Four and a Half LIM Domain Protein 2 Enhances Differentiation and Mineralization of Human Dental Pulp Cells

• We report the effects of Four and a half LIM domain protein 2 (FHL2) overexpression on human dental pulp cells.
• FHL2 increases alkaline phosphate activity and the formation of mineralized nodules.
• FHL2 up-regulates the expression of ALP, DSP, BSP, and OPN messenger RNA and protein levels.
• FHL2 enhances the differentiation and mineralization of human dental pulp cells.

IntroductionFour and a half LIM domain protein 2 (FHL2) is 1 member of the LIM-only protein family, which is a transcriptional cofactor, playing important roles in osteoblast differentiation and bone formation. Our previous studies showed that the FHL2 protein was abundantly expressed in odontoblasts both during tooth development and in mature teeth, indicating that FHL2 might play a role in odontoblast differentiation and dentin formation. The aim of this study was to investigate the effects of FHL2 overexpression on odontoblast differentiation and mineralization of human dental pulp cells (hDPCs), exploring the function of FHL2 on dentin formation.MethodsFHL2 was steadily transfected into hDPCs. Then, alkaline phosphatase activity assay was shown; the formation of mineralized nodules was assessed by alizarin red staining; and the expression of odontoblast differentiation and mineralization-related molecules including alkaline phosphate (ALP), dentin sialoprotein (DSP), bone sialoprotein (BSP), and osteopontin (OPN) at messenger RNA and protein levels were determined by quantitative real-time polymerase chain reaction and Western blot analysis.ResultsIt was found that FHL2 overexpression could increase ALP activity and the formation of mineralized nodules of dental pulp cells. Moreover, FHL2 overexpression could up-regulate the expression of ALP, DSP, BSP, and OPN messenger RNA and protein levels significantly.ConclusionsFHL2 overexpression could enhance the differentiation and mineralization of hDPCs.