Child Abuse May Alter Myelination in the Anterior Cingulate Cortex
For the latest McGill study, researchers in Canada used advanced microscopy techniques to measure the thickness of myelin sheaths surrounding ACC neurons in various cohorts. By comparing the brains of depressed suicides (both with or without a history of severe child abuse) to the brains of healthy controls, the researchers unearthed noticeable myelination differences in the ACC.
Notably, the brains of healthy controls, who had not been abused as children, contained a much thicker layer of myelin in the ACC. Thicker myelin sheaths optimize the ability of white matter tracts to communicate efficiently within and between brain regions.
This state-of-the-art research on child abuse and myelin in the ACC was conducted by Naguib Mechawar and Gustavo Turecki of the McGill Group for Suicide Studies (MGSS). Mechawar shared these findings in a lecture, “The Impact of Child Abuse on Oligodendrocytes and Myelination in the Human Brain,” as part of a symposium, “Novel insights on the neurobiology of depression,” on May 14 at the 12th Annual Canadian Neuroscience Meeting in Vancouver.
“Our results demonstrate that gene expression is strongly altered in a class of cells called oligodendrocytes in the ACC. This class of cells is responsible for producing myelin, which is an insulating compound that can be likened to the coating on electrical wires. Myelin-coated axons transmit nerve impulses efficiently, while a loss of myelin is generally associated with loss of transmission efficiency,” Mechawar said in a statement. “Our data clearly shows how severe child abuse modifies the architecture of the ACC by affecting the formation of the myelin sheath around neurons. This modification in a region that is key for mood regulation may underlie the increased vulnerability of abused individuals to mood disorders, such as depression.”