Melatonin attenuates dental pulp stem cells senescence due to vitro expansion via inhibiting MMP3

Abstract Objective We aimed to identify the crucial genes involved in dental pulp stem cell (DPSC) senescence and evaluate the impact of melatonin on DPSC senescence. Methods Western blotting, SA‐β‐Gal staining and ALP staining were used to evaluate the senescence and differentiation potential of DPSCs. The optimal concentration of melatonin was determined using the CCK‐8 assay. Differentially expressed genes (DEGs) involved in DPSC senescence were obtained via bioinformatics analysis, followed by RT–qPCR. Gain‐ and loss‐of‐function studies were conducted to explore the role of MMP3 in DPSC in vitro expansion and in response to melatonin. GSEA was employed to analyse MMP3‐related pathways in cellular senescence. Results Treatment with 0.1 μM melatonin attenuated cellular senescence and differentiation potential suppression in DPSCs due to long‐term in vitro expansion. MMP3 was a crucial gene in senescence, as confirmed by bioinformatics analysis, RT–qPCR and Western blotting. Furthermore, gain‐ and loss‐of‐function studies revealed that MMP3 played a regulatory role in cellular senescence. Rescue assays showed that overexpression of MMP3 reversed the effect of melatonin on senescence. GSEA revealed that the MMP3‐dependent anti‐senescence effect of melatonin was associated with the IL6‐JAK‐STAT3, TNF‐α‐Signalling‐VIA‐NF‐κB, COMPLEMENT, NOTCH Signalling and PI3K‐AKT‐mTOR pathways. Conclusion Melatonin attenuated DPSC senescence caused by long‐term expansion by inhibiting MMP3.