Abstract: Objective: To study the effect and mechanism of SIRT1 on osteogenic differentiation of PDLSCs stimulated by orthodontic static pressure. Methods: Primary PDLSCs were cultured and the third generation of PDLSCs was divided into control group, orthodontic static pressure group, orthodontic static pressure+resveratrol group, and orthodontic static pressure+nicotinamide group. The expression of SIRT1, OCN, Runx2, acetylated NF-κB, FOXO1, acetylated FOXO1, and the contents of TNF-α, IL-6, and MCP-1 were measured. The mineralized nodules numbers of alizarin red staining after osteogenesis induction were detected. Results: Compared with the control group, the number of mineralized nodules and the expression of SIRT1, OCN, Runx2, and FOXO1 increased, the expression of acetylated NF-κB, acetylated FOXO1, and the contents of TNF-α, IL-6, and MCP-1 decreased in orthodontic static pressure group. Compared with orthodontic static pressure group, the number of mineralized nodules and the expression of SIRT1, OCN, Runx2, and FOXO1 increased; the expression of acetylated NF-κB, acetylated FOXO1, and the contents of TNF-α, IL-6, and MCP-1 decreased in orthodontic static pressure+resveratrol group; the number of mineralized nodules and the expression of SIRT1, OCN, Runx2, and FOXO1 decreased; the expression of acetylated NF-κB, acetylated FOXO1, and the contents of TNF-α, IL-6, and MCP-1 increased in orthodontic static pressure+nicotinamide group. Conclusion: SIRT1 plays an important role in the osteogenic differentiation of PDLSCs under the stimulation of orthodontic static pressure, and its possible molecular mechanism is to regulate the acetylation of NF-κB and FoxO1.

Key words: periodontal ligament stem cells, silent information regulator 1, osteogenic differentiation, acetylation