Platelet Aggregation Research Articles

Influence of heart rate variability on platelet hemostasis by average aggregate size in patients with chronic coronary heart disease in combination with COVID-19

BACKGROUND. In order to prevent complications of coronavirus infection (platelet hemostasis disorders, heart rate variability and QT interval dispersion, which increase the risk of thromboembolic complications and fatal arrhythmias), it is promising to study the relationship between heart rate variability and platelet hemostasis in patients with coronary artery disease (CAD) in combination with coronavirus disease (COVID-19). OBJECTIVE. The aim of the study was to investigate the impact of COVID-19 on the interdependence of changes in platelet hemostasis and heart rate variability in patients with CAD. MATERIALS AND METHODS. We examined 102 patients divided into three groups: group 1 – CAD without COVID-19 (n=32); group 2 – CAD in combination with COVID-19 (n=35); group 3 – COVID-19 without CAD (n=35). The control group included 30 conditionally healthy individuals. Changes in platelet hemostasis were studied according to laser aggregometry by the Born method and analysis of the average size of aggregates with an assessment of spontaneous aggregation and aggregation induced by adenosine diphosphate (ADP), arachidonic acid, epinephrine, collagen, ristomycin. Heart rate variability parameters and QT interval variability characteristics were determined by the results of 24-hour Holter electrocardiogram monitoring. RESULTS AND DISCUSSION. The time for spontaneous aggregation was longer in all patients compared to the control group, with the highest values observed in groups 2 and 3 (with COVID-19). In ADP aggregation, the control group showed higher results. The rate of aggregation in ADP was lowest in group 2. Collagen-induced aggregation was higher in COVID-19 cases. All groups exhibited lower values of adrenaline-induced aggregation, with the lowest values in group 3. The time of aggregation under adrenaline was shortest in group 2. Ristocetin induced greater aggregation in the control group, but the lowest rate in group 2, and the shortest time in group 1 (СAD without COVID-19). In СAD with COVID-19, an inverse relationship was observed between the parasympathetic nervous system and adrenaline-induced aggregation, as well as between sympathetic activity and ristocetin-induced aggregation. The degree of platelet aggregation induced by ADP had a direct correlation with the corrected QT interval. The rate of aggregation with ADP had an inverse correlation with the mean QT. The time of platelet aggregation activated by ristocetin had an inverse correlation with the standard deviation of QT(NN). The mode of QT had an inverse correlation with the degree of aggregation with ristocetin. CONCLUSIONS. In СAD and COVID-19, platelet hemostatic function is impaired, as confirmed by laser aggregometry data. Autonomous dysregulation and prolonged QT interval have been identified. A complex interaction between platelet hemostasis and heart rate variability is observed. Considering platelet hemostatic function, heart rate variability, and QT dispersion is crucial for treating this cohort of patients.

Deficiency of neutrophil gelatinase-associated lipocalin elicits Hemophilia-like bleeding and clotting disorder.

Coagulation is related to inflammation, but the key pathway, especially innate immune system and coagulation regulation, is not well understood and need to be further explored. Here, we demonstrated that neutrophil gelatinase-associated lipocalin (NGAL), an innate immune inflammatory mediator, is upregulated in thrombosis patients. Furthermore, it contributes to the initiation and amplification of coagulation, hemostasis, and thrombosis. This occurs by enhancing tissue factor expression on the cell surface, potentiating various clotting factors such as thrombin, kallikrein, FXIa, and FVIIa, promoting thrombin-induced platelet aggregation, and inhibiting antithrombin. NGAL knockout led to strikingly prolonged clot reaction time and kinetic time in thromboelastography analysis, along with reduced thrombus generation angle and lower thrombus maximum amplitude, which were in line with remarkably prolonged activated partial thromboplastin time and prothrombin time. In several mouse hemostasis and thrombosis models, NGAL overexpression or intravenous administration promoted coagulation and hemostasis and aggravated thrombosis whereas NGAL knockout or treatment with anti-NGAL monoclonal antibody significantly prolonged bleeding time and alleviated thrombus formation. Notably, NGAL knockout prolonged mouse tail bleeding time or artery occlusion time to over 40 or 60 min, respectively, resembling uncontrollable bleeding and clotting disorder seen in Hemophilia mice. Furthermore, anti-NGAL monoclonal antibody treatment markedly reduced the formation of blood clots in inflammation-induced thrombosis models. Collectively, these findings unveil a previously unidentified role of NGAL in the processes of coagulation, hemostasis, and thrombosis, as well as the crosstalk between innate immunity, inflammation, and coagulation. Thus, modulating NGAL levels could potentially help balance thrombotic and hemorrhagic risks.

α-Synuclein Deletion Impairs Platelet Function: A Role for SNARE Complex Assembly

Granule secretion is an essential platelet function that contributes not only to haemostasis but also to wound healing, inflammation, and atherosclerosis. Granule secretion from platelets is facilitated, at least in part, by Soluble N-ethylmaleimide-Sensitive Factor (NSF) Attachment Protein Receptor (SNARE) complex-mediated granule fusion. Although α-synuclein is a protein known to modulate the assembly of the SNARE complex in other cells, its role in platelet function remains poorly understood. In this study, we provide evidence that α-synuclein is critical for haemostasis using α-synuclein-deficient (−/−) mice. The genetic deletion of α-synuclein resulted in impaired platelet aggregation, secretion, and adhesion in vitro. In vivo haemostasis models showed that α-synuclein−/− mice had prolonged bleeding times and activated partial thromboplastin times (aPTTs). Mechanistically, platelet activation induced α-synuclein serine (ser) 129 phosphorylation and re-localisation to the platelet membrane, accompanied by an increased association with VAMP 8, syntaxin 4, and syntaxin 11. This phosphorylation was calcium (Ca2+)- and RhoA/ROCK-dependent and was inhibited by prostacyclin (PGI2). Our data suggest that α-synuclein regulates platelet secretion by facilitating SNARE complex formation.

A randomized, double-blind, placebo controlled study to evaluate the effect of alpha-lipoic acid on inhibition of ADP-and collagen-induced platelet aggregation ex vivo in diabetic neuropathy patients on gabapentin or pregabalin.

Diabetic peripheral neuropathy (DPN) is a chronic microvascular complication in diabetic mellitus patients due to chronic hyperglycemia, resulting in platelet hyperactivity and dyslipidemia. Alpha-lipoic acid (ALA) is a potent antioxidant which has antiplatelet activity and lipid-modulating characteristics and plays a major role in the prevention of disease progression. To evaluate the effect of ALA on inhibition of platelet aggregation and lipid profile. This was a prospective, randomized, double-blind, placebo-controlled study conducted at the Department of Clinical Pharmacology and Therapeutics at a tertiary care hospital. We recorded efficacy parameters including changes in inhibition of platelet aggregation, lipid profile, blood sugars, and glycated hemoglobin over 12 weeks of ALA (600 mg once daily orally) supplementation in DPN patients on gabapentin (300 mg twice daily [BD]) or pregabalin (75 mg BD) compared to placebo. We used Student's t-test paired and unpaired for within-group and between-group comparisons, respectively. A total of 52 study participants (males = 22, females = 30) with a mean age 55.63 ± 7.5 years were randomized to receive either ALA or placebo. Between-group analysis at 12 weeks showed that ALA significantly inhibited both collagen-induced platelet aggregation (from 32.61 ± 8.00 to 24.88 ± 5.30; P < 0.001) and adenosine diphosphate-induced platelet aggregation (from 34.00 ± 6.97 to 25.96 ± 6.45; P < 0.001) compared to placebo. Significant reduction in total cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and triglycerides was found in the ALA group at 12 weeks compared to baseline. No serious adverse events were reported. ALA, an antioxidant, demonstrated a protective effect against DPN by the virtue of its inhibitory effect on platelet aggregation and lipid-modulating effects and was found to have good safety.

Exploring the morphine-platelet activity association in patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention

ST-segment elevation myocardial infarction (STEMI) is usually caused by a ruptured atherosclerotic plaque, with subsequent thrombus formation. Platelet inhibition and primary percutaneous coronary intervention (PCI) are essential treatments. Morphine, used to relieve pain and anxiety in STEMI patients, delays the onset of P2Y12 inhibitors. This study aimed to further explore the association between platelet activity and morphine treatment in patients with STEMI. In this sub-study of the VALIDATE-SWEDHEART trial, 89 STEMI patients treated with ticagrelor, and primary PCI were included. Platelet aggregation and biomarkers of platelet activity, coagulation, and inflammation (sP-selectin, thrombin-antithrombin complexes, prothrombin fragments 1 + 2, CD40L, CRP, beta-thromboglobulin, and pentraxin3) were assessed at three time points: before, one, and twelve hours after PCI. Of the 89 patients, 40 received morphine before hospital arrival. There were no significant differences in age, sex, medical history, or coronary disease extent. One hour after PCI, ADP-induced (36 vs 61, p < .001), arachidonic acid-induced (20 vs 36, p = .003), collagen-induced (48 vs 60, p = .03) aggregation, and the proportion of high on-treatment ADP-induced platelet reactivity (27% vs 60%, p = .001) were significantly higher in morphine-treated patients. No significant differences were found before or 12 hours after PCI. No significant differences in platelet activity biomarkers were observed. Morphine increased platelet aggregation in STEMI patients but did not affect biomarkers.

Isorhynchophylline inhibits platelet activation and thrombus formation.

Isorhynchophylline is a Chinese herbal medicine and has multiple effects such as anti-inflammatory and neuroprotective effects. Whether isorhynchophylline has anti-thrombotic property is unknown. This study aims to evaluate its role in platelet function. Human platelets were incubated with isorhynchophylline (0, 10, 20 and 40 μM) at 37°C for 1 hour to detect platelet aggregation and activation, receptors level, spreading and calcium mobilization. Additionally, isorhynchophylline (5 mg/kg) was injected into mice to measure in vivo hemostasis and thrombosis. Isorhynchophylline dose-dependently reduced platelet aggregation, ATP secretion, P-selectin expression and αIIbβ3 activation induced by collagen-related peptide (CRP) or thrombin without affecting surface level of receptors αIIbβ3, GPIbα, and GPVI. Meanwhile, isorhynchophylline-treated platelets showed reduced spreading. Moreover, isorhynchophylline reduced platelet calcium mobilization, phosphatidylserine exposure and the phosphorylation of PLCγ2 and PKCα. Furthermore, administration of isorhynchophylline into mice impaired platelet hemostatic function and arterial/venous thrombosis without affecting coagulation. In conclusion, Isorhynchophylline impairs platelet function and arterial/venous thrombosis, implying its potential to be a novel agent for treating thrombotic or cardiovascular diseases.

Fluid Dynamic and in Vitro Blood Study to Understand Catheter-Related Thrombosis.

Central venous catheters (CVCs) provide a direct route to the venous circulation but are prone to catheter-related thrombosis (CRT). A known CRT risk factor is a high catheter-to-vein ratio (CVR), or a large catheter diameter with respect to the indwelling vein size. In this study, the CVR's effect on CVC hemodynamics and its impact on CRT is investigated with in vitro and in silico experiments. An in vitro flow loop is used to characterize the hemodynamics around CVCs using particle image velocimetry. In addition, CRT is investigated using an in vitro flow loop with human blood and clinical catheters. The wall shear rate of flow around the CVC is computed numerically. CVRs of 0.20, 0.33, and 0.49 and Reynolds numbers of 200, 800, and 1300 are evaluated. No flow is used through CVC lumens to model chronic indwelling catheters. Results show CVR ≥ 0.33 promotes platelet-rich clot growth at the device tip and at an increased rate compared to lower CVR cases. A high wall shear rate gradient on the CVC tip and an extended wake distal to the tip exists for higher CVR cases, promoting the aggregation of platelets and subsequent stagnation for clot formation. Further, the combination of the CVR and Reynolds number are crucial to CRT potential, not the CVR alone. Specifically, thrombosis risk is increased with low (stasis driven) and/or high (platelet activation driven) flow conditions, with the CVR and CVC's geometry playing an additional role in promoting fluid mechanic driven thrombus development. A high CVR (≥ 0.33) and high flow condition (≥ 1300) results in the highest risk for clot growth at the tip of the device; other locations of the device are at risk for thrombus development in lower flow conditions, regardless of the CVR. The importance of the device geometry and flow in promoting thrombus and fibrin sheath formation is also shown for the device investigated. This work demonstrates that the CVR, flow, and device geometry affect CRT. For clinical cases with CVR ≥ 0.33 and/or Re ≥ 1300, the device tip may be monitored more consistently for clot formation. Thrombosis risks remain on the entire catheter, regardless of the flow condition, for a CVR = 0.49. Device placement should be chosen carefully with respect to the combination of the Reynolds number and CVR. Further study is needed on the effect of catheterization to confirm these findings.

Platelet inhibition by hypochlorous acid involves cAMP signalling.

Hypochlorous acid (HOCl), made by neutrophil-derived myeloperoxidase, has been suggested to inhibit platelets, however, the mechanisms involved have not been described. Here we confirm that HOCl exposure changes platelet morphology and inhibits platelet spreading and aggregation. HOCl effects could be reversed by glutathione suggesting a role for cysteine oxidation. Mass spectrometry-based proteomics of HOCl-exposed platelets revealed oxidised cysteine residues in 37 proteins including adenylate cyclase 6 and Rap1B. Adenylate cyclase is involved in the inhibitory cAMP pathway triggered by endothelium-derived prostacyclin and Rap1 is a small G protein required for integrin αIIbβ3 activation and platelet aggregation. We show that HOCl exposure stimulates cAMP production and phosphorylation of the cAMP-dependent protein kinase substrate VASP in platelets and transfected HEK293T cells. In addition, HOCl inhibited Rap1-GTP formation. These data suggest that HOCl inhibits platelets at least in part through the cAMP pathway and by regulating Rap1. Thus, this study provides new insights into HOCl mediated crosstalk between neutrophils and platelets.

A study of platelet function in patients with chronic immune thrombocytopenia treated with thrombopoietin receptor agonists

BackgroundThrombopoietin receptor agonists (TPO-RAs) are widely used in immune thrombocytopenia (ITP) and are associated with increased thrombotic risk. However, data regarding their impact on platelet function is scarce. MethodsPlatelet function was evaluated in chronic ITP patients enrolled over one year, using light transmission aggregometry and platelet-derived microparticle (PMP) levels measurement with flow cytometry. Aggregation responses to various concentrations of ADP, collagen, ristocetin, and PMP levels were compared between TPO-RA-treated patients, patients treated with other agents and healthy individuals. ResultsTPO-RA-treated patients (n = 24) displayed significantly reduced aggregation responses to 2.5 μM, 5 μM, and 10 μM of ADP and collagen compared to 15 healthy individuals (59.5 % vs. 87.6 %, p < .0001, 43.6 % vs. 79.9 %, p < .0001, 26.1 % vs. 75.2 %, p < .0001, 67.2 % vs. 86 %, p < .0001, respectively). Reduced responses to ADP and collagen were also recorded in patients treated with other agents (n = 16) compared to healthy controls but without difference between the two treatment groups. Aggregation response to ristocetin was normal in all three groups. None of the patients yielded enhanced platelet aggregation. In TPO-RA-treated patients, a strong positive correlation between platelet counts and aggregation response to ristocetin was observed (rs = 0.65, p = .0005). PMP levels were significantly elevated in TPO-RA-treated patients compared to patients treated with other agents (49.5 vs 4.5 events/uL, p < .0001) and healthy controls (5 events/uL, p < .0001). ConclusionsThese results suggest that TPO-RAs may not enhance platelet aggregation responses, whereas impaired responses may be a disease feature. Furthermore, TPO-RAs may increase PMP levels and thus be implicated in the modulation of platelet function in ITP patients.

Essential Structural Profile of Novel Adenosine Derivatives as Antiplatelet Aggregation Inhibitors based on 3D-QSAR Analysis

Aims: In this research, 3D-QSAR evaluation on a set of fresh purinoid compounds that we produced was conducted. This analysis aims to illustrate the correlation between the structure of purine and its ability to prevent platelet aggregation. Our findings could pave the way to discovering novel antithrombotic medications. Background: The incidence of cardiovascular disease triggered by the clumping of platelets poses a significant danger to human health. Purine derivatives are important molecules with antiplatelet aggregation activity. Objective: The objectives of this research are to establish the correlation between the structure of purine and its ability to prevent platelet aggregation. Such a correlation could aid in the development of innovative antithrombotic medications. Methods: In this study, 3D-QSAR investigation on a collection of 75 new purine derivatives, which we synthesized, was conducted, utilizing Comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). Results: Significant correlation coefficients (CoMFA, q2= 0.843, r2= 0.930, F value= 266.755, SEE= 0.165; CoMSIA, q2= 0.869, r2= 0.918, F value= 222.571, SEE= 0.179) were obtained, and assessed the model's predictive capabilities by validating it with the test set. Conclusion: Our findings indicate that the introduction of an appropriately sized structure at position 2 of the compound yields significant benefits. Conversely, the attachment of an excessively large group is detrimental. Direct attachment of a bulky substituent at C-6 of the compound is not feasible, and its activity increases when the structure with low electron cloud density is added. Moreover, the presence of a voluminous functional group at the 5' position of the compound is advantageous, and its activity will be further increased by the presence of hydrogen bond receptors in this region. These discoveries furnish significant comprehension for the formation of innovative structures with heightened efficacy.

Platelet aggregation responses to Salmonella Typhimurium are determined by host anti-Salmonella antibody levels.

Invasive non-typhoidal Salmonella infections are responsible for >75 000 deaths/year and >500 000 cases/year globally. Seventy-five percent of these cases occur in Sub-Saharan Africa, an increasing number of which are from multi-drug resistant strains. Interactions between bacteria and platelets can lead to thrombus formation, which can be beneficial for control of infection (immunothrombosis), or harmful through uncontrolled inflammation and organ damage (thromboinflammation). It is unknown whether Salmonella Typhimurium can activate human platelets. To assess this, light transmission aggregometry was used to measure platelet activation by two different Salmonella Typhimurium strains in 26healthy donors in platelet-rich plasma and washed platelets. In platelet-rich plasma, but not in washed platelets, Salmonella Typhimurium activated platelets in a donor- and strain-dependent manner mediated through the low affinity immune receptor FcγRIIA and the feedback agonists, ADP and thromboxane A2. Plasma swap studies between strong and weak responders demonstrated a plasma component was responsible for the variation between donors. Depletion of anti-Salmonella antibodies from plasma abolished Salmonella-induced platelet aggregation responses, and addition of polyclonal anti-Salmonella antibody allowed aggregation in washed platelets. Correlating levels of anti-Salmonella total IgG or the IgG1, IgG2, IgG3 and IgG4 subclasses to platelet responses revealed total IgG levels, rather than levels of individual subclasses, positively correlated with maximum platelet aggregation results, and negatively with lag times. Overall, we show that anti-Salmonella IgG antibodies are responsible for donor variation in platelet aggregation responses to Salmonella and mediate this activity through FcγRIIA.

The role of protein kinase C and the glycoprotein Ibα cytoplasmic tail in anti-glycoprotein Ibα antibody-induced platelet apoptosis and thrombocytopenia

IntroductionImmune thrombocytopenia (ITP) is an autoimmune disease characterized by low platelet counts. ITP patients with anti-platelet glycoprotein (GP) Ibα (a subunit of GPIb-IX-V complex) autoantibodies, which induce Fc-independent signaling and platelet clearance, are refractory to conventional treatment. Protein kinase C (PKC) is activated by the binding of the ligand von Willebrand factor to GPIbα and regulates VWF-GPIbα-induced platelet activation. However, the role of PKC in anti-GPIbα antibody-induced thrombocytopenia remains unknown. Materials and methodsThe anti-GPIbα antibody-induced PKC activation and its underlying mechanisms were first detected by Western blot, and then the effects of PKC inhibitors, PKC knockout, or GPIbα C-terminal removal on anti-GPIbα antibody-induced platelet apoptosis, activation, aggregation, and clearance were investigated by flow cytometry, platelet aggregometry, and platelet posttransfusion, respectively. Meanwhile, platelet retention and co-localization with macrophages in the liver were detected by spinning disc intravital confocal microscopy. ResultsAnti-GPIbα antibody-induced PKC activation depends on GPIbα clustering and phosphoinositide 3-kinase (PI3K) activation and results in Akt phosphorylation. Pharmacologic inhibition or genetic ablation of PKC suppresses anti-GPIbα antibody-induced platelet apoptosis and activation. Moreover, the GPIbα cytoplasmic tail is required for antibody-induced PKC activation, platelet apoptosis, and activation. Inhibition or ablation of PKC and deletion of the GPIbα cytoplasmic tail protect platelets from clearance in vivo. ConclusionsOur study indicates the important role of PKC and the GPIbα cytoplasmic tail in anti-GPIbα antibody-mediated platelet signaling and clearance and suggests a novel therapeutic target for ITP and other thrombocytopenic diseases.

Improved survival of advanced melanoma patients receiving immunotherapy with concomitant antithrombotic therapy – A multicenter study on 2419 patients from the prospective skin cancer registry ADOReg

BackgroundCancer immunotherapy has revolutionized melanoma treatment, but the high number of non-responders still emphasizes the need for improvement of therapy. One potential avenue for enhancing anti-tumor treatment is through the modulation of coagulation and platelet activity. Both have been found to play an important role in the tumor microenvironment, tumor growth and metastasis. Preclinical studies indicate a beneficial effect, clinical data has been inconsistent. MethodsWe examined a cohort of advanced, non-resectable melanoma patients (n = 2419) derived from the German prospective multicenter skin cancer registry ADOReg, who were treated with immune checkpoint inhibitors (ICI). The patients were classified based on whether it was documented that they received platelet aggregation inhibition (PAI) (n = 137) (acetylsalicylic acid (ASA) or clopidogrel), anticoagulation (AC) (n = 185) (direct oral anticoagulation (DOAC), phenprocoumon, heparins) at the start of ICI or no antithrombotic medication (n = 2097) at any point during ICI treatment. The study endpoints were best overall response (BOR), progression-free survival (PFS) and overall survival (OS). ResultsA significantly improved PFS was observed in patients documented to receive ASA (15.1 vs 6.4 months, HR 0.67, 95 % CI: 0.5 to 0.88, p = 0.0047) as well as in patients to receive AC (15.1 vs. 6.4 months, HR 0.7, 95 % CI: 0.53 to 0.91, p = 0.01) compared to patients for whom no antithrombotic medication was documented. Multivariate analysis of OS showed significant risk reduction in patients who received DOAC (HR 0.68, 95 % CI: 0.49 to 0.92, p = 0.0170) or phenprocoumon (HR: 0.44, 95 % CI: 0.19 to 0.85, p = 0.0301). ConclusionOur study indicates a positive prognostic effect of anticoagulant and antiplatelet concomitant medication in melanoma patients receiving ICI. Further studies are needed to confrim the cancer-related benefit of adding anticoagulation or platelet inhibition to ICI treatment.

Green Tea Epigallocatechin 3-Gallate Reduced Platelet Aggregation and Improved Anticoagulant Proteins in Patients with Transfusion-Dependent β-Thalassemia: A Randomized Placebo-Controlled Clinical Trial.

Patients with transfusion-dependent β-thalassemia (TDT) with iron overload have been linked to hypercoagulability and increased platelet (PLT) activation that causes thrombosis. Green tea extract (GTE) rich in epigallocatechin-3-gallate (EGCG) exerts iron-chelating and antithrombotic properties. The study aimed to assess the effects of GTE treatment on plasma coagulation state and PLT function in vitro and in patients with TDT. The subjects consumed a placebo or GTE tablets (50 mg and 2 × 50 mg EGCG equivalent) every day for two months. Blood was then collected from the treated patients for analyses of PLT numbers, agonist-induced PLT aggregation, and anti-coagulation proteins. In our findings indicate that the in vitro treatment of GTE (at least 1 mg EGCG equivalent) inhibited PLT aggregation in patients who were healthy and with thalassemia platelet-rich plasma (PRP), which was significant in the healthy PRP. Consistently, GTE treatment inhibited the PLT aggregation that had been ex vivo generated by collagen or ADP. In addition, consumption of GTE tablets greatly inhibited PLT aggregation and increased the plasma levels of proteins C and S, as well as the free protein S concentrations depending upon the time course, but not the GTE dosage. Moreover, plasma ferritin levels decreased in both green tea tablet groups in a time-dependent manner (p < 0.05 in the second month). In conclusion, EGCG-rich GTE diminished PLT aggregation in patients who were healthy and patients with thalassemia plasma. It also improved PLT aggregation and hypercoagulability in patients with TDT by increasing the antithrombotic activity of protein C and protein S. This would suggest an adjuvant of GTE could reduce the risk of thrombosis associated with iron overload.

The yeast carboxymethyl glucan reduces cardiometabolic risks by improving oxidative stress, endothelial dysfunction and platelet aggregation

The carboxymethyl glucan (CMG) obtained from Saccharomyces cerevisiae has been highlighted for its beneficial potential, especially for its high antioxidant capacity. Cardiovascular diseases are among the leading causes of death worldwide and are often associated with overweight and dietary intake. On the other hand, supplementation with bioactive foods may be important in the prevention and treatment of these diseases. In this sense, this study evaluated the effect of CMG on anthropometric, oxidative and cardiovascular variables. Wistar rats were divided into three groups: NCT - normal caloric control fed a standard diet; HCT - hypercaloric control; H-CMG - hypercaloric + CMG (20 mg/kg/day) fed a hypercaloric diet for 12 weeks. At the end of the experimental period, anthropometric variables, reactive oxygen species (ROS) production, vasorelaxation, platelet aggregation, and systolic blood pressure (SBP) were measured. The results demonstrated that hypercaloric diet induced weight gain, increased oxidative stress, and reduced endothelium-dependent vasorelaxation, as well as increased platelet aggregation levels and SBP. In addition, CMG induced a significant reduction on weight gain (68.3 ± 4.9 vs 111.1 ± 3.8) and tissue (65.3 ± 18.4 vs 176.7 ± 49.7) and platelet ROS production (464.0 ± 99.8 vs 679.0 ± 102.3), leading to improved vasorelaxation, and reduced platelet aggregation. However, CMG treatment did not significantly reduce SBP levels. In this sense, it is reasonable to conclude that CMG was effective in reducing the damage caused by a hypercaloric diet, emerging as a potential compound for the treatment of diseases characterized by these conditions, such as cardiometabolic disorders.

The use of non-steroidal anti-inflammatory drugs (NSAIDs) in clinical practice for the treatment of periodontitis: a narrative review

Abstract After dental caries, the most common multifactorial oral disease is periodontal disease. Periodontitis can result in biofilm and host dysbiosis, ultimately causing inflammation and destruction of periodontal tissues. This narrative review aimed to summarise and discuss the mechanism of action, categories and use of non-steroidal anti-inflammatory drugs (NSAIDs) in clinical practice in the treatment of periodontitis because of their analgesic, anti-inflammatory and reducing effects on platelet aggregation and thus bleeding. Also, this review illustrates the importance of studies demonstrating synergism between specialty drugs and their derivatives as valuable active substances. The eleven clinical trials conducted in small groups of adult volunteers (14-50) treated with various NSAIDs, e.g. aspirin, ibuprofen, diclofenac, ketoprofen and tenoxicam are discussed. The results of clinical trials have shown that the use of NSAIDs together with surgical intervention in the treatment of periodontal diseases produces beneficial effects as an adjunctive treatment. It is worth noting that these studies were conducted on small cohorts of adult volunteers, with variations in the duration of treatment and doses of administered drugs. Further research on the impact of NSAIDs administration on periodontal disease may provide in-depth knowledge of patient groups with different demographics, including age, gender and comorbidities. Additional research is necessary to explore the use of NSAIDs in combination with periodontitis treatment for different patient groups.

The identification of key genes and pathways in polycystic ovary syndrome by bioinformatics analysis of next-generation sequencing data

BackgroundPolycystic ovary syndrome (PCOS) is a reproductive endocrine disorder. The specific molecular mechanism of PCOS remains unclear. The aim of this study was to apply a bioinformatics approach to reveal related pathways or genes involved in the development of PCOS.MethodsThe next-generation sequencing (NGS) dataset GSE199225 was downloaded from the gene expression omnibus (GEO) database and NGS dataset analyzed is obtained from in vitro culture of PCOS patients’ muscle cells and muscle cells of healthy lean control women. Differentially expressed gene (DEG) analysis was performed using DESeq2. The g:Profiler was utilized to analyze the gene ontology (GO) and REACTOME pathways of the differentially expressed genes. A protein–protein interaction (PPI) network was constructed and module analysis was performed using HiPPIE and cytoscape. The miRNA-hub gene regulatory network and TF-hub gene regulatory network were constructed. The hub genes were validated by using receiver operating characteristic (ROC) curve analysis.ResultsWe have identified 957 DEG in total, including 478 upregulated genes and 479 downregulated gene. GO terms and REACTOME pathways illustrated that DEG were significantly enriched in regulation of molecular function, developmental process, interferon signaling and platelet activation, signaling, and aggregation. The top 5 upregulated hub genes including HSPA5, PLK1, RIN3, DBN1, and CCDC85B and top 5 downregulated hub genes including DISC1, AR, MTUS2, LYN, and TCF4 might be associated with PCOS. The hub gens of HSPA5 and KMT2A, together with corresponding predicted miRNAs (e.g., hsa-mir-34b-5p and hsa-mir-378a-5p), and HSPA5 and TCF4 together with corresponding predicted TF (e.g., RCOR3 and TEAD4) were found to be significantly correlated with PCOS.ConclusionsThese study uses of bioinformatics analysis of NGS data to obtain hub genes and key signaling pathways related to PCOS and its associated complications. Also provides novel ideas for finding biomarkers and treatment methods for PCOS and its associated complications.

The Role of Fibrinogen and platelets in mouse Liver Ischemia-Reperfusion Injury: Distribution and Pathophysiological Insights

Liver ischemia-reperfusion (I/R) injury is a critical issue in clinical settings, particularly in liver transplantation and resection, leading to severe hepatocellular dysfunction and organ failure. This study investigates the role of fibrinogen and platelets in liver I/R injury, focusing on their distribution and pathophysiological impact within liver lobules. Using a mouse model, we examined the expression and localization of fibrinogen and platelets at various time points post-reperfusion. In normal liver, fibrinogen is predominantly expressed in hepatic sinusoids near the portal vein, with sparse platelet distribution. Following I/R injury, fibrinogen expression significantly increases in hepatic sinusoids and hepatocytes, accompanied by substantial platelet aggregation and embolization, particularly in Zone 1 of the liver lobules. These findings highlight the zonal heterogeneity of fibrinogen distribution and its regulatory function in platelet adhesion and microthrombi formation. This study provides crucial insights for developing therapeutic strategies targeting fibrinogen and platelet interactions to mitigate liver I/R injury.

Systematic Selection of Limonoids from Carapa Guianesis Aublet with Anti-Inflammatory Activity, Through in Silico Techniques for Topical Use

Objective: The aim of this study is to investigate in silico the inhibitory activity of limonoids on the COX-1 enzyme and their liposolubility descriptors for topical actions against inflammation. Theoretical Framework: Andiroba oil has limonoids with anti-inflammatory potential, highlighting their potential for sustainable bioeconomy due to their classification as non-steroidal. In this context, nine limonoid structures were studied in silico via molecular docking to the COX-1 enzyme. Method: The 2D chemical structures of the limonoids were prepared using the MarvinSketch program, converted into 3D structures and optimized using classical mechanics methods. The structure of the COX-1 protein complexed with flurbiprofen in its active site was downloaded from the RCSB PDB of Homo sapiens origin and used for molecular docking using the Virtual Molegro Docker program. Results and Discussion: The results obtained demonstrated that limonoids have the potential to inhibit COX-1. These results showed valuable information on liposolubility and COX-1 inhibitory activity, highlighting the potential for topical use of andirobas oil. Research Implications: The practical and theoretical implications of this research emphasize that limonoids can inhibit COX-1 by preventing the formation of TXA2 thromboxanes, in addition to being associated with inhibition of platelet aggregation, being an effective measure in the prevention of arterial thrombosis, and which can be extended to vascular diseases, opening up perspectives for possible reduction, not only of microvaricose veins, but also of superficial phlebitis. Originality/Value: This study contributes to the literature as it is an unprecedented study involving COX-1 and the limonoids present in andirobeira oil.

Design and Synthesis of Butylphthalide-Hydroxycinnamic Acid Hybrid Derivatives as Potential Antiplatelet Agents.

Thirty-eight novel butylphthalide-hydroxycinnamic acid hybrid derivatives were designed and synthesized to discover effective antiplatelet agglutination drugs. Among these compounds, 3 o gave the optimal inhibitory activity against AA-induced platelet aggregation in vitro and also exhibited better inhibition than the precursor 3-n-butylphthalide (NBP) against thrombin-induced platelet contraction, carrageenan-induced tail thrombosis, and FeCl3-induced common carotid artery thrombosis. Further investigations on the anti-ischemic stroke activity revealed that compound 3 o exhibited a remarkable protective effect against ischemic/reperfusion brain injury. The PAMPA-BBB permeability and liver microsomal stability tests indicated that compound 3 o could traverse the blood-brain barrier and possessed favorable metabolic stability. This research provides a new candidate compound for treating and preventing cerebrovascular diseases caused by thrombosis.