Effects of cannabidiol on biomineralization and inflammatory mediators expression in immortalized murine dental pulp cells and macrophages under pro-inflammatory conditions

Objectives

This study investigated the in vitro effects of cannabidiol (CBD) on dental pulp cells and macrophages under pro-inflammatory conditions.

Materials and Methods

Mouse dental pulp cells (OD-21) were pre-stimulated with tumor necrosis factor alpha (10 ng/mL) or left untreated, then exposed to CBD at concentrations of 0.01 µM, 0.1 µM, 1 µM, and 10 µM for 24 h and 7 days. Cell viability was assessed using the MTT assay, while gene expression related to mineralization—Dentin Sialophosphoprotein (Dspp), Dentin Matrix Protein 1 (Dmp1), Runt-related transcription factor 2 (Runx2), TNF-α (Tnf), and prostaglandin-endoperoxide synthase 2 (Ptgs2) were analyzed via quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Mineralization nodule formation was evaluated using alizarin red staining. Macrophages (RAW 264.7) were stimulated with lipopolysaccharide (LPS) for 2 h before exposure to the same CBD concentrations. Data analysis included the Shapiro-Wilk normality test and comparisons using ANOVA and Tukey's post-hoc test (α = 0.05).

Results

The findings indicated that CBD did not significantly affect OD-21 cell viability, except for the 10 µM concentration after 7 days (p < 0.05). CBD treatment promoted mineralization, with significant differences observed among groups (p < 0.05). Notably, Ptgs2 expression varied between time points, while Runx2 expression was significantly reduced at 24 h (p < 0.05). In macrophages, Ptgs2 and Tnf levels were downregulated by all tested CBD concentrations (p < 0.05).

Conclusion

These results indicate that cannabidiol positively influence the biomineralization process and modulate inflammatory mediator expression.

Clinical relevance

Our research indicates that cannabidiol presents biomineralization potential within inflammatory contexts, implying its potential as a promisor bioactive substance for regenerating oral tissues by interacting with cells and tissues to induce specific responses.