IADR Abstract Archives
Prevention of Regressive Tissue Changes by Protection of Adult Stem Cell Pool
Objectives: Size of a pool of adult stem cells normally decreases during aging of an organism. However, environmental stressors (toxins, pollutants, mechanical force, hypoxia or hyperoxia and other) can decrease vitality of the adult stem cells or cause a decrease of their number by apoptosis and necrosis. We have used a cell culture model of mechanical stress and hypoxia to study mechanisms, by which dental stem cells react to damaging stimuli.
Methods: Human dental stem cells were isolated from dental pulp, periodontal ligament (PDL), submucosal connective tissue. Early changes of gene expression after application of stretch or relaxation to PDL cells were analyzed using real-time PCR and PCR expression assays. We have also studied effects of hypoxia on proliferation, migration and apoptosis of dental pulp stem cells.
Results: Strain combined with mild hypoxia (1% oxygen) led to almost general inhibition of gene expression. More severe hypoxia led to apoptosis of cells. On the other side, dental stem cells proliferated more rapidly in 5% oxygen "hypoxia" than in 21% oxygen "normoxia".
Conclusions: Studies on early mechanisms, by which adult stem cells react to negative environmental factors (endoplasmic reticulum stress and unfolded protein response) can show ways how to preserve a pool of adult stem cells till an old age. Building of atrophied alveolar bone is essential for successful placement of intraosseous implants. It is beneficial, if autologous adult stem cells can be used.
Methods: Human dental stem cells were isolated from dental pulp, periodontal ligament (PDL), submucosal connective tissue. Early changes of gene expression after application of stretch or relaxation to PDL cells were analyzed using real-time PCR and PCR expression assays. We have also studied effects of hypoxia on proliferation, migration and apoptosis of dental pulp stem cells.
Results: Strain combined with mild hypoxia (1% oxygen) led to almost general inhibition of gene expression. More severe hypoxia led to apoptosis of cells. On the other side, dental stem cells proliferated more rapidly in 5% oxygen "hypoxia" than in 21% oxygen "normoxia".
Conclusions: Studies on early mechanisms, by which adult stem cells react to negative environmental factors (endoplasmic reticulum stress and unfolded protein response) can show ways how to preserve a pool of adult stem cells till an old age. Building of atrophied alveolar bone is essential for successful placement of intraosseous implants. It is beneficial, if autologous adult stem cells can be used.