Cav1.2 regulated odontogenic differentiation of NG2+ pericytes during pulp injury

NG2(+) pericytes, as the possible precursor cells of mesenchymal stem cells (MSCs), have drawn attention due to their ability to differentiate into odontoblasts. Ca(v)1.2 is involved in the differentiation process of stem cells, but its role in the differentiation of NG2(+) pericytes is not clear. The aim of the present study was to examine the role of Ca(v)1.2 in the differentiation of NG2(+) pericytes into odontoblasts. NG2(+) pericytes were obtained from human dental pulp cells by magnetic-activated cell sorting. During the odontogenic differentiation of NG2(+) pericytes, the effects of the Ca(v)1.2 inhibitors, nimodipine and Ca(v)1.2 knockdown shRNA, were analyzed by real-time polymerase chain reaction and alizarin red staining. NG2CreERT2/Rosa26-GFP lineage-tracing mice were established to further investigate the roles of NG2(+) pericytes and Ca(v)1.2 in incisor self-repair after injury in vivo. At 10 min, 1 day, and 3 days after pulp injuries in transgenic mice, NG2-GFP(+) and Ca(v)1.2 immunofluorescence co-staining was performed on the incisors. Nimodipine treatment and Ca(v)1.2 knockdown showed similar inhibition of calcium nodule formation and mRNA levels of osteogenic markers (DSPP, DMP1, and Runx2, p < 0.05). NG2(+) pericytes migrated from their inherent perivascular location to the odontoblast layers after pulp injury. Ca(v)1.2 showed a similar response pattern as NG2(+) pericytes and gradually returned to normal levels. In addition, many co-stained areas of Ca(v)1.2 and NG2(+) pericytes, both near the perivascular and odontoblast layers, were observed. These results indicate that Ca(v)1.2 played a vital role in the odontogenic differentiation of NG2(+) pericytes, and that it might be closely linked to the NG2(+) pericytes-mediated repair of dental pulp injury in vivo.

Automated summary

NG2(+) pericytes have the ability to differentiate into odontoblasts, and Ca(v)1.2 plays a vital role in this differentiation process.