Antiplatelet Aggregation Activity Research Articles

Bioanalytical method development, in-vivo pharmacokinetic evaluation, ex-vivo platelet aggregation inhibition activity of a novel solid dispersion formulation of ticagrelor

BackgroundTicagrelor, a potential antithrombotic drug indicated for cardiovascular events with acute coronary syndrome, has been restricted from its oral use due to poor aqueous solubility. The present investigation aimed to develop validated bioanalytical method for the analysis of plasma samples for improving the oral bioavailability of Ticagrelor. Additionally, evaluation of the improved antiplatelet activity of the Ticagrelor formulation compared to the marketed formulation.MethodsA bioanalytical method was developed in rat plasma samples using the isocratic separation mode. Plasma samples were processed by liquid-liquid extraction and analyzed by using reverse phase HPLC. A validated method was used for evaluating the pharmacokinetic profile of the developed formulation and marketed formulation in Sprague Dawley rats. Additionally, the ex-vivo antiplatelet aggregation activity was evaluated.ResultsThe developed method was accurate and linear (100 ng−800 ng) to quantify the drug in plasma. An in-vivo pharmacokinetic study was conducted for formulation at 10 mg/kg and different pharmacokinetic parameters were evaluated. From the results, we observed∼64% enhancements in the oral bioavailability of the Ticagrelor relative to the marketed formulation. The developed formulation (SD1) showed more significant inhibition of ADP-induced platelet aggregation compared to the marketed ticagrelor (RLD) formulation.ConclusionIn conclusion, we have successfully developed a validated analytical method for estimating Ticagrelor plasma concentration. Additionally, our study successfully enhanced Ticagrelor's oral bioavailability, and the developed formulation has more significant inhibition of ADP-induced platelet aggregation relative to the marketed formulation, indicating its substantial therapeutic potential.

Screening and Verification of Blood-Activating Effective Component Group of Panax notoginseng Based on Spectrum-Effect Relationships.

Panax notoginseng (P. notoginseng) is one of the most famous natural medicines and widely used to promote blood circulation in health care. However, the active component group of P. notoginseng for activating blood is not clear. We aim to screen and validate the pharmacodynamic component group (PCG), which could exert the same blood-activating effect as P. notoginseng. To clarify the active components, the chemical components were determined by liquid chromatography-tandem mass spectrometry, and the fingerprint of P. notoginseng was established. Twenty candidate active monomers were selected through the spectrum-effect relationship analysis. Eleven active monomers, including Ginsenoside Rg1, Rb1, Rd, F1, Rh1, Rg2, Rb2, Rg3, and Rk1 and Notoginsenoside R1 and R2, were screened out as the PCG through validation by platelet aggregation test. Among them, the antiplatelet aggregation activity of Ginsenoside Rh1 was directly confirmed for the first time. The active component group could exert similar efficacy to the P. notoginseng extract invitro and invivo through the validation of invitro platelet aggregation test and the rats with cerebral ischemia. This study laid the foundation for the quality evaluation of P. notoginseng and provided a reference for the research on the material basis of the pharmacodynamics of other Chinese herbs.

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.

Design, Synthesis, and Anti-Inflammatory Activity Evaluation of Novel Indanone Derivatives for the Treatment of Vascular Dementia.

Vascular dementia (VaD) is a neurodegenerative disease resulting from cerebral vascular obstruction, leading to cognitive impairment, and currently lacks effective treatment options.Due to its complex pathogenesis, multi-target drug design (MTDLs) strategies are considered among the most promising therapeutic approaches. In this study, we designed and synthesized a series of novel indanone derivatives targeting targets related to vascular health and dementia. The results indicated that compound C5exhibited excellent acetylcholinesterase inhibitory activity (IC50= 1.16 ± 0.41 μM) and anti-platelet aggregation activity (IC50= 4.92 ± 0.10 μM) within ranges of 0.1-1000 μM and 0.03-300 μM, respectively, possibly mediated by molecular docking interactions. Furthermore, compound C5demonstrated protective effects on cells at concentrations ≤50 μM, significantly reducing the release of nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1β) in a concentration-dependent manner, showcasing its potent neuroinflammatory inhibitory effects. Anti-inflammatory therapies are regarded as effective strategies for treating VaD. Therefore, compound C5holds promise as a novel candidate drug for further investigation into the treatment of vascular dementia.

Biological Activity Evaluation of Phenolic Isatin-3-Hydrazones Containing a Quaternary Ammonium Center of Various Structures.

A series of new isatin-3-hydrazones bearing different ammonium fragments was synthesized by a simple and easy work-up reaction of Girard's reagents analogs with 1-(3,5-di-tert-butyl-4-hydroxybenzyl)isatin. All derivatives have been shown to have antioxidant properties. In terms of bactericidal activity against gram-positive bacteria, including methicillin-resistant strains of Staphylococcus aureus, the best compounds are 3a, 3e, and 3m, bearing octyl, acetal, and brucine ammonium centers, respectively. In addition, brucine and quinine derivatives 3l, and 3j exhibit platelet antiaggregation activity at the level of acetylsalicylic acid, and this series of isatin derivatives does not adversely affect the hemostasis system as a whole. Thus, all the obtained results can lay the groundwork for future pharmaceutical developments for the creation of effective antibacterial drugs with reduced systemic toxicity due to the presence of antioxidant properties.

Platelet antiaggregant activity of Hypericum perforatum extracts

BackgroundIn addition to its potential use as an antidepressant, different studies have shown that Hypericum perforatum (HP) can have antibacterial, antioxidant, and antiviral properties. Despite this potential, most of the therapeutic bioactivities attributed to HP need further scientific support. In a previous study we found an inhibitory effect of HP in platelet activation markers. So, in the present work we investigate the effect of HP in another aspect of platelet function, platelet aggregation. MethodsFirst, the effect of different concentrations of the total alcoholic extract of HP on platelet aggregation was studied in 9 healthy donors by aggregometry methods using collagen as agonist. After that, to obtain dose-effect curves, 3 experiments were carried out independently in a single individual using collagen, adenosine diphosphate and epinephrine as agonists. ResultsOur results reveal a marked inter-individual variability and a significant dose-dependent decrease of aggregation responses induced by collagen in the presence of HP extracts (mean of minimum inhibition: 8 % at a dose of 0.068 mg es/ml and mean of maximum inhibition: 43 % at a dose of 0.456 mg es/ml). With the results obtained it was possible to obtained a IC50 value of 0.34 mg es/ml. ConclusionsWe can conclude that HP has a dose-dependent inhibitory effect on platelet function (activation and aggregation responses), therefore, our results suggest that HP may be recognized as an herbal medicine with anti-platelet properties.

Use of Olives-derived Phytochemicals for Prevention and Treatment of Atherosclerosis: An Update.

Mediterranean diet is frequently associated with longevity and a lower incidence of adverse cardiovascular events because of the biological activities and health effects of olives - its key component. Olive oil, olive leaf extract, fruits and different by-products contain many bioactive components that exert anti-oxidant, anti-inflammatory and anti-apoptotic activities. In this review, we focus on the recent studies exploring molecular mechanisms underlying the cardioprotective properties of different olive oils, olive leave extracts, and specific micro-constituents (such as oleuropein, tyrosol, hydroxytyrosol and others) in vitro on rodent models and in clinical trials on human subjects. Particularly, hydroxytyrosol and oleuropein were identified as the major bioactive compounds responsible for the antioxidant, anti-inflammatory, anti-platelet aggregation and anti-atherogenic activities of olive oil. In total, the discussed results demonstrated a positive association between the consumption of olive oil and improvement in outcomes in atherosclerosis, diabetes, myocardial infarction, heart failure, hypertension and obesity.

Phenols, flavonoids and anthocyanins in Solanum lasiocarpum from Borneo: In vitro antioxidant activity and phytochemical profiling via LCMS Q-TOF

Phenols, flavonoids, and anthocyanins are compounds that reported play important roles in plant defence mechanism system. Antioxidant activity is mostly derived from these phytochemical groups, which have a wide range of pharmaceutical properties, including antimicrobial, antitumor, anti-inflammatory, antipyretic, anti-allergy, anti-fertility, hypoglycemic, anti-histamine, antioxidant, antiviral, analgesic, anti-ulcerogenic, nephroprotective, antidiabetic, immuno-secretory, cardiovascular, anti-platelet aggregation, antibacterial, anticancer, and hepatoprotective activities. However, these compounds in Solanum lasiocarpum from Borneo areas are remaining unclear. In this experiment, we performed comprehensive evaluation on effect of extraction solvents on phenols, flavonoids, and anthocyanin's contents and further on the scavenging activity (2,2-diphenyl-1-picrylhydrazyl-hydrate, DPPH; 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid), ABTS; and ferric-reducing antioxidant power, FRAP). High phenolic, flavonoid and anthocyanin contents be found in low polar solvent. Antioxidant assay showed acetone was higher activity with IC50 of 6.36 mg/mL compared to methanol (12.1 mg/mL) and hexane (17.8 mg/mL). Furthermore, liquid chromatography mass spectrometry quadrupole-time of flight (LCMS Q-TOF) mass spectrometer detected N-Acryloylglycine, butoctamide hydrogen succinate, eruberin B, emmotin A and N-Cyclohexanecarbonylpentadecylamine that important in natural polymers, serve as sleep disorders treatment agents, anti-fibrotic property, immunomodulatory activity, and act as differentiator between N-palmitoylethanolamine-hydrolyzing acid amidase (NPAA) compared to fatty acid amide hydrolase (FAAH), respectively. The limitation of this research is the assessment of antioxidant properties related to the polarity of the extraction solvent. Polar solvents may exhibit high scavenging activity, but phenolic compounds, flavonoids, and anthocyanins are found in higher concentrations in non-polar solvents. We encourage further investigation into phytochemical profiles due to the abundance from non-polar solvents.

Synthesis, Docking, and DFT Studies on Novel Schiff Base Sulfonamide Analogues as Selective COX-1 Inhibitors with Anti-Platelet Aggregation Activity.

Selective COX-1 inhibitors are preferential therapeutic targets for platelet aggregation and clotting responses. In this study, we examined the selective COX-1-inhibitory activities of four newly synthesized compounds, 10-13, along with their abilities to inhibit platelet aggregation against ADP and collagen. The target compounds 10-13 were synthesized using the conventional method, sonication, and microwave-assisted methods. Microanalytical and spectral data were utilized to elucidate the structures of the new compounds 10-13. Additionally, a spectral NMR experiment [NOESY] was conducted to emphasize the configuration around the double bond of the imine group C=N. The obtained results revealed no observed correlation between any of the neighboring protons, suggesting that the configuration at the C=N double bond is E. Biological results revealed that all the screened compounds 10-13 might serve as selective COX-1 inhibitors. They showed IC50 values ranging from 0.71 μM to 4.82 μM against COX-1 and IC50 values ranging from 9.26 μM to 15.24 μM against COX-2. Their COX-1 selectivity indices ranged between 2.87 and 18.69. These compounds show promise as promising anti-platelet aggregation agents. They effectively prevented platelet aggregation induced by ADP with IC50 values ranging from 0.11 μM to 0.37 μM, surpassing the standard aspirin with an IC50 value of 0.49 μM. Additionally, they inhibited the platelet aggregation induced by collagen with IC50 values ranging from 0.12 μM to 1.03 μM, demonstrating superior efficacy compared to aspirin, which has an IC50 value of 0.51 μM. In silico molecular modeling was performed for all the target compounds within the active sites of COX-1 and COX-2 to rationalize their selective inhibitory activities towards COX-1. It was found that the binding interactions of the designed compounds within the COX-1 active site had remained unaffected by the presence of celecoxib. Molecular modeling and DFT calculations using the B3LYP/6-31+G (d,p) level were performed to study the stability of E-forms with respect to Z-forms for the investigated compounds. A strong correlation was observed between the experimental observations and the quantum chemical descriptors.

Phenolic profile, cheminformatics, and antiplatelet aggregation activity of orange and purple sweet potato (Ipomoea batatas L.) storage roots

Sweet potatoes are rich in cardioprotective phytochemicals with potential anti-platelet aggregation activity, although this benefit may vary among cultivars/genotypes. The phenolic profile [HPLC-ESI(−)-qTOF-MS2], cheminformatics (ADMET properties, affinity toward platelet proteins) and anti-PA activity of phenolic-rich hydroalcoholic extracts obtained from orange (OSP) and purple (PSP) sweet potato storage roots, was evaluated. The phenolic richness [Hydroxycinnamic acids> flavonoids> benzoic acids] was PSP > OSP. Their main chlorogenic acids could interact with platelet proteins (integrins/adhesins, kinases/metalloenzymes) but their bioavailability could be poor. Just OSP exhibited a dose-dependent anti-platelet aggregation activity [inductor (IC50, mg.ml−1): thrombin receptor activator peptide-6 (0.55) > Adenosine-5′-diphosphate (1.02) > collagen (1.56)] and reduced P-selectin expression (0.75–1.0 mg.ml−1) but not glycoprotein IIb/IIIa secretion. The explored anti-PA activity of OSP/PSP seems to be inversely related to their phenolic richness. The poor first-pass bioavailability of its chlorogenic acids (documented in silico) may represent a further obstacle for their anti-PA in vivo.

Discovery of 2,3-Dihydro[1,4]dioxino[2,3-g]benzofuran Derivatives as Protease Activated Receptor 4 (PAR4) Antagonists with Potent Antiplatelet Aggregation Activity and Low Bleeding Tendency.

Patients with arterial embolic disease have benefited greatly from antiplatelet therapy. However, hemorrhage risk of antiplatelet agents cannot be ignored. Herein, we describe the discovery of 2,3-dihydro[1,4]dioxino[2,3-g]benzofuran compounds as novel PAR4 antagonists. Notably, the isomers 36 and 37 with the chemotype of phenoxyl methylene substituted on the 2,3-dihydro-1,4-dioxine ring exhibited potent in vitro antiplatelet activity (IC50 = 26.13 nM for 36 and 14.26 nM for 37) and significantly improved metabolic stability in human liver microsomes (T1/2 = 97.6 min for 36 and 11.1 min for BMS-986120). 36 also displayed good oral PK profiles (mice: T1/2 = 7.32 h and F = 45.11%). Both of them showed overall potent ex vivo antiplatelet activity at concentrations of 6 and 12 mg/kg, with no impact on the coagulation system and low bleeding liability. Our work will facilitate development of novel PAR4 antagonists as a safer therapeutic option for arterial embolism.

Design, synthesis, and evaluation of the novel ozagrel-paeonol codrug with antiplatelet aggregation activities as a potent anti-stroke therapeutic agent.

Introduction: Ischemic stroke is the second most common chronic disease worldwide and is associated with high morbidity and mortality. Thromboembolism and platelet aggregation are the most characteristic features of stroke. Other than aspirin, no standard, accepted, or effective treatment for acute ischemic stroke has been established. Consequently, it is essential to identify novel therapeutic compounds for this condition. Methods: In this study, novel ozagrel/paeonol-containing codrugs were synthesized and characterized using 1H-NMR, 13C-NMR, and mass spectroscopy. Their antiplatelet aggregation activity was evaluated, with compound PNC3 found to exhibit the best effect. Subsequently, studies were conducted to assess its neuroprotective effect, pharmacokinetic properties and model its binding mode to P2Y12 and TXA2, two proteins critical for platelet aggregation. Results: The results indicated that PNC3 has good bioavailability and exerts protective effects against oxygen-glucose deprivation injury in PC12 cells. Molecular docking analysis further demonstrated that the compound interacts with residues located in the active binding sites of the target proteins. Conclusion: The codrugs synthesized in this study display promising pharmacological activities and have the potential for development as an oral formulation.

Ginkgolides with anti-PAF activity from Ginkgo biloba L.

Four undescribed ginkgolides, including two rare sesquiterpene ginkgolides (compounds 1 and 2) and two diterpenoid ginkgolides (compounds 3 and 4), were isolated from Ginkgo biloba L. The structures of these four ginkgolides were identified based on extensive spectroscopic analysis, DP4+ probability analysis and X-ray diffraction. Compounds 1 and 2 exhibited excellent antiplatelet aggregation activities with IC50 values of 1.20 ± 0.25 and 4.11 ± 0.34 μM, respectively.

Metabolomics and network pharmacology reveal the mechanism of antithrombotic effect of Asperosaponin VI

Dipsaci Radix may possess antithrombotic properties, and one of its primary active ingredients is Asperosaponin VI. However, the antithrombotic effects and pharmacological mechanisms of Asperosaponin VI remain unclear. An in vivo experimental study has demonstrated the antithrombotic activity of Asperosaponin VI. Asperosaponin VI also exhibits anticoagulant properties. Asperosaponin VI significantly hindered collagen adrenergic-induced acute pulmonary thrombosis in mice and enhanced their survival rate. This hinders the formation of acute pulmonary embolisms induced by adenosine diphosphate (ADP) and decreases recovery time. A comprehensive strategy that combines metabolomics, network pharmacology, molecular docking, and experimental validation has the potential to reveal the antithrombotic mechanisms of Asperosaponin VI. Metabolomic evidence suggests that Asperosaponin VI may influence platelet aggregation and the production of anti-inflammatory metabolites through the regulation of pathways such as phenylalanine and arachidonic acid metabolism, thereby inhibiting thrombosis. Network pharmacology identified the pharmacological targets of Asperosaponin VI and indicated that it treats thrombi by partially regulating the signaling pathways related to inflammation and platelet aggregation. Asperosaponin VI showed strong binding affinity for F2, PTPRC, JUN, STAT3, SRC, AKT1. The antiplatelet aggregation activity of Asperosaponin VI was validated based on the metabolomic and network pharmacology results. Asperosaponin VI inhibits platelet aggregation induced by ADP, AA, and collagen. Therefore, Asperosaponin VI exerts antithrombotic effects through antiplatelet aggregation. Therefore, Asperosaponin VI is a promising antithrombotic agent.

Mudanpioside C Discovered from Paeonia suffruticosa Andr. Acts as a Protein Disulfide Isomerase Inhibitor with Antithrombotic Activities.

Paeonia suffruticosa Andr. is a well-known landscape plant worldwide and also holds significant importance in China due to its medicinal and dietary properties. Previous studies have found that Cortex Moutan (CM), the dried root bark of P. suffruticosa, showed antiplatelet and cardioprotective effects, although the underlying mechanism and active compounds remain to be revealed. In this study, protein disulfide isomerase (PDI) inhibitors in CM were identified using a ligand-fishing method combined with the UHPLC-Q-TOF-MS assay. Further, their binding sites and inhibitory activities toward PDI were validated. The antiplatelet aggregation and antithrombotic activity were investigated. The results showed that two structurally similar compounds in CM were identified as the inhibitor for PDI with IC50 at 3.22 μM and 16.73 μM; among them Mudanpioside C (MC) is the most effective PDI inhibitor. Molecular docking, site-directed mutagenesis, and MST assay unequivocally demonstrated the specific binding of MC to the b'-x domain of PDI (Kd = 3.9 μM), acting as a potent PDI inhibitor by interacting with key amino acids K263, D292, and N298 within the b'-x domain. Meanwhile, MC could dose-dependently suppress collagen-induced platelet aggregation and interfere with platelet activation, adhesion, and spreading. Administration of MC can significantly inhibit thrombosis formation without disturbing hemostasis in mice. These findings present a promising perspective on the antithrombotic properties of CM and highlight the potential application of MC as lead compounds for targeting PDI in thrombosis therapy.

Anti-platelet aggregation activities of different grades of Angelica sinensis and their therapeutic mechanisms in rats with blood deficiency: insights from metabolomics and lipidomics analyses.

In traditional Chinese medicine, the radix of Angelica sinensis (Oliv.) Diels (RAS) is mainly used to replenish and invigorate the blood circulation. This study investigated anti-platelet aggregation activities were used by New Zealand rabbits, and high-performance liquid chromatography data were obtained to determine the spectrum-effect relationship for different commercial grades of RAS. Plasma and urine metabolites were examined using ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry-based metabolomics to elucidate the mechanisms underlying the role of these metabolites in a rat model of blood deficiency (BD). Plasma and spleen metabolites were additionally examined using ultra-performance liquid chromatography plus Q-Exactive tandem mass spectrometry-based lipidomics to clarify the mechanisms of RAS in treating BD. The third grade of RAS exhibited the best activity in replenishing and invigorating blood in vitro and in vivo. Ferulic acid, ligustilide, senkyunolide I, uridine, and guanine are quality markers of anti-platelet aggregation activity. Based on the metabolomics results, 19 potential biomarkers were screened in plasma, and 12 potential metabolites were detected in urine. In lipidomics analyses, 73 potential biomarkers were screened in plasma, and 112 potential biomarkers were screened in the spleen. RAS may restore lipid metabolism by regulating disorders of glycerophospholipid and sphingolipid metabolism, the tricarboxylic acid cycle, amino acid metabolism (thereby improving energy metabolism), and arachidonic acid metabolism (thereby promoting blood circulation). These results provide a deeper understanding of the effects of different grades of RAS and a scientific reference for the establishment of grading standards and for the clinical use of RAS.

Cathelicidin-HG Alleviates Sepsis-Induced Platelet Dysfunction by Inhibiting GPVI-Mediated Platelet Activation.

Platelet activation contributes to sepsis development, leading to microthrombosis and increased inflammation, which results in disseminated intravascular coagulation and multiple organ dysfunction. Although Cathelicidin can alleviate sepsis, its role in sepsis regulation remains largely unexplored. In this study, we identified Cath-HG, a novel Cathelicidin from Hylarana guentheri skin, and analyzed its structure using nuclear magnetic resonance spectroscopy. The modulatory effect of Cath-HG on the symptoms of mice with sepsis induced by cecal ligation and puncture was evaluated invivo, and the platelet count, degree of organ damage, and microthrombosis were measured. The antiplatelet aggregation activity of Cath-HG was studied invitro, and its target was verified. Finally, we further investigated whether Cath-HG could regulate thrombosis invivo in a FeCl3 injury-induced carotid artery model. The results showed that Cath-HG exhibited an α-helical structure in sodium dodecyl sulfate solution and effectively reduced organ inflammation and damage, improving survival in septic mice. It alleviated sepsis-induced thrombocytopenia and microthrombosis. Invitro, Cath-HG specifically inhibited collagen-induced platelet aggregation and modulated glycoprotein VI (GPVI) signaling pathways. Dot blotting, enzyme-linked immunosorbent assay, and pull-down experiments confirmed GPVI as the target of Cath-HG. Molecular docking and amino acid residue truncations/mutations identified crucial sites of Cath-HG. These findings suggest that GPVI represents a promising therapeutic target for sepsis, and Cath-HG may serve as a potential treatment for sepsis-related thrombocytopenia and thrombotic events. Additionally, identifying Cath-HG as a GPVI inhibitor provides insights for developing novel antithrombotic therapies targeting platelet activation mediated by GPVI.

Novel 1,3,4-oxadiazole hybrids of 3-n-butylphthalide derivatives as potential anti-ischemic stroke agents

In continuation of our program to search for novel potential anti-ischemic stroke agents, a series of 1,3,4-oxadiazole and sulfoxide hybrids of phthalide derivatives was designed and synthesized in this study to evaluate their anti-ischemic stroke activity. Among them, compounds 5b, 5d, 5 l, and 5 m exhibited excellent inhibitory effects on platelet aggregation induced by adenosine diphosphate (ADP) and arachidonic acid (AA). In particular, compound 5b possessed considerable antithrombotic activity in animal models, as demonstrated by the effective alleviation of carrageenan-induced and FeCl3-induced thrombosis in tail and carotid arteries, respectively. Notably, intraperitoneal administration of compound 5b could better protect the brain from injury caused by ischemia/reperfusion in rats compared with precursor 3-n-butylphthalide. Further pharmacokinetics, liver microsomal stability, and PAMPA-BBB assays also indicated that compound 5b had relatively high bioavailability, metabolic stability, and BBB permeability. Moreover, compound 5b showed a safety profile that was superior to the clinical drugs clopidogrel, aspirin, and 3-n-butylphthalide in the mouse-tail bleeding assay. Finally, molecular docking predicted that the potential target of the antiplatelet aggregation activity of compound 5b was P2Y12 receptor. This research provides a novel candidate compound for the treatment of ischemic stroke.

Anticancer and Antiphytopathogenic Activity of Fluorinated Isatins and Their Water-Soluble Hydrazone Derivatives.

A series of new fluorinated 1-benzylisatins was synthesized in high yields via a simple one-pot procedure in order to explore the possible effect of ortho-fluoro (3a), chloro (3b), or bis-fluoro (3d) substitution on the biological activity of this pharmacophore. Furthermore, the new isatins could be converted into water-soluble isatin-3-hydrazones using their acid-catalyzed reaction with Girard's reagent P and its dimethyl analog. The cytotoxic action of these substances is associated with the induction of apoptosis caused by mitochondrial membrane dissipation and stimulated reactive oxygen species production in tumor cells. In addition, compounds 3a and 3b exhibit platelet antiaggregation activity at the level of acetylsalicylic acid, and the whole series of fluorine-containing isatins does not adversely affect the hemostasis system as a whole. Among the new water-soluble pyridinium isatin-3-acylhydrazones, compounds 7c and 5c,e exhibit the highest antagonistic effect against phytopathogens of bacterial and fungal origin and can be considered useful leads for combating plant diseases.

An innovative processing driven efficient transformation of rare ginsenosides enhances anti-platelet aggregation potency of notoginseng by integrated analyses of processing-(chemical) profiling-pharmacodynamics

Ethnopharmacological relevancePanax notoginseng (Burk.) F. H. Chen, a valuable Chinese herb medicine, shows a characteristic bi-directional regulation of hemostasis and activating blood circulation with ginsenosides as the predominant bioactive compounds and is a typical representative of “processing triggered heteropotency”. Aim of the studyProcessing triggered heteropotency, one of the unique theories and practices in traditional Chinese medicine, refers to that the processing will lead to change in physical and chemical properties, and eventually disparate efficacy of the crude drugs, yet the optimum process and underlying mechanism remains unclear. In this study, using Panax notoginseng (PN) as a representative sample, a processing-(chemical) profiling-pharmacodynamics (3-P) relationship was proposed to investigate the processing mechanism of PN. Materials and methodsFirstly, a temperature programmed steaming process was designed to evaluate the steaming triggered chemical transformation of triterpene saponins and the corresponding enhancement in anti-platelet aggregation activity. The steaming process was programed from the conventional 100 °C–150 °C in a time course of 0–12 h, aiming to achieve the maximized conversion of rare ginsenosides (RGs), and dynamic profile of ginsenosides were constructed by a UPLC-Q-TOF-MS/MS analysis. Then, a processing-(chemical) profiling-pharmacodynamics (3-P) relationship was assessed by using the grey relational analysis (GRA) and orthogonal projections to latent structures (OPLS), and validated by bioactive fraction of 140 °C steamed PN. Subsequently, the P2Y12-ligand binding affinity of potential candidates was analyzed by molecular docking. Finally, the dynamic changes of ginsenosides during steaming of SPN were quantitatively detected by UPLC-QQQ-MS/MS. ResultsA total of 48 differential ginsenosides were characterized and monitored including the primary and secondarily transformed saponins. The higher temperature steaming especially at 140 °C induces not only the predominant production of the RGs, but also the stronger anti-platelet aggregation activity. The 3-P relationship showed the fraction (3) of 140 °C steamed PN rich in RGs exhibits the most predominant efficacy, in which, a series of RGs including ginsenosides Rg5, Rk1, 20(S/R)-Rg3 were proven to be potent components. Molecular docking analysis suggested that ginsenosides Rg5 and Rk1 showed more strong interaction with the platelet P2Y12 receptor. Quantitative analysis found 140 °C-2h PN possessed highest contents of Rk1 and Rg5 and total RGs. ConclusionsThe integrated 3-P strategy uncovered the promising ginsenosides with anti-platelet effect, thereby revealing the material basis of PN steaming, which could provide a new enlightenment for the investigation of processing mechanism of traditional Chinese medicines.