Abstract

Aim

To determine whether irisin, a newly discovered myokine that links exercise-induced and metabolic homeostasis, is able to promote odontogenic differentiation and angiogenesis in human dental pulp cells (HDPCs).

Methodology

Cell viability in the presence of irisin was measured. Real-time PCR and Western blot analysis were performed to evaluate the expression levels of irisin, odontogenic and angiogenic markers. The involvement of mitogen-activated protein kinase (MAPK) and the protein kinase B (Akt) signalling pathway was evaluated by Western blot. To evaluate mineralization nodule formation, alkaline phosphatase (ALP) staining and alizarin red S staining were performed. Scratch wound assays were performed to evaluate the effects of irisin on cell migration. The data were analysed using one-way analysis of variance (anova) followed by Tukey post hoc test and Student’s t-test. Statistical significance was considered at P < 0.05.

Results

Irisin significantly promoted odontogenic differentiation as evidenced by formation of mineralized nodules, induction of ALP activity and upregulation of odontogenic and angiogenic markers (P < 0.05). Scratch wound assays revealed that irisin significantly increased migration of HDPCs (P < 0.05). Phosphorylation of both MAPK and Akt was increased by irisin. MAPK and Akt inhibitors inhibited mineralization, cell migration and the increased expression of odontogenic and angiogenic markers.

Conclusions

Irisin promoted odontogenic differentiation and mineralization and has the potential for angiogenesis through activation of the MAPK and Akt signalling pathways in HDPCs.