Wang Jiafeng, Qu Xiaozhang, Zhang Zhimin, Meng Xiuping, Qi Guohua
Department of Endodontics, Hospital of Stomatology, Jilin University, Changchun 130021 Jilin, P. R. China.
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 Jilin, P. R. China.
ACS Meas Sci Au. 2025 Mar 12;5(3):294-303. doi: 10.1021/acsmeasuresciau.5c00005. eCollection 2025 Jun 18.
Stem cells are a class of multipotential cells with the capability of self-replication, which can differentiate into multiple functional cells under extra stimulus. The differentiation of stem cells has important implications for tissue regeneration. Therefore, controllable regulation of dental pulp stem cell (DPSC) behaviors is critical for repairment and regeneration of damaged teeth tissues. Rapid promotion of DPSCs, directed differentiation, and revealing molecular events within the organelle level during the cell differentiation process are in great demand for regeneration of teeth, which remains a great challenge. Herein, we developed a highly effective and uncomplicated stimulation platform to promote the DPSCs for odontogenic differentiation based on impulse electrical stimulation and revealed the molecular stress response of mitochondria during cell differentiation based on fluorescence imaging combined with surface-enhanced Raman spectroscopy (SERS). Our approach can greatly shorten the DPSC differentiation time from usually more than 20 days to only about 3 days under 0.8 V for 5 min every day than drug stimulation. Notably, the glycogen and adenosine triphosphate levels within mitochondria were apparently elevated, which is conducive to improving the progression of cell differentiation. Simultaneously, the expression of mitofusin1 and mitofusin2 within mitochondria was significantly down-regulated during the differentiation process. Mechanistically, the molecular insights into mitochondria within DPSCs were clearly revealed through SERS spectra. It demonstrated that the expression of phenylalanine was significantly reduced, whereas the contents of tryptophan within mitochondria were promoted during the cell differentiation process. This study provides a comprehensive and clinically feasible strategy for the rapid promotion of DPSCs-directed differentiation and reveals the molecular dynamic changes within mitochondria, which broadens the biomedical cognition of electrical stimulation for dental pulp stem cell differentiation and provides a potential application for teeth tissue regeneration in the future.
干细胞是一类具有自我复制能力的多能细胞，在额外刺激下可分化为多种功能细胞。干细胞的分化对组织再生具有重要意义。因此，可控调节牙髓干细胞（DPSC）的行为对于受损牙齿组织的修复和再生至关重要。快速促进DPSC定向分化，并揭示细胞分化过程中细胞器水平内的分子事件，对牙齿再生的需求很大，这仍然是一个巨大的挑战。在此，我们基于脉冲电刺激开发了一个高效且简单的刺激平台，以促进DPSC向牙源性分化，并基于荧光成像结合表面增强拉曼光谱（SERS）揭示了细胞分化过程中线粒体的分子应激反应。我们的方法可以将DPSC分化时间从通常超过20天大大缩短至每天在0.8V下刺激5分钟时仅约3天，相比药物刺激。值得注意的是，线粒体内的糖原和三磷酸腺苷水平明显升高，这有利于改善细胞分化进程。同时，分化过程中线粒体内的线粒体融合蛋白1和线粒体融合蛋白2的表达显著下调。从机制上讲，通过SERS光谱清楚地揭示了DPSC中线粒体的分子见解。结果表明，在细胞分化过程中，苯丙氨酸的表达显著降低，而线粒体内色氨酸的含量增加。本研究为快速促进DPSC定向分化提供了一种全面且临床可行的策略，并揭示了线粒体内的分子动态变化，拓宽了电刺激对牙髓干细胞分化的生物医学认知，并为未来牙齿组织再生提供了潜在应用。
