Prenatal maternal stress induces increased avoidance behavior in adolescent mice offspring

Defensive behavior is an instinctive response to potential or actual threats, crucial for the survival and reproduction of species. It is influenced by both genetic and environmental factors and undergoes continuous changes throughout an individual's development. Stress, as a significant environmental factor, has a profound and enduring impact on reshaping an individual's behavior, particularly when experienced during early life. However, the effects of early life stress on defensive behavior remain unclear. In this study, defensive behaviors were evaluated in adolescent mice offspring exposed to prenatal stress. Serum corticosterone and neural dendritic spine density were measured. Behaviors results showed that prenatal stress significantly increased anxiety-like and avoidance behaviors in male offspring mice. Enzyme-linked immunosorbent assay (ELISA) results indicated that prenatal stress led to a significant increase in serum corticosterone levels in male offspring following predator odor exposure. Golgi staining analysis revealed a decrease in neural dendritic spine density in the medial prefrontal cortex (mPFC) of offspring. These findings suggest that behavioral changes in offspring mice caused by prenatal stress may be related to alterations in corticosterone levels and neuronal structure. However, the causation and specific mechanisms require further investigation.