Platelet-derived growth factor (PDGF)-AA: a self-imposed cytokine in the proliferation of human fetal osteoblasts.
PDGF, a multiple mitogen, stimulates osteoblast replication and bone collagen degradation, and it has been described as a key factor in bone metabolism. Recently, PDGF was disclosed to be the autocrine cytokine of human osteoblasts. PDGF's effect on human bone development needs elucidation, and the mechanism of PDGF-AA autocrining remains unclear. In this work, osteoblasts were isolated from human fetal calvaria which resemble the cells in developing bone tissue. Using an in vitro model, the effect of PDGF-AA on the cells was investigated with the results showing that (i) after PDGF-AA was added into the medium for 24 h, PCI of the cells increased by 48.2% (P<0.05), and PCI decreased after the removal of PDGF-AA. (ii) 24 h after treatment with PDGF-AA, the percentage of osteoblasts in G(0)/G(1)phase decreased and that in S phase increased. (iii) The expression of PDGF-A mRNA was upregulated by PDGF-AA, PDGF-BB, TGFbeta,and bFGF respectively. These results proved that: (i) PDGF-AA enhances cell replication by accelerating cell recycle and inducing the quiescent cells into the proliferation portion of cell cycle. (ii) PDGF-AA is a self-imposed cytokine in human fetal osteoblast replication.
Yang
D
D
Department of Orthopaedic Surgery, Nanfang Hospital, the First Military Medical University, Guangzhou, 510515, P.R. China.
Chen
J
J
Jing
Z
Z
Jin
D
D
D001846:Bone Development / Q000187:drug effects; D002453:Cell Cycle / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D005333:Fetus; D016222:Fibroblast Growth Factor 2 / Q000502:physiology; D015870:Gene Expression; D006801:Humans; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D010982:Platelet-Derived Growth Factor / Q000235:genetics / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000502:physiology
D010982:Platelet-Derived Growth Factor; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; C075278:platelet-derived growth factor A; D016222:Fibroblast Growth Factor 2