Stem cell and tissue regeneration analysis in low-dose irradiated planarians treated with cerium oxide nanoparticles.

Owing to the self-renewing reactive oxygen species scavenger capability of cerium oxide nanoparticles (nanoceria), we tested in vivo radioprotective effects on stem cells and tissue regeneration using low-dose irradiated planarians as model system. We treated planarians with nanoceria or gum Arabic, as control, and we analyzed the expression of stem cell molecular markers and tissue regeneration capability, as well as cell death and DNA damage in non-irradiated and in low-dose irradiated animals. Our findings show that nanoceria increase the number of stem cells and tissue regenerative capability, and reduce cell death and DNA damage after low-dose irradiation, suggesting a protective role on stem cells.