Reduced Platelet Aggregation Research Articles

PHARMACOLOGICAL STRATEGIES TO PREVENT CARDIOVASCULAR EVENTS IN HIGH-RISK PATIENTS

INTRODUCTION: Cardiovascular diseases (CVDs) remain the leading cause of global mortality, and high-risk patients, such as those with a history of myocardial infarction, diabetes, uncontrolled hypertension, or severe dyslipidemia, are especially vulnerable to adverse cardiovascular events. Pharmacological strategies aimed at preventing these events in high-risk patients are essential to reduce morbidity and mortality associated with CVDs. These strategies include the use of antiplatelet agents, statins, angiotensin-converting enzyme inhibitors (ACEIs), and beta-blockers, which have shown efficacy in the secondary prevention of events such as myocardial infarction and stroke. OBJECTIVES: Given the importance of this topic, this study aims to explore the most effective pharmacological strategies to prevent cardiovascular events in patients considered at high risk. The study aims to elucidate the main drugs used, their mechanisms of action, as well as the relevance of their clinical application for the reduction of fatal and non-fatal cardiovascular events in these patients. METHODOLOGY: The study was developed based on an integrative literature review, based on searches in the Virtual Health Library (VHL), PubMed and SciELO databases. The search terms used included: “Cardiovascular prevention”, “High-risk patients”, and “Pharmacological strategies”. Articles published in the last five years were selected to ensure the relevance and timeliness of the information. RESULTS: Pharmacological strategies to prevent cardiovascular events in high-risk patients include the use of antiplatelet agents such as aspirin, which reduces platelet aggregation and prevents arterial thrombosis. Statins, which reduce LDL cholesterol levels, have been shown to significantly reduce the risk of myocardial infarction and stroke. In addition, ACE inhibitors and beta-blockers have shown benefits in patients with heart failure and hypertension, reducing cardiovascular mortality. Individualizing treatment, considering the comorbidities and characteristics of each patient, is essential to optimize clinical results. CONCLUSION: Pharmacological strategies play a crucial role in the prevention of cardiovascular events in high-risk patients. The combination of medications such as antiplatelet agents, statins, ACE inhibitors and beta-blockers, when applied individually and according to clinical guidelines, can significantly reduce the incidence of serious cardiovascular events. Awareness of the importance of the correct use of these therapies and adherence to treatment are essential to improve the quality of life and increase the longevity of patients.

A gain of function variant in RGS18 candidate for a familial mild bleeding syndrome

BackgroundInherited platelet diseases are bleeding disorders characterized by either defects in platelet count or platelet function, the latter being less common and very heterogeneous. Numerous gene variants associated with abnormal receptors, granules, and signaling pathways have been reported. Despite significant advancements in our understanding, many patients still lack a precise diagnosis. ObjectivesTo identify the genetic basis of a novel mild bleeding syndrome in a family exhibiting a selective defect of platelet aggregation. MethodsOur study included 6 family members across 3 generations who displayed reduced platelet aggregation in response to adenosine diphosphate, PAR1-AP, arachidonic acid, and epinephrine but not collagen. Platelet morphology, granule content, and expression of major surface glycoproteins were all found to be normal. Whole exome sequencing was performed for affected and nonaffected family members. ResultsWe identified RGS18, which encodes the regulator of G protein signaling (RGS) 18, as a candidate gene for the platelet function defect observed in this family. The RGS18 protein serves as a crucial negative regulator of G protein-coupled receptor signaling and coordinates the signaling pathways of natural platelet inhibitors. The heterozygous RGS18 c.643C>T, p.Arg215∗ variant was found to cosegregate among all 6 affected subjects. ConclusionTruncation at Arg215 removes the S216 and S218 phosphorylation sites, which are crucial regulatory domains for RGS18 activation. The impaired platelet function is thought to arise from excessive platelet downregulation due to constitutive activation of RGS18, resulting from a loss of association of the truncated form with the 14-3-3 protein.

Unexplored Opportunities of Utilizing Food Waste in Food Product Development for Cardiovascular Health.

Global food production leads to substantial amounts of agricultural and food waste that contribute to climate change and hinder international efforts to end food insecurity and poverty. Food waste is a rich source of vitamins, minerals, fibers, phenolic compounds, lipids, and bioactive peptides. These compounds can be used to create food products that help reduce heart disease risk and promote sustainability. This review examines the potential cardiovascular benefits of nutrients found in different food waste categories (such as fruits and vegetables, cereal, dairy, meat and poultry, and seafood), focusing on animal and clinical evidence, and giving examples of functional food products in each category. Current evidence suggests that consuming fruit and vegetable pomace, cereal bran, and whey protein may lower the risk of cardiovascular disease, particularly in individuals who are at risk. This is due to improved lipid profile, reduced blood pressure and increased flow-mediated dilation, enhanced glucose and insulin regulation, decreased inflammation, as well as reduced platelet aggregation and improved endothelial function. However, the intervention studies are limited, including a low number of participants and of short duration. Food waste has great potential to be utilized as cardioprotective products. Longer-term intervention studies are necessary to substantiate the health claims of food by-products. Technological advances are needed to improve the stability and bioavailability of bioactive compounds. Implementing safety assessments and regulatory frameworks for functional food derived from food waste is crucial. This is essential for maximizing the potential of food waste, reducing carbon footprint, and improving human health.

An exploration into CTEPH medications: Combining natural language processing, embedding learning, in vitro models, and real-world evidence for drug repurposing.

In the modern era, the growth of scientific literature presents a daunting challenge for researchers to keep informed of advancements across multiple disciplines. We apply natural language processing (NLP) and embedding learning concepts to design PubDigest, a tool that combs PubMed literature, aiming to pinpoint potential drugs that could be repurposed. Using NLP, especially term associations through word embeddings, we explored unrecognized relationships between drugs and diseases. To illustrate the utility of PubDigest, we focused on chronic thromboembolic pulmonary hypertension (CTEPH), a rare disease with an overall limited number of scientific publications. Our literature analysis identified key clinical features linked to CTEPH by applying term frequency-inverse document frequency (TF-IDF) scoring, a technique measuring a term's significance in a text corpus. This allowed us to map related diseases. One standout was venous thrombosis (VT), which showed strong semantic links with CTEPH. Looking deeper, we discovered potential repurposing candidates for CTEPH through large-scale neural network-based contextualization of literature and predictive modeling on both the CTEPH and the VT literature corpora to find novel, yet unrecognized associations between the two diseases. Alongside the anti-thrombotic agent caplacizumab, benzofuran derivatives were an intriguing find. In particular, the benzofuran derivative amiodarone displayed potential anti-thrombotic properties in the literature. Our in vitro tests confirmed amiodarone's ability to reduce platelet aggregation significantly by 68% (p = 0.02). However, real-world clinical data indicated that CTEPH patients receiving amiodarone treatment faced a significant 15.9% higher mortality risk (p<0.001). While NLP offers an innovative approach to interpreting scientific literature, especially for drug repurposing, it is crucial to combine it with complementary methods like in vitro testing and real-world evidence. Our exploration with benzofuran derivatives and CTEPH underscores this point. Thus, blending NLP with hands-on experiments and real-world clinical data can pave the way for faster and safer drug repurposing approaches, especially for rare diseases like CTEPH.

Alterations in visible light exposure modulate platelet function and regulate thrombus formation

BackgroundVariations in light exposure are associated with changes in inflammation and coagulation. The impact of light spectra on venous (VT) and arterial thrombosis is largely unexplored. ObjectivesTo investigate the impact of altering light spectrum on platelet function in thrombosis. MethodsWild type (WT) C57BL/6J mice were exposed to ambient (micewhite, 400lux), blue (miceblue, 442nm, 1,400lux), or red light (micered, 617nm, 1,400lux) with 12:12 hour light:dark cycle for 72 hours. After 72 hours of light exposure, platelet aggregation, activation, transcriptomic, and metabolomic changes were measured. The ability of released products of platelet activation to induce thrombosis-generating NET formation was quantified. Subsequent thrombosis was measured using murine models of VT and stroke. To translate our findings to human patients, light filtering cataract patients were evaluated over an 8-year period for rate of VTE with multivariable logistic regression clustered by hospital. ResultsExposure to long wavelength red light resulted in reduced platelet aggregation and activation. RNA-seq analysis demonstrated no significant transcriptomic changes between micered and micewhite. However, there were global metabolomic changes in platelets from micered compared to micewhite. Releasate from activated platelets resulted in reduced NET formation. Micered also had reduced VT weight and brain infarct size following stroke. On subgroup analysis of cataract patients, patients with a history of cancer have lower lifetime risk of VTE after implantation with lenses that filter low wavelength light. ConclusionsLight therapy may be a promising approach to thrombus prophylaxis by specifically targeting the intersection between innate immune function and coagulation.

The Causes of Platelet Aggregation in Version 6.4 Trima Accel Automated Blood Collection System and the Comparison of Two Intervention Measures

To explore the causes of platelet aggregation in version 6.4 Trima Accel automated blood collection system and the effect of 2 intervention measures. 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. 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). 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.

Argatroban- and copper-modified polymers with improved thromboresistance and antimicrobial properties

This paper describes a novel approach the development of biocompatible polyvinyl chloride (PVC) and polyurethane (PU) polymers, modified with copper (II) ions followed by the immobilisation the thrombin inhibitor argatroban (AG) using dopamine chemistry. The surface loading of the immobilised AG was 6.06 µg cm−2 on PVC and 6.66 µg cm−2 on PU, confirmed by FTIR and inhibitor concentration measurements. Both AG/Cu-modified polymers produced NO by catalytically decomposing S-nitrosothiol, reaching NO levels in plasma of 0.59 × 10–10molcm-2min-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ ext{mol} \\, {\ ext{cm}}^{-2} \\, {\ ext{min}}^{-1}$$\\end{document} for AG/Cu-PVC and 0.51 × 10–10molcm-2min-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ ext{mol} \\, {\ ext{cm}}^{-2} \\, {\ ext{min}}^{-1}$$\\end{document} for AG/Cu-PU, matching endothelial cell-produced physiological levels. This modification improved the haemocompatibility of the polymers through thrombin inhibition and reduced platelet aggregation and adhesion. Additionally, both modified polymers inhibited Staphylococcus aureus adhesion, growth and viability, confirming their acquired antibacterial properties. Antibacterial activity against Escherichia coli was also observed. These results demonstrate that modifying PVC and PU surfaces with copper (II) and AG produced materials with dual antithrombotic and antibacterial functions.Graphical abstract

Hydrogen Sulfide Promotes Platelet Autophagy via PDGFR-α/PI3K/Akt Signaling in Cirrhotic Thrombocytopenia.

The role of platelet autophagy in cirrhotic thrombocytopenia (CTP) remains unclear. This study aimed to investigate the impact of platelet autophagy in CTP and elucidate the regulatory mechanism of hydrogen sulfide (H2S) on platelet autophagy. Platelets from 56 cirrhotic patients and 56 healthy individuals were isolated for in vitro analyses. Autophagy markers (ATG7, BECN1, LC3, and SQSTM1) were quantified using enzyme-linked immunosorbent assay, while autophagosomes were visualized through electron microscopy. Western blotting was used to assess the autophagy-related proteins and the PDGFR/PI3K/Akt/mTOR pathway following treatment with NaHS (an H2S donor), hydroxocobalamin (an H2S scavenger), or AG 1295 (a selective PDGFR-α inhibitor). A carbon tetrachloride-induced cirrhotic BALB/c mouse model was established. Cirrhotic mice with thrombocytopenia were randomly treated with normal saline, NaHS, or hydroxocobalamin for 15 days. Changes in platelet count and aggregation rate were observed every three days. Cirrhotic patients with thrombocytopenia exhibited significantly decreased platelet autophagy markers and endogenous H2S levels, alongside increased platelet aggregation, compared to healthy controls. In vitro, NaHS treatment of platelets from severe CTP patients elevated LC3-II levels, reduced SQSTM1 levels, and decreased platelet aggregation in a dose-dependent manner. H2S treatment inhibited PDGFR, PI3K, Akt, and mTOR phosphorylation. In vivo, NaHS significantly increased LC3-II and decreased SQSTM1 expressions in platelets of cirrhotic mice, reducing platelet aggregation without affecting the platelet count. Diminished platelet autophagy potentially contributes to thrombocytopenia in cirrhotic patients. H2S modulates platelet autophagy and functions possibly via the PDGFR-α/PI3K/Akt/mTOR signaling pathway.

Non-clinical investigations about cytotoxic and anti-platelet activities of gamma-terpinene.

Gamma-terpinene (γ-TPN) is a cyclohexane monoterpene isolated from plant essential oils, such as tea tree (Melaleuca alternifolia), oregano (Origanum vulgare), rosemary (Rosmarinus officinalis L.), thyme (Thymus vulgaris Marchand), and eucalyptus (Eucalyptus sp.). Terpenes are widely studied molecules pharmacologically active on the cardiovascular system, hemostasis, and antioxidant actions. Herein, it was investigated the cytotoxic and antiplatelet activity of γ-TPN using different non-clinical laboratory models. For in silico evaluation, the PreADMET, SwissADME, and SwissTargetPrediction softwares were used. Molecular docking was performed using the AutoDockVina and BIOVIA Discovery Studio databases. The cytotoxicity of γ-TPN was analyzed by the MTT assay upon normal murine endothelial SVEC4-10 and fibroblast L-929 cells. Platelet aggregation was evaluated with platelet-rich (PRP) and platelet-poor (PPP) plasma from spontaneously hypertensive rats (SHR), in addition to SVEC4-10 cells pre-incubated with γ-TPN (50, 100, and 200 µM) for 24 h. SHR animals were pre-treated by gavage with γ-TPN for 7 days and divided into four groups (negative control, 25, 50, and 100 mg/kg). Blood samples were collected to measure nitrite using the Griess reagent. Gamma-TPN proved to be quite lipid-soluble (Log P = +4.50), with a qualified profile of similarity to the drug, good bioavailability, and adequate pharmacokinetics. It exhibited affinity mainly for the P2Y12 receptor (6.450 ± 0.232 Kcal/mol), moderate cytotoxicity for L-929 (CC50 = 333.3 µM) and SVEC 4-10 (CC50 = 366.7 µM)cells. The presence of γ-TPN in SVEC 4-10 cells was also able to reduce platelet aggregation by 51.57 and 44.20% at lower concentrations (50 and 100 µM, respectively). Then, γ-TPN has good affinity with purinergic receptors and an effect on the reversal of platelet aggregation and oxidative stress, being promising and safe for therapeutic targets and subsequent studies on the control of thromboembolic diseases.

Role of processing and encapsulation in the protection and bioaccessibility of phenolic compounds from Chilean Tórtola common bean (Phaseolus vulgaris L.)

The aim of this study was to extract, protect and increase the bioaccessibility of phenolic compounds extracted from the Chilean Tórtola common bean. For obtaining phenolic compounds, two methods were analyzed, focusing on their extraction and their drying. In the method where ultrasound-assisted extraction and spray drying were used, we obtained a yield five times greater than the conventional method. Thereafter, we evaluated an encapsulation system with two material shells, alginate and Eudragit L-100. The protective capacity of the capsules was verified by determining antioxidant capacity, total phenolic compounds content, as well as biomedical capacities of powder-encapsulated extract. Antithrombotic activity was evaluated as biomedical capacity, observing a 30% reduction in platelet aggregation. Additionally, quality characteristics were assessed using FITR, microscopic confocal, TGA, and hygrometry techniques. TGA analyses demonstrated the thermal protection of the capsule, reducing the degradation of encapsulated phenolic compounds by threefold compared to the non-encapsulated extract. Finally, two in vitro digestion models were used to simulate the physiological digestion. In both models, we observed an increase in TPC bioaccessibility even over 100%. These results would benefit biomedical applications and industrial processing of phenolic compounds extracted from common beans.

Abstract 3081: Competitive Inhibition Of Tlt-1/fibrinogen Molecular Interaction Disrupts Platelet Function In Ex Vivo Platelet Assays

Background: Platelets facilitate thrombosis, hemostasis, and immunity through their interaction with fibrinogen. Fibrinogen is the ligand for the platelet receptors αIIbβ3 and T REM- L ike T ranscript-1 (TLT-1), TLT-1 is an Ig-domain containing receptor released from platelet α-granules upon platelet activation. Unlike αIIbβ3, little is known about the TLT-1/fibrinogen interaction. Aims: Delineate the TLT-1/fibrinogen molecular interaction and determine if, peptides representing this interaction can regulate platelet function and inflammatory hemostasis. Methods: Octet Qke Bio-layer Interferometry and atomic force microscopy (AFM) were used to evaluate soluble TLT-1 binding to fibrinogen. Immunoprecipitation and a peptide array were used to determine which fibrinogen peptides bound TLT-1. Flow cytometry using FITC-labelled fibrinogen binding to activated human platelets and human platelet aggregometry in the presence of these peptides were used in competitive inhibition assays. Additionally, competitive ELISAs using peptides representing regions the TLT-1 extracellular domain incubated with soluble TLT-1 in a fibrinogen coated wells were used to identify the region(s) on TLT-1 interaction with fibrinogen. Results: We obtained an equilibrium dissociation constant (KD) of 3.02 ± 0.20 nM for the TLT-1/Fibrinogen interaction. AFM suggests that sTLT-1 mediates fibrinogen polymerization. Competitive inhibition assays suggest complementary determining loop-1 and LP-17 (a 17 amino acid region of TLT-1) mediate TLT-1’s interaction to fibrinogen. The 3D modeling of our identified peptides show that they form a binding complex on the B module of the D-domain rather than a single binding site. These peptides competitively reduce platelet aggregation in aggregation assays and decrease fibrinogen binding to platelets in flow cytometry assays compared to controls. Cell binding and clotting assays are underway and the current status of projected will be reported here. Conclusions: TLT-1 uses LP17 and CDR-1 to interact with the newly identified TLT-1 binding complex on fibrinogen. This TLT-1 binding surface may represent a targetable intervention to regulate thrombosis and inflammation.

Salvianolic acid B inhibits thrombosis and directly blocks the thrombin catalytic site

BackgroundSalvianolic acid B (SAB) is a major component of Salvia miltiorrhiza root (Danshen), widely used in East/Southeast Asia for centuries to treat cardiovascular diseases. Danshen depside salt, 85% of which is made up of SAB, is approved in China to treat chronic angina. Although clinical observations suggest that Danshen extracts inhibited arterial and venous thrombosis, the exact mechanism has not been adequately elucidated. ObjectiveTo delineate the antithrombotic mechanisms of SAB. MethodsWe applied platelet aggregation and coagulation assays, perfusion chambers, and intravital microscopy models. The inhibition kinetics and binding affinity of SAB to thrombin are measured by thrombin enzymatic assays, intrinsic fluorescence spectrophotometry, and isothermal titration calorimetry. We used molecular in silico docking models to predict the interactions of SAB with thrombin. ResultsSAB dose-dependently inhibited platelet activation and aggregation induced by thrombin. SAB also reduced platelet aggregation induced by adenosine diphosphate and collagen. SAB attenuated blood coagulation by modifying fibrin network structures and significantly decreased thrombus formation in mouse cremaster arterioles and perfusion chambers. The direct SAB-thrombin interaction was confirmed by enzymatic assays, intrinsic fluorescence spectrophotometry, and isothermal titration calorimetry. Interestingly, SAB shares key structural similarities with the trisubstituted benzimidazole class of thrombin inhibitors, such as dabigatran. Molecular docking models predicted the binding of SAB to the thrombin active site. ConclusionOur data established SAB as the first herb-derived direct thrombin catalytic site inhibitor, suppressing thrombosis through both thrombin-dependent and thrombin-independent pathways. Purified SAB may be a cost-effective agent for treating arterial and deep vein thrombosis.

Abstract 122: Deletion Of Pyruvate Dehydrogenase Kinases Reduces Susceptibility To Experimental Venous Thrombosis By Limiting Glycolysis In Neutrophils

Background: Neutrophils by releasing extracellular traps (NETs) provide a scaffold for platelet activation and coagulation, thereby facilitating venous thrombosis (VT) development. Emerging evidence suggests that neutrophil activation and NETs formation (NETosis) is an energy-intensive process, accompanied by an increased rate of aerobic glycolysis (lactate formation in the presence of oxygen). The metabolic enzymes pyruvate dehydrogenase kinases (PDKs) inhibit the pyruvate dehydrogenase complex to divert the pyruvate flux (final product of glycolysis) from oxidative phosphorylation towards aerobic glycolysis. Recently, we reported the role of PDK2 and PDK4 (PDK2/4) in platelet activation and arterial thrombosis. The regulatory role of PDKs in neutrophils and VT has not been explored. Aim: To test the hypothesis that PDK2/4 promotes NETosis and VT by promoting glycolysis in neutrophils. Methods: Double-deficient PDK2/4 -/- and wild-type (WT) mice were subjected to 48 hours of inferior vena cava stenosis to test the susceptibility to VT. In vitro , neutrophils were stimulated with Phorbol 12-myristate 13-acetate (PMA) and the glycolytic proton efflux rate (glycoPER) was measured using the Seahorse XF Analyzer. Results: The PDK2/4 -/- mice were less susceptible to DVT as measured by the primary outcome of reduced thrombus burden (weight, length and % incidence) and marker of NETs such as citrullinated histones (P&lt;0.05 vs WT). In the WT platelet aggregation assay mediated by PMA-stimulated WT or PDK2/4 -/- neutrophils, we observed reduced platelet aggregation evoked by PMA-stimulated PDK2/4 -/- neutrophils (P&lt;0.05 vs WT). Impaired aggregation was associated with reduced release of cathepsin G and elastase from PMA-stimulated PDK2/4 -/- neutrophils (P&lt;0.05 vs WT). Mechanistically, PMA-stimulated PDK2/4 -/- neutrophils exhibited reduced NETosis that was associated with decreased calcium mobilization and Erk1/2 phosphorylation (P&lt;0.05 vs WT), known contributors of NETosis. Furthermore, PMA-stimulated PDK2/4 -/- neutrophils displayed reduced glycoPER (P&lt;0.05 vs WT), suggesting reduced aerobic glycolysis. Conclusions: These findings for the first time demonstrate the regulatory role of PDK2/4 in NETosis and acute progression of VT.

Therapeutic Potential of Carica papaya Linn.: A Comprehensive Review of Its Pharmacological Properties and Health Benefits, with Emphasis on Dengue Fever Healing

For thousands of years, people have used various plant products, foods, spices, and herbs to treat and prevent illnesses. Sri Lankans have been using traditional and folk medicine to satisfy their basic health needs from the earliest days. Carica papaya Linn. (Caricaceae) is a commercially grown exotic plant in Sri Lanka. The entire plant, including the fruits both ripened and green, leaves, roots, peel, seed, and pulp, was used as medicine in traditional medicinal systems. Plant parts of Carica papaya Linn. were frequently used by ancient Sri Lankans to treat diabetes mellitus, hypertension, cancer, dengue fever, skin infections, renal disorders, and infections caused by bacteria, fungi, parasites, and viruses. Dengue fever is the most prevalent and significant arthropod-borne viral disease in humans, and it is extensively spread throughout Sri Lanka. Carica papaya Linn. extracts have been used to treat dengue patients to recover from its complications, which include thrombocytopenia, hemolysis, and leukopenia. Studies reveal that the papaya leaf extract can neutralize plasma with the dengue virus, reduce platelet aggregation, and increase the production of the enzyme ALOX12, which promotes platelet production. Moreover, the extract also upregulates the platelet-activating factor receptor (PTAFR) gene and inhibits serine proteases NS2B and NS3 involved in dengue virus replication. In this review, we have discussed extensively the ethnomedicinal and pharmacological properties of Carica papaya while highlighting its remarkable potency in healing dengue.

High platelet adrenergic activity and concomitant activation of the pituitary/medullar axis as alarming laboratory parameters in ACS survivors-the STRESS-AMI study.

Kinetics of stress-related biological parameters were determined in acute coronary syndrome (ACS) patients undergoing complex cardiovascular rehabilitation. We determined platelet functionality in the absence/presence of a selective alpha-2 adrenergic receptor inhibitor, atipemazole parallel with salivary cortisol levels at enrolment, and at 3- and 12-months follow-up in 75 ACS patients with percutaneous coronary intervention. Pharmacological/non-pharmacological secondary prevention methods have been efficiently applied. Baseline aggregometry indicated platelet hyperactivity, decreasing gradually and being significantly reduced late, at 12 months (p < 0.05). Cortisol levels followed similar kinetics (p < 0.05). Baseline epinephrine-induced aggregations (EIA) significantly correlated with most of the other platelet agonists, even at subsequent time-points. Patients with upper-quartile EIA at enrolment (EIA-UQ) had significantly higher ADP- and collagen-induced aggregations at enrolment, at 3- and 12-months follow-up as well, indicating that high adrenergic response in the acute phase is accompanied by general platelet hyperactivity and predicts sustained platelet activation. In the EIA-UQ group higher cardiac biomarker release, elevated C-reactive protein and cortisol levels, and lower baseline left ventricular ejection fraction were detected.Atipemazole significantly reduced platelet aggregation induced by several platelet agonists, being most potent and comparable to full in vitro P2Y12 inhibition on collagen-induced aggregations (p < 0.05), indicating that catecholamines might serve as promt/long-term modulators of platelet function. Despite effective CCR programme and dual antiplatelet therapy, prolonged activation of sympathetic neuroendocrine system and general platelet hyperactivity can be detected up to one year in ACS patients with high adrenergic platelet activity. Moreover, initial high adrenergic activity is accompanied by clinical parameters associated to increased cardiovascular risk, therefore early identification of these patients might support complex optimal long-term therapy.

Curcumin alleviates myocardial inflammation, apoptosis, and oxidative stress induced by acute pulmonary embolism by regulating microRNA-145-5P/insulin receptor substrate 1 axis.

The treatment of patients with acute pulmonary embolism (APE) is extremely challenging due to the complex clinical presentation and prognosis of APE related to the patient's hemodynamic status and insufficient arterial blood flow and right ventricular overload. Protective efficacy against cardiovascular diseases of curcumin, a common natural polyphenolic compound, which has antithrombotic properties and reduces platelet accumulation in the circulation by inhibiting thromboxane synthesis has been demonstrated. However, the direct effect of curcumin on APE has rarely been studied. Therefore, the present study aimed to investigate the therapeutic potential of curcumin in APE and associated myocardial injury to provide new insights into curcumin as a promising competitive new target for the treatment of APE. A suspension of 12 mg/kg microspheres was injected intravenously into rats. An APE rat model was built. Before modeling, intragastric 100 mg/kg curcumin was given, and/or lentiviral plasmid vector targeting microRNA-145-5p or insulin receptor substrate 1 (IRS1) was injected. Pulmonary artery pressure was measured to assess right ventricular systolic pressure (RVSP). Hematoxylin and eosin (H&E) staining was performed on liver tissues and myocardial tissues of APE rats. TUNEL (terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling) staining and immunohistochemical (IHC) staining were conducted to measure apoptosis and CyPA-CD147 expression in the myocardium, respectively. Inflammatory indices interleukin-1beta (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) were measured by ELISA in cardiac tissues. RT-qPCR and Western blot were performed to determine the expression levels of related genes. In addition, by dual luciferase reporter assay and RIP assay, the relationship between microRNA-145-5p and insulin receptor substrate 1 (IRS1) was confirmed. In results: curcumin improved APE-induced myocardial injury, reduced myocardial tissue edema, and thrombus volume. It attenuated APE-induced myocardial inflammation and apoptosis, as well as reduced lung injury and pulmonary artery pressure. Curcumin promoted microRNA-145-5p expression in APE rat myocardium. MicroRNA-145-5p overexpression protected against APE-induced myocardial injury, and microRNA-145-5p silencing abolished the beneficial effects of curcumin in APE-induced myocardial injury. IRS1 was targeted by microRNA-145-5p. IRS1 silencing attenuated APE-induced myocardial injury, and enhanced therapeutic effect of curcumin on myocardial injury in APE rats. In conclusion, curcumin alleviates myocardial inflammation, apoptosis, and oxidative stress induced by APE by regulating microRNA-145-5p/IRS1 axis.

Evaluating thrombosis risk and patient-specific treatment strategy using an atherothrombosis-on-chip model.

Platelets play an essential role in thrombotic processes. Recent studies suggest a direct link between increased plasma glucose, lipids, and inflammatory cytokines with platelet activation and aggregation, resulting in an increased risk of atherothrombotic events in cardiovascular patients. Antiplatelet therapies are commonly used for the primary prevention of atherosclerosis. Transitioning from a population-based strategy to patient-specific care requires a better understanding of the risks and advantages of antiplatelet therapy for individuals. This proof-of-concept study evaluates the potential to assess an individual's risk of forming atherothrombosis using a dual-channel microfluidic model emulating multiple atherogenic factors in vitro, including high glucose, high cholesterol, and inflammatory cytokines along with stenosis vessel geometry. The model shows precise sensitivity toward increased plasma glucose, cholesterol, and tumour necrosis factor-alpha (TNF-α)-treated groups in thrombus formation. An in vivo-like dose-dependent increment in platelet aggregation is observed in different treated groups, benefiting the evaluation of thrombosis risk in the individual condition. Moreover, the model could help decide the effective dosing of aspirin in multi-factorial complexities. In the high glucose-treated group, a 50 μM dose of aspirin could significantly reduce platelet aggregation, while a 100 μM dose of aspirin was required to reduce platelet aggregation in the glucose-TNF-α-treated group, which proves the model's potentiality as a tailored tool for customised therapy.

Bioactive Flavonoids in Protecting Against Endothelial Dysfunction and Atherosclerosis.

Atherosclerosis is a common cardiovascular disease closely associated with factors such as hyperlipidaemia and chronic inflammation. Among them, endothelial dysfunction serves as a major predisposing factor. Vascular endothelial dysfunction is manifested by impaired endothelium-dependent vasodilation, enhanced oxidative stress, chronic inflammation, leukocyte adhesion and hyperpermeability, endothelial senescence, and endothelial-mesenchymal transition (EndoMT). Flavonoids are known for their antioxidant activity, eliminating oxidative stress induced by reactive oxygen species (ROS), thereby preventing the oxidation of low-density lipoprotein (LDL) cholesterol, reducing platelet aggregation, alleviating ischemic damage, and improving vascular function. Flavonoids have also been shown to possess anti-inflammatory activity and to protect the cardiovascular system. This review focuses on the protective effects of these naturally-occuring bioactive flavonoids against the initiation and progression of atherosclerosis through their effects on endothelial cells including, but not limited to, their antioxidant, anti-inflammatory, anti-thrombotic, and lipid-lowering properties. However, more clinical evidences are still needed to determine the exact role and optimal dosage of these compounds in the treatment of atherosclerosis.

Smaart Criz: Sickle Cell Mechanisms of Activation, Adhesion, Rheology, and Thrombosis (SMAART) in Response to P-Selectin Inhibition

Sickle cell disease (SCD) pathophysiology involves uncontrolled inflammation, dysregulated coagulation, and adherence of erythrocytes, leukocytes, and platelets to endothelium, all contributing to disrupted rheology and ultimately vaso-occlusion. Crizanlizumab (Novartis), an FDA-approved humanized monoclonal antibody, binds to p-Selectin and blocks endothelial interactions with blood cells. The phase 2 SUSTAIN trial demonstrated a reduction in the median rate of pain crisis, as well as prolonged time to first and second crisis ( Ataga 2017). Not all participants benefited, however, nor have all treated patients achieved pain reduction in the post-marketing period. Paradoxical infusion-related pain has also been reported ( Kanter 2022). Baseline differences between responders, non-responders, and those suffering infusion-related pain remain uncharacterized. In January 2023, Novartis issued a preliminary update on the ongoing global crizanlizumab phase 3 STAND trial which indicated no statistically significant pain reduction with crizanlizumab therapy compared to placebo. A better understanding of patient suitability for the various disease modifying therapies for SCD would however be beneficial. Our center is a pilot site for a lab conducting an assay measuring flow adhesion of whole blood to P-selectin (FA-WB-Psel) utilizing a protein coated microfluidic chamber by Functional Fluidics. Previously published data identified a steady state reference range for FA-WB-Psel in non-SCD as well as SCD patients ( Pittman 2021). The SMAART Criz study aims to characterize downstream biological effects of crizanlizumab (FA-WB-Psel) and identify biomarkers with the potential to predict treatment response, with the goal of facilitating more individualized prescribing. This is an interim analysis of an investigator-initiated, prospective, IRB-approved, 18-week longitudinal study at the Children's Hospital of Michigan. Patients desiring crizanlizumab treatment were offered enrollment. Following informed consent, samples were obtained for FA-WB-Psel before and after each crizanlizumab dose. Flow adhesion of whole blood to vascular cell adhesion molecule-1 (FA-WB-VCAM) was assessed as a control substrate. Thromboelastography (TEG) and whole blood platelet aggregometry were performed to evaluate platelet function at baseline, week 6, and week 18. Patient reported response to treatment was used to measure response to therapy. As of August 2023, 7 patients have completed the study with a median age of 20 years (range 16-25 years; 4 female). Genotypes are HbSS (5), HbSC (1), and HbS-G-Philadelphia (1). Four of 7 patients self-reported clinical response to therapy (Table 1). Treatment was discontinued after 1st dose due to treatment-related acute pain in 2 participants, and after the 4th dose due to patient-reported worsening pain trend (Figure 1). Clinical responders had a median baseline FA-WB-Psel adhesion index of 86 cells/mm 2 (n=4, mean 106, range of 56-193). Clinical responders experienced a 65% reduction in FA-WB-Psel from baseline (mean 86) to the mean pre-infusion level calculated using visit 2 and 3 levels (p=0.05, later visits affected by dropout). Non-responders had a median baseline FA-WB-PSel of 49 cells/mm 2 (n=3, mean 46, range 13-75) with widely variable FA-WB-PSel responses (Fig. 1). The two patients with acute treatment-induced pain had the lowest baseline values at 13 and 49 cells/mm 2. No significant trends were observed in adhesion to a control substrate using FA-WB-VCAM. There was an overall decrease in both arachidonic acid (AA) and adenosine diphosphate (ADP) platelet aggregation over time (AA: 23.5 Ohms to 11.3 Ohms, p=0.254; ADP: 23.4 Ohms to 10.6 Ohms, p=0.036). Early indications from SMAART Criz are that administration of crizanlizumab decreases FA-WB-Psel immediately after infusion with continued decreases over time. Interim analysis suggests elevated baseline FA-WB-Psel may predict individuals with SCD likely to benefit from crizanlizumab, while normal FA-WB-Psel levels at baseline may predict non-response or even adverse reactions. This cohort showed an overall decrease in both AA and ADP aggregation, indicating reduced platelet aggregation following crizanlizumab treatment, a potential downstream biological change contributing to treatment effect (Table 1). Further investigation is warranted. Enrollment and analyses are ongoing.

Broad-spectrum ginsentides are principal bioactives in unraveling the cure-all effects of ginseng

Stress and illness connection is complex and involves multiple physiological systems. Panax ginsengs, reputed for their broad-spectrum “cure-all” effect, are widely prescribed to treat stress and related illnesses. However, the identity of ginseng's “cure-all” medicinal compounds that relieve stress remains unresolved. Here, we identify ginsentides as the principal bioactives that coordinate multiple systems to restore homeostasis in response to stress. Ginsentides are disulfide-rich, cell-penetrating and proteolytic-stable microproteins. Using affinity-enrichment mass spectrometry target identification together with in vitro, ex vivo and in vivo validations, we show that highly purified or synthetic ginsentides promote vasorelaxation by producing nitric oxide through endothelial cells via intracellular PI3K/Akt signaling pathway, alleviate α1-adrenergic receptor overactivity by reversing phenylephrine-induced constriction of aorta, decrease monocyte adhesion to endothelial cells via CD166/ESAM/CD40 and inhibit P2Y12 receptors to reduce platelet aggregation. Orally administered ginsentides were effective in animal models to reduce ADP-induced platelet aggregation, to prevent collagen and adrenaline-induced pulmonary thrombosis as well as anti-stress behavior of tail suspension and forced swimming tests in mice. Together, these results strongly suggest that ginsentides are the principal panacea compounds of ginsengs because of their ability to target multiple extra- and intra-cellular proteins to reverse stress-induced damages.