Hou Huailong, Qiu Zhengjun, Che Jingyi, Li Yanping, Sun Jingxuan, Zhang Weiwei, Ma Jinjie, Zhang Shuang, Li Mengdi, Niu Yumei, He Lina
Department of Endodontics, The First Affiliated Hospital of Harbin Medical University, 143 Yiman Street, St Nangang Dist., Harbin, 150001, China.
J Mol Histol. 2025 Feb 26;56(2):97. doi: 10.1007/s10735-025-10377-8.
Dental pulp stem cells (DPSCs), a subset of tooth-derived mesenchymal stem cells (MSCs), demonstrate significant promise in clinical stem cell therapy. However, prolonged in vitro expansion commonly results in compromised stemness, limiting therapeutic efficacy. Thus, maintaining the stemness of DPSCs during expansion and culture is a key challenge for regenerative medicine. In the current study, the impact of simulated microgravity (SMG) on DPSC stemness was investigated using the three-dimensional clinostat Cellspace-3D. After SMG treatment for 3 days, DPSCs demonstrated markedly enhanced replicative activity, proliferation efficiency, self-renewal capacity, and effective inhibition of the senescence process. Under specific differentiation induction conditions, DPSCs in the SMG group exhibited superior osteogenic, adipogenic, chondrogenic, and neural differentiation potentials. Additionally, DPSCs exhibited higher expression levels of the MSC surface markers Stro-1 and CD146 and stemness maintenance-related genes Oct4, Nanog, and Sox2 in the SMG group compared to those from the normal gravity (NG) group. To elucidate the potential molecular mechanisms by which SMG influences the stemness of DPSCs, transcriptome sequencing of total RNA was performed, and identified that differentially expressed genes (DEGs) are closely associated with the MAPK signaling pathway. Further verification experiments demonstrated that the MAPK/ERK signaling pathway was activated in the SMG group. In conclusion, SMG effectively maintains the stemness of DPSCs cultivated in vitro, and its mechanism of action may be associated with the activation of the MAPK/ERK signaling pathway.
牙髓干细胞（DPSCs）是牙齿来源的间充质干细胞（MSCs）的一个亚群，在临床干细胞治疗中显示出巨大的前景。然而，长时间的体外扩增通常会导致干性受损，从而限制治疗效果。因此，在扩增和培养过程中维持DPSCs的干性是再生医学面临的一项关键挑战。在本研究中，使用三维回转器Cellspace-3D研究了模拟微重力（SMG）对DPSC干性的影响。经过3天的SMG处理后，DPSCs表现出明显增强的复制活性、增殖效率、自我更新能力以及对衰老过程的有效抑制。在特定的分化诱导条件下，SMG组的DPSCs表现出更强的成骨、成脂、成软骨和神经分化潜能。此外，与正常重力（NG）组相比，SMG组的DPSCs在MSC表面标志物Stro-1和CD146以及干性维持相关基因Oct4、Nanog和Sox2的表达水平更高。为了阐明SMG影响DPSCs干性的潜在分子机制，对总RNA进行了转录组测序，并确定差异表达基因（DEGs）与MAPK信号通路密切相关。进一步的验证实验表明，SMG组中MAPK/ERK信号通路被激活。总之，SMG有效地维持了体外培养的DPSCs的干性，其作用机制可能与MAPK/ERK信号通路的激活有关。
