title: Effects of low-intensity pulsed ultrasound on osteoclasts: Analysis with goldfish scales as a model of bone.
abstract: The effects of low-intensity pulsed ultrasound (LIPUS) on osteoclastogenesis were examined using fish scales that had both osteoclasts and osteoblasts. The binding of the receptor activator of NF-κB ligand (RANKL) in osteoblasts to the receptor activator of NF-κB (RANK) in osteoclasts induced osteoclastogenesis. Therefore, we focused on RANK/RANKL signaling. After 6 h of incubation following LIPUS treatment, mRNA expression of RANKL increased significantly. Resulting from the increased RANKL mRNA level, the expression of transcription-regulating factors significantly increased after 6 h of incubation, and then the mRNA expression of functional genes was significantly up-regulated after 12 h of incubation. However, the mRNA expression of osteoprotegerin (OPG), which is known as an osteoclastogenesis inhibitory factor, also significantly increased after 6 h of incubation and tended to further increase after 12 h of incubation. At 24 h of incubation, osteoclastic functional genes' mRNA expression decreased to the level of the control. Furthermore, we performed an in vivo experiment with goldfish. Two weeks after daily LIPUS exposure, osteoclastic marker enzymes tended to decrease while osteoblastic marker enzymes were activated. The regeneration rate of the LIPUS-treated scales was significantly higher than that of the control scales. Thus, LIPUS moderately activates osteoclasts and induces bone formation.
authors.affiliation: Noto Marine Laboratory, Division of Marine Environmental Studies, Institute of Nature and Environmental Technology, Kanazawa University.
authors.forename: Taizo
authors.initials: T
authors.lastname: Hanmoto
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Tabuchi
authors.forename: Mika
authors.initials: M
authors.lastname: Ikegame
authors.forename: Takashi
authors.initials: T
authors.lastname: Kondo
authors.forename: Kei-Ichiro
authors.initials: KI
authors.lastname: Kitamura
authors.forename: Masato
authors.initials: M
authors.lastname: Endo
authors.forename: Isao
authors.initials: I
authors.lastname: Kobayashi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Mishima
authors.forename: Toshio
authors.initials: T
authors.lastname: Sekiguchi
authors.forename: Makoto
authors.initials: M
authors.lastname: Urata
authors.forename: Azusa
authors.initials: A
authors.lastname: Seki
authors.forename: Sachiko
authors.initials: S
authors.lastname: Yano
authors.forename: Atsuhiko
authors.initials: A
authors.lastname: Hattori
authors.forename: Nobuo
authors.initials: N
authors.lastname: Suzuki
mesh_terms: D000818:Animals; D001862:Bone Resorption; D001842:Bone and Bones / Q000502:physiology*; D005260:Female; D005819:Genetic Markers; D006054:Goldfish; D008297:Male; D023421:Models, Animal; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism; D010006:Osteoblasts / Q000502:physiology; D010010:Osteoclasts / Q000502:physiology*; D010012:Osteogenesis; D053244:Osteoprotegerin / Q000235:genetics / Q000378:metabolism; D053245:RANK Ligand / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D000069453:Ultrasonic Waves
chemical_list: D005819:Genetic Markers; D016328:NF-kappa B; D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger