Abstract
Microparticles play a role in cardiovascular disease pathology. The flavanol-like epicatechin is increasingly considered due to its cardioprotective effects. The aim of this study was to investigate the impact of epicatechin on microparticle generation, phenotype and procoagulant properties. Plasma samples from 15 healthy subjects were incubated with increasing concentrations of epicatechin (1 to 100 μM). Then, the expression of glycoprotein IIb, phosphatidylserine (PS), glycoprotein Ib (GPIb) and P-selectin was assessed by flow cytometry analysis after (or not) platelet stimulation. Microparticle procoagulant activity was determined using ZymuphenTM MP and ZymuphenTM MP-TF for phospholipid and tissue factor content, and with thrombin generation (TG) assays for procoagulant function. Platelet microparticles that express GPIb (/µL) decreased from 20,743 ± 24,985 (vehicle) to 14,939 ± 14,333 (p = 0.6), 21,366 ± 16,949 (p = 0.9) and 15,425 ± 9953 (p < 0.05) in samples incubated with 1, 10 and 100 µM epicatechin, respectively. Microparticle concentration (nM PS) decreased from 5.6 ± 2.0 (vehicle) to 5.1 ± 2.2 (p = 0.5), 4.5 ± 1.5 (p < 0.05) and 4.7 ± 2.0 (p < 0.05) in samples incubated with 1, 10 and 100µM epicatechin, respectively. Epicatechin had no impact on tissue factor-positive microparticle concentration. Epicatechin decreased TG (endogenous thrombin potential, nM.min) from 586 ± 302 to 509 ± 226 (p = 0.3), 512 ± 270 (p = 0.3) and 445 ± 283 (p < 0.05). These findings indicate that epicatechin affects microparticle release, phenotype and procoagulant properties.
Highlights
Microparticles are small, anucleate vesicles ranging from 100 to 1000 nm in size
Pre-incubation with epicatechin did not have any effect on PMP concentration (PMP/μL) in Platelet-rich plasma (PRP)
Samples incubated with phosphate buffered saline (PBS) (64,153 ± 45,388 for samples incubated with vehicle and 68,726 ± 41,966, 77,864 ± 49,161 and 59,841 ± 29,101 for samples incubated with 1 μM, 10 μM and 100 μM of epicatechin, respectively), with the calcium ionophore
Summary
Microparticles are small, anucleate vesicles ranging from 100 to 1000 nm in size. They are released by many cell types, including platelets, monocytes, red and endothelial cells by exocytosis from the cell membranes upon cell activation, stress or apoptosis [1]. Microparticles are delimited by a phospholipid bilayer and express proteins from the cell of origin [2]. Platelet microparticles (PMPs) represent the main fraction of circulating microparticles and are formed upon platelet activation, glycoprotein (Gp) IIb-IIIa signaling or after exposure to shear stress [6,7]. PMPs express Gp IIb-IIIa (CD41) and Gp Ib (CD42b), phospholipids (e.g., phosphatidylserine (PS) Microparticles are detected in healthy subjects, and their release increases in various pathological conditions, such as cancer, diabetes, sepsis and cardiovascular diseases (CVD) [3,4,5].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
