Ionizing Radiation Induces Senescence and Differentiation of Human Dental Pulp Stem Cells

Havelek, Radim; Soukup, T.; Ćmielová, J.; Seifrtová, M.; Suchánek, J.; Vávrová, J.; Mokrý, J.; Muthná, D.; Řezáčová, M.

doi:10.14712/fb2013059050188

Folia Biologica > Archive > 2013, Vol. 59 > Issue 5 > Ionizing Radiation Induces Senescence…

Fol. Biol. 2013, 59, 188-197

https://doi.org/10.14712/fb2013059050188

Ionizing Radiation Induces Senescence and Differentiation of Human Dental Pulp Stem Cells

Radim Havelek^1,2, T. Soukup³, J. Ćmielová¹, M. Seifrtová¹, J. Suchánek⁴, J. Vávrová⁵, J. Mokrý³, D. Muthná¹, M. Řezáčová¹

¹Department of Medical Biochemistry, Faculty of Medicine in Hradec Králové, Charles University in Prague, Hradec Králové, Czech Republic
²Faculty of Chemical Technology, University of Pardubice, Department of Biological and Biochemical Sciences, Pardubice, Czech Republic
³Department of Histology and Embryology, Faculty of Medicine in Hradec Králové, Charles University in Prague, Hradec Králové, Czech Republic
⁴Department of Dentistry, Faculty of Medicine in Hradec Králové, Charles University in Prague, Hradec Králové, Czech Republic
⁵Faculty of Military Health Sciences, University of Defence, Department of Radiobiology, Hradec Králové, Czech Republic

Received March 2013
Accepted June 2013

Head and neck cancer is one of the most common cancers in Europe. Many current anti-cancer treatments, including ionizing radiation, induce apoptosis via DNA damage. Unfortunately, such treatments are non-selective to cancer cells and produce similar toxicity in normal cells, including adult stem cells. One of the fundamental properties of an adult stem cell is that it does not have any tissue-specific structures that allow it to perform specialized functions. However, under certain stimuli, unspecialized adult stem cells can give rise to specialized cells to generate replacements for cells that are lost during one’s life or due to injury or disease. Nevertheless, specialization of stem cells must be controlled by specific milieu and also initiated at the proper time, making the entire process beneficial for tissue recovery and maintaining it for a long time. In this paper we assess whether irradiated dental pulp stem cells have maintained open their options to mature into specialized cells, or whether they have lost their unspecialized (immature) state following irradiation. Our findings showed radiation-induced premature differentiation of dental pulp stem cells towards odonto-/osteoblast lineages in vitro. Matrix calcification was visualized from Day 6 or Day 9 following irradiation of cells expressing low or high levels of CD146, respectively.

Keywords

dental pulp stem cells, ionizing radiation, radiation-induced premature differentiation, dentinogenesis, osteogenesis.

Funding

This study was supported by the program PRVOUK P37/01 of Charles University in Prague. R. Havelek and J. Čmielová are co-financed by the European Social Fund and the state budget of the Czech Republic. Project Nos. CZ.1.07/2.3.00/30.0058 (R.H.) and CZ.1.07/2.3.00/30.0022 (J.Č.).