Bone Adaptation and Regeneration Regulated by Mechanobiological Stimuli

Mechanical and Aerospace Engineering Department Seminar Series

Bone Adaptation and Regeneration Regulated by Mechanobiological Stimuli

Yi-Xian Qin, Ph.D.
Department of Biomedical Engineering
Stony Brook University, Stony Brook, NY

Mechanotransduction has demonstrated potentials for tissue adaptation in vivo and in vitro. Although a wide range of studies have been done, mechanism for this mechanical effect on bone regeneration is unknown and still under active investigation. A potential mechanism, by which bone cells may sense mechanotransductive signals, is through deformation and streaming of bone cells and their surface structures, to trigger osteogenesis. Our group has recently introduced a non-invasive bone fluid flow (BFF) stimulation using acoustic radiation force (ARF) and found its beneficial effects on bone structural quality in a rat hindlimb suspension model. The objective of this study has two folds, 1) to evaluate the role of mechanobiology in mesenchymal stem cells (MSCs) activation, and 20 have the abilities of self-renewal and differentiation into the cells that form tissues such as bone remodeling and regeneration stem cell response, and 2) quantify Ca2+ oscillations of in-situ osteocytes in real-time response to medium-intensity acoustic radiation force (ARF).  It was demonstrated that MSCs have the abilities of self-renewal and differentiation as longitudinal time dependent activation. While in situ osteocytes show unique Ca2+ oscillations to fluid shear, frequency dependent Ca2+ oscillations in osteocytes indicated the optimized loading at 10Hz, where such induced response was significantly diminished via blockage of the Wnt/-catenin signaling pathway. The results suggested a potential crosstalk or interaction between Wnt/β-catenin signaling and Ca2+ influx signaling of in situ osteocytes in response to mechanical signals.

Biosketch
Dr. Yi-Xian Qin is Professor of Biomedical Engineering and Orthopaedics, the Director of Orthopaedic Bioengineering Research Laboratory at Stony Brook University, and a founding faculty member of BME. He is a Fellow of the American Institute of Medicine and Biological Engineering (AIMBE), and Member of the International Astronautics Academy (IAA). His research has been focused on musculoskeletal tissue regeneration and translation through physical regulation and characterization of tissue quality, as well as evaluating the mechanisms responsible for tissue remodeling. The laboratory is currently interested in the areas of bone tissue engineering, mitigation of bone loss, implant fixation, bone fluid flow controlled bone remodeling and cellular activities, promotion of fracture healing and regeneration, and ultrasonic diagnostics and therapeutics for osteopenia and fracture. The lab has extensive experience in cellular culture and mechanistic evaluation, various in vivo models, and ultrasound imaging. His work has been continuously funded by NIH, DOD, NASA/NSBRI, and industries for the last two decades. He served as Chair of the Cellular and Molecular Bioengineering Special Int. Group of the Biomedical Engineering Society (BMES), and Board of Chair of ICMRS. He has published more than 100 peer-reviewed paper and book chapters in musculoskeletal research journals and books.