Brain ageing hastened by cocaine addiction: Study

Now, scientists from Germany and Canada have shown that in humans, cocaine use disorder (CUD) leads to changes in the ‘methylome’ of a subregion within the prefrontal cortex, Brodmann Area 9, thought to be important for self-awareness and inhibitory control. Typically, a greater degree of DNA methylation leads to the ‘dialing down’ of nearby genes.

Because the study of the brain methylome is invasive, the study was done on the cryo-preserved brains of 42 deceased male donors, of whom half had had CUD while the other half had not. The researchers found evidence that cells in Brodmann Area 9 appear biologically ‘older’ in people with CUD, evidence that these cells age faster than in people without substance use disorders. Here, they used patterns of DNA methylation as a measure of the biological age of cells in Brodmann Area 9. The biological age of cells, tissues, and organs can be greater or less than their chronological age, depending on diet, lifestyle, and exposure to disease or harmful environmental factors. Scientists can thus estimate the biological age from methylome data with established mathematical algorithms.

They also looked at differences in the degree of methylation at 654,448 sites in the human genome, and looked for associations with the presence or absence of CUD in the life of each donor. They corrected for differences in the donor’s age, the time since death, the brain pH, and further diseases such as depressive disorder and alcohol use disorder. They found 17 genomic regions that were more methylated in donors with CUD than in donors without CUD, and three regions that were less methylated in donors with CUD than in donors without CUD.

Reference:

Eric Poisel, et al,DNA methylation in cocaine use disorder – an epigenome-wide approach in the human prefrontal cortex,Frontiers in Psychiatry,doi 10.3389/fpsyt.2023.1075250