Sensorineural regulation of skull healing implicates FGF1 signaling in non-healing bone

Horenberg, A. L.; Villapudua-Gastelum, C.; Xu, M.; Zeng, E.; Dias, S.; Sinha, T.; Archer, M.; Scheller, E. L.; Pathak, A.; James, A.; Grayson, W.

doi:10.1101/2025.11.24.690319

bioRxiv · 10.1101/2025.11.24.690319

Sensorineural regulation of skull healing implicates FGF1 signaling in non-healing bone

Horenberg, A. L.·Villapudua-Gastelum, C.·Xu, M.·Zeng, E.·Dias, S.·Sinha, T.·Archer, M.·Scheller, E. L.·Pathak, A.·James, A.·Grayson, W.

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Abstract

Bone injuries demonstrate rapid peripheral nerve ingrowth followed by nerve pruning as healing ensues. However, in non-healing bone injuries, peripheral innervation remains elevated, the implications of which remain unknown. Therefore, we investigated the neuroskeletal microenvironment in subcritical-and critical-sized calvarial defects using quantitative 3D fluorescence imaging. We identified elevated densities of peripheral nerves and Osterix positive (Osx+) osteoprogenitors in critical-sized defects, while osteogenic differentiation markers were severely diminished. Moreover, Osx+ osteoprogenitors in critical-sized defects exhibited enhanced proximity to peripheral nerves, which in turn was associated with increased osteoprogenitor cell proliferation. Using retrograde tracing in conjunction with single cell RNA-sequencing of sensory nerves from the innervating trigeminal ganglia, genes encoding for nerve-secreted proliferative and anti-differentiation factors were identified. Specifically, FGF-1/FGFR-1 signaling was identified as a significant neuroskeletal interaction with critical-sized defects demonstrating higher FGF-1 expression in fluorescence imaging. Presence of FGF-1 in neurons innervating the calvarial was confirmed, and neural conditioned media depleted for FGF1 showed enhanced induction of osteogenesis when placed on parietal bone cells. Collectively, we identify a sensorineural-skeletal signaling interaction elevated in critical-sized defects that can be leveraged as a potential therapeutic target for enhancing bone healing.

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Horenberg, A. L., Villapudua-Gastelum, C., Xu, M., Zeng, E., Dias, S., Sinha, T., Archer, M., Scheller, E. L., Pathak, A., James, A., Grayson, W.. 2025-11-28. Sensorineural regulation of skull healing implicates FGF1 signaling in non-healing bone. https://doi.org/10.1101/2025.11.24.690319

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