Other search tools

About this data

The publication data currently available has been vetted by Vanderbilt faculty, staff, administrators and trainees. The data itself is retrieved directly from NCBI's PubMed and is automatically updated on a weekly basis to ensure accuracy and completeness.

If you have any questions or comments, please contact us.

Results: 1 to 10 of 228

Publication Record

Connections

Platelet-Based Drug Delivery for Cancer Applications.
Ortiz-Otero N, Mohamed Z, King MR
(2018) Adv Exp Med Biol 1092: 235-251
MeSH Terms: Blood Platelets, Drug Delivery Systems, Hemostasis, Humans, Male, Neoplasm Metastasis, Neoplasms
Show Abstract · Added April 15, 2019
Platelets can be considered as the "guardian of hemostasis" where their main function is to maintain vascular integrity. In pathological conditions, the hemostatic role of platelets may be hijacked to stimulate disease progression. In 1865, Armand Trousseau was a pioneer in establishing the platelet-cancer metastasis relationship, which he eventually termed as Trousseau's Syndrome to describe the deregulation of the hemostasis-associated pathways induced by cancer progression (Varki, Blood. 110(6):1723-9, 2007). Since these early studies, there has been an increase in experimental evidence not only to elucidate the role of platelets in cancer metastasis but also to create novel cancer therapies by targeting the platelet's impact in metastasis. In this chapter, we discuss the contribution of platelets in facilitating tumor cell transit from the primary tumor to distant metastatic sites as well as novel cancer therapies based on platelet interactions.
0 Communities
1 Members
0 Resources
7 MeSH Terms
Loss of Serotonin Transporter Function Alters ADP-mediated Glycoprotein αIIbβ3 Activation through Dysregulation of the 5-HT2A Receptor.
Oliver KH, Duvernay MT, Hamm HE, Carneiro AM
(2016) J Biol Chem 291: 20210-9
MeSH Terms: Adenosine Diphosphate, Animals, Blood Platelets, Citalopram, Female, Male, Mice, Mice, Knockout, Platelet Glycoprotein GPIIb-IIIa Complex, Receptor, Serotonin, 5-HT2A, Serotonin Plasma Membrane Transport Proteins
Show Abstract · Added October 26, 2016
Reduced platelet aggregation and a mild bleeding phenotype have been observed in patients chronically taking selective serotonin reuptake inhibitors (SSRIs). However, it remains unclear how SSRIs, which inhibit the plasma membrane serotonin transporter (SERT), modulate hemostasis. Here, we examine how sustained inhibition of SERT activity alters serotonergic signaling and influences platelet activation and hemostasis. Pharmaceutical blockade (citalopram dosing) or genetic ablation (SERT(-/-)) of SERT function in vivo led to reduced serotonin (5-hydroxytryptamine (5-HT)) blood levels that paralleled a mild bleeding phenotype in mice. Transfusion of wild-type platelets to SERT(-/-) mice normalized bleeding times to wild-type levels, suggesting that loss of SERTs causes a deficiency in platelet activation. Although SERT(-/-) platelets displayed no difference in P-selectin or αIIbβ3 activation upon stimulation with thrombin, ADP-mediated αIIbβ3 activation is reduced in SERT(-/-) platelets. Additionally, synergistic potentiation of αIIbβ3 activation by ADP and 5-HT is lost in SERT(-/-) platelets. Acute treatment of wild-type platelets with 5-HT2A receptor (5-HT2AR) antagonists or SSRIs revealed that functional 5-HT2ARs, not SERTs, are necessary for the synergistic activation of αIIbβ3 by dual 5-HT/ADP stimulation. Pharmacological studies using radiolabeled guanosine 5'-3-O-([(35)S]thio)triphosphate and [(3)H]ketanserin revealed that platelets isolated from SERT(-/-) or citalopram-treated mice have reduced activation of G-proteins coupled to 5-HT2ARs and receptor surface expression. Taken together, these data demonstrate that sustained SERT loss of function reduces 5-HT2AR surface expression that is critical for the synergistic activation of αIIbβ3 by 5-HT and ADP. These results highlight an antiplatelet strategy centered on blocking or desensitizing 5-HT2AR to attenuate ADP-mediated αIIbβ3 activation.
© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
1 Communities
2 Members
0 Resources
11 MeSH Terms
Platelet-Related Variants Identified by Exomechip Meta-analysis in 157,293 Individuals.
Eicher JD, Chami N, Kacprowski T, Nomura A, Chen MH, Yanek LR, Tajuddin SM, Schick UM, Slater AJ, Pankratz N, Polfus L, Schurmann C, Giri A, Brody JA, Lange LA, Manichaikul A, Hill WD, Pazoki R, Elliot P, Evangelou E, Tzoulaki I, Gao H, Vergnaud AC, Mathias RA, Becker DM, Becker LC, Burt A, Crosslin DR, Lyytikäinen LP, Nikus K, Hernesniemi J, Kähönen M, Raitoharju E, Mononen N, Raitakari OT, Lehtimäki T, Cushman M, Zakai NA, Nickerson DA, Raffield LM, Quarells R, Willer CJ, Peloso GM, Abecasis GR, Liu DJ, Global Lipids Genetics Consortium, Deloukas P, Samani NJ, Schunkert H, Erdmann J, CARDIoGRAM Exome Consortium, Myocardial Infarction Genetics Consortium, Fornage M, Richard M, Tardif JC, Rioux JD, Dube MP, de Denus S, Lu Y, Bottinger EP, Loos RJ, Smith AV, Harris TB, Launer LJ, Gudnason V, Velez Edwards DR, Torstenson ES, Liu Y, Tracy RP, Rotter JI, Rich SS, Highland HM, Boerwinkle E, Li J, Lange E, Wilson JG, Mihailov E, Mägi R, Hirschhorn J, Metspalu A, Esko T, Vacchi-Suzzi C, Nalls MA, Zonderman AB, Evans MK, Engström G, Orho-Melander M, Melander O, O'Donoghue ML, Waterworth DM, Wallentin L, White HD, Floyd JS, Bartz TM, Rice KM, Psaty BM, Starr JM, Liewald DC, Hayward C, Deary IJ, Greinacher A, Völker U, Thiele T, Völzke H, van Rooij FJ, Uitterlinden AG, Franco OH, Dehghan A, Edwards TL, Ganesh SK, Kathiresan S, Faraday N, Auer PL, Reiner AP, Lettre G, Johnson AD
(2016) Am J Hum Genet 99: 40-55
MeSH Terms: Blood Platelets, Exome, Female, Genetic Variation, Genome-Wide Association Study, Humans, Male, Mean Platelet Volume, Platelet Count
Show Abstract · Added April 26, 2017
Platelet production, maintenance, and clearance are tightly controlled processes indicative of platelets' important roles in hemostasis and thrombosis. Platelets are common targets for primary and secondary prevention of several conditions. They are monitored clinically by complete blood counts, specifically with measurements of platelet count (PLT) and mean platelet volume (MPV). Identifying genetic effects on PLT and MPV can provide mechanistic insights into platelet biology and their role in disease. Therefore, we formed the Blood Cell Consortium (BCX) to perform a large-scale meta-analysis of Exomechip association results for PLT and MPV in 157,293 and 57,617 individuals, respectively. Using the low-frequency/rare coding variant-enriched Exomechip genotyping array, we sought to identify genetic variants associated with PLT and MPV. In addition to confirming 47 known PLT and 20 known MPV associations, we identified 32 PLT and 18 MPV associations not previously observed in the literature across the allele frequency spectrum, including rare large effect (FCER1A), low-frequency (IQGAP2, MAP1A, LY75), and common (ZMIZ2, SMG6, PEAR1, ARFGAP3/PACSIN2) variants. Several variants associated with PLT/MPV (PEAR1, MRVI1, PTGES3) were also associated with platelet reactivity. In concurrent BCX analyses, there was overlap of platelet-associated variants with red (MAP1A, TMPRSS6, ZMIZ2) and white (PEAR1, ZMIZ2, LY75) blood cell traits, suggesting common regulatory pathways with shared genetic architecture among these hematopoietic lineages. Our large-scale Exomechip analyses identified previously undocumented associations with platelet traits and further indicate that several complex quantitative hematological, lipid, and cardiovascular traits share genetic factors.
Published by Elsevier Inc.
0 Communities
1 Members
0 Resources
9 MeSH Terms
Activated tumor cell integrin αvβ3 cooperates with platelets to promote extravasation and metastasis from the blood stream.
Weber MR, Zuka M, Lorger M, Tschan M, Torbett BE, Zijlstra A, Quigley JP, Staflin K, Eliceiri BP, Krueger JS, Marchese P, Ruggeri ZM, Felding BH
(2016) Thromb Res 140 Suppl 1: S27-36
MeSH Terms: Animals, Blood Platelets, Cell Line, Tumor, Cell Movement, Humans, Integrin alphaVbeta3, Mice, SCID, Neoplasm Metastasis, Neoplastic Cells, Circulating
Show Abstract · Added April 6, 2017
Metastasis is the main cause of death in cancer patients, and understanding mechanisms that control tumor cell dissemination may lead to improved therapy. Tumor cell adhesion receptors contribute to cancer spreading. We noted earlier that tumor cells can expressing the adhesion receptor integrin αvβ3 in distinct states of activation, and found that cells which metastasize from the blood stream express it in a constitutively high affinity form. Here, we analyzed steps of the metastatic cascade in vivo and asked, when and how the affinity state of integrin αvβ3 confers a critical advantage to cancer spreading. Following tumor cells by real time PCR, non-invasive bioluminescence imaging, intravital microscopy and histology allowed us to identify tumor cell extravasation from the blood stream as a rate-limiting step supported by high affinity αvβ3. Successful transendothelial migration depended on cooperation between tumor cells and platelets involving the high affinity tumor cell integrin and release of platelet granules. Thus, this study identifies the high affinity conformer of integrin αvβ3 and its interaction with platelets as critical for early steps during hematogenous metastasis and target for prevention of metastatic disease.
© 2016 Elsevier Ltd. All rights reserved.
1 Communities
1 Members
0 Resources
9 MeSH Terms
Structural Basis for Sialoglycan Binding by the Streptococcus sanguinis SrpA Adhesin.
Bensing BA, Loukachevitch LV, McCulloch KM, Yu H, Vann KR, Wawrzak Z, Anderson S, Chen X, Sullam PM, Iverson TM
(2016) J Biol Chem 291: 7230-40
MeSH Terms: Adhesins, Bacterial, Binding Sites, Blood Platelets, Endocarditis, Humans, N-Acetylneuraminic Acid, Streptococcal Infections, Streptococcus, Virulence Factors
Show Abstract · Added April 1, 2019
Streptococcus sanguinisis a leading cause of infective endocarditis, a life-threatening infection of the cardiovascular system. An important interaction in the pathogenesis of infective endocarditis is attachment of the organisms to host platelets.S. sanguinisexpresses a serine-rich repeat adhesin, SrpA, similar in sequence to platelet-binding adhesins associated with increased virulence in this disease. In this study, we determined the first crystal structure of the putative binding region of SrpA (SrpABR) both unliganded and in complex with a synthetic disaccharide ligand at 1.8 and 2.0 Å resolution, respectively. We identified a conserved Thr-Arg motif that orients the sialic acid moiety and is required for binding to platelet monolayers. Furthermore, we propose that sequence insertions in closely related family members contribute to the modulation of structural and functional properties, including the quaternary structure, the tertiary structure, and the ligand-binding site.
© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
0 Communities
1 Members
0 Resources
MeSH Terms
Platelet response to increased aspirin dose in patients with persistent platelet aggregation while treated with aspirin 81 mg.
Gengo F, Westphal ES, Rainka MM, Janda M, Robson MJ, Hourihane JM, Bates V
(2016) J Clin Pharmacol 56: 414-21
MeSH Terms: Aspirin, Blood Coagulation Tests, Blood Platelets, Collagen, Drug Resistance, Female, Humans, Male, Middle Aged, Platelet Aggregation, Platelet Aggregation Inhibitors, Platelet Function Tests
Show Abstract · Added August 26, 2015
This study demonstrates that patients who are taking 81 mg of aspirin and are nonresponsive benefit from a dose of 162 mg or greater vs a different antiplatelet therapy. We identified 100 patients who were nonresponsive to aspirin 81 mg via whole blood aggregometry and observed how many patients became responsive at a dose of 162 mg or greater. Platelet nonresponsiveness was defined as >10 Ω of resistance to collagen 1 µg/mL and/or an ohms ratio of collagen 1 µg/mL to collagen 5 µg/mL >0.5 and/or >6 Ω to arachidonate. Borderline response was defined as an improvement in 1 but not both of the above criteria. Of the initial 100 patients who were nonresponsive to an aspirin dose of 81 mg, 79% became responsive at a dose of 162 mg or >162 mg. Only 6% did not respond to any increase in dose. We believe that patients treated with low-dose aspirin who have significant risk for secondary vascular events should be individually assessed to determine their antiplatelet response. Those found to have persistent platelet aggregation despite treatment with 81 mg of aspirin have a higher likelihood of obtaining an adequate antiplatelet response at a higher aspirin dose.
© 2015, The American College of Clinical Pharmacology.
0 Communities
1 Members
0 Resources
12 MeSH Terms
Inherited human group IVA cytosolic phospholipase A2 deficiency abolishes platelet, endothelial, and leucocyte eicosanoid generation.
Kirkby NS, Reed DM, Edin ML, Rauzi F, Mataragka S, Vojnovic I, Bishop-Bailey D, Milne GL, Longhurst H, Zeldin DC, Mitchell JA, Warner TD
(2015) FASEB J 29: 4568-78
MeSH Terms: Adult, Antigens, Human Platelet, Blood Platelets, Dinoprostone, Endothelial Cells, Epoprostenol, Female, Humans, Leukocytes, Male, Mutation, Platelet Activation
Show Abstract · Added March 10, 2016
Eicosanoids are important vascular regulators, but the phospholipase A2 (PLA2) isoforms supporting their production within the cardiovascular system are not fully understood. To address this, we have studied platelets, endothelial cells, and leukocytes from 2 siblings with a homozygous loss-of-function mutation in group IVA cytosolic phospholipase A2 (cPLA2α). Chromatography/mass spectrometry was used to determine levels of a broad range of eicosanoids produced by isolated vascular cells, and in plasma and urine. Eicosanoid release data were paired with studies of cellular function. Absence of cPLA2α almost abolished eicosanoid synthesis in platelets (e.g., thromboxane A2, control 20.5 ± 1.4 ng/ml vs. patient 0.1 ng/ml) and leukocytes [e.g., prostaglandin E2 (PGE2), control 21.9 ± 7.4 ng/ml vs. patient 1.9 ng/ml], and this was associated with impaired platelet activation and enhanced inflammatory responses. cPLA2α-deficient endothelial cells showed reduced, but not absent, formation of prostaglandin I2 (prostacyclin; control 956 ± 422 pg/ml vs. patient 196 pg/ml) and were primed for inflammation. In the urine, prostaglandin metabolites were selectively influenced by cPLA2α deficiency. For example, prostacyclin metabolites were strongly reduced (18.4% of control) in patients lacking cPLA2α, whereas PGE2 metabolites (77.8% of control) were similar to healthy volunteer levels. These studies constitute a definitive account, demonstrating the fundamental role of cPLA2α to eicosanoid formation and cellular responses within the human circulation.
© FASEB.
1 Communities
0 Members
0 Resources
12 MeSH Terms
Pharmacokinetic, partial pharmacodynamic and initial safety analysis of (-)-epicatechin in healthy volunteers.
Barnett CF, Moreno-Ulloa A, Shiva S, Ramirez-Sanchez I, Taub PR, Su Y, Ceballos G, Dugar S, Schreiner G, Villarreal F
(2015) Food Funct 6: 824-33
MeSH Terms: Adult, Aged, Anti-Inflammatory Agents, Non-Steroidal, Biomarkers, Blood Platelets, Cardiovascular Diseases, Catechin, Citrate (si)-Synthase, Dietary Supplements, Electron Transport Chain Complex Proteins, Female, Follistatin, Humans, Intestinal Absorption, Kinetics, Male, Middle Aged, Nitric Oxide, Toxicity Tests, Subchronic, Young Adult
Show Abstract · Added January 20, 2015
(-)-Epicatechin ((-)-EPI), a naturally occurring flavanol, has emerged as a likely candidate for cocoa-based product reported reductions in cardiometabolic risk. The present study aimed to determine the safety, tolerability, pharmacokinetics and pharmacodynamics of purified (-)-EPI administered to healthy volunteers. In this phase I, open-label, two-part single- and multiple-dose study, subjects received either a single dose (n = 9) of 50, 100 or 200 mg or multiple doses (n = 8) of 50 mg daily (q.d.) or twice daily (b.i.d) for 5 days. Blood was collected at 0, 0.5, 1, 2, 4 and 6 h after (-)-EPI administration in the single and multiple dose groups (blood collection repeated in day 5). Samples were analyzed by HPLC-HR-ESI-MS for EPI and metabolite quantification. In the q.d. and b.i.d. groups, blood samples were analyzed for NO surrogates and follistatin levels as well as, platelet mitochondrial complexes I, V and citrate synthase activity levels. (-)-EPI was well tolerated and readily absorbed with further phase 2 metabolism. On day 5, in the q.d. and b.i.d. groups, there were significant increases in plasma nitrite of 30% and 17%, respectively. In the q.d. group on day 5 vs. day 1, platelet mitochondrial complexes I, IV and citrate synthase activities demonstrated a significant increase of ∼92, 62 and 8%, respectively. Average day 5 follistatin AUC levels were ∼2.5 fold higher vs. day 1 AUC levels in the b.i.d. group. (-)-EPI was safe to use, with no observed adverse effects, and our findings suggest that increases in NO metabolites, mitochondrial enzyme function and plasma follistatin levels may underlie some of the beneficial effects of cocoa products or (-)-EPI as reported in other studies.
0 Communities
1 Members
0 Resources
20 MeSH Terms
Inflammatory cytokine TSLP stimulates platelet secretion and potentiates platelet aggregation via a TSLPR-dependent PI3K/Akt signaling pathway.
Dong J, Dong J, Lin J, Wang B, He S, Wu C, Kushwaha KK, Mohabeer N, Su Y, Fang H, Huang K, Li D
(2015) Cell Physiol Biochem 35: 160-74
MeSH Terms: Androstadienes, Animals, Blood Platelets, Carotid Artery Thrombosis, Chlorides, Chromones, Cytokines, Disease Models, Animal, Ferric Compounds, Humans, Immunoglobulins, Mice, Mice, Inbred C57BL, Mice, Knockout, Morpholines, P-Selectin, Phosphatidylinositol 3-Kinases, Phosphorylation, Platelet Activation, Platelet Aggregation, Platelet Glycoprotein GPIIb-IIIa Complex, Proto-Oncogene Proteins c-akt, Receptors, Cytokine, Signal Transduction, Wortmannin
Show Abstract · Added January 20, 2015
AIMS - Thymic stromal lymphopoietin (TSLP) plays an important role in inflammatory diseases and is over-expressed in human atherosclerotic artery specimens. The present study investigated the role of TSLP in platelet activation and thrombosis models in vitro and in vivo, as well as the underlying mechanism and signaling pathway.
METHODS AND RESULTS - Western blotting and flow cytometry demonstrated that the TSLP receptor was expressed on murine platelets. According to flow cytometry, platelet stimulation with TSLP induced platelet degranulation and integrin αIIbβ3 activation. A TSLPR deficiency caused defective platelet aggregation, defective platelet secretion and markedly blunted thrombus growth in perfusion chambers at both low and high shear rates. TSLPR KO mice exhibited defective carotid artery thrombus formation after exposure to FeCl3. TSLP increased Akt phosphorylation, an effect that was abrogated by the PI3K inhibitors wortmannin and LY294002. The PI3K inhibitors further diminished TSLP-induced platelet activation. TSLP-mediated platelet degranulation, integrin αIIbβ3 activation and Akt phosphorylation were blunted in platelets that lacked the TSLP receptor.
CONCLUSION - This study demonstrated that the functional TSLPR was surface-expressed on murine platelets. The inflammatory cytokine TSLP triggered platelet activation and thrombus formation via TSLP-dependent PI3K/Akt signaling, which suggests an important role for TSLP in linking vascular inflammation and thrombo-occlusive diseases.
© 2015 S. Karger AG, Basel.
0 Communities
1 Members
0 Resources
25 MeSH Terms
Activated factor XI increases the procoagulant activity of the extrinsic pathway by inactivating tissue factor pathway inhibitor.
Puy C, Tucker EI, Matafonov A, Cheng Q, Zientek KD, Gailani D, Gruber A, McCarty OJ
(2015) Blood 125: 1488-96
MeSH Terms: Blood Coagulation, Blood Platelets, Blotting, Western, Cells, Cultured, Factor IX, Factor XIa, Factor Xa, Fibrin, Flow Cytometry, Human Umbilical Vein Endothelial Cells, Humans, Lipoproteins, Mutation, Recombinant Proteins
Show Abstract · Added January 20, 2015
Activation of coagulation factor XI (FXI) may play a role in hemostasis. The primary substrate of activated FXI (FXIa) is FIX, leading to FX activation (FXa) and thrombin generation. However, recent studies suggest the hemostatic role of FXI may not be restricted to the activation of FIX. We explored whether FXI could interact with and inhibit the activity of tissue factor pathway inhibitor (TFPI). TFPI is an essential reversible inhibitor of activated factor X (FXa) and also inhibits the FVIIa-TF complex. We found that FXIa neutralized both endothelium- and platelet-derived TFPI by cleaving the protein between the Kunitz (K) 1 and K2 domains (Lys86/Thr87) and at the active sites of the K2 (Arg107/Gly108) and K3 (Arg199/Ala200) domains. Addition of FXIa to plasma was able to reverse the ability of TFPI to prolong TF-initiated clotting times in FXI- or FIX-deficient plasma, as well as FXa-initiated clotting times in FX-deficient plasma. Treatment of cultured endothelial cells with FXIa increased the generation of FXa and promoted TF-dependent fibrin formation in recalcified plasma. Together, these results suggest that the hemostatic role of FXIa may be attributed not only to activation of FIX but also to promoting the extrinsic pathway of thrombin generation through inactivation of TFPI.
© 2015 by The American Society of Hematology.
0 Communities
1 Members
0 Resources
14 MeSH Terms