Effect of age and extrinsic microenvironment on the proliferation and osteogenic differentiation of rat dental pulp stem cells in vitro.
BACKGROUND
It is suggested that dental pulp stem cells (DPSCs) possess pluripotent differentiation and self-renewal capacity and play a crucial role in maintaining dental pulp homeostasis. However, little is known about the age-related changes of DPSCs, and whether aging and its microenvironment are associated with DPSCs remains a question. In this study, age-related changes in proliferation and osteogenic differentiation ability of rat DPSCs were assessed.


METHODS
To examine the influence of microenvironment factors on different ages of DPSCs, we exposed adult rat DPSCs to juvenile rat dental pulp cell-conditioned medium (DPC-CM), and juvenile DPSCs were exposed to adult DPC-CM. Morphologic appearance, colony-forming assay, cell cycle analysis, 3-(4,5-dimethyl-thyazol-2-yl)-2,5-diphenyltetrazolium, gene expression, and mineralization assay after osteogenic induction of DPSCs were evaluated.


RESULTS
DPSCs isolated from the juvenile donors displayed increased proliferation and decreased osteogenic differentiation ability compared with the adult DPSCs. Interestingly, adult DPSCs induced by juvenile DPC-CM demonstrated enhanced proliferation but decreased osteogenic differentiation ability, whereas DPSCs from juvenile donors induced by adult DPC-CM showed decreased proliferation but enhanced osteogenic differentiation ability.


CONCLUSIONS
Our data suggest that age-related changes of DPSCs should be taken into account when DPSCs are intended to be used for investigations and application. Furthermore, the activity of DPSCs can be modulated by the extrinsic microenvironment.
Ma
Dandan
D
Department of Oral Histology and Pathology, School of Stomatology, Fourth Military Medical University, Shaanxi, China.
Ma
Zhaofeng
Z
Zhang
Xiaojun
X
Wang
Weihong
W
Yang
Zhenhua
Z
Zhang
Mi
M
Wu
Gang
G
Lu
Wei
W
Deng
Zhihong
Z
Jin
Yan
Y
D000469:Alkaline Phosphatase / Q000032:analysis; D000818:Animals; D015415:Biomarkers / Q000032:analysis; D002113:Calcification, Physiologic / Q000502:physiology; D002452:Cell Count; D018929:Cell Culture Techniques; D002453:Cell Cycle / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D048430:Cell Shape; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000502:physiology*; D018920:Coculture Techniques; D017077:Culture Media, Conditioned; D003782:Dental Pulp / Q000166:cytology*; D015870:Gene Expression / Q000235:genetics; D058574:Integrin-Binding Sialoprotein; D015675:Osteocalcin / Q000032:analysis; D010012:Osteogenesis / Q000502:physiology*; D039904:Pluripotent Stem Cells / Q000502:physiology; D016133:Polymerase Chain Reaction / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D012795:Sialoglycoproteins / Q000032:analysis; D013234:Stem Cells / Q000502:physiology*
D015415:Biomarkers; D017077:Culture Media, Conditioned; C546873:Ibsp protein, rat; D058574:Integrin-Binding Sialoprotein; D012795:Sialoglycoproteins; D015675:Osteocalcin; D000469:Alkaline Phosphatase