In vitro Assessment of the DNA Damage Response in Dental Mesenchymal Stromal Cells Following Low Dose X-ray Exposure

Frontiers in Public Health

Marjan Moreels¹  Sarah Baatout¹  Randy Vermeesen¹  Bjorn Baselet¹  Ivo Lambrichts¹  Liese Gilles²  Stéphane Lucas³  Niels Belmans⁴  Reinhilde Jacobs⁵  Jonas Welkenhuysen⁶  Benjamin Salmon⁷ 

[1] Belgian Nuclear Research Centre, Institute for Environment, Health and Safety, Radiobiology Unit, Mol, Belgium;Belgian Nuclear Research Centre, Institute for Environment, Health and Safety, Radiobiology Unit, Mol, Belgium;Environmental Risk and Health Unit, Flemish Institute for Technological Research (VITO), Mol, Belgium;Laboratory of Analysis by Nuclear Reaction (LARN/PMR), Namur Research Institute for Life Sciences, University of Namur, Namur, Belgium;Morphology Group, Biomedical Research Institute (BIOMED), Hasselt University, Diepenbeek, Belgium;Belgian Nuclear Research Centre, Institute for Environment, Health and Safety, Radiobiology Unit, Mol, Belgium;Oral and Maxillofacial Surgery, Dentomaxillofacial Imaging Center, Department of Imaging and Pathology, OMFS-IMPATH Research Group, and University Hospitals, Katholieke Universiteit Leuven, Leuven, Belgium;Department Dental Medicine, Karolinska Institutet, Huddinge, Sweden;PXL Tech, PXL, Diepenbeek, Belgium;Université de Paris, Orofacial Pathologies, Imaging and Biotherapies UR2496 Lab, Montrouge, France;Dental Medicine Department, AP-HP, Bretonneau hospital, Paris, France;

关键词: dental stem cell;    DNA damage response;    DNA double strand break;    low dose radiation exposure;    cell cycle;    cellular senescence;   

DOI  :  10.3389/fpubh.2021.584484

来源: Frontiers

【 摘 要 】

Stem cells contained within the dental mesenchymal stromal cell (MSC) population are crucial for tissue homeostasis. Assuring their genomic stability is therefore essential. Exposure of stem cells to ionizing radiation (IR) is potentially detrimental for normal tissue homeostasis. Although it has been established that exposure to high doses of ionizing radiation (IR) has severe adverse effects on MSCs, knowledge about the impact of low doses of IR is lacking. Here we investigated the effect of low doses of X-irradiation with medical imaging beam settings (<0.1 Gray; 900 mGray per hour), in vitro, on pediatric dental mesenchymal stromal cells containing dental pulp stem cells from deciduous teeth, dental follicle progenitor cells and stem cells from the apical papilla. DNA double strand break (DSB) formation and repair kinetics were monitored by immunocytochemistry of γH2AX and 53BP1 as well as cell cycle progression by flow cytometry and cellular senescence by senescence-associated β-galactosidase assay and ELISA. Increased DNA DSB repair foci, after exposure to low doses of X-rays, were measured as early as 30 min post-irradiation. The number of DSBs returned to baseline levels 24 h after irradiation. Cell cycle analysis revealed marginal effects of IR on cell cycle progression, although a slight G2/M phase arrest was seen in dental pulp stromal cells from deciduous teeth 72 h after irradiation. Despite this cell cycle arrest, no radiation-induced senescence was observed. In conclusion, low X-ray IR doses (< 0.1 Gray; 900 mGray per hour), were able to induce significant increases in the number of DNA DSBs repair foci, but cell cycle progression seems to be minimally affected. This highlights the need for more detailed and extensive studies on the effects of exposure to low IR doses on different mesenchymal stromal cells.

【 授权许可】

CC BY