Qin Liu1, Wenguo Fan2, Yifan He3, Fuping Zhang2, Xiaoyan Guan1, Qianyi Deng1, Xianjun Lu4, Hongwen He5, Fang Huang6. 1. Department of Pediatric Dentistry, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China. 2. Department of Oral Anatomy and Physiology, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China. 3. Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China; Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China. 4. Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China. 5. Department of Oral Anatomy and Physiology, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China. Electronic address: hehw@mail.sysu.edu.cn. 6. Department of Pediatric Dentistry, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China. Electronic address: hfang@mail.sysu.edu.cn.
Abstract
OBJECTIVE: Effects of melatonin on the proliferation and differentiation of human dental pulp cells (hDPCs) remain unclear. The purpose of this study was to investigate the effect of melatonin on the proliferation and differentiation of the hDPCs. DESIGN: Primary hDPCs were obtained from the third molar of volunteer aged from 18 to 25. CCK8 assay evaluated the effect of melatonin upon cell proliferation at day 1, 2, 3, 4, 5. After 7days' osteogenic induction with melatonin or vehicle, alkaline phosphatase (ALP) activity was measured with a commercial kit. Then levels of dentin sialophosphoprotein (DSPP) were determined by immunocytochemical staining and western blot analysis, followed by quantitative real-time reverse transcription-Polymerase chain reaction (qRT-PCR) to analyse mRNA levels of ALP and DSPP. Finally hDPCs exposed to osteogenic medium containing melatonin or vehicle for 14days were stained with alizarin red to detect mineralization nodules formation. RESULTS: Melatonin significantly inhibited the proliferative ability of the hDPCs in a concentration- and time-dependent manner. The hDPCs cultured in osteogenic induction medium with melatonin presented an increase of ALP activity, expression of DSPP, mRNA levels of ALP and DSPP, and mineralization nodules formation. CONCLUSIONS: These findings indicate that melatonin at physiological concentrations can inhibit proliferation and promote the differentiation of hDPCs, which might give some new insights into the mechanism of regulating DPCs to achieve dentine regeneration.
OBJECTIVE: Effects of melatonin on the proliferation and differentiation of human dental pulp cells (hDPCs) remain unclear. The purpose of this study was to investigate the effect of melatonin on the proliferation and differentiation of the hDPCs. DESIGN: Primary hDPCs were obtained from the third molar of volunteer aged from 18 to 25. CCK8 assay evaluated the effect of melatonin upon cell proliferation at day 1, 2, 3, 4, 5. After 7days' osteogenic induction with melatonin or vehicle, alkaline phosphatase (ALP) activity was measured with a commercial kit. Then levels of dentin sialophosphoprotein (DSPP) were determined by immunocytochemical staining and western blot analysis, followed by quantitative real-time reverse transcription-Polymerase chain reaction (qRT-PCR) to analyse mRNA levels of ALP and DSPP. Finally hDPCs exposed to osteogenic medium containing melatonin or vehicle for 14days were stained with alizarin red to detect mineralization nodules formation. RESULTS:Melatonin significantly inhibited the proliferative ability of the hDPCs in a concentration- and time-dependent manner. The hDPCs cultured in osteogenic induction medium with melatonin presented an increase of ALP activity, expression of DSPP, mRNA levels of ALP and DSPP, and mineralization nodules formation. CONCLUSIONS: These findings indicate that melatonin at physiological concentrations can inhibit proliferation and promote the differentiation of hDPCs, which might give some new insights into the mechanism of regulating DPCs to achieve dentine regeneration.