Alcoholism's Molecular Effects Identified

While scientists have previously identified the changes to brain tissue and organs caused by alcoholism, a team of researchers has shown the long-term neurological effects of excessive drinking on a molecular level.

In a PLOS ONE study, Wayne G. Carter, a lecturer and principal investigator of medicine and health sciences at The University of Nottingham, and his co-contributors compared postmortem brain tissues of 20 alcoholics and 20 healthy donors.

By conducting hematoxylin and eosin staining and light microscopy on the prefrontal cortex, the researchers discovered deficiencies in α- and β-tubulin of the cytoskeleton and spectrin β II. Caused by the consumption of alcohol, a change in cytoskeletal structure affects neuronal cell organization, connection, and activity. This finding would explain the behavioral and cognitive differences in alcoholics, according to a statement from the university.

“Altered protein level and [post-translational modifications] of the cytoskeletal architecture, and also disruption of the functional activity of the Na⁺,K⁺-ATPase provides a molecular basis for some of the altered neuronal and behavioural manifestations encountered by alcoholics, and may also contribute to the atrophic brain macrostructure that is phenotypic of an alcoholic,” the researchers explained.

While the researchers also found a non-significant increase of isoaspartate protein damage, they discovered a noteworthy rise in isoaspartyl methyltransferase levels, which are responsible for in vivo repair to isoaspartate proteins.

Compared to control subjects, alcoholics had varying deficiencies of cytosolic α- and β-tubulins in the caudate nucleus, hippocampus, and cerebellum, the investigators reported. This finding indicates regional brain damage is caused by alcoholism, they added.

“Excessive alcohol consumption is a global social and financial healthcare problem of epidemic proportions,” Carter noted. “We have provided an insight into some of the tissue and cellular brain damage that arises in alcoholic patients. The hope is that we can improve the lives of alcoholics and reduce the number of deaths associated with alcoholism.”