No abstract

We aimed to investigate the effects of dynamic mechanical loading on the expression of osteoblast-and osteoclast-specific genes in regenerating goldfish scales. Fourteen days after the removal of scales from goldfish, the regenerating scales were found to contain calcified tissue, with osteoblasts, osteoclasts, and a newly synthesized calcified bone matrix plate. Recently, we found that goldfish s c a l e r e g e n e r a t i o n s h o w s s i m i l a r g e n e expression to intramembranous mammalian bone osteogenesis. Using such regenerating scales on day 14, we analyzed the effects of dynamic 3G acceleration, via application of a vibration stimulus, on the mRNA expression in osteoblasts and osteoclasts. In osteoblasts, vibration increased distal-less homeobox 5 (an osteoblastic transcriptional gene) mRNA expression at 3 h after stimulation and type I collagen (an osteoblastic functional gene) mRNA expression at 6 h and 12 h after stimulation. Moreover, vibration decreased the mRNA expression of the receptor activator of the NF-κB ligand, which binds to the osteoclast surface receptor and facilitates bone resorption, at 12 h and 24 h after stimulation in osteoblasts. Further, vibration decreased cathepsin K (an osteoclastic functional gene) mRNA expression at 12 h after stimulation. Thus, our results indicate that vibration drives osteoblastic and osteoclastic control of antiresorptive and boneformative effects through mRNA expression.