title: Endochondral bone formation is involved in media calcification in rats and in men.
abstract: Arterial media calcification is often considered a cell-regulated process resembling intramembranous bone formation, implying a conversion of vascular tissue into a bone-like structure without a cartilage intermediate. In this study, we examined the association of chondrocyte-specific marker expression with media calcification in arterial samples derived from rats with chronic renal failure (CRF) and from human transplant donors. CRF was induced in rats with a diet supplemented with adenine. Vascular calcification was evaluated histomorphometrically on Von Kossa-stained sections and the expression of the chondrocyte markers sox9 and collagen II with the osteogenic marker core-binding factor alpha1 (cbfa1) was determined immunohistochemically. Media calcification was detected in more than half of the rats with CRF. In over half of the rats with severe media calcification, a typical cartilage matrix was found by morphology. All of the animals with severe calcification showed the presence of chondrocyte-like cells expressing the markers sox9, collagen II, and cbfa1. Human aorta specimens showing mild to moderate media calcification also showed sox9, collagen II, and cbfa1 expression. The presence of chondrocytes in association with calcification of the media in aortas of rats with CRF mimics endochondral bone formation. The relevance of this association is further demonstrated by the chondrogenic conversion of medial smooth muscle cells in the human aorta.
authors.affiliation: Department of Pathophysiology, University of Antwerp, Universiteitsplein 1, 2619 Wilrijk, Belgium.
authors.forename: E
authors.initials: E
authors.lastname: Neven
authors.forename: S
authors.initials: S
authors.lastname: Dauwe
authors.forename: M E
authors.initials: ME
authors.lastname: De Broe
authors.forename: P C
authors.initials: PC
authors.lastname: D'Haese
authors.forename: V
authors.initials: V
authors.lastname: Persy
mesh_terms: D000818:Animals; D001011:Aorta / Q000166:cytology; D015415:Biomarkers / Q000032:analysis; D001808:Blood Vessels / Q000378:metabolism / Q000473:pathology*; D002114:Calcinosis; D019902:Chondrocytes; D024043:Collagen Type II / Q000032:analysis; D050659:Core Binding Factor Alpha 1 Subunit / Q000032:analysis; D006244:Hardness; D006609:High Mobility Group Proteins / Q000032:analysis; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000473:pathology; D008297:Male; D032389:Myocytes, Smooth Muscle / Q000166:cytology; D010012:Osteogenesis; D051381:Rats; D017208:Rats, Wistar; D055758:SOX9 Transcription Factor; D014157:Transcription Factors / Q000032:analysis; D014652:Vascular Diseases / Q000209:etiology* / Q000473:pathology
chemical_list: D015415:Biomarkers; D024043:Collagen Type II; D050659:Core Binding Factor Alpha 1 Subunit; D006609:High Mobility Group Proteins; D055758:SOX9 Transcription Factor; C527932:SOX9 protein, human; D014157:Transcription Factors