Finally, a single consumption of alcohol could lead to an addiction
According to researchers from the universities of Cologne, Mannheim and Heidelberg, a single drop of alcohol would be enough to create acute and lasting neuronal alterations in the brain. Alcohol affects the structure of synapses and the dynamics of mitochondria, an organelle that supplies cells with energy. This research was recently published in the journal Proceedings of the National Academy of Sciences.
As part of the study, Professor Henrike Scholz and members of her team, Michèle Tegtmeier and Michael Berger, used the genetic model of the fruit fly. They demonstrated that altering the movement of mitochondria across synapses dampens the pleasurable effect of alcohol. According to these results, even occasional consumption could cause alcohol dependence.
Most of the existing research concerns the consequences of chronic alcohol consumption on the hippocampus, the control center of the brain. That’s why this new research focused on brain changes when irregular drinking becomes chronic alcohol abuse.
A single dose of ethanol would create a favorable association with alcohol
According to the working hypothesis, a single administration of ethanol would generate a favorable link with alcohol. To test their theory, the researchers used fruit flies and mice. Their analysis revealed that ethanol altered mitochondrial dynamics as well as balance between synapses of neurons. Note that the mitochondria move in order to optimally distribute energy to the cells.
Cells treated with ethanol were disrupted in their movement. The chemical balance of some synapses has also been upset. These changes were permanent. Drosophila and mice consumed more alcohol and relapsed later.
“We sought to uncover ethanol-dependent molecular changes. These, in turn, form the basis of the permanent cellular changes that follow a single acute ethanol intoxication. The effects of a single administration of alcohol have been examined at molecular, cellular and behavioral levels. »
Henrike Scholz
Plasticity would contribute to the development of addictive behavior
Learning and memory require modification of the very structure of the brain. During this change, new connections between neurons are formed. It’s about brain plasticity. This mechanism would also be the basis for the formation of associative memories for sensations. “pleasant” that drugs provide.
Some of the morphological changes observed would influence the creation of ethanol-related memory. Given the presence of mitochondrial migration in neurons and plasticity, researchers hypothesize that these ethanol-dependent cellular changes promote the development of addictive behaviors.
