Physical factors promote osteogenic differentiation of stem cells

BACKGROUND: In response to the limitations of traditional repair methods for bone defects, stem cells are widely used in the research of regenerative medicine. Chemical factors are the current research hotspots, but recent studies confirm that the application of physical factors to regulate stem cell differentiation at home and abroad has been intensifying, and physical factors combined with biological scaffolds in bone tissue engineering provide a new idea and method for solving the difficult problem of bone defect repair, with good development prospects. OBJECTIVE: To summarize the molecular mechanisms of physical factors such as electromagnetic fields and ultrasound on osteogenic differentiation of stem cells as well as the regulation of signaling pathways and the feasibility of their application in bone tissue engineering. METHODS: A computerized search of the CNKI and PubMed for the last 20 years was conducted. In the title and abstract, we used “stem cell, bone defect, osteogenic differentiation, electromagnetic fields, ultrasound, shock wave, low-level laser therapy, mechanical force, bone tissue engineering” in Chinese and “stem cell, osteoporosis, osteogenic differentiation, electromagnetic fields, ultrasound, bone tissue engineering” in English as search terms. A total of 94 relevant articles were included for review. RESULTS AND CONCLUSION: (1) As a non-invasive, non-contact adjuvant therapy, physical factors have a significant impact on bone tissue engineering, and have a positive effect on regulating osteogenic differentiation of stem cells, promoting cell proliferation and viability in bone engineering scaffolds. (2) In addition to activating signaling pathways and osteogenic gene transcription, physical factors can also improve vascularization, increase the volume, area and thickness of bone formed in the stent, promote osseointegration, and improve the success rate of bone scaffolds in regenerating healthy bone tissue. (3) However, the use of physical factors for bone tissue engineering uses different experimental conditions, such as scaffold type, cell type, and intervention conditions, and cannot be directly compared to determine the best parameter settings. There is also a lack of consistency in the effectiveness of these different interventions in promoting fracture healing in clinical use. Therefore, it is necessary to further determine the optimal parameters of physical factors for bone tissue engineering in the future. (4) In general, as an ideal adjuvant therapy, physical factors have great potential in combining with various biomaterials and applying them in bone tissue engineering.