Cocaine was more harmful than alcohol

American scientists have discovered mechanisms of suppression of the gene in the brain with alcohol and drug abuse, harmful effects of cocaine was more extensive, according to an article in Proceedings of the National Academy of Sciences. Understanding what genes are and how involved in the formation of alcohol and drug dependence, it is necessary to find treatments for these pathologies. Molecular biologists from the National Institute of Health in Rockville, and the University of Miami School of Medicine, focused on the analysis of the gene in the hippocampus.

This area of ​​the brain responsible for translating the information from short-term memory into long-term, and also participates in the formation of drug dependence. Scientists studied the cells of the brain tissue 24 deceased men. A third of them during his life abusing cocaine, a third - of alcohol, the biological material from the rest served as controls. Preliminary analysis of 16,000 genes, working in the hippocampus, allowed to identify 1994 genes whose activity disrupted in people who are addicted to cocaine, and 1275 genes that go wrong with the brain of alcoholics.

In all samples of brain tissue, scientists have studied the number of mRNA molecules (the genetic "instructions" on the synthesis of proteins). This gives an indication of the genes (expression) - the more mRNA molecules, the more actively expressed a particular gene. In turn, the activity of genes depends, in part, on the spatial placement of the DNA molecule and on its chemical modification.

It turned out that the abuse of alcohol or cocaine may affect these processes. Previously it was shown that the activity of genes increases with the accession of the methyl groups CH3 to one of the histone proteins involved in the correct stacking of DNA necessary for the operation of genes. And cocaine, and alcohol hinders the formation of methylated forms of histone, which reduces the level of many genes - it was fairly clear by the number of mRNA molecules.

In this case, cocaine was more harmful than alcohol. The authors demonstrated that the use of this drug also leads to a violation of the expression of genes associated with the work of the mitochondria - the energy "factories" of living cells. This, in addition to other negative effects from the drug, leads to deterioration of brain energy supply.