Conclusions
MAPK pathway involved in PHT-regulated migration and osteogenic differentiation in human PDL cells.
Methods
Human PDL cells were cultured and identified. 20-100 μg/mL PHT were used in our study. The proliferation of PDL cells was determined by the EdU assay. A wound healing assay was used to detect cell migration. Matrix metalloproteinase (MMP)-1, MMP-2, tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 expression were analyzed by real time-PCR. The protein expression of MMP-1 and phosphorylated mitogen-activated protein kinases (MAPKs) were detected by western blotting assay. Osteogenic differentiation was assessed by alkaline phosphatase (ALP) staining.
Results
We found that 20-100 μg/mL of PHT did not affect PDL cells proliferation, whereas 50-100 μg/mL of PHT inhibited cell migration. The 50 or 100 μg/mL of PHT decreased the gene and protein expression of MMP-1, but increased the gene expression of TIMP-1. MMP-2 and TIMP-2 were not affected by 20-100 μg/mL of PHT. Further, 20-50 μg/mL of PHT increased ALP expression, but 100 μg/mL of PHT depressed ALP expression. The extracellular regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 were activated by PHT. JNK and ERK are involved in PHT-regulated migration. JNK plays an essential role in PHT-induced osteogenic differentiation. Conclusions: MAPK pathway involved in PHT-regulated migration and osteogenic differentiation in human PDL cells.