Conclusion
In summary, TRPC6 activation in PDLSCs mediated by appropriate mechanical force application contributes to periodontal tissue reconstruction. PDLSCs modulate periodontal tissue remodeling under appropriate mechanical stimulation through TRPC6; however, under excessive stress, alveolar bone and tooth roots are readily absorbed. Under this condition, environmental factors play a leading role, and the regulatory effect of TRPC6 is not obvious.
Methods
Human PDLSCs (hPDLSCs) were analyzed in the presence or absence of force loading with the Flexcell loading system in vitro. Then, periodontal tissues were analyzed after mechanical stimulation in vivo. In addition, cells in a confined microenvironment were analyzed to observe changes in the cytoskeleton and migration. Finally, TRPC6-/- mice were used to further verify the effect of TRPC6. After force application, the OTM distance, bone marrow density (BMD), TRPC6 and COL1 expression, and TRAP staining were evaluated in periodontal tissues.
Results
RNA sequencing (RNA-seq) and western blot analyses revealed that TRPC6 was important during mechanical force application to hPDLSCs. Appropriate mechanical force application also induced TRPC6 activation in the OTM model and the confined microenvironment. Under a slightly confined microenvironment, treatment with the TRPC6 inhibitor SKF96365 and TRPC6 knockout decreased the migration speed of hPDLSCs and mouse bone marrow mesenchymal stem cells (mBMSCs). In addition, TRPC6-/- mice showed lower OTM distances and reduced osteogenic and osteoclastic differentiation.