in predisposition to vascular ischaemia in T2DM with the potential to develop individualised antithrombotic management strategies.

Topics: Aged; Blood Coagulation Tests; Diabetes Mellitus, Type 2; Female; Fibrin; Fibrinogen; Fibrinolysis; Genetic Association Studies; Genotype; Humans; Male; Microscopy, Electron, Scanning; Middle Aged; Phenotype; Polymorphism, Genetic; Protein Conformation; Risk Assessment; Risk Factors; Scotland; Structure-Activity Relationship; Thrombosis

Topics: Diabetes Mellitus, Type 2; Diabetic Retinopathy; Eye Diseases; Fibrin; Humans; Laser Coagulation; Macular Edema; Male; Middle Aged; Postoperative Complications; Tomography, Optical Coherence; Vitrectomy; Vitreous Body; Vitreous Hemorrhage

We investigated whether and to what extent the ratio between circulating fibrinogen (Fg) and its degradation products (FDP) reflects the severity of coronary artery disease (CAD) in type 2 diabetic patients.. Plasma levels of Fg and FDP were determined, and Fg/FDP ratio was calculated in 344 consecutive patients with type 2 diabetes and chest pain on exertion undergoing coronary angiography. The severity of CAD was evaluated by the number of significant CAD (>50% luminal diameter narrowing) and Gensini score.. Plasma Fg was higher, but Fg/FDP ratio was lower in patients with significant CAD (n = 255) compared with those without (n = 89), due to a disproportionate increase in FDP. Fg and FDP correlated positively, while Fg/FDP ratio negatively, with the number of diseased coronary arteries and the tertile of Gensini score (all P values for trend < 0.01). After adjusting for age, sex, risk factors for CAD, lipid profiles, glycosylated hemoglobin A1c, creatinine, leukocyte count, and high-sensitivity C-reactive protein, Fg/FDP ratio remained an independent determinant for multivessel coronary disease (MVD) (odds ratio [OR], 0.869; 95% confidence interval [CI], 0.788-0.958, P = 0.005) and high tertile of Gensini score (OR, 0.797, 95% CI, 0.682-0.930, P = 0.004). The area under the curve of Fg/FDP ratio was larger than that of Fg for predicting the presence of MVD (0.647 vs. 0.563, P = 0.048) and Gensini score ≥ 30 (0.656 vs. 0.538, P = 0.026).. Elevated plasma Fg and FDP level and reduced Fg/FDP ratio are associated with presence of CAD, and Fg/FDP ratio is superior to Fg in reflecting severe coronary atherosclerosis for patients with type 2 diabetes.

Topics: Aged; Coronary Angiography; Coronary Artery Disease; Diabetes Mellitus, Type 2; Female; Fibrin; Fibrinogen; Humans; Male; Middle Aged

To investigate the effect of low blood glucose on thrombin generation and fibrin clot properties in type 2 diabetes (T2DM).. In 165 patients with T2DM and high cardiovascular risk, we measured ex vivo plasma fibrin clot permeation [Ks], turbidity and efficiency of fibrinolysis including clot lysis time [t50%], together with thrombin generation and platelet activation markers in relation to fasting blood glucose.. As compared to patients in medium (4.5-6.0 mmol/l, n = 52) and higher (>6.0 mmol/l, n = 75) glucose group, subjects with low glycemia (<4.5 mmol/l, n = 38) had lower Ks by 11% (p < 0.001) and 8% (p = 0.01), respectively, prolonged t50% by 10% (p < 0.001) and 7% (p = 0.016), respectively, and higher peak thrombin generation by 21% and 16%, respectively (p < 0.001 for both). There were no significant differences in Ks and t50% between patients in medium and higher glucose group. In the whole group, a J-shape relationship was observed between glycemia and the following factors: peak thrombin generation, Ks and t50%. Only in patients with HbA1c < 6.0% (42 mmol/mol) (n = 26) fasting glucose positively correlated with Ks (r = 0.53, P = 0.006) and inversely with t50% (r = -0.46, P = 0.02). By multiple regression analysis, after adjustment for age, fibrinogen, HbA1c, insulin treatment and T2DM duration, fasting glycemia was the independent predictor of Ks (F = 6.6, df = 2, P = 0.002), t50% (F = 8.0, df = 2, P < 0.001) and peak thrombin generation (F = 13.5, df = 2, P < 0.0001).. In T2DM patients fasting glycemia <4.5 mmol/l is associated with enhanced thrombin formation and formation of denser fibrin clots displaying lower lysability, especially when strict glycemia control was achieved (HbA1c<6.0%).

Topics: Aged; Blood Coagulation; Blood Glucose; Cardiovascular Diseases; Diabetes Mellitus, Type 2; Fasting; Female; Fibrin; Humans; Male; Middle Aged; Risk Factors; Thrombin

We sought to investigate whether enhanced oxidation contributes to unfavorable fibrin clot properties in patients with diabetes.. We assessed plasma fibrin clot permeation (K s , a measure of the pore size in fibrin networks) and clot lysis time induced by recombinant tissue plasminogen activator (CLT) in 163 consecutive type 2 diabetic patients (92 men and 71 women) aged 65 ± 8.8 years with a mean glycated hemoglobin (HbA1c) of 6.8%. We also measured oxidative stress markers, including nitrotyrosine, the soluble form of receptor for advanced glycation end products (sRAGE), 8-iso-prostaglandin F2α (8-iso-PGF2α ), oxidized low-density lipoprotein (oxLDL), and advanced glycation end products (AGE).. There were inverse correlations between K s and nitrotyrosine, sRAGE, 8-iso-PGF2α , and oxLDL. CLT showed a positive correlation with oxLDL and nitrotyrosine but not with other oxidation markers. All these associations remained significant for K s after adjustment for fibrinogen, disease duration, and HbA1c (all P < 0.05), while oxLDL was the only independent predictor of CLT.. Our study shows that enhanced oxidative stress adversely affects plasma fibrin clot properties in type 2 diabetic patients, regardless of disease duration and glycemia control.

Topics: Aged; Aged, 80 and over; Blood Coagulation; Blood Glucose; Diabetes Mellitus, Type 2; Dinoprost; Female; Fibrin; Fibrinolysis; Glomerular Filtration Rate; Glycated Hemoglobin; Glycation End Products, Advanced; Humans; Kinetics; Lipoproteins, LDL; Male; Middle Aged; Oxidative Stress; Oxygen; Permeability; Receptor for Advanced Glycation End Products; Recombinant Proteins; Surveys and Questionnaires; Tissue Plasminogen Activator; Tyrosine

It has been shown that type 2 diabetes (DM) is associated with enhanced thrombin generation and formation of denser fibrin clots of reduced lysability. We sought to investigate the impact of diabetes duration versus glycaemia control on fibrin clot phenotype and its determinants in type 2 diabetic patients. In 156 consecutive Caucasian patients with type 2 diabetes we investigated ex vivo thrombin generation, fibrinolytic proteins, along with plasma fibrin clot permeation (Ks), compaction, turbidity, and efficiency of tissue plasminogen activator (t-PA)-mediated fibrinolysis. Patients with longer diabetes duration (>5 years, median; n=68) had higher peak thrombin generation (+16.3%, p<0.001), plasminogen activator inhibitor-1 (PAI-1) antigen (+14.8%, p=0.001), t-PA antigen (+13.9%, p=0.002) compared with those with duration ≤5 years (n=88). No such differences were observed between patients with inadequate glycaemic control, defined as glycated haemoglobin (HbA1C) >6.5% (48 mmol/mol) (n=77), versus those with HbA1C≤6.5% (n=79). Fibrinogen, thrombin-activatable fibrinolysis inhibitor antigen, plasminogen and soluble thrombomodulin were unaffected by disease duration or glycaemia control. Lower clot permeability, longer clot lysis, and higher maximum D-dimer levels released from clots (all p<0.05 after adjustment for fibrinogen, age, body mass index, insulin, acetylsalicylic acid treatment, and HbA1c or diabetes duration) were also observed in patients with diabetes duration >5 years and those with HbA1C>6.5%. We conclude that prolonged duration of type 2 diabetes is associated with increased thrombin formation, hypofibrinolysis, and prothrombotic fibrin clot phenotype. The impact of disease duration on coagulation is different and stronger than that observed during inadequate glycaemia control.

Topics: Aged; Blood Coagulation; Diabetes Mellitus, Type 2; Disease Progression; Female; Fibrin; Fibrin Clot Lysis Time; Fibrin Fibrinogen Degradation Products; Fibrinolysis; Humans; Phenotype; Plasminogen Activator Inhibitor 1; Thrombin; Time Factors

Type 2 diabetes mellitus (T2DM) increases the risk of coronary thrombosis and both conditions are associated with altered fibrin clot properties. However, the influence of T2DM on fibrin clot properties in patients with coronary artery disease (CAD) remains unclear. We aimed to investigate the influence of T2DM on fibrin clot properties in patients with CAD. Fibrin clot structure and fibrinolysis were investigated in 581 CAD patients (148 with T2DM) using turbidimetric assays, confocal and scanning electron microscopy. Clots made from plasma and plasma-purified fibrinogen were studied, and plasma levels of inflammatory markers were analysed. T2DM patients had increased clot maximum absorbance compared with non-diabetic patients (0.36 ± 0.1 vs 0.33 ± 0.1 au; p=0.01), displayed longer lysis time (804 [618;1002] vs 750 [624;906] seconds; p=0.03) and showed more compact fibrin structure assessed by confocal and electron microscopy. Fibrinogen levels were elevated in T2DM (p< 0.001), but clots made from purified fibrinogen showed no differences in fibrin properties in the two populations. Adjusting for fibrinogen levels, T2DM was associated with C-reactive protein and complement C3 plasma levels, with the former correlating with clot maximum absorbance (r=0.24, p< 0.0001) and the latter with lysis time (r=0.30, p< 0.0001). Independent of fibrinogen levels, females had more compact clots with prolonged lysis time compared with males (all p-values< 0.001). In conclusion, T2DM is associated with prothrombotic changes in fibrin clot properties in patients with CAD. This is related to quantitative rather than qualitative changes in fibrinogen with a possible role for inflammatory proteins.

Topics: Aged; Aspirin; Blood Coagulation Tests; C-Reactive Protein; Case-Control Studies; Complement C3; Coronary Artery Disease; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Female; Fibrin; Fibrinogen; Fibrinolysis; Humans; Inflammation Mediators; Male; Microscopy, Confocal; Microscopy, Electron, Scanning; Middle Aged; Nephelometry and Turbidimetry; Platelet Aggregation Inhibitors; Registries; Risk Factors; Sex Factors; Time Factors

Serum albumin is an essential plasma protein that serves an important function in maintaining osmotic pressure. Low levels of this protein are associated with the kidney failure and hemodialysis that are often seen in diabetic patients who are at high risk of thrombotic events. In diabetes, fibrin fiber nets are changed to form dense matted deposits (DMDs, or parafibrin). Here the authors investigate whether parafibrin is also present in diagnosed low-albumin diabetes patients and whether the addition of human albumin to plasma from low-albumin diabetes type 2 individuals may change the architecture of the fibrin nets. The authors show that the addition of albumin to plasma of low-albumin diabetes patients progressively caused the DMDs typically found in these patients to revert back to ultrastructure typically seen in healthy individuals. This disease has an extremely complicated pathophysiology and thus cannot be considered as a simple condition. This study shows that serum albumin levels may play an important role in the structure of fibrin fibrils, making them more susceptible to the fibrinolytic degradation and elimination from the circulation.

Topics: Diabetes Mellitus, Type 2; Fibrin; Humans; Microscopy, Electron, Scanning; Serum Albumin

Altered fibrin clot structure has been reported both in patients with coronary artery disease (CAD) and those with type 2 diabetes mellitus (DM2). The aim of the present study was to evaluate plasma fibrin clot permeability and susceptibility to lysis in patients with DM2 and CAD. We studied 132 consecutive CAD patients, including 67 subjects with DM2, scheduled for elective coronary artery bypass grafting surgery. Ex vivo plasma fibrin clot permeability (K(s)) and lysis time (t(50%)) induced by 1 μg/mL recombinant tissue plasminogen activator (tPA), along with plasma levels of plasminogen activator inhibitor-1 (PAI-1), thrombin activatable fibrinolysis inhibitor (TAFI), tPA, von Willebrand factor (vWF), P-selectin, soluble CD40 ligand (sCD40L), were measured. Diabetic and non-diabetic patients did not differ in regard to demographics and remaining cardiovascular risk factors. Concomitant DM2 was associated with higher glucose (+24.3%, p < 0.001), fibrinogen (+9.0%, p = 0.037), PAI-1 (+58.7%, p < 0.001), tPA (+24.0%, p < 0.001) and P-selectin (+12.2%, p < 0.001). Compared with the non-diabetic group, the CAD patients with DM2 had lower K(s) (-6.1%, p = 0.02) and prolonged t(50%) (+5.1%, p = 0.04). Multiple regression analysis of the whole study group showed that vWF, PAI-1, fibrinogen and DM2 were the independent predictors of t(50%) (R(2) = 0.58, p < 0.001), while only vWF was an independent predictor of K(s) (R(2) = 0.22, p < 0.001). This study indicates that DM2 is potent enough to unfavorably affect plasma fibrin clot characteristics despite abnormal clot phenotype typically observed in CAD. Of note, platelet and endothelial markers appear to contribute to fibrin clot properties in CAD concomitant with DM2.

Topics: Aged; Case-Control Studies; Coronary Artery Disease; Diabetes Mellitus, Type 2; Female; Fibrin; Humans; Male; Middle Aged

The development and progression of diabetic retinopathy (DR) in type 2 diabetes mellitus (T2DM) have been associated with poor glycaemic control, long disease duration and other clinical features. However, the pathogenesis of the complication is still poorly understood. As the formation of dense fibrin clots resistant to lysis has been described in diabetes patients, this study tested the hypothesis that altered clot structure and function are associated with DR in T2DM patients.. The study included 101 T2DM subjects without DR (NDR) and 60 with DR. Plasma fibrin-clot permeation was assessed using a pressure-driven system, and expressed as the permeation coefficient (K(s)), indicating pore size, and as the time required for a 50% decrease in clot turbidity (t(50%)) as a marker of susceptibility to fibrinolysis. All patients underwent ophthalmological examination. Clinical and biochemical co-variables were also measured. Determinants of DR were identified using stepwise, multivariable, logistic-regression analyses.. Patients with DR had lower clot permeability (K(s): 6.15 ± 1.18 vs. 7.53 ± 1.24 10(-9) cm(2); P < 0.0001) and slower fibrin-clot lysis (t(50%): 10.12 ± 1.24 vs. 9.12 ± 1.4 min; P < 0.0001) than NDR subjects. Logistic analysis revealed associations between DR and K(s), t(50%), fasting glucose and diabetes duration, as well as insulin treatment and statin non-use (P < 0.05). After adjusting for these variables as well as for age and gender, associations between K(s) and t(50%) with DR proved to be significant.. Formation of compact fibrin clots and impaired clot lysis are both associated with DR in T2DM patients. However, it is unclear whether these abnormalities lead to the development of DR or merely constitute a marker of its presence.

Topics: Biomarkers; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Diabetic Retinopathy; Female; Fibrin; Humans; Male; Middle Aged; Risk Factors

Diabetes is associated with increased incidence of atherothrombotic disease. The fibrin network forms the backbone of the arterial thrombus, and fibrin clot structure determines predisposition to cardiovascular events.. The aim of the study was to investigate fibrin clot structure/fibrinolysis in the largest type 2 diabetes cohort and analyze associations with cardiometabolic risk factors and vascular pathology.. Clot structure/fibrinolysis was assessed in 875 participants of the Edinburgh Type 2 Diabetes Study [age, 68 (range, 60-75) yr; 450 males] by turbidimetric assays, and clots were visualized by confocal microscopy. Four parameters of clot structure/fibrinolysis were analyzed, and plasma levels of fibrinogen and plasminogen activator inhibitor-1 were studied by Clauss assay and ELISA, respectively.. Clot maximum absorbance was increased in females compared with males (0.37 ± 0.005 and 0.34 ± 0.005 arbitrary unit, respectively; P < 0.001), and took longer to lyse (803 ± 20 and 665 ± 12 sec, respectively; P < 0.001). These gender differences in clot structure and fibrinolysis were still evident after correcting for fibrinogen and plasminogen activator inhibitor-1 plasma levels. A prothrombotic fibrin structure profile was associated with increased body mass index and low levels of high-density lipoprotein in women and with inadequate diabetes control in men. Clot formation time was related to previous cardiac ischemic events in both men and women after adjusting for traditional risk factors [odds ratio, 1.22 (95% confidence interval, 1.07, 1.38); and 1.33 (1.15, 1.50), respectively], and prothrombotic clots were associated with low ankle brachial index, renal impairment, and smoking, regardless of gender.. Women with type 2 diabetes have compact clots with compromised fibrinolysis compared with men. There are gender-specific associations between clotting parameters and cardiometabolic risk factors in this population, whereas vascular abnormalities, impaired renal function, and smoking are associated with prothrombotic clot structure profile regardless of gender.

Topics: Aged; Biomarkers; Blood Coagulation; Blood Coagulation Tests; Cardiovascular Diseases; Cohort Studies; Diabetes Mellitus, Type 2; Female; Fibrin; Fibrinolysis; Humans; Male; Metabolic Diseases; Middle Aged; Risk Factors; Sex Factors; Structure-Activity Relationship

Type 2 diabetes is an important risk factor for the development of coronary artery disease (CAD). Focal or diffuse inflammation is often present in the vessels of patients with CAD. Mast cells are frequently present in the plaques as well as in the inflammatory infiltrates in the atherosclerotic vessel wall. In the study we wanted to examine whether there are differences in the morphology, number and distribution of mast cells and in their ability to modify the atherosclerotic process in coronary arteries (CA) in the diabetic vs. the hypertensive population of patients with CAD.. Coronary artery endarterectomy specimens were obtained from patients with diabetes or hypertension as the only risk factor for CAD. The specimens were stained with haematoxylin-eosin and Sulphated Alcian Blue for mast cells and with immunofluorescent methods for fibrinogen-fibrin and IgG deposits in the vessel wall. Both morphological and stereological assessments were conducted for mast cells and mononuclear cell infiltrates.. The histological analysis of the vessel wall of diabetic patients in comparison with hypertensive patients showed a damaged endothelial cells layer and deposits of fibrin-fibrinogen and IgG in the tunica intima and media. The stereological count revealed a diminished numerical density of mast cells and a significantly higher volume density of the mononuclear cells. Mast cells displayed cytoplasmic vacuolization, extracellular extrusion of granule and pyknotic nuclei.. This preliminary study suggests that the impaired mast cells might be the reason for more extensive inflammatory and immunologic atherosclerotic changes in the CA vessel wall of CAD patients with type 2 diabetes.

Topics: Aged; Coronary Artery Bypass; Coronary Artery Disease; Coronary Vessels; Diabetes Mellitus, Type 2; Endarterectomy; Fibrin; Fibrinogen; Fluorescent Antibody Technique; Humans; Hypertension; Immunoglobulin G; Male; Mast Cells; Middle Aged; Pilot Projects; Slovenia; Staining and Labeling

The active type of coagulation factor X (factor Xa) activates various cell-types through protease-activated receptor 2 (PAR2). We previously reported that a factor Xa inhibitor could suppress Thy-1 nephritis. Considering that fibrin deposition is observed in diabetic nephropathy as well as in glomerulonephritis, this study examined the roles of the coagulation pathway and factor Xa in the development of diabetic nephropathy using type 2 diabetic model mice. Diabetic (db/db) and normoglycemic (m+/m+) mice were immunohistochemically evaluated for their expression/deposition of PAR2, transforming growth factor (TGF)-β, fibrin, extracellular matrix (ECM) proteins, and CD31 at week 20. Significantly greater numbers of PAR2-positive cells and larger amounts of fibronectin, and collagen IV depositions were observed in the glomeruli of db/db mice than those in m+/m+ mice. Next, expression of PAR2 versus deposition of collagen IV and fibronectin was compared between week 20 and week 30, and the number of PAR2-positive cells in the glomeruli decreased in contrast with the increased accumulation of ECM proteins. In an intervention study, fondaparinux, a factor Xa inhibitor, was subcutaneously administered for ten weeks from week 10 to 20. Fondaparinux treatment significantly suppressed urinary protein, glomerular hypertrophy, fibrin deposition, expression of connective tissue growth factor, and ECM proteins deposition together with CD31-positive capillaries. These results suggest that coagulation pathway and glomerular PAR2 expression are upregulated in the early phase of diabetes, together with the increase of profibrotic cytokines expression, ECM proteins deposition and CD-31-positive vessels. Factor Xa inhibition may ameliorate glomerular neoangiogenesis and ECM accumulation in diabetic nephropathy.

Topics: Animals; Anticoagulants; Blood Coagulation; Capillaries; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Disease Progression; Extracellular Matrix Proteins; Factor Xa; Factor Xa Inhibitors; Fibrin; Fondaparinux; Hypertrophy; Kidney; Kidney Glomerulus; Male; Mice; Mice, Obese; Platelet Endothelial Cell Adhesion Molecule-1; Polysaccharides; Proteinuria; Receptor, PAR-2; Transforming Growth Factor beta; Up-Regulation

Individuals with hypertension, dyslipidemia or diabetes are at a higher risk to suffer cardiovascular disease than other people; while impaired fibrin structure/function may contribute to further raise the cardiovascular risk in the former. The purpose of this work was to study the fibrin network and fibrin degradation properties in hypertensive (HT) patients, pharmacologically treated, 124 +/- 11 mmHg, systolic blood pressure, and 70 +/- 10 mmHg, diastolic blood pressure, n = 12; metabolic dyslipidemic patients (DL), cholesterol: 5.7 +/- 1.5 mmol/L, n = 10; patients with type 2 diabetes mellitus (T2D), fasting plasma glucose: 8.8 +/- 2.2 mmol/L, n = 10; and a control group of healthy individuals, n = 9. The fibrinogen concentration was determined by the gravimetric method. Fibrin network formation and porosity were assessed by turbidity and permeation techniques, respectively; fibrin elastic properties were evaluated by compaction and fibrin lysis, by turbidity after addition of external tPA prior to plasma clotting. Fibrinogen concentration was significantly higher only in T2D patients (p = 0.004), compared to the control group. The fibrin polymerization and lysis processes were similar for all patient and control groups. Permeation was significantly slower in DL and T2D patients, p = 0.022 and 0.0002, respectively, whereas the compaction coefficient was significantly smaller in T2D patients, p = 0.0015. Our results suggest that the fibrin structure was altered in DL and T2D patients, probably due to the increased cholesterol and glycation, respectively.

Topics: Diabetes Mellitus, Type 2; Dyslipidemias; Female; Fibrin; Humans; Hypertension; Male; Middle Aged; Structure-Activity Relationship

Topics: Aged; Angiotensin-Converting Enzyme Inhibitors; Aspirin; Coronary Disease; Diabetes Mellitus, Type 2; Female; Fibrin; Humans; Hypertension; Middle Aged; Platelet Aggregation

Diabetic subjects have been shown to have altered fibrin network structures. One proposed mechanism for this is non-enzymatic glycation of fibrinogen due to high blood glucose. We investigated whether glycaemic control would result in altered fibrin network structures due to decreased fibrinogen glycation. Twenty uncontrolled type 2 diabetic subjects were treated with insulin in order to achieve glycaemic control. Twenty age- and body mass index (BMI)-matched non-diabetic subjects were included as a reference group. Purified fibrinogen, isolated from plasma samples was used for analysis. There was a significant decrease in fibrinogen glycation (6.81 to 5.02 mol glucose/mol fibrinogen) with a corresponding decrease in rate of lateral aggregation (5.86 to 4.62) and increased permeability (2.45 to 2.85 x 10(-8) cm(2)) and lysis rate (3.08 to 3.27 microm/min) in the diabetic subjects after glycaemic control. These variables correlated with markers of glycaemic control. Fibrin clots of non-diabetic subjects had a significantly higher ratio of inelastic to elastic deformation than the diabetic subjects (0.10 vs. 0.09). Although there was no difference in median fiber diameter between diabetic and non-diabetic subjects, there was a small increase in the proportion of thicker fibers in the diabetic samples after glycaemic control. Results from SDS-PAGE indicated no detectable difference in factor XIIIa-crosslinking of fibrin clots between uncontrolled and controlled diabetic samples. Diabetic subjects may have altered fibrin network formation kinetics which contributes to decreased pore size and lysis rate of fibrin clots. Achievement of glycaemic control and decreased fibrinogen glycation level improves permeability and lysis rates in a purified fibrinogen model.

Topics: Adult; Aged; Blood Glucose; Case-Control Studies; Cross-Linking Reagents; Diabetes Mellitus, Type 2; Elasticity; Factor XIIIa; Female; Fibrin; Fibrinogen; Fibrinolysis; Glycosylation; Humans; Hypoglycemic Agents; Insulin; Male; Microscopy, Confocal; Microscopy, Electron, Scanning; Middle Aged; Models, Biological

Acute hyperglycemia on admission for acute coronary syndrome worsens the prognosis in patients with and without known diabetes. Postulated mechanisms of this observation include prothrombotic effects. The aim of this study was to evaluate the effect of elevated glucose levels on blood clotting in acute coronary syndrome patients.. We studied 60 acute coronary syndrome patients within the first 12 h after pain onset, including 20 subjects with type 2 diabetes, 20 subjects with no diagnosed diabetes but with glucose levels >7.0 mmol/l, and 20 subjects with glucose levels <7.0 mmol/l. We determined generation of thrombin-antithrombin complexes (TATs) and soluble CD40 ligand (sCD40L), a platelet activation marker, at the site of microvascular injury, together with ex vivo plasma fibrin clot permeability and lysis time.. The acute coronary syndrome patients with no prior diabetes but elevated glucose levels had increased maximum rates of formation and total production of TATs (by 42.9%, P < 0.0001, and by 25%, P < 0.0001, respectively) as well as sCD40L release (by 16.2%, P = 0.0011, and by 16.3%, P < 0.0001, respectively) compared with those with normoglycemia, whereas diabetic patients had the highest values of TATs and sCD40L variables (P < 0.0001 for all comparisons). Patients with hyperglycemia, with no previously diagnosed diabetes, had longer clot lysis time (by approximately 18%, P < 0.0001) similar to that in diabetic subjects, but not lower clot permeability compared with that in normoglycemic subjects.. Hyperglycemia in acute coronary syndrome is associated with enhanced local thrombin generation and platelet activation, as well as unfavorably altered clot features in patients with and without a previous history of diabetes.

Topics: Acute Coronary Syndrome; Acute Disease; Aged; Blood Coagulation; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Female; Fibrin; Fibrinolysis; Humans; Hyperglycemia; Hypoglycemic Agents; Male; Middle Aged; Myocardial Infarction; Platelet Activation; Prognosis; Thrombin

The aim of this study was to determine the influence of type 2 diabetes on fibrinolysis by assessing interactions between the regulatory components of fibrinolysis and the fibrin clot, using fibrinogen purified from 150 patients with type 2 diabetes and 50 matched controls.. Clot lysis rates were determined by confocal microscopy. Plasmin generation was measured using a plasmin-specific chromogenic substrate. Surface plasmon resonance was used to determine the binding interactions between fibrin, tissue-type plasminogen activator (t-PA) and Glu-plasminogen; cross-linkage of plasmin inhibitor to fibrin by factor XIII was determined using a microtitre plate assay.. Lysis of diabetic clots was significantly slower than that of controls (1.35 vs 2.92 microm/min, p<0.0001) and plasmin generation was significantly reduced. The equilibrium binding affinity between both t-PA and Glu-plasminogen and fibrin was reduced in diabetic subjects: t-PA, K (D)=0.91+/-0.3 micromol/l (control subjects), 1.21+/-0.5 micromol/l (diabetic subjects), p=0.001; Glu-plasminogen, K (D)=97+/-19 nmol/l (control subjects), 156+/-66 nmol/l (diabetic subjects), p=0.001. Cross-linkage of plasmin inhibitor to fibrin by factor XIII was enhanced in diabetic subjects, with the extent of in vitro cross-linkage correlating with in vivo glycaemic control (HbA(1c)) (r=0.59, p=0.001).. These results indicate that impairment of the fibrinolytic process in diabetic patients is mediated via a number of different mechanisms; these may be a consequence of post-translational modifications to fibrinogen molecules, resulting from their exposure to the abnormal metabolic milieu associated with diabetes.

Topics: Aged; Blood Glucose; Body Mass Index; Diabetes Mellitus, Type 2; Drug Resistance; Enzyme Activation; Factor XIII; Female; Fibrin; Fibrinogen; Fibrinolysin; Glycated Hemoglobin; Hemolysis; Humans; Male; Mass Spectrometry; Middle Aged; Reference Values; Surface Plasmon Resonance

The precise mechanisms underlying the increased risk of cardiovascular disease (CVD) in type 2 diabetes are unclear. Fibrin clot structure has been related to CVD risk in the general population. We therefore assessed this in type 2 diabetic patients as a potential mechanism whereby diabetes influences CVD risk.. Fibrin clots were formed from fibrinogen purified from 150 subjects with type 2 diabetes and varying degrees of glycaemic control (assessed by HbA1c), and from 50 matched control subjects. Clot structure was assessed by turbidity, permeation and confocal microscopy. The specific effect of glucose itself was assessed by analysing the structure of clots formed from purified fibrinogen in the presence of increasing concentrations of the sugar.. Clots formed by fibrinogen purified from type 2 diabetic subjects had a denser, less porous structure than those from control subjects. The structural changes found were related to the individual's glycaemic control; HbA1c correlated negatively with permeation coefficient (Ks) values (indicates clot pore size) (r = -0.57, p < 0.0001) and positively with maximum absorbance (indicator of fibre size) (r = 0.33, p < 0.0001), branch point number (r = 0.78, p < 0.0001) and fibre density (r = 0.63, p < 0.0001). The ambient glucose level influenced clot structure; hypo- (< 5 mmol) and hyperglycaemia (> or = 10 mmol/l) were both associated with a reduction in Ks values and maximum absorbance, and with increased fibre density and branch point number within clots.. The structural differences found to occur in type 2 diabetes and in association with hypo- and hyperglycaemia may confer increased resistance to fibrinolysis, and in consequence contribute to the increase in CVD risk in diabetic patients.

Topics: Blood Coagulation; Body Mass Index; Body Size; Cardiovascular Diseases; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Factor XIII; Female; Fibrin; Fibrinogen; Humans; Hypoglycemic Agents; Lipids; Male; Middle Aged; Reference Values; Risk Factors

Coronary remodeling based on collagen abnormalities in diabetes might be associated with potential interactions between the matrix metalloproteinase (MMP) system, which regulates extracellular matrix turnover, and the fibrinolytic system, which is involved in the fibrin degradation process. We characterized the profiles of the MMP and fibrinolytic systems in insulin-resistant diabetic rat hearts.. By immunohistochemistry and in situ hybridization, transforming growth factor-beta1 (TGF-beta1) expression increased in coronary vessels, the perivascular area, and cardiomyocytes in diabetic rat hearts. Increased expression of plasminogen activator inhibitor-1 (PAI-1) in coronary vessels and the perivascular area was evident in diabetic hearts. In contrast, diabetic hearts exhibited reduced activity and expression of MMP-2 and decreased expression of membrane type-1 MMP (MT1-MMP). Both intravascular and extravascular collagen type I and III immunoreactivity and fibrin deposition were seen in diabetic coronary vessels. These alterations were reversed to nondiabetic levels by the angiotensin II type 1 receptor blocker candesartan, which prevented the development of perivascular fibrosis observed after Masson's trichrome staining.. In addition to upregulation of PAI-1, downregulation of MMP-2 and MT1-MMP might play a crucial role in coronary matrix remodeling in insulin-resistant diabetes. These molecules appear to be regulated by angiotensin II via stimulation of TGF-beta1.

Topics: Angiotensin II; Animals; Collagen Type I; Collagen Type III; Coronary Vessels; Diabetes Mellitus, Type 2; Down-Regulation; Fibrin; Fibrosis; Insulin Resistance; Matrix Metalloproteinase 2; Matrix Metalloproteinases; Rats; Rats, Inbred OLETF; Receptor, Melatonin, MT1; Transforming Growth Factor beta

Collagen IV matrix of glomerular basement membrane may be involved in the development of various renal diseases, e.g. diabetic nephropathy. An immunoblotting method for the detection of the carboxy-terminal non-collagenous (NC1) domain of type IV collagen in plasma was developed. The high sensitivity down to the picogram range enabled characterization of NC1(IV) fragments in human blood for the first time. Both Western blotting and gel filtration chromatography coupled with an enzyme-linked immunoassay surprisingly revealed that the NC1(IV)-related components are bound to the fibrin clot forming during blood coagulation. About 40% of the NC1(IV) fragments in plasma had an apparent molecular mass higher than 340,000. Abnormal NC1(IV) immunoblot patterns were observed in about 50% of patients with insulin-dependent (n = 20) and non-insulin-dependent (n = 20) diabetes mellitus compared with less than 7% in healthy control subjects (n = 30). There were no obvious associations between abnormal immunoblots and stage of nephropathy or glycaemic control in diabetic subjects.

Topics: Adult; Aged; Antibodies; Antigens; Binding, Competitive; Blood Coagulation; Blood Glucose; Blotting, Western; Chromatography, Gel; Collagen; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Electrophoresis, Polyacrylamide Gel; Enzyme-Linked Immunosorbent Assay; Female; Fibrin; Humans; Male; Middle Aged; Protein Structure, Tertiary; Sensitivity and Specificity

We measured the plasma levels of fibrinogen, D-dimer, thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), soluble fibrin monomer (SFM), tissue-type plasminogen activator (t-PA) and thrombomodulin (TM) in patients with non-insulin-dependent diabetes mellitus (NIDDM). There were no significant differences in the hemostatic parameters between the 77 patients with NIDDM and healthy control subjects, although the plasma levels of fibrinogen, D-dimer, TAT, and PPIC in the NIDDM patients were slightly higher than those in the healthy controls. Among the NIDDM patients divided into three groups by the urinary albumin excretion (UAE) level, there was no significant difference in age or sex among the normo-, micro-, and macroalbuminuria groups, and the HbA1C level in the micro- and macroalbuminuria groups were slightly higher than those in the normoalbuminuria group. There was no significant difference in activated partial thromboplastin time, prothrombin time, fibrinogen, TAT, PPIC, D-dimer, or t-PA among these three groups. The plasma SFM and TM levels in the macroalbuminuria group were significantly higher than those in the normo- and microalbuminuria groups. The relationships between HbA1C and the hemostatic parameters were poor, but the plasma TM and SFM levels were significantly correlated with the urine albumin index.

Topics: Adult; Aged; Albuminuria; Diabetes Mellitus, Type 2; Female; Fibrin; Humans; Male; Middle Aged; Prothrombin Time; Thrombomodulin

We evaluated thrombin-induced inositol phosphate accumulation in [3H]inositol-labeled platelets prepared from patients with non-insulin-dependent diabetes mellitus. There were no significant differences in [3H]inositol incorporation into and contents of phosphoinositides between the diabetic patients and their age-matched control subjects. Thrombin induced a dose- and time-dependent accumulation of inositol phosphate. The accumulation of [3H]inositol trisphosphate and [3H]inositol bisphosphate by thrombin stimulation were significantly enhanced in platelets from the diabetic patients, although the accumulation of [3H]inositol monophosphate did not differ between the diabetic patients and the control subjects. In addition, the platelet aggregation rate induced by thrombin was also significantly enhanced in the diabetic patients in correlation with the enhanced inositol phosphate accumulation. These results suggest that increased inositol phosphate accumulation may cause accelerated platelet functions in diabetes mellitus.

Topics: Blood Platelets; Cholesterol; Diabetes Mellitus, Type 2; Female; Fibrin; Glycated Hemoglobin; Humans; In Vitro Techniques; Inositol; Inositol Phosphates; Kinetics; Male; Middle Aged; Phosphatidylinositols; Platelet Aggregation; Reference Values; Triglycerides; Tritium