RESUMEN
Curcumae Radix (CR) is a widely used traditional Chinese medicine with significant pharmaceutical importance, including enhancing blood circulation and addressing blood stasis. This study aims to establish an integrated and rapid quality assessment method for CR from various botanical origins, based on chemical components, antiplatelet aggregation effects, and Fourier transform near-infrared (FT-NIR) spectroscopy combined with multivariate algorithms. Firstly, ultra-performance liquid chromatography-photodiode array (UPLC-PDA) combined with chemometric analyses was used to examine variations in the chemical profiles of CR. Secondly, the activation effect on blood circulation of CR was assessed using an in vitro antiplatelet aggregation assay. The studies revealed significant variations in chemical profiles and antiplatelet aggregation effects among CR samples from different botanical origins, with constituents such as germacrone, ß-elemene, bisdemethoxycurcumin, demethoxycurcumin, and curcumin showing a positive correlation with antiplatelet aggregation biopotency. Thirdly, FT-NIR spectroscopy was integrated with various machine learning algorithms, including Artificial Neural Network (ANN), K-Nearest Neighbors (KNN), Logistic Regression (LR), Support Vector Machine (SVM), and Subspace K-Nearest Neighbors (Subspace KNN), to classify CR samples from four distinct sources. The result showed that FT-NIR combined with KNN and SVM classification algorithms after SNV and MSC preprocessing successfully distinguished CR samples from four plant sources with an accuracy of 100%. Finally, Quantitative models for active constituents and antiplatelet aggregation bioactivity were developed by optimizing the partial least squares (PLS) model with interval combination optimization (ICO) and competitive adaptive reweighted sampling (CARS) techniques. The CARS-PLS model achieved the best predictive performance across all five components. The coefficient of determination (R2p) and root mean square error (RMSEP) in the independent test sets were 0.9708 and 0.2098, 0.8744 and 0.2065, 0.9511 and 0.0034, 0.9803 and 0.0066, 0.9567 and 0.0172 for germacrone, ß-elemene, bisdemethoxycurcumin, demethoxycurcumin and curcumin, respectively. The ICO-PLS model demonstrated superior predictive capabilities for antiplatelet aggregation biotency, achieving an R2p of 0.9010, and an RMSEP of 0.5370. This study provides a valuable reference for the quality evaluation of CR in a more rapid and comprehensive manner.
Asunto(s)
Curcuma , Inhibidores de Agregación Plaquetaria , Agregación Plaquetaria , Espectroscopía Infrarroja Corta , Curcuma/química , Espectroscopía Infrarroja Corta/métodos , Agregación Plaquetaria/efectos de los fármacos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Inhibidores de Agregación Plaquetaria/análisis , Inhibidores de Agregación Plaquetaria/química , Animales , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Algoritmos , Extractos Vegetales/químicaRESUMEN
OBJECTIVE: To investigate the effects of platelet-specific Rictor knockout on platelet activation and thrombus formation in mice. METHODS: PF4-Cre and Rictorfl/fl transgenic mice were crossed to obtain platelet-specific Rictor knockout (Rictor-KO) mice and wild-type mice (n=65), whose expression levels of Rictor, protein kinase B (AKT) and p-AKT were detected using Western blotting. Platelet counts of the mice were determined using routine blood tests, and hemostatic function was assessed by tail vein hemorrhage test. Venous thrombosis models were established in the mice to evaluate the effect of Rictor knockout on thrombosis. Platelet aggregation induced by ADP and thrombin was observed in Rictor-KO and wild-type mice, and flow cytometry was used to analyze the expression levels of integrin αIIbß3 and CD62P in resting and activated platelets. Plasma PF4 levels were determined with ELISA. Megakaryocytes from Rictor-KO and wild-type mice were incubated by vWF immunohistochemical antibody and APC-CD41 antibody to detect the number and ploidy of megakaryocytes, respectively. Platelet elongation on collagen surface was observed with scanning electron microscopy. RESULTS: Compared with the wild-type mice, Rictor-KO mice showed significantly decreased AKT phosphorylation, decreased platelet production, reduced thrombosis, and decreased platelet activation in response to ADP and thrombin stimulation. The Rictor-KO mice also showed lowered expression level of P-selectin protein and activation of integrin αIIbß3 with suppression of platelet extension, reduced plasma PF4 level and decreased number of megakaryocytes in the bone marrow. The ploidy of megakaryocytes and the mean area of proplatelets were both significantly decreased in Rictor-KO mice. CONCLUSION: Platelet-specific Rictor knockout inhibits platelet generation and activation to result in decreased thrombus formation in mice, suggesting the potential of mTORC2 activity inhibition as an efficient antithrombotic strategy.
Asunto(s)
Plaquetas , Megacariocitos , Ratones Noqueados , Activación Plaquetaria , Proteínas Proto-Oncogénicas c-akt , Proteína Asociada al mTOR Insensible a la Rapamicina , Trombosis , Animales , Ratones , Proteína Asociada al mTOR Insensible a la Rapamicina/metabolismo , Proteína Asociada al mTOR Insensible a la Rapamicina/genética , Plaquetas/metabolismo , Trombosis/metabolismo , Trombosis/prevención & control , Megacariocitos/metabolismo , Megacariocitos/citología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Agregación Plaquetaria , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/genética , Selectina-P/metabolismo , Recuento de PlaquetasRESUMEN
Factor XII (FXII) is the zymogen of the plasma protease FXIIa that activates the intrinsic coagulation pathway and the kallikrein kinin-system. The role of FXII in inflammation has been obscure. Here, we report a single-domain antibody (nanobody, Nb) fused to the Fc region of a human immunoglobulin (Nb-Fc) that recognizes FXII in a conformation-dependent manner and interferes with FXIIa formation. Nb-Fc treatment inhibited arterial thrombosis in male mice without affecting hemostasis. In a mouse model of extracorporeal membrane oxygenation (ECMO), FXII inhibition or knockout reduced thrombus deposition on oxygenator membranes and systemic microvascular thrombi. ECMO increased circulating levels of D-dimer, alkaline phosphatase, creatinine and TNF-α and triggered microvascular neutrophil adherence, platelet aggregation and their interaction, which were substantially attenuated by FXII blockade. Both Nb-Fc treatment and FXII knockout markedly ameliorated immune complex-induced local vasculitis and anti-neutrophil cytoplasmic antibody-induced systemic vasculitis, consistent with selectively suppressed neutrophil migration. In human blood microfluidic analysis, Nb-Fc treatment prevented collagen-induced fibrin deposition and neutrophil adhesion/activation. Thus, FXII is an important mediator of inflammatory responses in vasculitis and ECMO, and Nb-Fc provides a promising approach to alleviate thrombo-inflammatory disorders.
Asunto(s)
Factor XII , Inflamación , Ratones Noqueados , Neutrófilos , Anticuerpos de Dominio Único , Trombosis , Animales , Humanos , Trombosis/inmunología , Trombosis/metabolismo , Anticuerpos de Dominio Único/farmacología , Anticuerpos de Dominio Único/inmunología , Masculino , Factor XII/metabolismo , Factor XII/antagonistas & inhibidores , Inflamación/metabolismo , Ratones , Neutrófilos/inmunología , Neutrófilos/metabolismo , Neutrófilos/efectos de los fármacos , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Agregación Plaquetaria/efectos de los fármacos , Factor XIIa/metabolismo , Factor XIIa/antagonistas & inhibidores , Fibrina/metabolismo , Productos de Degradación de Fibrina-Fibrinógeno/metabolismoRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Every year, cardiovascular diseases (CVDs) account for about 17.9 million deaths, making them the primary cause of both morbidity and mortality. Conventional drugs, which are often prescribed to treat cardiovascular diseases, are costly and have adverse effects. Consequently, dietary modifications and other medications are needed. Traditional use of Solanum indicum as cardiotonic to treat hypertension and anticoagulant potency has been reported but poorly evaluated scientifically. AIM OF THE STUDY: This study investigated the in vivo anticoagulant activity and mechanism of anticoagulation of quercetin (QC), a bioactive compound isolated from S. indicum (SI) hydroethanolic fruit extract. MATERIALS AND METHODS: Bioassay-guided fractionation (anticoagulant activity) extracted QC from hydroethanolic SI extract. QC was extensively characterized biochemically and pharmacologically. The interaction between QC and thrombin was investigated using spectrofluorometric and isothermal calorimetric methods. Cytotoxicity, antiplatelet, and thrombolytic studies were carried out in vitro. The Swiss albino mice were used to assess the in vivo, anticoagulant, and antithrombotic activities of QC. RESULTS: QC exhibits anticoagulant activity via (i) uncompetitive inhibition of thrombin but not FXa with a Ki value of 33.11 ± 4.2 µM and (ii) a partial inhibition of thrombin-catalyzed platelet aggregation with an IC50 value of 13.2 ± 1.2 µM. The experimental validation of the in silico study's prediction of QC's binding to thrombin was confirmed by spectrofluorometric and isothermal calorimetric analyses. QC was nontoxic to mammalian, non-hemolytic cells and demonstrated thrombolytic activity by activating plasminogen. QC demonstrated in vivo anticoagulant efficacy, preventing k-carrageen-induced thrombus formation in mice's tails. In the acute circulatory stasis paradigm in mice, QC reduces thromboxane B2 (TXB2) and endothelin-1 (ET-1) while increasing nitric oxide synthase (eNOS) and 6-keto prostaglandin F1α (6-keto-PGF1 α). CONCLUSION: Effective in vivo anticoagulant and antithrombotic properties of S. indicum's bioactive component QC point to the plant's potential use as a herbal anticoagulant medication for preventing and treating cardiovascular diseases linked to thrombosis.
Asunto(s)
Anticoagulantes , Fibrinolíticos , Extractos Vegetales , Agregación Plaquetaria , Quercetina , Solanum , Animales , Quercetina/farmacología , Quercetina/aislamiento & purificación , Ratones , Fibrinolíticos/farmacología , Fibrinolíticos/aislamiento & purificación , Solanum/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Anticoagulantes/farmacología , Anticoagulantes/aislamiento & purificación , Humanos , Agregación Plaquetaria/efectos de los fármacos , Masculino , Plantas Medicinales/química , Trombosis/tratamiento farmacológico , Trombosis/prevención & control , Frutas/química , Trombina , Simulación del Acoplamiento Molecular , Inhibidores de Agregación Plaquetaria/farmacología , Inhibidores de Agregación Plaquetaria/aislamiento & purificación , Coagulación Sanguínea/efectos de los fármacosRESUMEN
Inherited bleeding disorders such as Glanzmann thrombasthenia (GT) lack prophylactic treatment options. As a result, serious bleeding episodes are treated acutely with blood product transfusions or frequent, repeated intravenous administration of recombinant activated coagulation factor VII (rFVIIa). Here we describe HMB-001, a bispecific antibody designed to bind and accumulate endogenous FVIIa and deliver it to sites of vascular injury by targeting it to the TREM (triggering receptor expressed on myeloid cells)-like transcript-1 (TLT-1) receptor that is selectively expressed on activated platelets. In healthy nonhuman primates, HMB-001 prolonged the half-life of endogenous FVIIa, resulting in its accumulation. Mouse bleeding studies confirmed antibody-mediated potentiation of FVIIa hemostatic activity by TLT-1 targeting. In ex vivo models of GT, HMB-001 localized FVIIa on activated platelets and potentiated fibrin-dependent platelet aggregation. Taken together, these results indicate that HMB-001 has the potential to offer subcutaneous prophylactic treatment to prevent bleeds in people with GT and other inherited bleeding disorders, with a low-frequency dosing regimen.
Asunto(s)
Anticuerpos Biespecíficos , Animales , Anticuerpos Biespecíficos/farmacología , Anticuerpos Biespecíficos/uso terapéutico , Anticuerpos Biespecíficos/inmunología , Humanos , Factor VIIa , Plaquetas/metabolismo , Plaquetas/efectos de los fármacos , Plaquetas/inmunología , Ratones , Modelos Animales de Enfermedad , Hemorragia/prevención & control , Hemorragia/tratamiento farmacológico , Agregación Plaquetaria/efectos de los fármacos , Trombastenia/tratamiento farmacológico , Trombastenia/inmunología , Ratones Endogámicos C57BL , Femenino , Masculino , Macaca fascicularis , Activación Plaquetaria/efectos de los fármacosRESUMEN
Platelet aggregation is a dynamic process that can obstruct blood flow, leading to cardiovascular diseases. While many studies have demonstrated clear connections between shear rate and platelet aggregation, the impact of flow-derived mechanical signals on this process is not fully understood. The objective of this work is to investigate the role of flow conditions on platelet aggregation dynamics, including effects on growth, shape, density composition, and their potential correlation with binding processes that are characterised by longer (e.g., via αIIbß3 integrin) and shorter (e.g., via VWF) initial binding times. In vitro blood perfusion experiments were conducted at wall shear rates of 800, 1600 and 4000 s-1. Detailed analysis of two modalities of experimental images was performed to offer insights into the morphology of platelet aggregates. A consistent structural pattern was observed across all samples: a high-density core enveloped by a low-density outer shell. An image-based 3D computational blood flow model was subsequently employed to study the local flow conditions, including binding availability time and flow-derived mechanical signals via shear rate and rate of elongation. The results show substantial dependence of the aggregation dynamics on these flow parameters. We found that the different binding mechanisms that prefer different flow regimes do not have a monotonic cross-over in efficiency as the flow increases. There is a significant dip in the cumulative aggregation potential in-between the preferred regimes. The results suggest that treatments targeting the biomechanical pathways could benefit from creating conditions that exploit these low-efficiency zones of aggregation.
Asunto(s)
Plaquetas , Agregación Plaquetaria , Humanos , Agregación Plaquetaria/fisiología , Plaquetas/fisiología , Plaquetas/citología , Plaquetas/metabolismo , Modelos Cardiovasculares , Velocidad del Flujo Sanguíneo/fisiología , Estrés MecánicoRESUMEN
OBJECTIVE: To explore the causes of platelet aggregation in version 6.4 Trima Accel automated blood collection system and the effect of 2 intervention measures. METHODS: The data on platelet aggregation (n=61) and non-aggregation (n=323) of 61 donors in 2020 were collected and the causes of aggregation were analyzed. Then the 72 donors with platelet aggregation in 2021 were randomized into intervention group A (increasing the anticoagulant-to-blood ratio) and intervention group B (wrapping the donor's arm with an electric blanket to keep warm and improve the blood flow speed). The collection time, average blood flow speed, number of machine alarms, anticoagulant usage, deaggregation and citrate reaction of the two groups were compared. RESULTS: Platelet aggregation was negatively correlated with the average blood flow speed (r =-0.394) and positively correlated with the collection time (r =0.458). The equations for predicting aggregation and non-aggregation were constructed based on Bayesian and Fisher discriminant analysis, and the predicted accuracy was 77.1%. The comparison of the effects of two intervention measures showed that the average blood flow speed in group B was higher than that in group A; the collection time, number of machine alarms, anticoagulant usage and proportion of citrate reaction in blood donors in group B were all lower than those in Group A, all these differences were significant (P < 0.05). In the entire cohort in 2021, 90.28% of the products were immediately deaggregated after collection, and 9.72% of the products were deaggregated within 4 hours. There was no statistically significant difference in deaggregation between the two intervention groups (P >0.05). CONCLUSION: During apheresis platelet collection, the predictive equations for aggregation and non-aggregation can be used to predict the occurrence probability of aggregation, and the intervention can be made in advance. Both intervention measures are effective in reducing platelet aggregation, however, measure B has the advantages of improving the speed of blood collection, shortening the collection time, reducing the alarm frequency and the anticoagulant usage, and reducing the incidence of citrate reaction in blood donors.
Asunto(s)
Anticoagulantes , Agregación Plaquetaria , Humanos , Donantes de Sangre , PlaquetoferesisRESUMEN
Increasing evidence is implicating roles for platelets in the development and progression of ovarian cancer, a highly lethal disease that can arise from the fallopian tubes, and has no current method of early detection or prevention. Thrombosis is a major cause of mortality of ovarian cancer patients suggesting that the cancer alters platelet behavior. The objective of this study was to develop a cell culture model of the pathological interactions of human platelets and ovarian cancer cells, using normal FT epithelial cells as a healthy control, and to test effects of the anti-platelet dihomo-gamma-linolenic acid (DGLA) in the model. Both healthy and cancer cells caused platelet aggregation, however platelets only affected spheroid formation by cancer cells and had no effect on healthy cell spheroid formation. When naturally-formed spheroids of epithelial cells were exposed to platelets in transwell inserts that did not allow direct interactions of the two cell types, platelets caused increased size of the spheroids formed by cancer cells, but not healthy cells. When cancer cell spheroids formed using magnetic nanoshuttle technology were put in direct physical contact with platelets, the platelets caused spheroid condensation. In ovarian cancer cells, DGLA promoted epithelial-to-mesenchymal (EMT) transition at doses as low as 100 µM, and inhibited metabolic viability and induced apoptosis at doses ≥150 µM. DGLA doses ≤150 µM used to avoid direct DGLA effects on cancer cells, had no effect on the pathological interactions of platelets and ovarian cancer cells in our models. These results demonstrate that the pathological interactions of platelets with ovarian cancer cells can be modeled in cell culture, and that DGLA has no effect on these interactions, suggesting that targeting platelets is a rational approach for reducing cancer aggressiveness and thrombosis risk in ovarian cancer patients, however DGLA is not an appropriate candidate for this strategy.
Asunto(s)
Ácido 8,11,14-Eicosatrienoico , Plaquetas , Células Epiteliales , Neoplasias Ováricas , Esferoides Celulares , Humanos , Plaquetas/efectos de los fármacos , Femenino , Células Epiteliales/efectos de los fármacos , Neoplasias Ováricas/patología , Ácido 8,11,14-Eicosatrienoico/farmacología , Ácido 8,11,14-Eicosatrienoico/análogos & derivados , Esferoides Celulares/efectos de los fármacos , Línea Celular Tumoral , Agregación Plaquetaria/efectos de los fármacos , Técnicas de Cultivo de Célula/métodos , Comunicación Celular/efectos de los fármacosRESUMEN
Impedance aggregometry is an alternative to light transmission aggregometry that allows analysis of platelet function in whole blood samples. We hypothesized (1) impedance aggregometry would produce repeatable results, (2) inhibition of cyclooxygenase with aspirin would attenuate aggregation responses to collagen and abolish the aggregation response to arachidonic acid (AA), and (3) thromboxane receptor antagonism (terutroban) would attenuate the aggregation response to AA. Venous blood was obtained from 11 participants three times separated by at least 2 weeks. One sample followed 7-day-aspirin intervention (81 mg once daily; ASA), the others no intervention (control). Aggregation was induced using 1 µg/mL collagen ([col 1]), 5 µg/mL collagen ([col 5]), and 50 mM AA via impedance aggregometry to determine total aggregation (AUC) analyzed for intra-test repeatability, inter-test repeatability, intervention (ASA or control), and incubation (saline or terutroban). [col 1] showed high intra-test (p ≤ 0.03 visit 1 and 2) and inter-test repeatability (p < 0.01). [col 5] and AA showed intra- ([col 5] p < 0.01 visit 1 and 2; AA p < 0.001 visit 1 and 2) but not inter-test repeatability ([col 5] p = 0.48; AA p = 0.06). ASA attenuated AUC responses to [col 1] (p < 0.01), [col 5] (p = 0.03), and AA (p < 0.01). Terutroban attenuated AUC in response to AA (p < 0.01). [col 1] shows sufficient repeatability for longitudinal investigations of platelet function. [col 5] and AA may be used to investigate mechanisms of platelet function and metabolism at a single time point.
Asunto(s)
Aspirina , Inhibidores de la Ciclooxigenasa , Impedancia Eléctrica , Agregación Plaquetaria , Pruebas de Función Plaquetaria , Propionatos , Receptores de Tromboxanos , Humanos , Agregación Plaquetaria/efectos de los fármacos , Masculino , Proyectos Piloto , Femenino , Inhibidores de la Ciclooxigenasa/farmacología , Aspirina/farmacología , Receptores de Tromboxanos/antagonistas & inhibidores , Receptores de Tromboxanos/metabolismo , Adulto , Pruebas de Función Plaquetaria/métodos , Propionatos/farmacología , Naftalenos/farmacología , Ácido Araquidónico/farmacología , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/farmacología , Colágeno/farmacologíaRESUMEN
Platelets are key mediators of atherothrombosis, yet, limited tools exist to identify individuals with a hyperreactive platelet phenotype. In this study, we investigate the association of platelet hyperreactivity and cardiovascular events, and introduce a tool, the Platelet Reactivity ExpreSsion Score (PRESS), which integrates platelet aggregation responses and RNA sequencing. Among patients with peripheral artery disease (PAD), those with a hyperreactive platelet response (>60% aggregation) to 0.4 µM epinephrine had a higher incidence of the 30 day primary cardiovascular endpoint (37.2% vs. 15.3% in those without hyperreactivity, adjusted HR 2.76, 95% CI 1.5-5.1, p = 0.002). PRESS performs well in identifying a hyperreactive phenotype in patients with PAD (AUC [cross-validation] 0.81, 95% CI 0.68 -0.94, n = 84) and in an independent cohort of healthy participants (AUC [validation] 0.77, 95% CI 0.75 -0.79, n = 35). Following multivariable adjustment, PAD individuals with a PRESS score above the median are at higher risk for a future cardiovascular event (adjusted HR 1.90, CI 1.07-3.36; p = 0.027, n = 129, NCT02106429). This study derives and validates the ability of PRESS to discriminate platelet hyperreactivity and identify those at increased cardiovascular risk. Future studies in a larger independent cohort are warranted for further validation. The development of a platelet reactivity expression score opens the possibility for a personalized approach to antithrombotic therapy for cardiovascular risk reduction.
Asunto(s)
Plaquetas , Enfermedades Cardiovasculares , Enfermedad Arterial Periférica , Agregación Plaquetaria , Humanos , Enfermedad Arterial Periférica/sangre , Enfermedad Arterial Periférica/epidemiología , Masculino , Femenino , Plaquetas/metabolismo , Persona de Mediana Edad , Anciano , Agregación Plaquetaria/efectos de los fármacos , Enfermedades Cardiovasculares/sangre , Factores de Riesgo de Enfermedad Cardiaca , Activación Plaquetaria , Epinefrina/sangre , Factores de RiesgoRESUMEN
Thrombosis is the primary cause of death in patients with cancer. Resveratrol inhibits platelet activation, a crucial pathophysiological basis of thrombosis, in healthy individuals. However, its effects and mechanisms of action in patients with colon cancer remain unknown. Here, we investigated the effect of resveratrol on platelet adhesion and aggregation in patients with colon cancer. Through numerous in vitro and in vivo analyses, including flow cytometry, western blotting, ELISA, and immunofluorescence and colon cancer rat models, we demonstrated that resveratrol reduced thrombosis in patients with colon cancer by inhibiting the phosphorylation of the MAPK and activating the cyclic-GMP/vasodilator-stimulated phosphoprotein pathway. These findings demonstrate the potential of resveratrol in reducing thrombosis in patients with colon cancer and could be used to develop novel therapeutic strategies for this condition.
Asunto(s)
Moléculas de Adhesión Celular , Neoplasias del Colon , GMP Cíclico , Fosfoproteínas , Activación Plaquetaria , Resveratrol , Trombosis , Resveratrol/farmacología , Resveratrol/uso terapéutico , Trombosis/tratamiento farmacológico , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/complicaciones , Humanos , Animales , Activación Plaquetaria/efectos de los fármacos , Masculino , Ratas , GMP Cíclico/metabolismo , Moléculas de Adhesión Celular/metabolismo , Fosfoproteínas/metabolismo , Femenino , Estilbenos/farmacología , Estilbenos/uso terapéutico , Ratas Sprague-Dawley , Persona de Mediana Edad , Transducción de Señal/efectos de los fármacos , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Agregación Plaquetaria/efectos de los fármacos , Proteínas de MicrofilamentosRESUMEN
BACKGROUND: Titanium dioxide nanoparticles (TiO2NPs) are widely used in medical application. However, the relevant health risk has not been completely assessed, the potential of inducing arterial thrombosis (AT) in particular. METHODS: Alterations in platelet function and susceptibility to arterial thrombosis induced by TiO2NPs were examined using peripheral blood samples from healthy adult males and an in vivo mouse model, respectively. RESULTS: Here, using human platelets (hPLTs) freshly isolated from health volunteers, we demonstrated TiO2NP treatment triggered the procoagulant activity of hPLTs through phosphatidylserine exposure and microvesicles generation. In addition, TiO2NP treatment increased the levels of glycoprotein IIb/IIIa and P-selectin leading to aggregation and activation of hPLTs, which were exacerbated by providing physiology-mimicking conditions, including introduction of thrombin, collagen, and high shear stress. Interestingly, intracellular calcium levels in hPLTs were increased upon TiO2NP treatment, which were crucial in TiO2NP-induced hPLT procoagulant activity, activation and aggregation. Moreover, using mice in vivo models, we further confirmed that TiO2NP treatment a reduction in mouse platelet (mPLT) counts, disrupted blood flow, and exacerbated carotid arterial thrombosis with enhanced deposition of mPLT. CONCLUSIONS: Together, our study provides evidence for an ignored health risk caused by TiO2NPs, specifically TiO2NP treatment augments procoagulant activity, activation and aggregation of PLTs via calcium-dependent mechanism and thus increases the risk of AT.
Asunto(s)
Plaquetas , Activación Plaquetaria , Agregación Plaquetaria , Trombosis , Titanio , Titanio/toxicidad , Animales , Humanos , Agregación Plaquetaria/efectos de los fármacos , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Masculino , Trombosis/inducido químicamente , Ratones , Activación Plaquetaria/efectos de los fármacos , Adulto , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Coagulación Sanguínea/efectos de los fármacos , Ratones Endogámicos C57BL , Selectina-P/metabolismo , Calcio/metabolismo , Calcio/sangre , Nanopartículas/toxicidad , Nanopartículas del Metal/toxicidadRESUMEN
During coronary artery bypass grafting (CABG), the surgical procedure, particularly the manipulation of the major arteries of the heart, induces a significant inflammatory state that may compromise platelet function to the extent that platelet transfusion is required. Given stored platelets as a major source of biological mediators, this study investigates the effects of platelet transfusion on the major pro-aggregatory, pro-inflammatory and immunomodulatory markers of platelets. Platelets from 20 patients, 10 who received platelet transfusion and 10 without, were subjected to flow cytometery where P-selectin and CD40 ligand (CD40L) expressions and PAC-1 binding (activation-specific anti GPIIb/GPIIIa antibody) analysed at five-time points of 24 h before surgery, immediately, 2 h, 24 h and 1 week after surgery. Analysis of intra-platelet transforming growth factor-beta-1 (TGF-ß1) was also conducted using western blotting. Patients with platelet transfusion showed increased levels of P-selectin, CD40L and intra-platelet TGF-ß1 2-h after surgery compared to those without transfusion (p < 0.05). PAC-1 binding was increased 24 h after surgery in transfused patients (p < 0.05). Given the significant post-transfusion elevation of platelet TGF-ß1, P-sel/CD40L reduction in transfused patients a week after was of much interest. This study showed for the first time the significant effects of platelet transfusion on the pro-inflammatory, pro-aggeregatory and immunomodulatory state of platelets in CABG patients, which manifested with immediate, midterm and delayed consequences. While the increased pro-inflammatory conditions manifested as an immediate effect of platelet transfusion, the pro-aggregatory circumstances emerged 24 h post-transfusion. A week after surgery, attenuations of pro-inflammatory markers of platelets in transfused patients were shown, which might be due to the immunomodulatory effects of TGF-ß1.
Asunto(s)
Plaquetas , Ligando de CD40 , Puente de Arteria Coronaria , Selectina-P , Transfusión de Plaquetas , Humanos , Puente de Arteria Coronaria/efectos adversos , Plaquetas/metabolismo , Masculino , Femenino , Selectina-P/sangre , Selectina-P/metabolismo , Persona de Mediana Edad , Ligando de CD40/sangre , Ligando de CD40/metabolismo , Anciano , Factor de Crecimiento Transformador beta1/sangre , Factor de Crecimiento Transformador beta1/metabolismo , Inflamación/sangre , Agregación PlaquetariaRESUMEN
BACKGROUND: Individuals with kidney failure have a compromised haemostatic system making them susceptible to both thrombosis and bleeding. OBJECTIVES: Assessment of primary haemostasis in patients treated with either haemodialysis (HD) or haemodiafiltration (HDF) was performed through the measurement of several coagulation-based tests, both pre- and post-dialysis. PATIENTS/METHODS: 41 renal failure patients and 40 controls were recruited. Platelet aggregometry, Factor XIII (FXIII), Fibrinogen, Von Willebrand Factor (VWF) and Soluble P-Selectin (sP-Sel) levels were measured. RESULTS: Maximum platelet aggregation was diminished in renal patients irrespective of aspirin intake. Post-dialysis, platelet function was exacerbated. Pre-dialysis FXIII levels were similar to the healthy cohort and became elevated post-dialysis. This elevation could not be explained by the relative decrease of water by dialysis. Fibrinogen levels were already elevated pre-dialysis and further increased post-dialysis. This elevation was associated with the relative decrease of water by dialysis. VWF levels in males were similar to the healthy cohort and became elevated post-dialysis. This elevation was associated with dialysis-related water loss. VWF antigen and activity in female patients were already elevated pre-dialysis and further increased post-dialysis with the exception of VWF activity in HDF treated female patients. sP-Sel levels were lower than those of the healthy cohort and became similar to the healthy cohort post-dialysis. This elevation could not be explained by the relative decrease of water by dialysis. CONCLUSIONS: Whilst platelet aggregometry was diminished, we noted elevated clotting factors such as fibrinogen, FXIII and VWF with no significant differences between HD and HDF-treated patients.
Asunto(s)
Hemodiafiltración , Hemostasis , Diálisis Renal , Humanos , Femenino , Masculino , Persona de Mediana Edad , Diálisis Renal/efectos adversos , Anciano , Agregación Plaquetaria , Factor de von Willebrand/metabolismo , Factor de von Willebrand/análisis , Adulto , Insuficiencia Renal/terapia , Insuficiencia Renal/sangre , Fibrinógeno/análisis , Fibrinógeno/metabolismoRESUMEN
BACKGROUND: This study aimed to explore the effect of a P2Y12 inhibitor regimen on the occurrence of postoperative atrial fibrillation (POAF) after off-pump coronary artery bypass graft surgery in carriers with the cytochrome P450 family 2 subfamily C member19 loss-of-function allele. METHODS AND RESULTS: From May 2019 to November 2023, patients containing the cytochrome P450 family 2 subfamily C member19*2 or *3 allele undergoing elective first-time off-pump coronary artery bypass graft surgery including aspirin 100 mg/d and ticagrelor 180 mg/d (AT group; n=95) versus clopidogrel 75 mg/d (aspirin and clopidogrel group; n=95) were prospectively followed. The primary end point was the cumulative incidence of POAF in a week. The secondary end points were POAF burden, platelet aggregability, systemic immune-inflammation index and heart rate variability. The incidence of POAF was 21.1% in the AT group versus 41.1% in the aspirin and clopidogrel group (hazard ratio, 0.46 [95% CI, 0.27-0.76]; P=0.003). POAF burden, ADP-induced platelet aggregation and systemic immune-inflammation index was notably lower in the AT group than the aspirin and clopidogrel group. Heart rate variability data showed an increase in both high-frequency and SD of normal-to-normal RR intervals in the AT group with a decreased low-frequency/high-frequency ratio, suggesting that the sympathetic/parasympathetic activation was balanced. CONCLUSIONS: In patients carrying the cytochrome P450 family 2 subfamily C member19 loss-of-function allele, an AT regimen after off-pump coronary artery bypass grafting was associated with a lower incidence of POAF, paralleled by lower atrial fibrillation burden, ADP-induced platelet aggregation, lower systemic immune-inflammation index reaction, and a balanced automatic nerve system compared with an aspirin and clopidogrel regimen. Inhibiting the systemic immune-inflammation response and sustaining automatic nerve balance may underlie the therapeutic effect of POAF by a potent antiplatelet combination.
Asunto(s)
Fibrilación Atrial , Clopidogrel , Puente de Arteria Coronaria Off-Pump , Inhibidores de Agregación Plaquetaria , Ticagrelor , Humanos , Clopidogrel/uso terapéutico , Clopidogrel/efectos adversos , Ticagrelor/uso terapéutico , Fibrilación Atrial/etiología , Fibrilación Atrial/epidemiología , Fibrilación Atrial/prevención & control , Fibrilación Atrial/diagnóstico , Masculino , Femenino , Puente de Arteria Coronaria Off-Pump/efectos adversos , Persona de Mediana Edad , Anciano , Inhibidores de Agregación Plaquetaria/uso terapéutico , Inhibidores de Agregación Plaquetaria/efectos adversos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Incidencia , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2C19/metabolismo , Estudios Prospectivos , Agregación Plaquetaria/efectos de los fármacos , Antagonistas del Receptor Purinérgico P2Y/uso terapéutico , Antagonistas del Receptor Purinérgico P2Y/efectos adversos , Enfermedad de la Arteria Coronaria/cirugía , Resultado del TratamientoRESUMEN
BACKGROUND: Although artificial and non-nutritive sweeteners are widely used and generally recognized as safe by the US and European Union regulatory agencies, there have been no clinical trials to assess either long-term cardiovascular disease risks or short-term cardiovascular disease-relevant phenotypes. Recent studies report that fasting plasma levels of erythritol, a commonly used sweetener, are clinically associated with heightened incident cardiovascular disease risks and enhance thrombosis potential in vitro and in animal models. Effects of dietary erythritol on thrombosis phenotypes in humans have not been examined. METHODS: Using a prospective interventional study design, we tested the impact of erythritol or glucose consumption on multiple indices of stimulus-dependent platelet responsiveness in healthy volunteers (n=10 per group). Erythritol plasma levels were quantified with liquid chromatography tandem mass spectrometry. Platelet function at baseline and following erythritol or glucose ingestion was assessed via both aggregometry and analysis of granule markers released. RESULTS: Dietary erythritol (30 g), but not glucose (30 g), lead to a >1000-fold increase in erythritol plasma concentration (6480 [5930-7300] versus 3.75 [3.35-3.87] µmol/L; P<0.0001) and exhibited acute enhancement of stimulus-dependent aggregation responses in all subjects, agonists, and doses examined. Erythritol ingestion also enhanced stimulus-dependent release of the platelet dense granule marker serotonin (P<0.0001 for TRAP6 [thrombin activator peptide 6] and P=0.004 for ADP) and the platelet α-granule marker CXCL4 (C-X-C motif ligand-4; P<0.0001 for TRAP6 and P=0.06 for ADP). In contrast, glucose ingestion triggered no significant increases in stimulus-dependent release of either serotonin or CXCL4. CONCLUSIONS: Ingestion of a typical quantity of the non-nutritive sweetener erythritol, but not glucose, enhances platelet reactivity in healthy volunteers, raising concerns that erythritol consumption may enhance thrombosis potential. Combined with recent large-scale clinical observational studies and mechanistic cell-based and animal model studies, the present findings suggest that discussion of whether erythritol should be reevaluated as a food additive with the Generally Recognized as Safe designation is warranted. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04731363.
Asunto(s)
Plaquetas , Eritritol , Glucosa , Voluntarios Sanos , Agregación Plaquetaria , Trombosis , Humanos , Eritritol/sangre , Eritritol/administración & dosificación , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Masculino , Trombosis/sangre , Trombosis/inducido químicamente , Trombosis/prevención & control , Estudios Prospectivos , Agregación Plaquetaria/efectos de los fármacos , Femenino , Adulto , Edulcorantes no Nutritivos/administración & dosificación , Edulcorantes no Nutritivos/efectos adversos , Adulto Joven , Factor Plaquetario 4/sangre , Espectrometría de Masas en Tándem , Persona de Mediana Edad , Serotonina/sangre , Edulcorantes/administración & dosificación , Pruebas de Función PlaquetariaRESUMEN
ACKR3, an atypical chemokine receptor, has been associated with prothrombotic events and the development of cardiovascular events. We designed, synthesized, and evaluated a series of novel small molecule ACKR3 agonists. Extensive structure-activity relationship studies resulted in several promising agonists with potencies ranging from the low micromolar to nanomolar range, for example, 23 (EC50 = 111 nM, Emax = 95%) and 27 (EC50 = 69 nM, Emax = 82%) in the ß-arrestin-recruitment assay. These compounds are selective for ACKR3 versus ACKR2, CXCR3, and CXCR4. Several agonists were subjected to investigations of their P-selectin expression reduction in the flow cytometry experiments. In particular, compounds 23 and 27 showed the highest potency for platelet aggregation inhibition, up to 80% and 97%, respectively. The most promising compounds, especially 27, exhibited good solubility, metabolic stability, and no cytotoxicity, suggesting a potential tool compound for the treatment of platelet-mediated thrombosis.
Asunto(s)
Diseño de Fármacos , Inhibidores de Agregación Plaquetaria , Agregación Plaquetaria , Receptores CXCR , Humanos , Inhibidores de Agregación Plaquetaria/farmacología , Inhibidores de Agregación Plaquetaria/síntesis química , Inhibidores de Agregación Plaquetaria/química , Relación Estructura-Actividad , Agregación Plaquetaria/efectos de los fármacos , Receptores CXCR/agonistas , Receptores CXCR/metabolismo , Animales , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/síntesis química , Selectina-P/metabolismo , Plaquetas/efectos de los fármacos , Plaquetas/metabolismoRESUMEN
BACKGROUND AND PURPOSE: More evidence supports the benefits of batroxobin combined with anticoagulation in correcting acute cerebral venous thrombosis (CVT). The dynamic fluctuations of peripheral blood platelets, fibrinolysis, and coagulation biomarkers during this therapy were analyzed. METHODS: We investigated batroxobin's effects on the antithrombotic system under two regimens. The pretreatment group included patients on anticoagulants for at least 1 week before starting batroxobin. The simultaneous treatment group began both treatments upon admission. The control group received only anticoagulation. Batroxobin was given on alternate days at doses of 10BU, 5BU, and 5BU, totaling three doses. Anticoagulation was continuous. Baseline data were T0; the next day after each batroxobin dose was T1, T2, and T3. Data from these four time points was analyzed. RESULTS: The time-point paired sample T-test results of the pretreatment group [n = 60; mean age (SD), 43.3(16.5); 38 (63.35%) women] showed that batroxobin significantly inhibited ADP-induced platelet aggregation rate (T1-T0: p = 0.015; T2-T0: p = 0.025; T3-T0: p = 0.013), decreased fibrinogen level (T1-T0: p < 0.001; T2-T0: p < 0.001; T3-T0: p < 0.001), and increased D-dimer (T1-T0:p < 0.001; T2-T0: p < 0.001; T3-T0: p < 0.001), TT (T1-T0:p = 0.046; T2-T0: p = 0.003; T3-T0: p < 0.001), and APTT (T1-T0:p = 0.021; T2-T0: p = 0.012; T3-T0: p = 0.026). Compared to the control group, the simultaneous treatment group showed significantly higher TT (T2: p = 0.002; T3: p = 0.004) and D-dimer (T1: p < 0.001; T2: p < 0.001; T3: p < 0.001) values, while fibrinogen (T2: p < 0.001; T3: p < 0.001) levels were significantly lower. Using batroxobin can alleviate the amplitude of changes in coagulation indicators other than TT caused by anticoagulants. The above conclusions are consistent with the results of repeated measurement data analysis. CONCLUSIONS: Batroxobin can significantly inhibit ADP-induced platelet aggregation rate, increase D-dimer, decrease fibrinogen, and prolong TT and APTT in the presence of anticoagulant agents. Using batroxobin can reduce the amplitude of changes in coagulation indicators caused by anticoagulants. These results reveal the potential mechanism of batroxobin combined with anticoagulation in the safe and effective treatment of CVT.
Asunto(s)
Batroxobina , Trombosis Intracraneal , Trombosis de la Vena , Humanos , Batroxobina/farmacología , Masculino , Femenino , Persona de Mediana Edad , Adulto , Trombosis Intracraneal/tratamiento farmacológico , Trombosis Intracraneal/sangre , Trombosis de la Vena/tratamiento farmacológico , Fibrinolíticos/farmacología , Fibrinolíticos/uso terapéutico , Agregación Plaquetaria/efectos de los fármacos , Anticoagulantes/farmacología , Anticoagulantes/uso terapéutico , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Anciano , Plaquetas/efectos de los fármacos , Plaquetas/metabolismoRESUMEN
ABSTRACT: Monoclonal antibodies (mAbs) have provided valuable information regarding the structure and function of platelet αIIbß3. Protein disulfide isomerase (PDI) has been implicated in αIIbß3 activation and binds to thrombin-activated αIIbß3. Using human platelets as the immunogen, we identified a new mAb (R21D10) that inhibits the binding of PDI to platelets activated with thrombin receptor-activating peptide (T6). R21D10 also partially inhibited T6-induced fibrinogen and PAC-1 binding to platelets, as well as T6- and adenosine 5'-diphosphate-induced platelet aggregation. Mutual competition experiments showed that R21D10 does not inhibit the binding of mAbs 10E5 (anti-αIIb cap domain) or 7E3 (anti-ß3 ß-I domain), and immunoblot studies indicated that R21D10 binds to ß3. The dissociation of αIIbß3 by EDTA had a minimal effect on R21D10 binding. Cryogenic electron microscopy of the αIIbß3-R21D10 Fab complex revealed that R21D10 binds to the ß3 integrin-epidermal growth factor 1 (I-EGF1) domain and traps an intermediate conformation of αIIbß3 with semiextended leg domains. The binding of R21D10 produces a major structural change in the ß3 I-EGF2 domain associated with a new interaction between the ß3 I-EGF2 and αIIb thigh domains, which may prevent the swing-out motion of the ß3 hybrid domain required for high-affinity ligand binding and protect αIIbß3 from EDTA-induced dissociation. R21D10 partially reversed the ligand binding priming effect of eptifibatide, suggesting that it could convert the swung-out conformation into a semiextended conformation. We concluded that R21D10 inhibits ligand binding to αIIbß3 via a unique allosteric mechanism, which may or may not be related to its inhibition of PDI binding.