Data on hyper-activation of GPVI signalling in obese patients: Towards the identification of novel antiplatelet targets in obesity.
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SUBMITTER: Barrachina MN
PROVIDER: S-EPMC6661234 | biostudies-literature | 2019 Apr
REPOSITORIES: biostudies-literature
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Data on hyper-activation of GPVI signalling in obese patients: Towards the identification of novel antiplatelet targets in obesity.
Barrachina María N MN Izquierdo Irene I Hermida-Nogueira Lidia L Sueiro Aurelio M AM Guitián Esteban E Casanueva Felipe F FF Farndale Richard W RW Moroi Masaaki M Jung Stephanie M SM Pardo María M García Ángel Á
Data in brief 20190228
This data article is associated with the manuscript "GPVI surface expression and signalling pathway activation are increased in platelets from obese patients: elucidating potential anti-atherothrombotic targets in obesity" [1]. The study refers to a combination of different approaches in order to identify platelet-derived biomarkers in obesity. A total of 34 obese patients and their lean-matched controls were included in the study. We carried out a proteomic and functional (aggregation assays) a ...[more]
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Project description:BackgroundDue to mTOR (mammalian/mechanistic target of rapamycin) gene-loss mice die during embryonic development, the role of mTOR in platelets has not been evaluated using gene knockout technology.MethodsA mouse model with megakaryocyte/platelet-specific deletion of mTOR was established, and be used to evaluate the role of mTOR in platelet activation and thrombus formation.ResultsmTOR-/- platelets were deficient in thrombus formation when grown on low-concentration collagen-coated surfaces; however, no deficiency in thrombus formation was observed when mTOR-/- platelets were perfused on higher concentration collagen-coated surfaces. In FeCl3-induced mouse mesenteric arteriole thrombosis models, wild-type (WT) and mTOR-/- mice displayed significantly different responses to low-extent injury with respect to the ratio of occluded mice, especially within the first 40 min. Additionally, mTOR-/- platelets displayed reduced aggregation and dense granule secretion (ATP release) in response to low doses of the glycoprotein VI (GPVI) agonist collagen related peptide (CRP) and the protease-activated receptor-4 (PAR4) agonist GYPGKF-NH2; these deficiencies were overcame by stimulation with higher concentration agonists, suggesting dose dependence of the response. At low doses of GPVI or PAR agonist, the activation of αIIbβ3 in mTOR-/- platelets was reduced. Moreover, stimulation of mTOR-/- platelets with low-dose CRP attenuated the phosphorylation of S6K1, S6 and Akt Ser473, and increased the phosphorylation of PKCδ Thr505 and PKCε Ser729. Using isoform-specific inhibitors of PKCs (δ, ɛ, and α/β), we established that PKCδ/ɛ, and especially PKCδ but not PKCα/β or PKCθ, may be involved in low-dose GPVI-mediated/mTOR-dependent signaling.ConclusionThese observations indicate that mTOR plays an important role in GPVI-dependent platelet activation and thrombus formation.
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