Novel insights into prenatal irradiation-induced early and late brain defects

Brain development is a protracted and tightly regulated sequence of events. Any perturbation of these timed processes might cause detrimental consequences for the adult brain, in particular for its structure and functionality. Ionising radiation is able to perturb brain development. This was shown in prenatally exposed atomic bomb survivors of Hiroshima and Nagasaki. Irradiation to the unborn child resulted in long-term neurological defects, such as an increased incidence of mental disability, growth retardation and microcephaly. Animal studies were used to elucidate underlying mechanisms but have up to now failed to provide a coherent picture of radiation-induced injury to the brain. This PhD thesis aimed at improving the understanding on the structure-function relationship in the prenatally exposed brain and on the causal role of short-term effects in the induction of late sequelae of in utero irradiation. Importantly, we also envisioned to unravel possible effects of low doses of radiation (≤0.10 Gray (Gy)), of major importance for the improvement of radiation protection strategies for expecting mothers and their unborn child.