title: Expression of osteopontin messenger RNA by macrophages in atherosclerotic plaques. A possible association with calcification.
abstract: Calcification is a common complication in atherosclerosis. As osteopontin (OPN) and osteonectin (ON) are not only involved in the physiological but also the pathological calcification of tissues, we examined the expression of OPN and ON messenger (m)RNAs in normal and atherosclerotic human aortas. By Northern blotting, the OPN mRNA expression was related to the severity of the atherosclerosis. However, ON mRNA expression decreased with the development of atherosclerosis. By a combination of in situ hybridization and immunohistochemistry of serial sections, the macrophages surrounding the atheromatous plaques were identified as the OPN mRNA-expressing cells. The ON mRNA-expressing cells in aortas of a newborn baby and a 3-year-old boy were medial smooth muscle cells, but in aortas of adults, smooth muscle cells that had invaded the intima were found to express ON mRNA. As OPN mRNA-expressing macrophages surrounded the atheromatous plaques, and as the level of OPN mRNA expression increased as atherosclerosis advanced, it is possible that OPN plays a role in the calcification of atheromatous plaques.
authors.affiliation: Department of Pathology, Osaka University Medical School, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Hirota
authors.forename: M
authors.initials: M
authors.lastname: Imakita
authors.forename: K
authors.initials: K
authors.lastname: Kohri
authors.forename: A
authors.initials: A
authors.lastname: Ito
authors.forename: E
authors.initials: E
authors.lastname: Morii
authors.forename: S
authors.initials: S
authors.lastname: Adachi
authors.forename: H M
authors.initials: HM
authors.lastname: Kim
authors.forename: Y
authors.initials: Y
authors.lastname: Kitamura
authors.forename: C
authors.initials: C
authors.lastname: Yutani
authors.forename: S
authors.initials: S
authors.lastname: Nomura
mesh_terms: D000368:Aged; D000375:Aging / Q000378:metabolism; D001011:Aorta / Q000378:metabolism; D001161:Arteriosclerosis / Q000150:complications* / Q000378:metabolism* / Q000473:pathology; D015152:Blotting, Northern; D002114:Calcinosis / Q000209:etiology*; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007231:Infant, Newborn; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D053495:Osteopontin; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism*; D012795:Sialoglycoproteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D010750:Phosphoproteins; D012333:RNA, Messenger; C506895:SPP1 protein, human; D012795:Sialoglycoproteins; D053495:Osteopontin