Transgenerational epigenetic inheritance of the stress response in rats

Recent human and animal studies indicate that stressful experiences in utero may have long-term consequences on the future mental wellbeing of the offspring across several generations. Epigenetic mechanisms, such as microRNA expression and DNA methylation are prone to change in response to hostile environmental factors. The main goal of this study was to investigate transgenerational changes in gene and microRNA expression, as well as in DNA methylation patterns in the placenta and developing brain in response to stress in a rat model. Our results demonstrated that ancestral exposure to stress during gestation causes significant changes in gene expression as well as epigenetic changes in placenta and embryonic cortex in the F2 and F3 generations. In addition, our results showed that assessing changes in placenta can be used to predict pathological processes of the newborn brain, thus providing an opportunity for early diagnosis of neurological and psychiatric diseases.