The impact of early-life stress on vulnerability and resilience to psychiatric disorders later in life.

Exposure to stress is a predominant environmental risk factor for psychiatric disorders. However, not all individuals experiencing stressful events will eventually develop a mental disease, and it may be due to a combination of numerous factors, including previous life experiences. Literature data indeed demonstrated that experiencing early-life adverse events can interfere with neurodevelopmental trajectories, which may result in altered susceptibility/resilience for the later psychiatric disorders development. In this talk I will discuss whether and how early-life stress may affect the stress response in adult rats. In particular, I will present data demonstrating that different early-life stressors show different programming effects on emotionality and cognitive functions, and that the exposure to such stressors may alter the ability to cope with a second challenge increasing (or decreasing) vulnerability for psychiatric disorders development later in life. Since sex hormones are known to affect the stress response system, I will also discuss sex differences involved in these processes. Investigating the programming effects of early-life stress exposure and the related neurobiological underpinnings could pave the way to the development of novel and precision-medicine based prophylactic and/or therapeutic interventions for psychiatric diseases in humans.