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.
Department of Oral Anatomy and Physiology, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China.
Arch Oral Biol. 2017 Nov;83:33-39. doi: 10.1016/j.archoralbio.2017.06.034. Epub 2017 Jun 30.
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.
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.
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.
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.
褪黑素对人牙髓细胞（hDPC）增殖和分化的影响尚不清楚。本研究旨在探讨褪黑素对 hDPC 增殖和分化的影响。
从 18 至 25 岁志愿者的第三磨牙中获得原代 hDPC。CCK8 法在第 1、2、3、4、5 天评估褪黑素对细胞增殖的影响。在 7 天的成骨诱导后，用商业试剂盒测量碱性磷酸酶（ALP）活性。然后通过免疫细胞化学染色和 Western blot 分析测定牙本质涎磷蛋白（DSPP）的水平，随后进行定量实时逆转录-聚合酶链反应（qRT-PCR）分析 ALP 和 DSPP 的 mRNA 水平。最后，将暴露于含褪黑素或载体的成骨培养基中的 hDPC 培养 14 天，用茜素红染色检测矿化结节的形成。
褪黑素以浓度和时间依赖的方式显著抑制 hDPC 的增殖能力。在含有褪黑素的成骨诱导培养基中培养的 hDPC 呈现 ALP 活性增加、DSPP 表达、ALP 和 DSPP 的 mRNA 水平增加以及矿化结节形成。
这些发现表明，生理浓度的褪黑素可以抑制 hDPC 的增殖并促进其分化，这可能为调节 DPC 以实现牙本质再生的机制提供一些新的见解。
