Combined ionizing radiation exposure improves behavioral symptoms and modulates brain innate immune system activity in the Tau P301S mice line

Tauopathies are a group of neurodegenerative diseases associated with abnormal phosphorylation and aggregation of the microtubule-associated tau-protein. Currently, there is no pathogenetic treatment for tauopathies, but the process of neuroinflammation that accompanies the diseases appears to be a promising therapeutic target. According to the literature, ionizing radiation (IR) may be one of the effective tools to manage neuroinflammation. Here, we investigated the effects of combined ionizing radiation (γ-quanta and carbon-12 nuclei) on locomotor abilities and markers of microglia activation in the brain of transgenic Tau P301S mice line reproducing tauopathy. Irradiation led to improvement in behavioral symptoms of the mice: increased endurance (in the early symptomatic stage) and enhanced locomotor activity (in the terminal stage). At the same time, irradiation resulted in increased levels of pro-inflammatory and anti-inflammatory cytokines and chemokines in the cerebellum and, to a lesser extent, in the hippocampus of irradiated mice. The obtained data indicate a significant modulating effect of IR on the innate immune system, and also indicate a high potential of radiotherapy as a therapeutic method for the treatment of neurodegeneration.