Abstract
Bone remodeling, a process that maintains homeostasis through the activities of osteoclasts and osteoblasts in response to mechanical stimuli, is still not fully understood. This study aims to elucidate a part of this mechanism by establishing osteoblast-like cells derived from the skulls of transgenic mice expressing FRET-based tension sensor, assessing their proliferative and calcification capabilities, and evaluating changes in intracellular tension induced by osteogenic induction medium. Cells were isolated from the calvaria of neonatal FRET mice and passaged in normal medium. A FRET1-MC8 line, which showed superior proliferative capacity, was selected. Calcification capability was evaluated using real-time PCR for bone markers and Alizarin Red S staining. Increased expression of Col1 and Opn under osteogenic condition indicated enhanced differentiation. After two weeks in osteogenic induction medium, calcification was also confirmed via Alizarin Red S staining. Furthermore, intracellular tension changes were monitored by measuring FRET efficiency, which significantly decreased over three days in osteogenic induction medium, indicating an increase in intracellular tension. This cell line expressing the FRET-based tension sensor is expected to contribute to understanding the mechanisms of bone remodeling and to the development of regenerative medicine and treatments for bone diseases.
