Panpan Zhang1, Yanhui Zhang2, Qing Liu3, Yunpeng Zhang4, Yawen Ji4, Xin Xu5. 1. Department of Implantology, School and Hospital of Stomatology, Shandong University, Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan 250012, China; The Center of Esthetic Dentistry, Jinan Stomatological Hospital, Jinan 250001, China. 2. Jinan Central Hospital, Jinan 250013, China. 3. Taian Maternity and Child Care Hospital, Taian 271000, China. 4. Department of Implantology, School and Hospital of Stomatology, Shandong University, Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan 250012, China. 5. Department of Implantology, School and Hospital of Stomatology, Shandong University, Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan 250012, China. Electronic address: xinxu@sdu.edu.cn.
Abstract
BACKGROUND: Periodontal ligament-associated protein-1 (PLAP-1) is a newly identified negative regulator which is the mineralization of human periodontal ligament stem cells (hPDLSCs). The aim of the present study is to determine whether 1α, 25-dihydroxyvitamin D3 (1,25(OH)2D3) could enhances the osteoblastic differentiation of hPDLSCs under inflammatory condition, and if PLAP-1 is involved in this process. MATERIALS AND METHODS: hPDLSCs were in combination or alone cultured with lipopolysaccharide (LPS) and 1,25(OH)2D3, in osteo-inductive medium. The expression levels of osteoblastic markers and PLAP-1 of hPDLCs during osteo-inductive culture were assessed by western blot and real-time quantitative PCR(qRT-PCR). The potential vitamin D receptor elements (VDREs) which were located in PLAP-1 promoter region were identified and confirmed. RESULTS: The data showed that LPS inhibited osteoblastic differentiation and induced the expression of PLAP-1 in hPDLSCs. The increasing addition of 1,25(OH)2D3 reversed the LPS-induced inhibition of osteoblastic differentiation of hPDLSCs through the suppression of PLAP-1 expression. Moreover, a potential VDRE within the PLAP-1 promoter region was identified and shown to bind with VDR by chromatin immunoprecipitation (ChIP) assays. This negative region was also found to mediate suppressor reporter gene activity. CONCLUSIONS: 1,25(OH)2D3 could enhances the osteogenic differentiation of hPDLSCs under inflammatory condition through inhibiting PLAP-1 expression transcriptionally.
BACKGROUND:Periodontal ligament-associated protein-1 (PLAP-1) is a newly identified negative regulator which is the mineralization of human periodontal ligament stem cells (hPDLSCs). The aim of the present study is to determine whether 1α, 25-dihydroxyvitamin D3 (1,25(OH)2D3) could enhances the osteoblastic differentiation of hPDLSCs under inflammatory condition, and if PLAP-1 is involved in this process. MATERIALS AND METHODS: hPDLSCs were in combination or alone cultured with lipopolysaccharide (LPS) and 1,25(OH)2D3, in osteo-inductive medium. The expression levels of osteoblastic markers and PLAP-1 of hPDLCs during osteo-inductive culture were assessed by western blot and real-time quantitative PCR(qRT-PCR). The potential vitamin D receptor elements (VDREs) which were located in PLAP-1 promoter region were identified and confirmed. RESULTS: The data showed that LPS inhibited osteoblastic differentiation and induced the expression of PLAP-1 in hPDLSCs. The increasing addition of 1,25(OH)2D3 reversed the LPS-induced inhibition of osteoblastic differentiation of hPDLSCs through the suppression of PLAP-1 expression. Moreover, a potential VDRE within the PLAP-1 promoter region was identified and shown to bind with VDR by chromatin immunoprecipitation (ChIP) assays. This negative region was also found to mediate suppressor reporter gene activity. CONCLUSIONS:1,25(OH)2D3 could enhances the osteogenic differentiation of hPDLSCs under inflammatory condition through inhibiting PLAP-1 expression transcriptionally.