Dextromethorphan Inhibits Osteoblast Differentiation and Bone Regeneration of Rats With Subcritical-Sized Calvarial...

Area of Science:

• Biochemistry
• Cell Biology
• Orthopedics

Background:

• N-methyl-D-aspartate (NMDA) receptors are vital for osteoblast differentiation and bone function.
• Dextromethorphan (DXM), an NMDA receptor antagonist, is commonly used as an antitussive.
• The impact of DXM on osteogenesis and bone regeneration is not well understood.

Purpose of the Study:

• To investigate the effects of DXM on osteogenesis in vitro and bone regeneration in vivo.
• To evaluate DXM's influence on osteogenic marker expression and cellular activity.
• To assess DXM's impact on skeletal development and calvarial defect repair.

Main Methods:

• MC3T3-E1 preosteoblast cell line treated with DXM; assessed via RT-qPCR and Western-blot for osteogenic markers (RUNX2, OSX, OCN, Col-1α, ALP).
• Zebrafish embryos exposed to DXM; analyzed for skeletal ossification using calcein staining.
• Rat calvarial defect model used to evaluate bone regeneration with microcomputed tomography.

Main Results:

• DXM inhibited extracellular mineralization, alkaline phosphatase (ALP) activity, and osteogenic marker expression in MC3T3-E1 cells.
• DXM suppressed skeletal ossification in zebrafish and impaired bone regeneration in rats.
• No significant difference in mineral density of regenerated bone between DXM and control groups.

Conclusions:

• DXM exerts a negative influence on osteoblast function, hindering skeletal development.
• DXM impairs bone regeneration processes, as evidenced in preclinical models.
• Clinical consideration of DXM's adverse effects on bone regeneration is recommended.