Introduction
Osteoarthritis (OA) is considered as a whole joint disease. The close physical
association between subchondral bone and cartilage suggests the existence of
biochemical and molecular crosstalk across the bone-cartilage interface, which may
even be elevated in OA [1]
[2]. miR-221-3p was demonstrated to be
mechanosensitive in cartilage chondrocytes and extracellular vesicles (EVs) have
been deeply researched for a specific role in cell-cell communication [3]
[4]
[5]. The present study is to investigate the
communication between chondrocytes and osteoblasts through miR-221-3p transferred
via EVs.
Material and Methods
Chondrocytes and osteoblasts were isolated from newborn rats. EVs were isolated by
differential ultracentrifugation. Nanoparticle tracking analysis, western blot
analysis and transmission electron microscopy were used to identify EVs.
Chondrocytes and osteoblasts were cocultured in transwell and qRT-PCR was used to
assess their communication. Osteoblasts were treated with EVs isolated from
chondrocytes and results were evaluated by histochemistry methods and qRT-PCR.
Results
Collagen II immunofluorescence was positive in chondrocytes and mineralized nodule
formation of osteoblasts was illustrated by Von Kossa and Alizarin red staining.
miR-221-3p was transferred by EVs from chondrocytes to osteoblasts in our coculture
transwell approach. Furthermore, qRT-PCR and Alizarin red staining demonstrated a
decreased osteogenic capacity of osteoblasts treated with miR-221-3p loaded EVs.
Conclusion
This study provides a novel perspective on the
mechanotransductive effect of miR-221-3p between chondrocytes and
osteoblasts' communication through EVs. These results build the basis to
modulate bone-cartilage remodeling and communication in the
future.
