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Stage-Specific Secretion of HMGB1 in Cartilage Regulates Endochondral Ossification.

Authors :
Taniguchi, Noboru
Yoshida, Kenji
Ito, Tatsuo
Tsuda, Masanao
Mishima, Yasunori
Furumatsu, Takayuki
Ronfani, Lorenza
Abeyama, Kazuhiro
Kawahara, Ko-ichi
Komiya, Setsuro
Maruyama, Ikuro
Lotz, Martin
Bianchi, Marco E.
Asahara, Hiroshi
Source :
Molecular & Cellular Biology. Aug2007, Vol. 27 Issue 16, p5-5. 1p.
Publication Year :
2007

Abstract

High mobility group box 1 protein (HMGB1) is a chromatin protein that has a dual function as a nuclear factor and as an extracellular factor. Extracellular HMGB1 released by damaged cells acts as a chemoattractant, as well as a proinflammatory cytokine, suggesting that HMGB1 is tightly connected to the process of tissue organization. However, the role of HMGB1 in bone and cartilage that undergo remodeling during embryogenesis, tissue repair, and disease is largely unknown. We show here that the stage-specific secretion of HMGB1 in cartilage regulates endochondral ossification. We analyzed the skeletal development of Hmgb1-/- mice during embryogenesis and found that endochondral ossification is significantly impaired due to the delay of cartilage invasion by osteoclasts, osteoblasts, and blood vessels. Immunohistochemical analysis revealed that HMGB1 protein accumulated in the cytosol of hypertrophic chondrocytes at growth plates, and its extracellular release from the chondrocytes was verified by organ culture. Furthermore, we demonstrated that the chondrocyte-secreted HMGB1 functions as a chemoattractant for osteoclasts and osteoblasts, as well as for endothelial cells, further supporting the conclusion that Hmgb1-/- mice are defective in cell invasion. Collectively, these findings suggest that HMGB1 released from differentiating chondrocytes acts, at least in part, as a regulator of endochondral ossification during osteogenesis. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
02707306
Volume :
27
Issue :
16
Database :
Academic Search Index
Journal :
Molecular & Cellular Biology
Publication Type :
Academic Journal
Accession number :
26113758
Full Text :
https://doi.org/10.1128/MCB.00130-07