Investigation of mechanosensing and mechanoresponse mechanisms in osteoblasts and osteocytes: in vitro experiments targeting subcellular components

Abstract

To understand adaptive bone remodeling in response to external mechanical stimuli, researchers have elucidated the mechanisms of mechanosensing and mechanoresponse through in vitro experiments targeting subcellular components from molecules to organelles. Such subcellular experiments have been performed by applying mechanical stimuli to mechanosensitive components and by measuring and observing the dynamic behaviors of the mechanosensitive and mechanoresponsive components. For a better understanding of the importance of the subcellular experiments, this article reviews the recent subcellular experiments for osteoblasts and osteocytes. First, we introduce the tools used for the stimulation and measurement/observation, and we discuss how these tools have contributed to the elucidation of the mechanisms. Second, we shed light on how the findings on the behaviors of the subcellular components have enhanced our basic understanding of the underlying mechanisms. Furthermore, we present future perspectives for subcellular experiments. To do this, we discuss the utilization of microscopes with higher spatial resolution and discuss focus points for a clearer understanding of these mechanisms in osteocytes. Future experiments will reveal how osteoblasts and osteocytes sense and respond to external mechanical stimuli in their surrounding environment in bone, and how cellular behaviors finally lead to the regulation of bone resorption and formation in adaptive bone remodeling.