This article is more than 5 years old. Information may no longer be current.

Child abuse impairs neurological development

Recent findings indicated child abuse, partly through epigenetic reprogramming of oligodendrocytes, impaired cortical myelination.

“Considerable clinical and epidemiological evidence shows that early-life adversity significantly increases the lifetime risk for stress-related psychiatric disorders, including depression and suicide,” Pierre-Eric Lutz, MD, PhD, of McGill University, Montreal, and colleagues wrote. “In particular, it has been suggested that this relationship may be mediated by various traits, including neuroticism, high levels of impulsivity and aggressive behaviors, and high anxiousness trajectories, which are typically observed in depressed individuals with a history of abuse. However, the neurobiological processes underlying this heightened vulnerability remain unclear.”

To determine if epigenetic, transcriptomic and cellular adaptations occur in the anterior cingulate cortex after child abuse, researchers analyzed postmortem brain samples from individuals with depression who died by suicide with (n = 27) or without (n = 25) a history of severe child abuse and 26 psychiatrically healthy controls.

A history of child abuse was associated with cell-type specific changes in DNA methylation of oligodendrocyte genes and global impairment of the myelin-related transcriptional program.

This association was not found among suicide completers with depression without a history of child abuse.

Participants with a history of child abuse exhibited a significant reduction in thickness of myelin sheaths around small-diameter axons.

“Our results...suggest that in humans, early-life experiences also have an impact on myelination, at least in the cingulate cortex,” the researchers wrote. “Because myelination has been shown to adapt to neuronal activity during motor learning, we speculate that this phenomenon may be similarly modulated in the social brain by the quality of life experiences. By threatening the development of healthy attachment patterns, early-life adversity may lastingly disrupt oligodendrocyte differentiation, cellular density, and transcriptional programming within the cingulate cortex, in part through epigenetic processes.” – by Amanda Oldt

Disclosure: The researchers report no relevant financial disclosures.