Retinoic Acid Signal Negatively Regulates Osteo/Odontogenic Differentiation of Dental Pulp Stem Cells

Figure 2

RA inhibits osteo/odontogenic differentiation and proliferation of human DPSCs. (a) ALP activity assay results show RA inhibits ALP activities in human DPSCs after osteogenic induction for 7 days. Alizarin red staining (b) and quantitative calcium measurement (c) results show RA reduces osteogenic differentiation of human DPSCs after osteogenic induction for 14 days. Calcium nodules are observed under a microscope and displayed below (b). (d) CCK8 assays exhibit significant induction in the proliferation of DPSCs by RA after 4-day induction. Real-time RT-PCR results show RA downregulates the expressions of osteogenesis-related markers ALP (e), OPN (f), OCN (g), and transcription factor OSX (h) in human DPSCs. GAPDH is applied as the internal control. Student’s -test is performed to calculate statistical significance. All error bars mean the SD (). , , and . Scale bars represent 200 μm (b).

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