Jie Liu1,2, Yuan Gao1,2, Xiaodong Zhu1,2, Yuerong Zhang1,2, Hai Xu1,3, Tianda Wang4,5,6, Guangdong Zhang7,8. 1. Jiangsu Province Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China. 2. Department of General Dentistry, The Affiliated Stomatological Hospital of Nanjing Medical University, Shang-Hai Road 1th, Nanjing, 210029, Jiangsu, China. 3. Department of Conservative Dentistry & Endodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Shang-Hai Road 1th, Nanjing, 210029, Jiangsu, China. 4. Jiangsu Province Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China. kqwangtd@gmail.com. 5. Department of General Dentistry, The Affiliated Stomatological Hospital of Nanjing Medical University, Shang-Hai Road 1th, Nanjing, 210029, Jiangsu, China. kqwangtd@gmail.com. 6. Department of General Dentistry, Boston University Henry M. Goldman School of Dental Medicine, 635 Albany Street, Boston, MA, 02118, USA. kqwangtd@gmail.com. 7. Jiangsu Province Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing, China. egd_zhang@njmu.edu.cn. 8. Department of General Dentistry, The Affiliated Stomatological Hospital of Nanjing Medical University, Shang-Hai Road 1th, Nanjing, 210029, Jiangsu, China. egd_zhang@njmu.edu.cn.
Abstract
OBJECTIVES: Polyamidoamine (PAMAM) dendrimers have well-defined structures, with monodispersity and easily modified surface groups, and they have broad applications in biomedicine. In this study, phosphorylated PAMAM (P-PAMAM) dendrimers were synthesized based on the idea of mimicking the phosphorylated proteins of dentin non-collagenous proteins (DNCP). Then, proliferation and osteo/odontogenic differentiation effects of P-PAMAM on dental pulp stem cells (DPSCs) were investigated and were compared with DNCP. MATERIALS AND METHODS: P-PAMAM was synthesized via the Mannich-type reaction. DNCP were extracted directly from human dentin with ethylenediaminetetraacetic acid (EDTA) solution. Then, the conditioned medium of P-PAMAM and DNCP were prepared respectively and applied to DPSCs. Proliferation of P-PAMAM was investigated with CCK-8, flow cytometry, and EdU test. Osteo/odontogenic differentiation of P-PAMAM was analyzed using alkaline phosphatase activity and staining, RT-PCR, western blot, alizarin red staining, and immunofluorescence staining. RESULTS: Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance revealed that PAMAM were successfully phosphorylated. Western blot verified that the extracted DNCP contained dentin-related proteins DSPP, OPN, and BMP2. In cell proliferation, there was no apparent difference between P-PAMAM, DNCP, and Control groups (P > 0.05). P-PAMAM and DNCP upregulated related genes and proteins expression (DSPP/DSPP, COL-1/COL-1, ALP/ALP, RUNX2/RUNX2, OSX/OSX, OCN/OCN) and matrix mineralization. Still, the potential was lower than that of DNCP (P < 0.05). CONCLUSIONS: P-PAMAM dendrimers, as a biomimetic analog of DNCP, promote osteo/odontogenic differentiation of DPSCs without influencing their proliferation at a low concentration. CLINICAL RELEVANCE: This preliminary study about P-PAMAM dendrimers is expected to provide a more convenient bioactive macromolecular material for the regeneration of the pulp-dentin complex.
OBJECTIVES: Polyamidoamine (PAMAM) dendrimers have well-defined structures, with monodispersity and easily modified surface groups, and they have broad applications in biomedicine. In this study, phosphorylated PAMAM (P-PAMAM) dendrimers were synthesized based on the idea of mimicking the phosphorylated proteins of dentin non-collagenous proteins (DNCP). Then, proliferation and osteo/odontogenic differentiation effects of P-PAMAM on dental pulp stem cells (DPSCs) were investigated and were compared with DNCP. MATERIALS AND METHODS: P-PAMAM was synthesized via the Mannich-type reaction. DNCP were extracted directly from human dentin with ethylenediaminetetraacetic acid (EDTA) solution. Then, the conditioned medium of P-PAMAM and DNCP were prepared respectively and applied to DPSCs. Proliferation of P-PAMAM was investigated with CCK-8, flow cytometry, and EdU test. Osteo/odontogenic differentiation of P-PAMAM was analyzed using alkaline phosphatase activity and staining, RT-PCR, western blot, alizarin red staining, and immunofluorescence staining. RESULTS: Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance revealed that PAMAM were successfully phosphorylated. Western blot verified that the extracted DNCP contained dentin-related proteins DSPP, OPN, and BMP2. In cell proliferation, there was no apparent difference between P-PAMAM, DNCP, and Control groups (P > 0.05). P-PAMAM and DNCP upregulated related genes and proteins expression (DSPP/DSPP, COL-1/COL-1, ALP/ALP, RUNX2/RUNX2, OSX/OSX, OCN/OCN) and matrix mineralization. Still, the potential was lower than that of DNCP (P < 0.05). CONCLUSIONS: P-PAMAM dendrimers, as a biomimetic analog of DNCP, promote osteo/odontogenic differentiation of DPSCs without influencing their proliferation at a low concentration. CLINICAL RELEVANCE: This preliminary study about P-PAMAM dendrimers is expected to provide a more convenient bioactive macromolecular material for the regeneration of the pulp-dentin complex.
Authors: S Gronthos; J Brahim; W Li; L W Fisher; N Cherman; A Boyde; P DenBesten; P Gehron Robey; S Shi Journal: J Dent Res Date: 2002-08 Impact factor: 6.116