Galectin-3 Plays an Important Role in BMP7-Induced Cementoblastic Differentiation of Human Periodontal Ligament Cells by Interacting with Extracellular Components

Figure 7

Treatment with GB1107, a galectin-3-specific inhibitor, inhibits BMP7-induced cementoblastic differentiation. (a) hPDLCs were treated with the indicated concentrations of GB1107 for up to 72 hours. Cells were collected at the indicated time, and the proliferation assay was performed to assess the cells’ viability, as indicated in Materials and Methods. (b) Downregulation of BMP7-Smad1 signaling via treatment with GB1107. The amounts of the indicated proteins and the relative values of p-Smad1 to Smad1 are shown in (A) and (B). In (A), lane 1, undifferentiated hPDLCs; lane 2, hPDLCs treated with 100 ng/mL BMP7 and 10 μM SB431542 for 72 hours; lane 3, hPDLCs treated with BMP7, SB431542, and 15 μM GB1107 for 72 hours. In (B), the quantification of the intensity of each band on immunoblots and the calculation of relative values of p-Smad1 (indicated by arrowhead) to Smad1 were analyzed using ImageJ program [60]. (c) GB1107 inhibited BMP7-induced cementoblastic differentiation. When 15 μM GB1107 was continuously treated during the 9-day differentiation period, the amount of endogenous galectin-3 (A) and cell morphologies (B) were not affected. In (A), lane 1, undifferentiated hPDLCs; lane 2, hPDLCs treated with 100 ng/mL BMP7 and 10 μM SB431542 for 9 days; lane 3, hPDLCs treated with BMP7, SB431542, and 15 μM GB1107 for 9 days. Transcriptional expression of the representative cementoblastic markers is shown in (C). . Statistical analysis was performed using Student’s -test (). (d) Inhibition of galectin-3 downregulated mineralization efficiency of human cementoblast-like cells. After 14-day incubation in media containing mineralization additives, degree of mineralization was detected using alizarin red S staining (A) and was quantified via optical density at 405 nm (B). ; . Statistical analysis was performed using Students -test ().

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