Human periodontal ligament stem cell seeding on calcium phosphate cement scaffold delivering metformin for bone tissue engineering
Zhao Z, Liu J, Schneider A, Gao X, Ren K, Weir MD, Zhang N, Zhang K, Zhang L, Bai Y, Xu HHK. J Dent
Tissue engineering strategies for craniofacial bone regeneration generally involve the actions of a scaffold material to support tissue regeneration, biologically active factors to instruct tissue formation, and cells to effect tissue formation. Among a variety of cell populations investigated for bone tissue regeneration, periodontal ligament-derived stem cells present the capacity to differentiate along an osteogenic lineage, and they can be harvested readily from extracted teeth. A recent article by Zhao et al. investigated the osteogenic differentiation of human periodontal ligament-derived stem cells cultured on calcium phosphate-based scaffolds releasing metformin as an osteogenic agent. The osteogenic differentiation of the cells was assessed by gene expression, alkaline phosphatase activity, and mineral deposition in culture, and three groups were investigated: blank scaffolds cultured in growth medium, blank scaffolds cultured in osteogenic medium, and metformin-loaded scaffolds cultured in osteogenic medium. The greatest osteogenic differentiation of the periodontal ligament-derived stem cells was observed with scaffolds releasing metformin in osteogenic medium. Overall, the study suggests that metformin enhances osteogenic differentiation without compromising the proliferative capacity of human periodontal ligament-derived stem cells. The results of the in vitro investigation provide interesting directions for continued investigation of human periodontal ligament-derived stem cells as a potential cell source and metformin as a potential osteogenic factor for craniofacial bone tissue engineering applications.