Early life stress and the programing of stress-coping abilities in juvenile rats

PALLARES MARÍA EUGENIA

virtual

Conferencia; XXXV Reunión Anual SAN 2020 VIRTUAL; 2020

Sociedad Argentina de Investigación en Neurociencias

Prenatal stress (PS) predisposes individuals to develop emotional disorders in later life, including depression and anxiety, which might be mediated by dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis response. However, to date, little studies have examined the effects of PS on stress coping abilities of younger individuals and it relevance for the early onset of stress-related disorders. In here we assessed the impact of PS on the emergence of anxiety-/depressive- like behaviors and HPA response to an acute stress in juvenile rats. We explored possible underlying molecular bases by changes in candidate stress-related genes and DNA-methylation levels in the hippocampus, a key structure in stress regulation. Also, we tested patterns of maternal behavior within early lactation. Stress during pregnancy enhanced pup-directed behavior of stressed dams. In the offspring, PS rats had enhanced stress-coping abilities than non-prenatally stressed rats. In the hippocampus, PS increased the expression of bdnf-IV and crhr1 although several sex differences changes on glucocorticoids and on BDNF receptors expressions were found. PS changes the hippocampal epigenetic landscape only in male offspring. Our results show that PS and maternal behavior induce dynamic alterations in the offspring that should be adaptive at younger ages, but potentially maladaptive in later life, highlighting the importance of including an ontogenetic approach when assessing the effects of PS.