Fig. 3: Sema3A secreted by DRG is involved in the effect of PEMFs on osteogenesis and adipogenesis.

a Bone marrow was collected from 20-month-old male mice that were treated with or without PEMF, and flow cytometry was performed to sort BMSCs. It was created in BioRender. Chen, S. (2025) https://BioRender.com/xi0onsj. Agreement number: FH28JKAJMF. b–d Representative images of Alizarin Red S (ARS) and Oil Red O (ORO) staining, along with quantification of ARS+ and ORO+ areas, were used to assess the levels of osteogenesis and adipogenesis. c, d n = 3 in each group from three independent experiments. e Schematic drawing of the experiment procedures. BMSCs extracted from 20-month-old mice were either cultured alone, exposed to PEMFs, co-cultured with null Sema3a or WT DRGs exposed to PEMFs, or treated with WT DRGs exposed to PEMFs in the presence of a Sema3A antagonist (1 μg/mL SM345431, United States). It was created in BioRender. Chen, S. (2025) https://BioRender.com/or7ob29. Agreement number: PX28JK9TNE. f–h Representative images of ARS and ORO staining, accompanied by quantification of ARS+ and ORO+ areas, were analyzed to assess the levels of osteogenesis and adipogenesis. g, h n = 3 in each group from three independent experiments. i–m qPCR analysis of adipogenesis- and osteogenesis-related gene expression in MSCs. n  =  3 per group from three independent experiments. Data are represented as mean ± SEM, statistical analyses were conducted with a 95% confidence interval. *P < 0.05, **P < 0.01, ***P < 0.001 by one-way ANOVA with Tukey’s multiple comparisons for c, d and g–m. P value: c P < 0.0001(ShamvsPEMFs). d P = 0.0117 (ShamvsPEMFs). g P < 0.0001 (ShamvsPEMFs+DRG). h P < 0.0001 (ShamvsPEMFs+DRG). i P < 0.0001 (ShamvsPEMFs+DRG). j P = 0.0002 (ShamvsPEMFs+DRG). k P = 0.0001 (ShamvsPEMFs+DRG). lP = 0.0223 (ShamvsPEMFs+DRG). m P = 0.0003 (ShamvsPEMFs+DRG). Source data are provided as a Source Data file.