The effect of matrix extracellular phosphoglycoprotein and its downstream osteogenesis-related gene expression on the proliferation and differentiation of human dental pulp cells

Introduction: Matrix extracellular phosphoglycoprotein (MEPE), a new member of the small Integrin binding ligand N-glycosylated (SIBLING) family, is believed to play multifunctional roles in regulation of cell signaling, mineral homeostasis, and mineralization.

Methods: To study how MEPE affects the downstream genes involved in regulation of the proliferation and osteogenesis differentiation of dental pulp cells (DPCs), we explored the proliferation and osteogenesis differentiation capability of DPCs stimulated with recombinant MEPE or transfected with adenoviral-mediated human MEPE gene and used a systematic approach by osteogenesis real-time polymerase chain reaction arrays to profile osteogenesis-related gene expression after MEPE gene transfection.

Results: Our results indicated higher proliferation capability in a time- and dose-dependent pattern by cholecystokinin octapeptide assay, and gene/protein expression of osteogenic markers bone sialoprotein, dentin sialophosphoprotein, osteocalcin, and collagen I were up-regulated dependent on time points showed by real-time polymerase chain reaction and Western blot. Moreover, a total of 3 genes, including enamelin, transforming growth factor-β2, and Integrin α2, were significantly up-regulated.

Conclusions: These results indicated that MEPE appeared to play an important positive role in proliferation and osteogenesis differentiation of DPCs through interaction with downstream signals.