IGF2 modulates the microenvironment for osteoclastogenesis.
We previously reported that hypoxic stress enhanced osteoclast differentiation via increasing insulin-like growth factor 2 (IGF2) production. However, the mechanisms underlying IGF2 stimulation remains unknown. In this study, we investigated the molecular mechanisms of osteoclastogenesis by IGF2 treatment. Primary mouse bone marrow cells were cultured with IGF2. Total RNAs were applied to a DNA microarray analysis, and quantitative RT-PCR was then used to confirm the microarray data and clarify which cells expressed the relative genes. The most interesting findings were the upregulations of CXC chemokine ligand 7 (CXCL7) expression in stromal cells and stromal cell-derived factor 1 (SDF1) expression in osteoblastic cells with IGF2 treatment. The addition of exogenous SDF1 to CXCL7 increased the number of osteoclasts and promoted the formation of giant osteoclasts. These results suggest that IGF2 modulates the microenvironment around osteoclast precursor cells. SDF1 together with CXCL7 may promote the formation of giant osteoclasts.
Nakao
Kimihisa
K
Department of Orthodontics, School of Dentistry, Aichi-Gakuin University, Chikusa-ku, Nagoya 464-8651, Japan.
Aoyama
Mineyoshi
M
Fukuoka
Hayato
H
Fujita
Masataka
M
Miyazawa
Ken
K
Asai
Kiyofumi
K
Goto
Shigemi
S
D000135:Acid Phosphatase / Q000032:analysis; D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects* / Q000235:genetics; D054377:Chemokine CXCL12 / Q000235:genetics / Q000494:pharmacology; D019743:Chemokines, CXC / Q000235:genetics / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects; D020869:Gene Expression Profiling; D007335:Insulin-Like Growth Factor II / Q000494:pharmacology*; D007527:Isoenzymes / Q000032:analysis; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D020411:Oligonucleotide Array Sequence Analysis; D010010:Osteoclasts / Q000166:cytology*; D000071681:Tartrate-Resistant Acid Phosphatase
D054377:Chemokine CXCL12; D019743:Chemokines, CXC; C446301:Cxcl7 protein, mouse; D007527:Isoenzymes; D007335:Insulin-Like Growth Factor II; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase