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Communication dans un congrès

Microparticles from activated/apoptotic lymphocytes preserve endothelial cell integrity

Abstract :

Microparticles (MPs), small membrane-derived fragments shed from various cell types during activation and/or apoptosis, represent a new class of biological information mediators. MPs generated from T lymphocytes undergoing activation and apoptosis exert a beneficial potential effect on the cardiovascular system through their dual capacity to increase nitric oxide and reduce reactive oxygen species production. This study investigated the effect of MPs on both the angiogenesis and apoptosis of human umbilical vein endothelial cells. MPs induced the formation of capillary-like structures in an in vitro model, by regulating cell proliferation. Both cell adhesion and expression of proteins involved in this process, such as Rho A, and phosphorylation of focal-activated kinase were increased by MPs, via a ROCK inhibitor-sensitive pathway. MPs increased mRNA and protein levels of pro-angiogenic factors as measured by qRT-PCR and western blot. MPs significantly attenuated the increase in reactive oxygen species (ROS) associated with Act D-induced apoptosis at early phase of apoptosis (2 h), by acting directly as ROS scavengers, owing to their ability to carry active antioxidant enzymes such as catalase and the 3 isoforms of the superoxide dismutase. Furthermore, the effects of MPs on the late phases of apoptosis were associated with the ability of these vesicles to increase the expression of manganese-superoxide dismutase through internalisation process. Interestingly, the effects induced by MPs on the formation of capillary-like structures, expression of adhesion molecules and pro-angiogenic factors and on apoptosis were reversed when Sonic Hedgehog signalling was pharmacologically inhibited with cyclopamine. These findings illustrate new mechanisms by which MPs from T lymphocytes exert their vasculo-protective effects by improving endothelial function under pathological conditions in which cell integrity is impaired.

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Communication dans un congrès
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Contributeur : Okina Univ Angers Connectez-vous pour contacter le contributeur
Soumis le : vendredi 2 juillet 2021 - 11:57:38
Dernière modification le : mercredi 19 janvier 2022 - 16:22:03

Lien texte intégral




Ramaroson Andriantsitohaina, Raffaella Soleti, Tarek Benameur, Emilie Lauret, Maria Carmen Martinez. Microparticles from activated/apoptotic lymphocytes preserve endothelial cell integrity. International Society of Extracellular Vesicles, 2013, Boston, États-Unis. pp.20826, ⟨10.3402/jev.v2i0.20826⟩. ⟨hal-03276662⟩



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