Journal: Bone Research

Article Title: SphK1/mitophagy axis in cementocytes drives orthodontic root resorption via mitochondrial transfer to osteoclasts

doi: 10.1038/s41413-026-00538-0

Figure Lengend Snippet: SphK1 inhibition reduces osteoclastic glycolysis and activity as well as cementocyte mitophagy and OIIRR in vivo. a The protein expression of c-Fos, NFATc1, Ctsk and OSCAR in BMMs were examined by western blot analysis using GAPDH as a loading control. Quantitative RT-PCR analysis was performed to examine the mRNA levels of c-Fos , Nfatc1 , Ctsk and Oscar . b The protein expression of GLUT1, GLUT3, LDHA and PKM2 in BMMs were examined by western blot analysis using β-actin as a loading control. Quantitative RT-PCR analysis was performed to examine the mRNA levels of Slc2a1 , Slc2a3 , Ldha and Pkm . c , d Representative HE and Masson’s trichrome staining images of the distobuccal roots of M1 under 100 g orthodontic force at Day 7 and Day 14. PF-543 was adopted to selectively inhibited the expression of SphK1. The black arrow indicated the resorption pits. Scale bar = 250 μm. e , f Representative immunohistochemical images of PARKIN and DRP1 at the mesial surface of distobuccal roots. The red box indicated the interested area at the lower panel. The black arrow indicated the positive cells at the interested area. Scale bar = 25 μm. g , h Representative immunofluorescence images of GLUT1 or LDHA (red) at the mesial surface of distobuccal roots. The Ctsk (green) was used to label osteoclasts. The yellow box indicated the interested area at the lower panel. The white arrow indicated the osteoclasts at the interested area. R, Root; PDL, Periodontal ligament; AB, Alveolar bone. Scale bar = 25 μm. i , j Semi-quantitative analysis of PARKIN and DRP1 positive staining, as well as GLUT1- and LDHA-positive cells, at the interested area. Statistical comparison was performed using two-tailed Student’s t test or one-way ANOVA with Tukey’s post hoc test. P < 0.05 was considered statistically significant. n = 5 for each group. All data were presented as mean ± SEM

Article Snippet: After blocking with 5% BSA, the membranes were incubated overnight at 4 °C with the following primary antibodies: PINK1 (1:1 000, Proteintech 23274-1-AP), PARKIN (1:1 000, Proteintech 14060-1-AP), DRP1 (1:2 000, Proteintech 12957-1-AP), FIS1 (1:2 000, Proteintech 10956-1-AP), c-Fos (1:1 000, CST 31254T), NFATc1 (1:1 000, ABclonal A1539), Ctsk (1:1 000, Proteintech 11239-1-AP), OSCAR (1:1 000, Huabio ER61888), GLUT1 (1:1 000, Proteintech 21829-1-AP), GLUT3 (1:3 000, Proteintech 20403-1-AP), LDHA (1:1 000, ABclonal A1146), PKM2 (1:1 000, ABclonal A20991).

Techniques: Inhibition, Activity Assay, In Vivo, Expressing, Western Blot, Control, Quantitative RT-PCR, Staining, Immunohistochemical staining, Immunofluorescence, Comparison, Two Tailed Test