Characterization of the Angiogenic and Proteomic Features of Circulating Exosomes in a Canine Mandibular Model of Distraction Osteogenesis

Distraction osteogenesis (DO) represents a highly effective
method
for addressing significant bone defects; however, it necessitates
a long treatment period. Exosomes are key mediators of intercellular
communication. To investigate their role in the angiogenesis and osteogenesis
of DO, we established a canine mandibular DO model with a bone defect
(BD) group as the control. Higher levels of angiogenesis were observed
in the regenerating tissue from the DO group compared to those from
the BD group, accompanied by earlier osteogenesis. Proteomic analysis
was performed on circulating exosomes at different phases of the DO
using a data-independent acquisition method. Data are available via ProteomeXchange with the identifier PXD050531. The results
indicated specific alterations in circulating exosome proteins at
different phases of DO, reflecting the regenerative activities in
the corresponding tissues. Notably, fibronectin 1 (FN1), thrombospondin
1 (THBS1), and transferrin receptor (TFRC) emerged as potential candidate
proteins related to the angiogenic response in DO. Further cellular
experiments validated the potential of DO-associated circulating exosomes
to promote angiogenesis in endothelial cells. Collectively, these
data reveal previously unknown mechanisms that may underlie the efficacy
of DO and suggest that exosome-derived proteins may be useful as therapeutic
targets for strategies designed to improve DO-related angiogenesis
and bone regeneration.