Induction of bone matrix protein expression by native bone matrix proteins in C2C12 culture.
OBJECTIVE
To study the expression of bone matrix protein (BMP) induced by bovine bone morphogenetic proteins (BMPs) in vitro.


METHODS
Type I collagen, osteopontin (OPN), osteonectin (ON), osteocalcin (OC), and bone sialoprotein (BSP) were detected by immunohistochemistry in C2C12 cultured from day 1 to day 28.


RESULTS
The signaling of bone matrix protein expression became weaker except for type I collagen, OC and BSP after 5 days. Fourteen days after culture, the positive signaling of type I collagen, OPN, ON, OC, and BSP was gradually declined, and could be detected significantly as compared with that of the negative control on day 28. BMP assay showed that the alkaline phosphatase (ALP) activity was higher in C2C12 culture than in the control during the 14-day culture. Also, total protein and DNA significantly increased during the 14-day culture. High levels of ALP were seen in preosteoblasts and osteoblasts in vivo and in differentiating osteoblasts in vitro. ALP was well recognized as a marker reflecting osteoblastic activity.


CONCLUSIONS
Native bovine BMP induces conversion of myoblasts into osteoblasts, produces type I collagen, and plays significantly role in osteoinduction and bone matrix mineralization of C2C12 in vitro.
Hu
Zhen-Ming
ZM
Department of Orthopedic Surgery, the First Affiliated Hospital, Chongqing Medical University Chongqing 400016, China. zhenminghu62@yahoo.com.cn
Peel
Sean A F
SA
Ho
Stephen K C
SK
Sandor
George K B
GK
Clokie
Cameron M L
CM
D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001857:Bone Matrix / Q000378:metabolism*; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D002417:Cattle; D002460:Cell Line; D004247:DNA / Q000378:metabolism; D005786:Gene Expression Regulation / Q000502:physiology*; D051379:Mice; D010006:Osteoblasts / Q000187:drug effects* / Q000378:metabolism*
D019485:Bone Morphogenetic Proteins; D004247:DNA; D000469:Alkaline Phosphatase