Reference - Detail
|Author||Bandow K, Nishikawa Y, Ohnishi T, Kakimoto K, Soejima K, Iwabuchi S, Kuroe K, Matsuguchi T.|
|Title||Low-intensity pulsed ultrasound (LIPUS) induces RANKL, MCP-1, and MIP-1beta expression in osteoblasts through the angiotensin II type 1 receptor.|
|Journal||J. Cell. Physiol.|
Constant mechanical stress is essential for the maintenance of bone mass and strength, which is achieved through the cooperative functions of osteoblasts and osteoclasts. However, it has not been fully elucidated how these cell types mediate mechanical signals. Low-intensity pulsed ultrasound (LIPUS) therapy is a recently developed method for application of mechanical stress, and is used clinically to promote bone fracture healing. In the present study, we applied LIPUS to osteoblasts at different stages of maturation and analyzed their chemokine and cytokine expression. In comparison with their immature counterparts, mature osteoblasts expressed significantly higher levels of mRNAs for the receptor activator of nuclear factor kappa B ligand (RANKL), monocyte chemoattractant protein (MCP)-1, and macrophage-inflammatory protein (MIP)-1beta after a few hours of LIPUS treatment. Intriguingly, protein and mRNA expression of angiotensin II type 1 receptor (AT1), a known mechanoreceptor in cardiomyocytes, was detected in osteoblasts, and the level of expression increased significantly during cell maturation. Furthermore, LIPUS-induced extracellular signal-regulated kinase (ERK) phosphorylation and RANKL/chemokine expression was abrogated by a specific AT1 inhibitor. Thus, AT1 may play one of the essential roles in bone metabolism as a mechanoreceptor of osteoblasts.
|MeSH||Angiotensin II Type 1 Receptor Blockers / pharmacology Animals Benzimidazoles / pharmacology Cell Differentiation Chemokine CCL2 / biosynthesis* Chemokine CCL2 / genetics Chemokine CCL4 Chemokine CCL5 / genetics Chemokine CCL5 / metabolism Chemokines, CC / biosynthesis* Chemokines, CC / genetics Extracellular Signal-Regulated MAP Kinases / metabolism Mechanotransduction, Cellular* Mice Osteoblasts / cytology Osteoblasts / drug effects Osteoblasts / metabolism* Osteoprotegerin / genetics Osteoprotegerin / metabolism Phosphorylation RANK Ligand / biosynthesis* RANK Ligand / genetics RNA, Messenger / biosynthesis Receptor, Angiotensin, Type 1 / biosynthesis* Receptor, Angiotensin, Type 1 / drug effects Receptor, Angiotensin, Type 1 / genetics Stress, Mechanical Tetrazoles / pharmacology Time Factors Ultrasonic Therapy* / methods Up-Regulation|
|WOS Category||PHYSIOLOGY CELL BIOLOGY|
|Human and Animal Cells|