Investigation on the Oxytocin Effect on Proliferation and Osteogenic/Odontogenic Differentiation of Human Stem Cells from the Apical Papilla: An in vitro study

Abstract Objective This experimental study was conducted with the aim of investigating the effect of oxytocin (OT) on the proliferation and osteo/odontogenic differentiation of human stem cells from the apical papilla (hSCAPs). Material and Methods hSCAPs were isolated from the apical papilla of the incomplete root of human third molar. MTT assay was performed in three concentrations of 25, 50 and 100 nM OT at 24, 48 and 72 hours to evaluate cell viability and proliferation. 100 nM OT was given to the experimental groups in osteogenic environment. Osteogenic differentiation of hSCAPs was evaluated using alizarin red staining, ALP activity and qPCR on days 7, 14 and 21. The ANOVA analysis, Tukey’s test, and t-test was implemented to analyze the data (α = 0.05). Results After 24 hours all there concentrations (25,50and 100nM) and after 48 and 72 hours only 100 nM concentration of OT had a significant positive effect on the survival/proliferation rate of hSCAPs (P < 0.001). Alizarin red staining evaluation showed successful differentiation of the cells of all groups. Quantitative analysis of the staining revealed treatment with OT increased the osteogenic differentiation of hSCAPs. Molecular analysis by qPCR showed increased expression of osteogenic genes, including ALP , COL1A1 and RUNX2 , and as well as odontogenic genes, including DSPP , and DMP1 . And also, ALP activity of the cells under OT treatment, at all three time points was higher than the control group. Conclusion The results of the present study showed that OT has a positive effect on the proliferation and osteo/odentogenic differentiation of hSCAPs. It suggested, the potential application of OT in regenerative endodontics.