Objective:To investigate the effects of Aralkylamine N-acetyltransferase(AANAT)and acetylserotonin O-methyltrans-ferase(ASMT)on the osteogenic differentiation of periodontal ligament stem cells(PDLSCs)and the related regulatory mechanisms.Methods:PDLSCs were isolated and cultured from freshly extracted healthy teeth,and transfected with si-AANAT,si-ASMT and negative control(si-NC),respectively.The silencing efficiency on AANAT and ASMT genes and the expression level of osteogenic differentiation related genes of PDLSCs were detected by RT-qPCR.Mitochondrial reactive oxygen species(mtROS)production was measured by flow cytometry and fluorescent probe MitoSOX.The relative content of mitochondrial DNA(mtDNA)was detected by RT-qPCR,the content of ATP was detected by ATP kit,mitochondrial membrane potential(MMP)was measured by JC-1 fluores-cent staining.Results:After transfection of PDLSCs with si-AANAT and si-ASMT,AANAT and ASMT genes in PDLSCs were effec-tively silenced.Suppression of AANAT and ASMT in PDLSCs significantly decreased the mRNA expression levels of OCN,RUNX2 and COL-1.After silencing the expression of AANAT and ASMT,the mtROS production of PDLSCs increased,while the mtDNA,intracellular ATP content and MMP levels decreased significantly.Conclusion:AANAT and ASMT affect the osteogenic differentia-tion potential of PDLSCs possibly via regulating the mitochondrial function.

Objective:To investigate the effects of Aralkylamine N-acetyltransferase(AANAT)and acetylserotonin O-methyltrans-ferase(ASMT)on the osteogenic differentiation of periodontal ligament stem cells(PDLSCs)and the related regulatory mechanisms.Methods:PDLSCs were isolated and cultured from freshly extracted healthy teeth,and transfected with si-AANAT,si-ASMT and negative control(si-NC),respectively.The silencing efficiency on AANAT and ASMT genes and the expression level of osteogenic differentiation related genes of PDLSCs were detected by RT-qPCR.Mitochondrial reactive oxygen species(mtROS)production was measured by flow cytometry and fluorescent probe MitoSOX.The relative content of mitochondrial DNA(mtDNA)was detected by RT-qPCR,the content of ATP was detected by ATP kit,mitochondrial membrane potential(MMP)was measured by JC-1 fluores-cent staining.Results:After transfection of PDLSCs with si-AANAT and si-ASMT,AANAT and ASMT genes in PDLSCs were effec-tively silenced.Suppression of AANAT and ASMT in PDLSCs significantly decreased the mRNA expression levels of OCN,RUNX2 and COL-1.After silencing the expression of AANAT and ASMT,the mtROS production of PDLSCs increased,while the mtDNA,intracellular ATP content and MMP levels decreased significantly.Conclusion:AANAT and ASMT affect the osteogenic differentia-tion potential of PDLSCs possibly via regulating the mitochondrial function.

The positive regulation of bone-forming osteoblast activity and the negative feedback regulation of osteoclastic activity are equally important in strategies to achieve successful alveolar bone regeneration. Here, a molybdenum (Mo)-containing bioactive glass ceramic scaffold with solid-strut-packed structures (Mo-scaffold) was printed, and its ability to regulate pro-osteogenic and anti-osteoclastogenic cellular responses was evaluated in vitro and in vivo. We found that extracts derived from Mo-scaffold (Mo-extracts) strongly stimulated osteogenic differentiation of bone marrow mesenchymal stem cells and inhibited differentiation of osteoclast progenitors. The identified comodulatory effect was further demonstrated to arise from Mo ions in the Mo-extract, wherein Mo ions suppressed osteoclastic differentiation by scavenging reactive oxygen species (ROS) and inhibiting mitochondrial biogenesis in osteoclasts. Consistent with the in vitro findings, the Mo-scaffold was found to significantly promote osteoblast-mediated bone formation and inhibit osteoclast-mediated bone resorption throughout the bone healing process, leading to enhanced bone regeneration. In combination with our previous finding that Mo ions participate in material-mediated immunomodulation, this study offers the new insight that Mo ions facilitate bone repair by comodulating the balance between bone formation and resorption. Our findings suggest that Mo ions are multifunctional cellular modulators that can potentially be used in biomaterial design and bone tissue engineering.
Bone Regeneration ; Cell Differentiation ; Ions/pharmacology* ; Molybdenum/pharmacology* ; Osteoclasts ; Osteogenesis ; Printing, Three-Dimensional ; Tissue Scaffolds/chemistry*