Drug-induced premature senescence model in human dental follicle stem cells

Abstract

Aging is identified by a progressive decline of physiological integrity leading to age-related degenerative diseases, but its causes is unclear. Human dental pulp stem cells (hDPSCs) has a remarkable rejuvenated capacity that relies on its resident stem cells. However, because of the lack of proper senescence models, exploration of the underlying molecular mechanisms has been hindered. Here, we established a cellular model utilizing a hydroxyurea (HU) treatment protocol and effectively induced Human dental pulp stem cells to undergo cellular senescence. Age-related phenotypic changes were identified by augmented senescence-associated-β-galactosidase (SA-β-gal) staining, declined proliferation and differentiation capacity, elevated G0/G1 cell cycle arrest, increased apoptosis and reactive oxygen species levels. Furthermore, we tested the expression of key genes in various DNA repair pathways including nonhomologous end-joining (NHEJ) and homologous recombination (HR) pathways. In addition, our results showed that Dental pulp stem cells from young donors are more resistant to apoptosis and exhibit increased non-homologous end joining activity compared to old donors. Further transcriptome analysis demonstrate that multiple pathways are involved in the HU-induced Dental pulp stem cells ageing, including genes associated with DNA damage and repair, mitochondrial dysfunction and increased reactive oxygen species levels. Taken together, the cellular model have important implications for understanding the molecular exploration of Dental pulp stem cells senescence and aging.

Hydroxyurea‐induced senescent peripheral blood mesenchymal stromal cells inhibit bystander cell proliferation of JAK2V617F‐positive human erythroleukemia cells

“…Noticeably, HU induces senescence‐like phenotype in several types of cells including transformed erythroleukemia cells, neuroblastoma, and hepatoma cells and primary cells such human fibroblast and human dental follicle stem cells , and in human PBMSC (this study). However, the influence of senescence MSC on other cells in the tumor microenvironment or circulating transformed cells has not been established yet.…”

Dental Mesenchymal Stem/Stromal Cells and Their Exosomes

“…Huang et al stressed the importance of the microenvironment for conversion of DP-MSCs into odontoblast-like cells, showing that DP-MSCs seeded onto dentin surfaces result in the formation of cells with odontoblastic morphologies [ 40 ]. Also, Zhai et al concluded from experiments with DP-MSCs damaged by hydroxyurea in vitro that DP-MSCs from young donors are more resistant to apoptosis and exhibit increased nonhomologous end joining DNA-repair activity compared to aged donors [ 41 ]. Cumulatively, it can be concluded that for the purpose of regenerative medicine, deciduous tooth pulp-derived cells are the best choice, not only because of their hardiness but also due to their robust expansion by cultivation in vitro.…”

Stem cells applications in bone and tooth repair and regeneration: New insights, tools, and hopes

“…Until most recently, identification of the underlying molecular mechanisms that control dental pulp stem cells senescence and aging was hindered, mostly because of the lack of proper senescence models. Zhai et al () have recently identified these age‐related phenotypic changes by augmented senescence‐associated‐β‐galactosidase (SA‐β‐gal) staining, elevated G0/G1 cell cycle arrest, increased apoptosis, and declined proliferation and differentiation capacity, as well as reactive oxygen species levels. This study has also shown that dental pulp stem cells from young donors are more resistant to apoptosis and exhibit increased non‐homologous end joining activity compared to old donors.…”

“…This study has also shown that dental pulp stem cells from young donors are more resistant to apoptosis and exhibit increased non‐homologous end joining activity compared to old donors. They have also shown that induced dental pulp stem cells ageing is dependent on several factors and pathways such as genes associated with DNA damage and repair, mitochondrial dysfunction, and increased reactive oxygen species levels (Zhai et al, ).…”