Abstract: Objective: To investigate the effects of different concentrations of magnesium ions (Mg²⁺) on the biological behavior of human maxillary sinus membrane stem cells (hMSMSCs). Methods: hMSMSCs were extracted in vitro, and flow cytometry and multilineage differentiation experiments were conducted to identify their mesenchymal stem cell characteristics. Subsequently, the cells were cultured at concentrations of 0.8 mmol/L, 1.8 mmol/L, 2.8 mmol/L, and 5.8 mmol/L of Mg²⁺. Cell adhesion and proliferation of hMSMSCs were evaluated using CCK-8 assay and Calcein AM/PI staining, while cell adhesion extension was assessed using Rhodamine phalloidin-DAPI staining. ALP activity, ALP staining, and Alizarin Red staining were performed on hMSMSCs after osteogenic induction culture, and qRT-PCR experiments were conducted to detect the expression differences of osteogenic-related growth factors. Results: Optimal concentration of Mg²⁺ effectively improved cell adhesion, extension, and proliferation of hMSMSCs. 1.8 mmol/L Mg²⁺ enhanced ALP activity in hMSMSCs, significantly improved extracellular calcium nodule formation, and upregulated the expression of osteogenic-related genes. Conversely, excessively high Mg²⁺ concentrations inhibited osteogenic differentiation of hMSMSCs (P＜0.05). Conclusion: Appropriate concentration of Mg²⁺ (1.8 mmol/L) promotes cell spreading and adhesion of hMSMSCs, facilitating proliferation and osteogenic differentiation.

Key words: mesenchymal stem cell, osteogenesis, maxillary sinus, magnesium ion