Factors that promote progressive development of the osteoblast phenotype in cultured fetal rat calvaria cells
Authors
Aronow, Michael A.Gerstenfeld, Louis C.
Owen, Thomas A.
Tassinari, Melissa S.
Stein, Gary S.
Lian, Jane B.
Document Type
Journal ArticlePublication Date
1990-05-01Keywords
Alkaline PhosphataseAnimals
*Bone Development
Calcium
Cell Differentiation
Cells, Cultured
Chickens
Collagen
DNA
Osteoblasts
Osteocalcin
Proteins
Rats
Cell Biology
Metadata
Show full item recordAbstract
Rat calvaria osteoblasts derived from 21-day-old fetal rat pups undergo a temporal expression of markers of the osteoblast phenotype during a 5 week culture period. Alkaline phosphatase and osteocalcin are sequentially expressed in relation to collagen accumulation and mineralization. This pattern of expression of these osteoblast parameters in cultured rat osteoblasts (ROB) is analogous to that seen in vivo in developing fetal rat calvaria tissue (Yoon et. al: Biochem. Biophis. Res. Commun. 148:1129, 1987) and is similar to that observed in cultures of subcultivated 16-day-old embryonic chick calvaria-derived osteoblasts (COB) (Gerstenfeld, et.al: Dev. Biol. 122:46, 1987). While the cellular organization of subcultivated COB and primary ROB cultures are somewhat different, the temporal expression of the parameters remains. Both the rat and chick culture systems support formation of matrix mineralization even in the absence of beta-glycerol-phosphate. A systematic examination of factors which constitute conditions supporting complete expression of the osteoblast phenotype in ROB cultures indicate requirements for specific serum lots, ascorbic acid and the ordered deposition of mineral in the extracellular matrix. The present studies suggest that formation of a collagenous matrix, dependent on ascorbic acid, is requisite for expression of the osteoblast phenotype. In ROB cultures, expression of osteocalcin synthesis occurs subsequent to initiation of alkaline phosphatase activity and accompanies the formation of mineralized nodules. Thus, extracellular matrix mineralization (deposition of hydroxyapatite) is required for complete development of the osteoblast phenotype, as reflected by a 200-fold increase in osteocalcin synthesis. These data show the temporal expression of the various osteoblast parameters during the formation and mineralization of an extracellular matrix can provide markers reflective of various stages of osteoblast differentiation/maturation in vitro.Source
J Cell Physiol. 1990 May;143(2):213-21. Link to article on publisher's siteDOI
10.1002/jcp.1041430203Permanent Link to this Item
http://hdl.handle.net/20.500.14038/49472PubMed ID
2332447Related Resources
Link to Article in PubMedae974a485f413a2113503eed53cd6c53
10.1002/jcp.1041430203