Title: Bone Remodeling at 2015: from Repair, Healing, Adaptation, to Regeneration
Andy Y-T. Teng;
Center for Osteoimmunology and Biotechnology
Research (COBR), College of Dental Medicine, Kaohsiung
Medical University, Kaohsiung, Taiwan
Abstract:
It is now clear that bone is dynamically
modulated by its multi-cellular unit (BMU), interconnected through the hierarchy
of trabecular system leveled to subcellular-molecular laculo-canalicular structures,
made of live osteoblasts (OB), pre-OB, osteocytes & bone-lining cells,
osteoclasts (OC) & OC precursors, and the matrix-mesenchyme as well; each
of which contribute to the activities of skeletal-bone remodeling compartment
(BRC). In human’s skeleton, the basic modeling
and remodeling processes are physiologically orchestrated by an arrayed
constellation of intrinsic vs. extrinsic regulatory signals (e.g., RANKL-RANK/OPG,
JAK-STATS, etc.) via specific chemokines,
cytokines (i.e., TGF-b & IL-17/23, etc.),
peptides and hormones (i.e., PTH, estrogens), physical activities (i.e., dynamic
loading or exercises) in comparison to physiologic vs. pathogenic constrains,
that fine-tune the balanced outcomes from any biological events yielding to bone
repair, adaptation, united healing, or regeneration in BMU. Upon triggering mechano-loading or stress-related
damages, unique signals are molecule-sensed by the osteocyte network, followed
by recruitment of OC precursors, signifying the resorbing matrix products in the
BRC to modulate such cycling events towards activated (re)-modeling machinery resulting
in a net gain or loss of the bone in-volumes (from bio-synthesis, repair, adaptive
changes to destruction or regeneration) throughout the BMU in its life time.
This oral presentation will feature a
summative perspective of some critical clinical entities, such as the MRONJ, wound
healing in bone & osteomyelitis, peri-implantitis, and mesenchymal stem
cells for bone regeneration at the osteo-immune interface regarding the key
osteotropic cytokines/factors in relation to skeletal (re)-modeling involved in
the osteoporotic conditions and the cancer-to-bone metastasis. Moreover,
highlight on the links between RANKL-RANK/OPG triads and molecular engineering
for potent bone regeneration will also be briefly elucidated for future
perspective.
