Washington: Heavy drinking in adolescence has lasting effects on the brain wiring, and may increase the risk of psychological problems and alcohol use disorder later in life, say scientists, including one of Indian origin. Researchers at the University of Illinois in the US have shown that some of these lasting changes are the result of epigenetic changes that alter the expression of a protein crucial for the formation and maintenance of neural connections in the amygdala — the part of the brain involved in emotion, fear and anxiety.
Their results, published in the journal Translational Psychiatry, are based on the analysis of postmortem human brain tissue. Epigenetics refers to chemical changes to DNA, RNA or specific proteins associated with chromosomes that change the activity of genes without changing the genes themselves.
Epigenetic modifications are involved in the normal development of the brain, but they can be influenced by environmental or even social factors, such as alcohol and stress. These kinds of epigenetic alterations have been linked to changes in behaviour and disease, said Subhash Pandey, a professor at the University of Illinois.
The researchers looked at postmortem human amygdala tissue from the brains of 11 individuals who started drinking heavily before the age of 21 or early-onset drinkers; 11 individuals who started drinking seriously after the age of 21, known as late-onset drinkers; and 22 individuals with no history of alcohol use disorder. The average age of death of the individuals from whom the samples were taken was 58 years old for those without alcohol use disorder; 55 years old for early-onset drinkers; and 59 for late-onset drinkers.
