Vascular endothelial growth factor principally acts as the main angiogenic factor in the early stage of human osteoblastogenesis.
Vascular endothelial growth factor (VEGF)-mediated angiogenesis is essential for bone formation. However, the effect of VEGF on osteoblastic cells during osteoblastogenesis is still controversial. The aim of this study was to clarify the relationship between osteoblastic cells derived from human mesenchymal stem cells (MSCs) and VEGF in the early stage of osteoblastic differentiation. Continuous dexamethasone treatment with a low concentration stimulated osteoblastogenesis of MSCs and the expression of VEGF121 mRNA. The VEGF secretion from osteoblastic cells also increased along with osteoblastogenesis. Neuropilin-1, which mainly binds VEGF165, was detected at all stages during early osteoblastogenesis, but VEGF receptor-1 and -2 were not detected on RT-PCR analyses. In this study, VEGF had no direct effect on the proliferation of osteoblastic cells. However, the secreted VEGF in the conditioned medium of osteoblastic cells exhibited high angiogenic power as to endothelial cell proliferation. Our findings indicated that VEGF121 principally acts as the main angiogenic factor in the early stage of human osteoblastogenesis. The present study also demonstrated the differential expression of VEGF121 during osteoblastogenesis. The increase of VEGF in the early stage might be a useful marker of induction of bone formation due to human MSCs.
Furumatsu
Takayuki
T
Department of Molecular Biology and Biochemistry, Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine and Dentistry, 2-5-1 Shikata-cho, Okayama 700-8558, Japan. takamatino@yahoo.co.jp
Shen
Zheng Nan
ZN
Kawai
Akira
A
Nishida
Keiichiro
K
Manabe
Hironori
H
Oohashi
Toshitaka
T
Inoue
Hajime
H
Ninomiya
Yoshifumi
Y
D000469:Alkaline Phosphatase / Q000096:biosynthesis / Q000235:genetics; D042501:Angiogenic Proteins / Q000502:physiology*; D015415:Biomarkers; D002454:Cell Differentiation / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D003094:Collagen / Q000096:biosynthesis / Q000235:genetics; D003907:Dexamethasone / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D018919:Neovascularization, Physiologic / Q000502:physiology; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D015675:Osteocalcin / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D040262:Receptors, Vascular Endothelial Growth Factor / Q000096:biosynthesis; D042461:Vascular Endothelial Growth Factor A / Q000502:physiology*
D042501:Angiogenic Proteins; D015415:Biomarkers; D012333:RNA, Messenger; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D015675:Osteocalcin; D003907:Dexamethasone; D003094:Collagen; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D040262:Receptors, Vascular Endothelial Growth Factor; D000469:Alkaline Phosphatase