Abstract
Perimenopausal period causes a significant amount of bone loss, which results in
primary osteoporosis (OP). The Periostin (Postn) may play important roles in the
pathogenesis of OP after ovariectomized (OVX) rats. To identify the roles of
Postn in the bone marrow mesenchymal stem cell derived osteoblasts (BMSC-OB) in
OVX rats, we investigated the expression of Wnt/β-catenin
signaling pathways in BMSC-OB and the effects of Postn on bone formation by
development of BMSC-OB cultures. Twenty-four female Sprague–Dawley rats
at 6 months were randomized into 3 groups: sham-operated (SHAM) group, OVX group
and OVX+Postn group. The rats were killed after 3 months, and their
bilateral femora and tibiae were collected for BMSC-OB culture, Micro-CT
Analysis, Bone Histomorphometric Measurement, Transmission Electron Microscopy
and Immunohistochemistry Staining. The dose/time-dependent effects of
Postn on the proliferation, differentiation and mineralization of BMSC-OB and
the expression of osteoblastic markers were measured in in vitro experiments. We
found increased Postn increased bone mass, promoted bone formation of
trabeculae, Wnt signaling and the osteogenic activity in osteoblasts in
sublesional femur. Postn have the function to enhance cell proliferation,
differentiation and mineralization at a proper concentration and incubation
time. Interestingly, in BMSC-OB from OVX rats treated with the different dose of
Postn, the osteoblastic markers expression and Wnt/β-catenin
signaling pathways were significantly promoted. The direct effect of Postn may
lead to inhibit excessive bone resorption and increase bone formation through
the Wnt/β-catenin signaling pathways after OVX. Postn may play a
very important role in the pathogenesis of OP after OVX.
Keywords
osteoporosis - periostin - osteoblast
