title: Endothelial microparticles mediate inflammation-induced vascular calcification.
abstract: Stimulation of endothelial cells (ECs) with TNF-α causes an increase in the expression of bone morphogenetic protein-2 (BMP-2) and the production of endothelial microparticles (EMPs). BMP-2 is known to produce osteogenic differentiation of vascular smooth muscle cells (VSMCs). It was found that EMPs from TNF-α-stimulated endothelial cells (HUVECs) contained a significant amount of BMP-2 and were able to enhance VSMC osteogenesis and calcification. Calcium content was greater in VSMCs exposed to EMPs from TNF-α-treated HUVECs than EMPs from nontreated HUVECs (3.56 ± 0.57 vs. 1.48 ± 0.56 µg/mg protein; P < 0.05). The increase in calcification was accompanied by up-regulation of Cbfa1 (osteogenic transcription factor) and down-regulation of SM22α (VSMC lineage marker). Inhibition of BMP-2 by small interfering RNA reduced the VSMC calcification induced by EMPs from TNF-α-treated HUVECs. Similar osteogenic capability was observed in EMPs from both patients with chronic kidney disease and senescent cells, which also presented a high level of BMP-2 expression. Labeling of EMPs with CellTracker shows that EMPs are phagocytized by VSMCs under all conditions (with or without high phosphate, control, and EMPs from TNF-α-treated HUVECs). Our data suggest that EC damage results in the release of EMPs with a high content of calcium and BMP-2 that are able to induce calcification and osteogenic differentiation of VSMCs.
authors.affiliation: Instituto Maimónides de Investigación Biomédica de Córdoba/Fundación de Investigaciones Biomédicas de Córdoba, Reina Sofía University Hospital, Córdoba, Spain; Redes Temáticas de Investigación Cooperativa en Salud Renal, Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Paula
authors.initials: P
authors.lastname: Buendía
authors.affiliation: Instituto Maimónides de Investigación Biomédica de Córdoba/Fundación de Investigaciones Biomédicas de Córdoba, Reina Sofía University Hospital, Córdoba, Spain; Redes Temáticas de Investigación Cooperativa en Salud Renal, Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Addy
authors.initials: A
authors.lastname: Montes de Oca
authors.affiliation: Instituto Maimónides de Investigación Biomédica de Córdoba/Fundación de Investigaciones Biomédicas de Córdoba, Reina Sofía University Hospital, Córdoba, Spain;
authors.forename: Juan Antonio
authors.initials: JA
authors.lastname: Madueño
authors.affiliation: Redes Temáticas de Investigación Cooperativa en Salud Renal, Instituto de Salud Carlos III, Madrid, Spain Laboratory of Experimental Nephrology, IDIBELL, Hospital Universitari de Bellvitge, L'Hospitalet, Barcelona, Spain;
authors.forename: Ana
authors.initials: A
authors.lastname: Merino
authors.affiliation: Instituto Maimónides de Investigación Biomédica de Córdoba/Fundación de Investigaciones Biomédicas de Córdoba, Reina Sofía University Hospital, Córdoba, Spain; Redes Temáticas de Investigación Cooperativa en Salud Renal, Instituto de Salud Carlos III, Madrid, Spain Nephrology Unit, Reina Sofía University Hospital, Córdoba, Spain;
authors.forename: Alejandro
authors.initials: A
authors.lastname: Martín-Malo
authors.affiliation: Instituto Maimónides de Investigación Biomédica de Córdoba/Fundación de Investigaciones Biomédicas de Córdoba, Reina Sofía University Hospital, Córdoba, Spain; Redes Temáticas de Investigación Cooperativa en Salud Renal, Instituto de Salud Carlos III, Madrid, Spain Nephrology Unit, Reina Sofía University Hospital, Córdoba, Spain;
authors.forename: Pedro
authors.initials: P
authors.lastname: Aljama
authors.affiliation: Nephrology Unit, Reina Sofía University Hospital, Córdoba, Spain; Redes Temáticas de Investigación Cooperativa en Salud Renal, Instituto de Salud Carlos III, Madrid, Spain Physiology Department, Alcalá de Henares University, Madrid, Spain; and.
authors.forename: Rafael
authors.initials: R
authors.lastname: Ramírez
authors.affiliation: Instituto Maimónides de Investigación Biomédica de Córdoba/Fundación de Investigaciones Biomédicas de Córdoba, Reina Sofía University Hospital, Córdoba, Spain; Redes Temáticas de Investigación Cooperativa en Salud Renal, Instituto de Salud Carlos III, Madrid, Spain Nephrology Unit, Reina Sofía University Hospital, Córdoba, Spain; juanm.rodriguez.sspa@juntadeandalucia.es.
authors.forename: Mariano
authors.initials: M
authors.lastname: Rodríguez
authors.affiliation: Instituto Maimónides de Investigación Biomédica de Córdoba/Fundación de Investigaciones Biomédicas de Córdoba, Reina Sofía University Hospital, Córdoba, Spain; Redes Temáticas de Investigación Cooperativa en Salud Renal, Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Julia
authors.initials: J
authors.lastname: Carracedo
mesh_terms: D017304:Annexin A5 / Q000378:metabolism; D055396:Bone Morphogenetic Protein 2 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D055252:Cell-Derived Microparticles / Q000378:metabolism* / Q000473:pathology; D002478:Cells, Cultured; D016922:Cellular Senescence; D042783:Endothelial Cells / Q000378:metabolism* / Q000473:pathology; D055785:Gene Knockdown Techniques; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D007249:Inflammation / Q000378:metabolism / Q000473:pathology; D032389:Myocytes, Smooth Muscle / Q000378:metabolism / Q000473:pathology; D016328:NF-kappa B / Q000378:metabolism; D010012:Osteogenesis; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000378:metabolism / Q000473:pathology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D061205:Vascular Calcification / Q000209:etiology* / Q000378:metabolism / Q000473:pathology
chemical_list: D017304:Annexin A5; C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; D002118:Calcium
keywords: BMP-2 osteogenic differentiation; HUVECs; TNF-α; VSMC calcification