Enhancing fibroblast-based bone regeneration by harnessing nanosecond pulsed electric field

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Cell Biology

Background:

• Human dermal fibroblasts (HDFs) are terminally differentiated cells with potential for bone tissue engineering.
• In vivo, HDFs can undergo osteogenic differentiation, but in vitro replication is challenging.
• Previous studies show low-intensity nanosecond pulsed electric fields (nsPEF) can partially reprogram HDFs and enhance osteogenic capacity.

Purpose of the Study:

• To investigate the efficacy of nsPEF-treated HDFs encapsulated in a self-healing hydrogel for in vivo bone regeneration.
• To elucidate the molecular mechanisms underlying nsPEF-induced osteogenic enhancement in HDFs.

Main Methods:

• Fabrication of an in vivo bone regeneration complex using nsPEF-treated HDFs within an oxidized hyaluronic acid and hydroxypropyl chitosan hydrogel.
• Evaluation of ectopic bone formation in nude mice via subcutaneous and cranial defect implantation.
• Assessment of histological scores, RNA sequencing, Western blot, qPCR, and immunofluorescence to analyze osteogenesis and molecular pathways.

Main Results:

• nsPEF-treated HDFs within the hydrogel significantly enhanced ectopic bone formation compared to controls.
• Accelerated endochondral ossification and activation of the p38 MAPK/YAP pathway were observed in nsPEF-treated HDFs.
• RNA sequencing, qPCR, Western blot, and immunofluorescence validated the enhanced osteogenic transformation.

Conclusions:

• nsPEF stimulation is a potent strategy to improve HDF osteogenic differentiation both in vitro and in vivo.
• This approach holds significant potential for advancing HDF-based bone regeneration strategies.
• The study highlights the role of the p38 MAPK/YAP pathway in nsPEF-mediated osteogenesis.