Multimodal integrated strategy for the discovery and identification of antiplatelet aggregation Q-markers in Paris polyphylla var. yunnanensis

To enhance the quality evaluation and control of traditional Chinese medicine (TCM) and ensure the safety and efficacy of clinical medication, it is imperative to establish a comprehensive quality assessment method aligned with TCM efficacy. This study uses a representative Chinese medicine with multi-origin and multi-efficacy, Paris polyphylla var. yunnanensis (PY), as an illustrative example. Surprisingly, despite the high fingerprint similarity among the 12 batches of PY samples collected from various regions in Yunnan, a notable variation in the composition and content of components was observed. The chromatographic analysis identified seven common peaks, namely, polyphyllin I, polyphyllin II, polyphyllin V, polyphyllin VI, polyphyllin VII, polyphyllin H, and polyphyllin D. In the bioactivity evaluation, an in vitro antiplatelet aggregation model induced by adenosine diphosphate was established, showcasing excellent stability. The maximum antiplatelet aggregation inhibition rate for all PY samples consistently remained stable at 73.1%-99.1%. However, the 50% inhibitory concentration (IC50 ) values exhibited a range from 1.615 to 18.200 mg/mL. This approach not only meets high-throughput screening requirements but also demonstrates remarkable discrimination. The results of chemical and bioactivity evaluations were analyzed using hierarchical cluster analysis and canonical correlation analysis. Polyphyllin I, polyphyllin II, polyphyllin VII, polyphyllin H, and polyphyllin D were identified as the Q-markers for antiplatelet aggregation in PY samples. Validation of the bioactivity for these monomer components aligned with the previously mentioned findings. Notably, this study established a spectrum-effect model for PY samples, enhancing the scientific robustness of the quality evaluation method. Furthermore, these findings offer valuable research insights for improving the quality assessment of other TCMs.

Potential antithrombotic effect of two new phenylpropanoid sucrose esters and other secondary metabolites of Canna indica L. rhizome

Canna indica L. has been traditionally used to treat various diseases. Based on previously reported antithrombotic effect for this plant, two new phenylpropanoid sucrose esters (canindicoside A (1) and canindicoside B (2)) and seven known compounds: nepetoidin B (3), caffeic acid (4), ferulic acid (5), (R)-(+)-rosmarinic acid (6), isorinic acid (7), (S)-(-)-rosmarinic acid (8) and (S)-(-)-rosmarinic acid methyl ester (9) were isolated from the ethyl acetate extract. Compounds were elucidated by NMR and MS spectroscopic methods. The antiplatelet effect was evaluated using turbidimetric method. Anticoagulant activity was examined by measuring activated partial thromboplastine time (APTT), prothrombin time, and thrombine time (TT). It was shown for the first time that both new phenylpropanoid sucrose esters 1 and 2, 7 and 9 displayed dose-dependent antiplatelet effects. 2 and 9 had the highest inhibitory activity on both adenosine diphosphate (ADP)- and collagen-induced platelet aggregation. Moreover, 1, 7 and 9 also exhibited anticoagulant activity. At 0.4 mg/mL, both 1 and 7 prolonged APTT compared to the negative control (p < 0.05), suggesting the possible inhibitory impact on the intrinsic coagulation pathway. Moreover, 9 at 0.4 mg/mL exerted higher TT values than the negative control (p < 0.05). C. indica and its bioactive phytochemicals are potential candidates for development of anti-thrombosis therapy.

Design, synthesis, and anticancer evaluation of N6 -hydrazone purine derivatives with potential antiplatelet aggregation activity

In our research on novel anticancer agents, a series of N⁶ -hydrazone purine derivatives were designed and synthesized by analysis of a pharmacophore model for ATP-competitive inhibitors. The activities screening results showed that N⁶ -hydrazone purine derivatives 21 and 26 not only showed potential antiproliferative activity against the A549 and MCF-7 cell lines comparable to Vandetanib as a positive control but also had moderate antiplatelet aggregation activity. In order to investigate the possible targets, a molecular docking study was carried out on the fourteen kinases associated with anticancer and antiplatelet aggregation activities. The results indicated that compounds 21 and 26 had the potential activity to target VEGFR-2, PI3Kα, EGFR, and HER2 kinases. The inhibition of the kinases assay showed that compound 26 could target VEGFR-2, PI3Kα, and EGFR (IC₅₀  = 0.822, 3.040 and 6.625 μM). All results indicated that compound 26 will be an encouraging framework as potential new multi-target anticancer agent with potential antiplatelet aggregation activity.

Chemical Constituents and Bioactive Principles from the Mexican Truffle and Fermented Products of the Derived Fungus Ustilago maydis MZ496986

To look in-depth into the traditional Mexican truffle, this study investigated the phytochemical and pharmacological properties of field-collected corn galls and the fermentate of its pathogen Ustilago maydis MZ496986. Here, we established the chemical profiles of both materials via the gradient HPLC-UV method and successfully identified six previously unreported chemical entities, ustilagols A-F (1-6), and 17 known components. Compounds 3, 5, and 9 exhibited potent nitric oxide production inhibitory activities in murine brain microglial BV-2 cells (IC₅₀ = 6.7 ± 0.5, 5.8 ± 0.9, and 3.9 ± 0.1 μM) without cytotoxic effects. DIMBOA (9) also attenuates lipopolysaccharide (LPS)-stimulated NF-κB activation in RAW 264.7 macrophages (IC₅₀ = 58.1 ± 7.2 μM). Ustilagol G (7) showed potent antiplatelet aggregation in U46619-stimulated human platelets (IC₅₀ = 16.5 ± 5.3 μM). These findings highlighted the potential of corn galls and U. maydis MZ496986 fermentate as functional foods for improving inflammation-related discomforts and vascular obstruction.

Natural Products in Cardiovascular Diseases: The Potential of Plants from the Allioideae Subfamily (Ex-Alliaceae Family) and Their Sulphur-Containing Compounds

Cardiovascular diseases (CVDs) are the leading cause of mortality worldwide and, together with associated risk factors such as diabetes, hypertension, and dyslipidaemia, greatly impact patients' quality of life and health care systems. This burden can be alleviated by fomenting lifestyle modifications and/or resorting to pharmacological approaches. However, due to several side effects, current therapies show low patient compliance, thus compromising their efficacy and enforcing the need to develop more amenable preventive/therapeutic strategies. In this scenario, medicinal and aromatic plants are a potential source of new effective agents. Specifically, plants from the Allioideae subfamily (formerly Alliaceae family), particularly those from the genus Allium and Tulbaghia, have been extensively used in traditional medicine for the management of several CVDs and associated risk factors, mainly due to the presence of sulphur-containing compounds. Bearing in mind this potential, the present review aims to gather information on traditional uses ascribed to these genera and provide an updated compilation of in vitro and in vivo studies validating these claims as well as clinical trials carried out in the context of CVDs. Furthermore, the effect of isolated sulphur-containing compounds is presented, and whenever possible, the relation between composition and activity and the mechanisms underlying the beneficial effects are pointed out.

Inhibitory Mechanisms of Lusianthridin on Human Platelet Aggregation

Lusianthridin is a phenanthrene derivative isolated from Dendrobium venustum. Some phenanthrene compounds have antiplatelet aggregation activities via undefined pathways. This study aims to determine the inhibitory effects and potential mechanisms of lusianthridin on platelet aggregation. The results indicated that lusianthridin inhibited arachidonic acid, collagen, and adenosine diphosphate (ADP)-stimulated platelet aggregation (IC₅₀ of 0.02 ± 0.001 mM, 0.14 ± 0.018 mM, and 0.22 ± 0.046 mM, respectively). Lusianthridin also increased the delaying time of arachidonic acid-stimulated and the lag time of collagen-stimulated and showed a more selective effect on the secondary wave of ADP-stimulated aggregations. Molecular docking studies revealed that lusianthridin bound to the entrance site of the cyclooxygenase-1 (COX-1) enzyme and probably the active region of the cyclooxygenase-2 (COX-2) enzyme. In addition, lusianthridin showed inhibitory effects on both COX-1 and COX-2 enzymatic activities (IC₅₀ value of 10.81 ± 1.12 µM and 0.17 ± 1.62 µM, respectively). Furthermore, lusianthridin significantly inhibited ADP-induced suppression of cAMP formation in platelets at 0.4 mM concentration (p < 0.05). These findings suggested that possible mechanisms of lusianthridin on the antiplatelet effects might act via arachidonic acid-thromboxane and adenylate cyclase pathways.

Isolation and Characterization of CD39-like Phosphodiesterase (Cc-PDE) from Cerastes cerastes Venom: Molecular Inhibitory Mechanism of Antiaggregation and Anticoagulation

BACKGROUND

Cerastes cerastes venom contains several bioactive proteins with inhibitory potential of platelet aggregation and blood coagulation.

OBJECTIVE

The current study deals with purification, characterization and determination of structural properties of Cc-PDE, the first phosphodiesterase from Cerastes cerastes venom.

MATERIAL AND METHODS

The purification process consists of three successive chromatographies including G75-Sephadex size exclusion, DEAE exchange chromatography and affinity using Sildenafil as a main PDEs' specific inhibitor. The amino acid sequence of purified Cc-PDE was determined by liquid chromatography coupled off line to MALDI-TOF/TOF. Modeling and structural features were obtained using several bioinformatics tools. In vivo and in vitro antiplatelet aggregation and anticoagulant assays were performed.

RESULTS

Cc-PDE (73 506.42 Da) is a 654-residue single polypeptide with 1-22 signal peptide and it is characterized by the presence of predominant basic amino acids suitable to alkaline pI (8.17). Cc-PDE structure is composed of β-strands (17%) and α-helices (24%) and it shares a high identity with homologous snake venom PDEs. Cc-PDE hydrolyzes both Bis-p-nitrophenyl phosphate (Km = 2.60 ± 0.95 mM, Vmax = 0.017 ± 0.002569 μmol.min-1) and p-nitrophenyl phosphate (Km = 7.13 mM ± 0.04490 mM, Vmax = 0.053 ±0.012 μmol.min-1). Cc-PDE prevents ADP- and ATP-induced platelet aggregation by hydrolyzing ADP and ATP, reducing surface P-selectin expression and attenuating platelet function. In addition, Cc-PDE inhibits coagulation factors involved in the intrinsic pathway demonstrated by a significant prolongation of activated partial thromboplastin time and in vivo long-lasting anticoagulation.

CONCLUSION

The obtained results revealed that Cc-PDE may have a therapeutic potential and could be a remedy for thromboembolic diseases as an alternative of anticoagulant and antiplatelet aggregation chemical origins.

Effect of ACG-1, an Extract Blend of Angelica gigas, Cynanchum wilfordii, and Ginkgo biloba, on Blood Circulation Improvement Via Antiplatelet Aggregation and Antihyperlipidemia

Thrombosis causes poor blood circulation, which may lead to several cardiovascular disorders. Antiplatelet aggregation and antihyperlipidemia are the key processes that improve blood circulation. The antiplatelet aggregation and antihyperlipidemic effects of ACG-1, a mixture of Angelica gigas, Cynanchum wilfordii, and Ginkgo biloba extracts, were investigated in this study. The antiplatelet aggregation activity of ACG-1 was determined by studying its effects on collagen-induced platelet aggregation in human platelet-rich plasma (PRP). In addition, the effects of ACG-1 were investigated in a thromboembolism mouse model. The high-fat diet (HFD)-fed mouse model was used to investigate the antihyperlipidemic effects of ACG-1 and western blotting assay was performed to elucidate its mechanism of action. It was observed that ACG-1 significantly inhibited platelet aggregation in human PRP. Furthermore, ACG-1 showed protective effects in a thromboembolism mouse model induced by administering a mixed collagen and epinephrine intravenous injection. Oral administration of ACG-1 also significantly ameliorated blood lipid profiles in the HFD-fed mouse model. In conclusion, ACG-1 should be considered a powerful functional food to improve blood circulation.

Synthesis of phthalide derivatives and evaluation on their antiplatelet aggregation and antioxidant activities

As part of our continuing efforts to discover structurally interesting bioactive phthalide derivatives, 23 of them with a structure incorporating thiophen or halogens were designed and synthesized, 17 of which are previously unreported. In vitro antiplatelet aggregation activity screening showed that 14b could significantly inhibit platelet aggregation induced by arachidonic acid, compared with edaravone (p < 0.01). Meanwhile, oxidative damage models using SH-SY5Y and PC12 cells induced by H₂O₂ were built to evaluate the antioxidant activity of the phthalide derivatives. In SH-SY5Y cells, compared with aspirin, 1a significantly increased the relative cell survival rate (p < 0.05). Compared with edaravone, 1a (p < 0.01) and 15b (p < 0.05) significantly increased the relative cell survival rate. In PC12 cells, 1a (p < 0.01), 15b (p < 0.01), and 12a (p < 0.05) remarkably increased the cell survival rate compared with edaravone. The present study identified lead structures to develop potential anti-ischemic stroke agents.

Severe Japanese encephalitis with multiple intracranial hemorrhages: A case report

RATIONALE

Intracranial hemorrhage occurs infrequently in Japanese encephalitis (JE), and even less frequently with hemorrhage occurring twice. In this report, we describe the clinical features and outcomes of a patient with confirmed JE combined with hemorrhage twice.

PATIENT CONCERNS

The patient, a 71-year-old Asian woman, was admitted to the hospital with symptoms of hemiplegia following fever and diarrhea. Soon her condition worsened and a decreased level of consciousness, respiratory failure, and paralysis of extremities occurred.The brain diffusion-weighted imaging sequence showed suspicious abnormal signals in bilateral thalami. Japanese encephalitis virus immunoglobulin M antibody was detected in her serum and cerebrospinal fluid samples, so the patient was diagnosed with JE. During treatment, her condition became aggravated and the brain computed tomography (CT) scan showed multiple lobar hemorrhages. One month later, the multiple lobar hemorrhages occurred again, as observed by a brain CT scan.

DIAGNOSIS

JE with multiple intracranial hemorrhages.

INTERVENTIONS

The patient was treated comprehensively, including surgery, lowering her intracranial pressure and ventilator-assisted breathing.

OUTCOMES

One month later, the patient underwent another surgical procedure for intracranial hemorrhage and suffered a serious neurological disorder.

LESSONS

Severe intracranial hemorrhage may occur in elderly patients with JE, especially in those with poor vascular condition. Therefore, when treating such patients, great caution, as well as early detection and prevention, should be taken in case of the occurrence of severe intracranial hemorrhage.

Clinical Evaluation of the Tolerability, Pharmacokinetics, and Inhibition of Platelet Aggregation of Eptifibatide in Healthy Chinese Subjects

The present study aimed to evaluate the pharmacokinetic properties and antiplatelet aggregation activity of eptifibatide in healthy Chinese subjects. Eptifibatide (180 μg/kg) was administrated by 2 bolus injections 10 minutes apart, followed by a 2.0 μg/kg/min infusion for 24 hours. The eptifibatide pharmacokinetic and antiplatelet aggregation activities were evaluated using nonlinear mixed-effects modeling and noncompartmental analysis. Safety assessments included adverse events, hematology, and biochemistry tests. Twelve Chinese healthy subjects were enrolled and completed the study. Steady-state concentrations were achieved at 0.5 to 24 hours after dosing. The median time to maximum concentration was 13 minutes, and the mean terminal elimination half-life was 148.19 minutes. The effective inhibition of platelet aggregation (<20% platelet aggregation) occurred by 3 minutes after starting dosing to 4 hours after termination of the infusion. Eptifibatide concentrations were fitted with a 3-compartment model, and the typical value of clearance was 0.11 L/min, with no significant covariates found. Three mild adverse events were detected in the study. Eptifibatide displays high sensitivity and excellent tolerability in healthy Chinese subjects. The dosage of eptifibatide recommended on the label for whites can effectively inhibit platelet aggregation.

Comparison of expression optimization of new derivative of staphylokinase (SAK-2RGD-TTI) with the rSAK

Staphylokinase (SAK) is a promising thrombolytic agent for the treatment of patients suffering from blood-clotting disorders. To increase the potency of SAK and to minimize vessel reocclusion, a new construct bearing SAK motif fused to tsetse thrombin inhibitor (TTI) via a 20-amino acid linker with 2 RGD (2 × arginine-glycine-aspartic acid inhibiting platelet aggregation via attachment to integrin receptors of platelet) was codon optimized and expressed comparatively in Pichia pastoris GS115 as a Mut⁺ strain and KM71H as a Mut^s strain. Fusion protein was optimized in terms of best expression condition and fibrinolytic activity and compared with the rSAK. Expression level of the designed construct reached up to 175 mg/L of the culture medium after 72-hr stimulation with 2.5% methanol and remained steady for 3-4 days. The highest expression was obtained at the range of 2-3% methanol. The SAK-2RGD-TT (relative activity >82%) was more active at 25-37 °C than rSAK (relative activity of 93%). Further, it showed relative activity >80% at pH ranges of 7-9. Western blot analysis showed two bands of nearly 27 and 24 kDa at ratio of 5 to 3, respectively. The specific fibrinolytic activity of the SAK-2RGD-TTI was measured as 8,269 U/mg, and 19,616 U/mg for the nonpurified and purified proteins, respectively. Deglycosylation by using tunicamycin in culture medium resulted in higher fibrinolytic activity of SAK-2RGD-TTI (2.2 fold). Consequently, compared to the rSAK, at the same equimolar proportion, addition of RGD and TTI fragments could increase fibrinolytic activity. Also, P. pastoris can be considered as an efficient host for overexpression of the soluble SAK-2RGD-TTI with high activity without requiring a complicated purification procedure.

Inhibition of Human Platelet Aggregation and Low-Density Lipoprotein Oxidation by Premna foetida Extract and Its Major Compounds

Many Premna species have been used in traditional medicine to treat hypertension and cardiac insufficiency, and as a tonic for cardiac-related problems. Some have been reported to possess cardiovascular protective activity through several possible mechanisms, but not Premna foetida. In the present study, the methanol extract of P. foetida leaves (PFM) and its isolated compounds were evaluated for their ability to inhibit copper-mediated human low-density lipoprotein (LDL) oxidation and arachidonic acid (AA)- and adenosine diphosphate (ADP)-induced platelet aggregation. Six flavonoids, three triterpenoids, vanillic acid and stigmasterol were successfully isolated from PFM. Of the isolated compounds, quercetin was the most active against LDL oxidation (IC₅₀ 4.25 µM). The flavonols were more active than the flavones against LDL oxidation, suggesting that hydroxyl group at C-3 and the catechol moiety at B-ring may play important roles in protecting LDL from oxidation. Most tested flavonoids showed stronger inhibition towards AA-induced than the ADP-induced platelet aggregation with apigenin exhibiting the strongest effect (IC₅₀ 52.3 and 127.4 µM, respectively) while quercetin and kaempferol showed moderate activity. The results suggested that flavonoids, especially quercetin, apigenin and kaempferol were among the major constituents of P. foetida responsible for anti-LDL oxidation and anti-platelet aggregation.

New aporphine alkaloids from the aerial parts of Piper semiimmersum §

Two new aporphine alkaloids, semiimmersumines A (1) and B (2), along with 20 known compounds, were isolated from the aerial parts of Piper semiimmersum (Piperaceae). The structures of the new compounds were elucidated based on the analysis of 1D and 2D NMR, MS, and CD data. The absolute configuration of semiimmersumine A (1) was determined by single crystal X-ray diffraction analysis using anomalous dispersion with copper radiation. The effects of all compounds from the plant on rabbit platelet aggregation induced by thrombin (IIa) or PAF were also evaluated.

Differential proteomic analysis of platelets suggested target-related proteins in rabbit platelets treated with Rhizoma Corydalis

CONTEXT

Corydalis yanhusuo W.T. Wang (Papaveraceae) (Rhizoma Corydalis) showed inhibitory effects on rabbit platelet aggregation induced by ADP, thrombin (THR) or arachidonic acid (AA).

OBJECTIVE

This study separates and identifies the possible target-related platelet proteins and suggests possible signal cascades of RC antiplatelet aggregation.

MATERIALS AND METHODS

Based on comparative proteomics, the differentially expressed platelet proteins treated before and after with 50 mg/mL RC 90% ethanol extract (for 15 min at 37 °C) were analyzed and identified by two dimensional gel electrophoresis (2-DE) and MALDI-TOF-MS/MS. To further verify the possible signalling pathways of RC antiplatelet aggregation function, the concentration of calcium (Ca²⁺) was measured by Fura-2/AM fluorescence (Ex 340/380 nm, Em 500 nm) (RC final concentrations of 0.0156-0.1563 mg/mL), the levels of P-selectin and cyclic guanosine monophosphate (cGMP) were quantified by ELISA (OD. 450 nm) (RC final concentrations of 0.0156-1.5625 mg/mL), and the 5-hydroxytryptamine (5-HT) level was measured using ortho-phthalaldehyde (OPT) fluorescence (Ex 340 nm, Em 470 nm) (RC final concentrations of 0.3125-1.5625 mg/mL).

RESULTS

The expression of 52 proteins were altered in rabbit platelets after the treatment and the MALDI-TOF-MS analysis indicated that those proteins include 12 cytoskeleton proteins, 7 cell signalling proteins, 3 molecular chaperone proteins, 6 proteins related to platelet function, 16 enzymes and 7 other related proteins. Furthermore, RC extract could decrease the levels of 5-HT [inhibition rate of 96.80% (p < 0.05, vs. THR-activated group) treated with 0.7813 mg/mL of RC], Ca²⁺[172.73 ± 5.07 to 113.56 ± 5.46 nM (p < 0.001, vs. THR-activated group) treated with 0.0313 mg/mL of RC] and P-selectin [13.48 ± 0.96 ng/3 × 10⁸ to 11.64 ± 0.17 ng/3 × 10⁸ (p < 0.05, vs. THR-activated group) treated with 0.0156 mg/mL of RC], and increase in cGMP level [38.93 ± 0.57 to 50.26 ± 4.05 ng/3 × 10⁸ (p < 0.05, vs. THR-activated group) treated with 1.5165 mg/mL of RC] in ADP (10 μmol/L), THR (0.25 u/mL) or AA-(0.205 mmol/L) activated rabbit platelets.

DISCUSSION AND CONCLUSION

The present study indicated that P2Y12 receptor might be one of the direct target proteins of RC in platelets. The signal cascades network of RC after binding with P2Y12 receptor is mediating Gαi proteins to activate downstream signalling pathways (AC and/or PI3K signalling pathways) for the inhibition of platelet aggregation.

Design, Synthesis and Pharmacological Evaluation of Novel Piperlongumine derivatives as Potential Antiplatelet Aggregation Candidate

A series of novel piperlongumine derivatives (4a-i, 6a-i) were designed and synthesized. The inhibitory activities of platelet aggregation induced by ADP and AA in vitro have been evaluated by bron turbidimetry and liver microsomal incubated assay. The assay results show that compounds 4e and 6e exhibited remarkable potency to that of the positive control piplartine and aspirin.

Multiobjective optimization on antiplatelet effects of three components combination by quantitative composition-activity relationship modeling and weighted-sum method

Multicomponent therapeutic has become an increasingly favored strategy for treating complex diseases in recent years. In this study, a multiple objective optimization approach was proposed to design the optimal combination of three components for antiplatelet activity. The platelet aggregation assays induced by three different ways, adenosine diphosphate, arachidonic acid, and collagen, were applied to evaluate the in vitro antiplatelet activities of three active components derived from a traditional Chinese medicine. After analyzing this dataset by quantitative composition-activity relationship modeling, a weighted-sum optimization method was adopted to calculate the optimal ratio between three components for antiplatelet effects. Further experiments validated our method and showed that better antiplatelet activity was exerted by the optimized combination than the individual component or other combinations. Our findings suggested that the proposed multiobjective optimization approach is a novel method for multicomponent drug design.