title: Human umbilical cord blood-derived mesenchymal stem cells undergo cellular senescence in response to oxidative stress.
abstract: Since human mesenchymal stem cells (MSCs) are therapeutically attractive for tissue regeneration and repair, we examined the physiological responses of human umbilical cord blood-derived MSCs (hUCB-MSCs) to genotoxic stress. We found that that sublethal doses of reactive oxygen species (ROS) and ionizing radiation cause DNA damage and reduce DNA synthesis and cell proliferation in hUCB-MSCs, resulting in cellular senescence. In contrast, these physiological changes were limited in human fibroblast and cancer cells. Our data show that reduced activities of antioxidant enzymes, which may occur due to low gene expression levels, cause hUCB-MSCs to undergo cellular senescence in response to oxidative stress and ionizing radiation. Resistance of hUCB-MSCs to oxidative stresses was restored by increasing the intracellular antioxidant activity in hUCB-MSCs via exogenous addition of antioxidants. Therefore, the proliferation and fate of hUCB-MSCs can be controlled by exposure to oxidative stresses.
authors: Department of Biological Sciences, Seoul National University, Seoul, Korea.
authors: Eun
authors: E
authors: Ko
authors: Kyung Yong
authors: KY
authors: Lee
authors: Deog Su
authors: DS
authors: Hwang
mesh_terms: D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology; D002374:Catalase / Q000494:pharmacology; D016923:Cell Death; D049109:Cell Proliferation / Q000187:drug effects; D016922:Cellular Senescence; D020552:Comet Assay; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D005312:Fetal Blood / Q000166:cytology*; D005720:Gamma Rays; D006367:HeLa Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D018384:Oxidative Stress; D011092:Polyethylene Glycols / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000975:Antioxidants; D017382:Reactive Oxygen Species; C070295:catalase-polyethylene glycol; D011092:Polyethylene Glycols; D006861:Hydrogen Peroxide; D002374:Catalase