Red blood cells (RBCs) are the most abundant cell type in the human body. RBCs and, in particular, their plasma membrane composition have been extensively studied for many years. During the past decade proteomics studies have extended our knowledge on RBC composition; however, these studies did not provide quantitative insights. Here we report a large-scale proteomics investigation of RBCs and their "white ghost" membrane fraction. Samples were processed using the multienzyme digestion filter-aided sample preparation (MED-FASP) and analyzed using Q-Exactive mass spectrometer. Protein abundances were computed using the total protein approach (TPA). The validation of the data with stable isotope-labeled peptide-based protein quantification followed. Our in-depth analysis resulted in the identification of 2650 proteins, of which 1890 occurred at more than 100 copies per cell. We quantified 41 membrane transporter proteins spanning an abundance range of five orders of magnitude. Some of these, including the drug transporter ABCA7 and choline transporters SLC44A1 and SLC44A2, have not previously been identified in RBC membranes. Comparison of protein copy numbers assessed by proteomics showed a good correlation with literature data; however, abundances of several proteins were not consistent with the classical references. Because we validated our findings by a targeted analysis using labeled standards, our data suggest that some older reference data from a variety of biochemical approaches are inaccurate. Our study provides the first "in-depth" quantitative analysis of the RBC proteome and will promote future studies of erythrocyte structure, functions, and disease.
The knowledge of arrhythmia and anticoagulation is better regarding the safety issues among subjects on NOACs compared with those on VKAs. Irrespective of the type of oral anticoagulation therapy, education of AF patients should be improved.
Background Type 2 diabetes mellitus (T2DM) is associated with a hypercoagulable state and increased neutrophil extracellular traps formation (NETosis). We investigated predictors of NETosis and cell death markers in circulating blood and their association with a prothrombotic state in T2DM. Methods In a cross-sectional study involving 113 T2DM patients aged 63.7 ± 8.2 years, we investigated citrullinated histone H3 (H3Cit), cell-free deoxyribonucleic acid (cfDNA), myeloperoxidase, neutrophil elastase, and inflammation markers, along with thrombin generation (TG), plasma clot lysis time (CLT), clot permeability (K s ) and fibrinolysis inhibitors. Results On multivariate logistic regression analysis adjusted for age and gender, predictors of high H3Cit (≥ 7.36 ng/mL, upper quartile) were: glycated hemoglobin (HbA1c) ≥ 7.0% and interleukin-6. Interleukin-6 was also found to be a predictor of high cfDNA (≥ 2.84 µg/mL, upper quartile) along with glucose. Citrullinated histone H3 and cfDNA correlated positively with CLT and inversely with K s , while TG associated solely with cfDNA. These associations were not seen with myeloperoxidase and neutrophil elastase. Patients with previous myocardial infarction (n = 21, 18.6%) had higher H3Cit (+108%, p < 0.001) and cfDNA (+45%, p = 0.022). On multivariable analysis adjusted for potential confounders, H3Cit and cfDNA, along with plasminogen activator inhibitor-1 and concomitant cardiovascular disease, were predictors of CLT. Citrullinated histone H3 alone was a predictor of K s and only cfDNA was a predictor of peak thrombin generated. Conclusions In T2DM, NETosis detectable in circulating blood is associated with inflammatory state and a prothrombotic state, especially hypofibrinolysis.
Depression is associated with an altered immune response, which could be normalized by antidepressant drugs. However, little is known about the influence of antidepressants on the peripheral immune response and function of macrophages in individuals not suffering from depression. Our studies were aimed at determining the influence of antidepressant drugs on the humoral and cellular immune response in mice. Mice were treated intraperitoneally with imipramine, fluoxetine, venlafaxine, or moclobemide and contact immunized with trinitrophenyl hapten followed by elicitation and measurement of contact sensitivity by ear swelling response. Peritoneal macrophages from drug-treated mice were either pulsed with sheep erythrocytes or conjugated with trinitrophenyl and transferred into naive recipients to induce humoral or contact sensitivity response, respectively. Secretion of reactive oxygen intermediates, nitric oxide, and cytokines by macrophages from drug-treated mice was assessed, respectively, in chemiluminometry, Griess-based colorimetry and enzyme-linked immunosorbent assay, and the expression of macrophage surface markers was analyzed cytometrically. Treatment of mice with fluoxetine, venlafaxine, and moclobemide results in suppression of humoral and cell-mediated immunity with a reduction of the release of macrophage proinflammatory mediators and the expression of antigen-presentation markers. In contrast, treatment with imipramine enhanced the humoral immune response and macrophage secretory activity but slightly suppressed active contact sensitivity. Our studies demonstrated that systemically delivered antidepressant drugs modulate the peripheral humoral and cell-mediated immune responses, mostly through their action on macrophages. Imipramine was rather proinflammatory, whereas other tested drugs expressed immunosuppressive potential. Current observations may be applied to new therapeutic strategies dedicated to various disorders associated with excessive inflammation.
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.
Objective We investigated clinical and laboratory determinants of plasma protein oxidation and its associations with clot fibrinolysis in type 2 diabetes patients. Materials and Methods Our cross-sectional study consisted of 246 type 2 diabetic patients, 143 (58%) with concomitant cardiovascular disease (CVD), including 41 (17%) with previous myocardial infarction (MI). We measured total protein carbonylation (PC), thiobarbituric acid reactive substances (TBARS) and total antioxidant capacity (TAC) along with clot lysis time (CLT) and clot permeation (Ks ), fibrinogen, plasminogen, α-2-antiplasmin, plasminogen activator inhibitor-1 (PAI-1), thrombin activatable fibrinolysis inhibitor (TAFI) and thrombomodulin. Results Total PC correlated positively, while TAC correlated inversely with glycated haemoglobin and diabetes duration (all p < 0.05). Diabetic patients with CVD had higher total PC, TBARS and lower TAC compared with the remainder (all p < 0.001). Among correlations of total PC with Ks , PAI-1, thrombomodulin and TAFI, the strongest was with CLT (r = 0.687, all p < 0.01). High total PC, defined as ≥ 3.45 nmol/mg, was predicted by time since diabetes diagnosis ≥ 5 years (odds ratio [OR]: 3.0, 95% confidence interval [CI]: 1.36–6.63) and previous MI (OR: 11.31, 95% CI: 4.37–29.32). After adjustment for potential confounders, total PC accounted for 34.9% of the total variance in CLT. Total PC at a cut-off of 3.44 nmol/mg showed high discriminatory power for identifying patients with prolonged CLT (area under the curve: 0.845, 95% CI: 0.792–0.898, p < 0.001). Conclusion Elevated plasma PC, largely driven by a long history of diabetes and concomitant CVD, is an important determinant of hypofibrinolysis in type 2 diabetes.
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