Transgenerational Effects of Prenatal Stress on Memory and Expression of the Insulin-Like Growth Factor 2 Gene in the Offspring Brain

Prenatal maternal stress disrupts offspring behavior and cognitiveabilities not only in the first but also in subsequent generations.Various stress factors that affect fathers before conception canalso exert a similar transgenerational effect on the offspring phenotype.The aim of the study was to reveal the transgenerational effectof prenatal stress on female Wistar rats during gestational days 15-19on memory and insulin-like growth factor 2 (Igf2)gene expression in the brain of male and female offspring, as wellas the effect of additional stress exposure within the stress-restress paradigmin prenatally stressed male rats prior to mating with intact femaleson memory and Igf2 expressionin the brain of their offspring of both sexes. We demonstrated thatprenatally stressed males and their F1 male descendants showed improvedmemory in the passive avoidance test and increased Igf2 expression in the hippocampusand cerebral cortex. F1 female descendants of prenatally stressedmales, on the contrary, showed a decrease both in the duration ofmemory retention and in hippocampal and neocortical Igf2 expression. Additional stressexposure of prenatally stressed males prior to mating with intactfemales worsened memory and decreased the duration of its retention,as well as reduced Igf2 expressionin the brain of the offspring of both sexes. We concluded that thetransgenerational effects of prenatal stress on memory and Igf2 brain expression depend on thesex of the offspring, while prenatal stress per se contributes tomemory impairment and a decrease in Igf2 expressionin the offspring brain provided that such males were additionallystressed prior to mating.