Impact of early life stress on the pathogenesis of mental disorders: relation to brain oxidative stress

Stress is an inevitable part of human life and it is experienced even before birth. Stress to some extent could be considered normal and even necessary for the survival and the regular psychological development during childhood or adolescence. However, exposure to prolonged stress could become harmful and strongly impact mental health increasing the risk of developing psychiatric disorders. Recent studies have attempted to clarify how the human central nervous system (CNS) reacts to early life stress, focusing mainly on neurobiological modifications. Oxidative stress, defined as a disequilibrium between the oxidant generation and the antioxidant response, has been recently described as a candidate for most of the observed modifications. In this review, we will discuss how prolonged stressful events during childhood or adolescence (such as early maternal separation, parental divorce, physical violence, sexual or psychological abuses, or exposure to war events) can lead to increased oxidative stress in the CNS and enhance the risk to develop psychiatric diseases such as anxiety, depression, drug abuse or psychosis. Defining the sources of oxidative stress following exposure to early life stress might open new beneficial insights in therapeutic approaches to these mental disorders.