Childhood Adversity Increases Susceptibility to Addiction Via Immune Response

Posted on July 19, 2018

Childhood adversity permanently alters the peripheral and central immune systems, increasing the sensitivity of the body's immune response to cocaine. The study showed that exposure to psychosocial stress early in life altered the structure of immune cells and inflammatory signals in mice and led to increased drug-seeking behavior. Exposure to early psychosocial stress in mice, or a difficult childhood in humans, increased the immune response to cocaine in adulthood, revealing a shared mechanism in the role of immune response in the effects of early life stress on cocaine sensitivity in mice and humans.

The findings help explain why as many as 50 percent of people who experience childhood maltreatment develop addiction problems. The results in mice and humans suggest that exposure to adversity during childhood triggers activation of the immune system, leading to permanent changes that sensitize the immune system and increase susceptibility to the effects of cocaine in adulthood.

Early social stress altered the structure of microglia in the ventral tegmental area, a brain region important for the reward system and drug-seeking, and increased the response of microglia to cocaine. In the peripheral immune system, early social stress increased the release of inflammatory molecules from white blood cells, which was further amplified by exposure to cocaine.

The study also compared immune system function of 38 cocaine addicts and 20 healthy volunteers. Those who experienced childhood maltreatment had increased expression levels of genes important for immune system function. And the highest levels were found in cocaine addicts who had experienced a difficult childhood. The findings add to the growing collection of evidence from the research group for the negative effects of early life trauma on brain development.


Category(s):Addictions, Drug Addiction

Source material from Science Daily