Objective To evaluate whether Vibrio vulnificus secreted exotoxin-hemolysin (VVH) can activate platelet, an important blood immune cell, and to explore the possible molecular mechanism of platelet activation by VVH. Methods Transcriptomics and immunohistochemistry were used to analyze whether Vibrio vulnificus infection caused platelet activation in mice. Then, flow cytometry was used to identify whether VVH was the main stimulator of platelet activation. Naturally expressed VVH toxin was purified and prepared. The effects of extracellular and intracellular Ca²⁺ signal inhibitors on VVH activated platelets were evaluated by flow cytometry and Western blotting. The immune activation effect of VVH in the early stage of Vibrio vulnificus infection was analyzed in vivo. Results VVH was the main stimulator of platelet activation in Vibrio vulnificus culture supernatant. Natural VVH can induce the increase of P-selectin (CD62P) on platelet surface, the formation of platelet-neutrophil complex (PNC), and the release of platelet microvesicles. The activation mechanism may be related to the VVH pore-dependent Ca²⁺-calmodulin (CaM) -myosin light chain kinase (MLCK) signaling pathway, which led to the release of platelet alpha particles and cascade activation of platelets. In a mouse model of ALD infected by Vibrio vulnificus gavage, VVH was strongly associated with platelet activation. Conclusion This study shows that VVH is an important platelet activating molecule in the early stage of Vibrio vulnificus infection, and its induction of platelet activation may be related to the pathogenic process.
Animals ; Platelet Activation/drug effects* ; Hemolysin Proteins/pharmacology* ; Vibrio vulnificus/metabolism* ; Mice ; Blood Platelets/drug effects* ; Vibrio Infections/immunology* ; P-Selectin/metabolism* ; Bacterial Proteins ; Female

OBJECTIVE: To investigate the effects of oridonin on platelet function and related mechanisms. METHODS: Washed platelets from healthy adults and mice were incubated with different concentrations of oridonin (2.5, 5 and 10 μmol/L) in vitro . The surface expression level of P-selectin and the activation of integrin αIIbβ3 in platelets were detected by flow cytometry, and the aggregation ability of platelets under the stimulation by various agonists was detected by light transmission aggregometry. The expression of P-AKT (Ser473) was detected by protein immunoblotting. Arterial thrombosis model was established in mice with mesenteric injury induced by ferric chloride, and tail hemorrhage model was established by cutting off the tail of mice. The effect of intraperitoneal injection of oridonin (10 mg/kg) on thrombosis and haemostasis was tested. RESULTS: Oridonin inhibited platelet P-selectin expression and integrin αIIbβ3 activation. In the presence of different stimulants, oridonin inhibited platelet aggregation in a concentration-dependent manner. The phosphorylation level of AKT Ser473 was reduced in the groups treated with different concentrations of oridonin. Oridonin significantly prolonged the time of mesenteric artery thrombosis in mice, but did not affect the tail bleeding time. CONCLUSION Oridonin inhibits platelet activation, aggregation, and thrombosis by inhibiting AKT phosphorylation, and may be used as a potential antiplatelet drug.
Diterpenes, Kaurane/pharmacology* ; Animals ; Mice ; Blood Platelets/drug effects* ; Platelet Aggregation/drug effects* ; P-Selectin/metabolism* ; Thrombosis ; Platelet Glycoprotein GPIIb-IIIa Complex/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Humans ; Phosphorylation ; Platelet Activation/drug effects*

OBJECTIVE: To investigate the effect of zedoarondiol on neovascularization of atherosclerotic (AS) plaque by exosomes experiment. METHODS: ApoE^-/- mice were fed with high-fat diet to establish AS model and treated with high- and low-dose (10, 5 mg/kg daily) of zedoarondiol, respectively. After 14 weeks, the expressions of anti-angiogenic protein thrombospondin 1 (THBS-1) and its receptor CD36 in plaques, as well as platelet activation rate and exosome-derived miR-let-7a were detected. Then, zedoarondiol was used to intervene in platelets in vitro, and miR-let-7a was detected in platelet-derived exosomes (Pexo). Finally, human umbilical vein endothelial cells (HUVECs) were transfected with miR-let-7a mimics and treated with Pexo to observe the effect of miR-let-7a in Pexo on tube formation. RESULTS: Animal experiments showed that after treating with zedoarondiol, the neovascularization density in plaques of AS mice was significantly reduced, THBS-1 and CD36 increased, the platelet activation rate was markedly reduced, and the miR-let-7a level in Pexo was reduced (P<0.01). In vitro experiments, the platelet activation rate and miR-let-7a levels in Pexo were significantly reduced after zedoarondiol's intervention. Cell experiments showed that after Pexo's intervention, the tube length increased, and the transfection of miR-let-7a minics further increased the tube length of cells, while reducing the expressions of THBS-1 and CD36. CONCLUSION Zedoarondiol has the effect of inhibiting neovascularization within plaque in AS mice, and its mechanism may be potentially related to inhibiting platelet activation and reducing the Pexo-derived miRNA-let-7a level.
Animals ; MicroRNAs/genetics* ; Exosomes/drug effects* ; Plaque, Atherosclerotic/genetics* ; Neovascularization, Pathologic/genetics* ; Human Umbilical Vein Endothelial Cells/metabolism* ; Humans ; Blood Platelets/drug effects* ; Apolipoproteins E/deficiency* ; Thrombospondin 1/metabolism* ; CD36 Antigens/metabolism* ; Platelet Activation/drug effects* ; Male ; Mice ; Mice, Inbred C57BL

Hypoxemia is a common pathological state characterized by low oxygen saturation in the blood. This condition compromises mucosal barrier integrity particularly in the gut and oral cavity. However, the mechanisms underlying this association remain unclear. This study used periodontitis as a model to investigate the role of platelet activation in oral mucosal immunopathology under hypoxic conditions. Hypoxia upregulated methyltransferase-like protein 4 (METTL4) expression in platelets, resulting in N⁶-methyladenine modification of mitochondrial DNA (mtDNA). This modification impaired mitochondrial transcriptional factor A-dependent cytosolic mtDNA degradation, leading to cytosolic mtDNA accumulation. Excess cytosolic mt-DNA aberrantly activated the cGAS-STING pathway in platelets. This resulted in excessive platelet activation and neutrophil extracellular trap formation that ultimately exacerbated periodontitis. Targeting platelet METTL4 and its downstream pathways offers a potential strategy for managing oral mucosa immunopathology. Further research is needed to examine its broader implications for mucosal inflammation under hypoxic conditions.
DNA, Mitochondrial/metabolism* ; Mouth Mucosa/pathology* ; Hypoxia/immunology* ; Methyltransferases/metabolism* ; Blood Platelets/metabolism* ; Animals ; Periodontitis/immunology* ; Humans ; Platelet Activation ; Mice

OBJECTIVE: To study the effect of gradient shear stress on platelet aggregation by microfluidic chip Technology. METHODS: Microfluidic chip was used to simulate 80% fixed stenotic microchannel, and the hydrodynamic behavior of the stenotic microchannel model was analyzed by the finite element analysis module of sollidwork software. Microfluidic chip was used to analyze the adhesion and aggregation behavior of platelets in patients with different diseases, and flow cytometry was used to detect expression of the platelet activation marker CD62p. Aspirin, Tirofiban and protocatechuic acid were used to treat the blood, and the adhesion and aggregation of platelets were observed by fluorescence microscope. RESULTS: The gradient fluid shear rate produced by the stenosis model of microfluidic chip could induce platelet aggregation, and the degree of platelet adhesion and aggregation increased with the increase of shear rate within a certain range of shear rate. The effect of platelet aggregation in patients with arterial thrombotic diseases were significantly higher than normal group (P<0.05), and the effect of platelet aggregation in patients with myelodysplastic disease was lower than normal group (P<0.05). CONCLUSION The microfluidic chip analysis technology can accurately analyze and evaluate the platelet adhesion and aggregation effects of various thrombotic diseases unde the environment of the shear rate, and is helpful for auxiliary diagnosis of clinical thrombotic diseases.
Humans ; Microfluidics ; Platelet Adhesiveness ; Platelet Aggregation ; Blood Platelets/metabolism* ; Platelet Aggregation Inhibitors/pharmacology* ; Platelet Activation/physiology* ; Thrombosis

OBJECTIVE: To explore the regulation of mitochondria on platelet apoptosis and activation, and the relationship between platelet apoptosis and activation. METHODS: Platelets were isolated from peripheral venous blood of healthy volunteers. Cyclosporin A (CsA), which has a protective effect on the function of platelet mitochondria, BAPTA, which can chelate calcium ions across membranes in platelets, and NAC, an antioxidant that reduces the level of intracellular reactive oxygen species, were selected for coincubation with washed platelets, respectively. By flow cytometry, platelet aggregator was used to detect the changes of platelet mitochondrial function and platelet activation indexes after different interventions. RESULTS: H89, staurosporine, and A23187 led to platelet mitochondrial abnormalities, while CsA could effectively reverse the decline of platelet mitochondrial membrane potential caused by them. Antioxidant NAC could reverse platelet mitochondrial damage correspondingly, and completely reverse platelet shrinkage and phosphatidylserine eversion induced by H89. BAPTA, prostaglandin E1, acetylsalicylic acid and other inhibitors could not reverse the decline of platelet mitochondrial membrane potential. CONCLUSION Mitochondrial function plays an important role in platelet apoptosis and activation. Abnormal mitochondrial function causes the imbalance of reduction/oxidation state in platelets, which leads to platelet apoptosis. Platelet apoptosis and activation are independent signal processes.
Humans ; Blood Platelets/metabolism* ; Antioxidants/pharmacology* ; Mitochondria/physiology* ; Platelet Activation ; Apoptosis ; Membrane Potential, Mitochondrial ; Reactive Oxygen Species/pharmacology*

OBJECTIVE: To analysis the specific protein markers of essential thrombocythemia (ET) based on proteomics technology, to explore and verify the differential protein related to platelet activation. METHODS: Blood samples were obtained from ET patients and healthy people and a certain protein mass spectrometry was detected using label-free quantitative technology. The proteins relative abundance increased or down-regulated by 1.3 times in the disease group compared with the control group, and the protein abundance in the two groups t test P＜0.05 were defined as differential proteins. Bioinformatics analysis of the differential proteins was performed using GO and KEGG. The difference in the average protein abundance between the two groups was analyzed by t test and P＜0.05 was considered statistically significant. Differential proteins were selected for verification by parallel reaction monitoring (PRM) technology. RESULTS: A total of 140 differential proteins were found, of which 72 were up-regulated and 68 were down-regulated. KEGG enrichment showed that the differential protein expression was related to the platelet activation pathway. The differential proteins related to platelet activation were GPV, COL1A2, GP1bα, COL1A1 and GPVI. Among them, the expressions of GPV, GP1bα and GPVI were up-regulated, and the expressions of COL1A2 and COL1A1 were down-regulated. PRM verification of COL1A1, GP1bα, GPVI and GPV was consistent with LFP proteomics testing. CONCLUSION Differential proteins in ET patients are related to platelet activation pathway activation.Differential proteins such as GPV, GPVI, COL1A1 and GP1bα can be used as new targets related to ET platelet activation.
Blood Platelets/metabolism* ; Humans ; Platelet Activation ; Platelet Membrane Glycoproteins/metabolism* ; Technology ; Thrombocythemia, Essential

The abnormality of platelet function plays an important role in the pathogenesis and evolution of blood stasis syndrome (BSS). The explanation of its mechanism is a key scientific issue in the study of cardiovascular and cerebrovascular diseases and treatment. System biology technology provides a good technical platform for further development of platelet multi-omics, which is conducive to the scientific interpretation of the biological mechanism of BSS. The article summarized the pathogenesis of platelets in BSS, the mechanism of action of blood activating and stasis resolving drugs, and the application of genomics, proteomics, and metabonomics in platelet research, and put forward the concept of "plateletomics in BSS". Through the combination and cross-validation of multi-omics technology, it mainly focuses on the clinical and basic research of cardiovascular and cerebrovascular diseases; through the interactive verification of multi-omics technology and system biology, it mainly focuses on the platelet function and secretion system. The article systematically explains the molecular biological mechanism of platelet activation, aggregation, release, and other stages in the formation and development of BSS, and provides a new research idea and method for clarifying the pathogenesis of BSS and the mechanism of action of blood activating and stasis resolving drugs.
Blood Platelets ; Hemostasis ; Platelet Activation ; Proteomics ; Technology

OBJECTIVE: To investigate the effect of vitamin D3 to platelet activation by tumor cell culture medium. METHODS: The peripheral blood platelets of BALB/c mice were isolated. The platelets were activated in 4T1 culture fluid for 24 h. The platelets were divided into 7 groups: control group, activation group, 1 nmol/L vitamin D3 group, 10 nmol/L vitamin D3 group, 50 nmol/L vitamin D3 group, 100 nmol/L vitamin D3 group, and positive drug (0.1 μmol/L eptifibatide) group. CCK-8 assay was used to detect the platelet proliferation at 24, 48 and 72 h. Flow cytometry was used to detect the expression of CD61 and CD62p and receptor for advanced glycation end products (RAGE) at 24, 48 and 72 h. ELISA was used to detect the level of platelet-endothelial cell adhesion molecule-1 (PECAM-1) at 24, 48 and 72 h. RESULTS: The CD41 CONCLUSION Vitamin D3 shows antiplatelet effect and can inhibit platelet proliferation and activation.
Animals ; Blood Platelets ; Cell Culture Techniques ; Cholecalciferol/pharmacology* ; Flow Cytometry ; Mice ; Mice, Inbred BALB C ; P-Selectin ; Platelet Activation

The traditional Chinese medicine(TCM) syndrome of blood stasis refers to blood stagnation in meridians and viscera, with the main symptoms of pain, mass, bleeding, purple tongue, and unsmooth pulse. Cardiovascular and cerebrovascular diseases are among the major chronic diseases seriously harming the health of the Chinese. Among the coronary heart disease and stroke patients, most demonstrate the blood stasis syndrome. Platelet is considered to be one of the necessary factors in thrombosis, which closely relates to the TCM syndrome of blood stasis and the occurrence of cardiovascular and cerebrovascular diseases. The clinical and laboratory research on platelet activation and aggregation has been paid more and more attention. Its purpose is to treat and prevent blood stasis syndrome. In this study, the authors analyzed the research on the dysfunctions of platelets in blood stasis syndrome, biological basis of TCM blood stasis syndrome, and the effect of blood-activating stasis-resolving prescriptions on platelets, aiming at providing a reference for exploring the mechanism of platelet intervention in the treatment of TCM blood stasis syndrome and the pathways and targets of Chinese medicine in the prevention and treatment of the syndrome.
Blood Platelets ; Coronary Disease ; Humans ; Medicine, Chinese Traditional ; Platelet Activation ; Syndrome