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Title: Small GTPase Rho signaling is involved in {beta}1 integrin-mediated up-regulation of intercellular adhesion molecule 1 and receptor activator of nuclear factor {kappa}B ligand on osteoblasts and osteoclast maturation

Abstract

We assessed the characteristics of human osteoblasts, focusing on small GTPase Rho signaling. {beta}1 Integrin were highly expressed on osteoblasts. Engagement of {beta}1 integrins by type I collagen augmented expression of intercellular adhesion molecule 1 (ICAM-1) and receptor activator of nuclear factor {kappa}B ligand (RANKL) on osteoblasts. Rho was activated by {beta}1 stimulation in osteoblasts. {beta}1 Integrin-induced up-regulation of ICAM-1 and RANKL was inhibited by transfection with adenoviruses encoding C3 transferase or pretreated with Y-27632, specific Rho and Rho-kinase inhibitors. Engagement of {beta}1 integrin on osteoblasts induced formation of tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells (MNC) in a coculture system of osteoblasts and peripheral monocytes, but this action was completely abrogated by transfection of C3 transferase. Our results indicate the direct involvement of Rho-mediated signaling in {beta}1 integrin-induced up-regulation of ICAM-1 and RANKL and RANKL-dependent osteoclast maturation. Thus, Rho-mediated signaling in osteoblasts seems to introduce major biases to bone resorption.

Authors:
 [1];  [1];  [1];  [1];  [2];  [3];  [4]
  1. First Department of Internal Medicine, University of Occupational and Environmental Health, School of Medicine, Kitakyushu 807-8555 (Japan)
  2. Department of Pharmacology and Toxicology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan)
  3. Pharmaceuticals Research Unit Research and Development Division Mitsubishi Pharma Corporation, Kamoshida-cho, Aoba-ku, Yokohama 227-0033 (Japan)
  4. First Department of Internal Medicine, University of Occupational and Environmental Health, School of Medicine, Kitakyushu 807-8555 (Japan). E-mail: tanaka@med.uoeh-u.ac.jp
Publication Date:
OSTI Identifier:
20991318
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 356; Journal Issue: 1; Other Information: DOI: 10.1016/j.bbrc.2007.02.121; PII: S0006-291X(07)00428-7; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; ACID PHOSPHATASE; ADENOVIRUS; ADHESION; CELL PROLIFERATION; COLLAGEN; CONNECTIVE TISSUE CELLS; GENE REGULATION; LIGANDS; MONOCYTES; RECEPTORS; SKELETON

Citation Formats

Hirai, Fumihiko, Nakayamada, Shingo, Okada, Yosuke, Saito, Kazuyoshi, Kurose, Hitoshi, Mogami, Akira, and Tanaka, Yoshiya. Small GTPase Rho signaling is involved in {beta}1 integrin-mediated up-regulation of intercellular adhesion molecule 1 and receptor activator of nuclear factor {kappa}B ligand on osteoblasts and osteoclast maturation. United States: N. p., 2007. Web. doi:10.1016/j.bbrc.2007.02.121.
Hirai, Fumihiko, Nakayamada, Shingo, Okada, Yosuke, Saito, Kazuyoshi, Kurose, Hitoshi, Mogami, Akira, & Tanaka, Yoshiya. Small GTPase Rho signaling is involved in {beta}1 integrin-mediated up-regulation of intercellular adhesion molecule 1 and receptor activator of nuclear factor {kappa}B ligand on osteoblasts and osteoclast maturation. United States. doi:10.1016/j.bbrc.2007.02.121.
Hirai, Fumihiko, Nakayamada, Shingo, Okada, Yosuke, Saito, Kazuyoshi, Kurose, Hitoshi, Mogami, Akira, and Tanaka, Yoshiya. Fri . "Small GTPase Rho signaling is involved in {beta}1 integrin-mediated up-regulation of intercellular adhesion molecule 1 and receptor activator of nuclear factor {kappa}B ligand on osteoblasts and osteoclast maturation". United States. doi:10.1016/j.bbrc.2007.02.121.
@article{osti_20991318,
title = {Small GTPase Rho signaling is involved in {beta}1 integrin-mediated up-regulation of intercellular adhesion molecule 1 and receptor activator of nuclear factor {kappa}B ligand on osteoblasts and osteoclast maturation},
author = {Hirai, Fumihiko and Nakayamada, Shingo and Okada, Yosuke and Saito, Kazuyoshi and Kurose, Hitoshi and Mogami, Akira and Tanaka, Yoshiya},
abstractNote = {We assessed the characteristics of human osteoblasts, focusing on small GTPase Rho signaling. {beta}1 Integrin were highly expressed on osteoblasts. Engagement of {beta}1 integrins by type I collagen augmented expression of intercellular adhesion molecule 1 (ICAM-1) and receptor activator of nuclear factor {kappa}B ligand (RANKL) on osteoblasts. Rho was activated by {beta}1 stimulation in osteoblasts. {beta}1 Integrin-induced up-regulation of ICAM-1 and RANKL was inhibited by transfection with adenoviruses encoding C3 transferase or pretreated with Y-27632, specific Rho and Rho-kinase inhibitors. Engagement of {beta}1 integrin on osteoblasts induced formation of tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells (MNC) in a coculture system of osteoblasts and peripheral monocytes, but this action was completely abrogated by transfection of C3 transferase. Our results indicate the direct involvement of Rho-mediated signaling in {beta}1 integrin-induced up-regulation of ICAM-1 and RANKL and RANKL-dependent osteoclast maturation. Thus, Rho-mediated signaling in osteoblasts seems to introduce major biases to bone resorption.},
doi = {10.1016/j.bbrc.2007.02.121},
journal = {Biochemical and Biophysical Research Communications},
number = 1,
volume = 356,
place = {United States},
year = {Fri Apr 27 00:00:00 EDT 2007},
month = {Fri Apr 27 00:00:00 EDT 2007}
}
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