A medicine against Alzheimer's disease corrects brain damage caused by alcohol exposure in rats

A drug used to slow down cognitive decline in adults with Alzheimer's disease appears to reverse brain inflammation and neuronal damage in rats exposed to alcohol during adolescence.

In a study described in the newspaper Scientific reportsThe researchers at Duke Health have sought to understand how excessive occasional consumption of alcohol alters the seahorse, a region long recognized as essential for learning and memory, but also related to alcohol. anxiety, and whether the drug, donepezil, could reverse these changes. Rats have been used as a model for teenagers and young adults who drink excessively a few times a week.

"Research has begun to show that human adolescents who drink early and regularly throughout their teenage years have deficits in brain function that can affect learning and memory, as well as anxious and social behaviors" said senior author Scott Swartzwelder, Ph.D., professor of psychiatry at Duke.

"Changes can be subtle, but who wants even subtle deficits in their brain function or how they think and feel?" Swartzwelder said. "Studies on animal models show that alcohol exposure in adolescents can alter the way nerve cells communicate with each other and the level of plasticity of brain circuits, compromising the brain's ability to change. and to adapt.These changes can be observed at the adult age after the end of the alcohol exposure. "

Because they can not, ethically, entice young people to drink alcohol to study the effects, researchers are using the developing brain of rats to understand the effects of "l? "intermittent exposure to alcohol", which allows to obtain blood alcohol levels corresponding to those obtained by drinking teenagers. .

Scientists have observed that "in addition to brain inflammation, alcohol exposure in adolescents inhibited the birth of new neurons in the hippocampus," added Swartzwelder, et al. could even accelerate neuronal death, which would facilitate the loss of existing cells and make it more difficult to produce.

Once in adulthood, the rats received donepezil, a cognition-enhancing drug marketed under the brand name Aricept. After four days of treatment, the researchers studied the animals' brains, looking more closely at the hippocampus. Rats that received donepezil in adulthood after exposure to alcohol in adolescents exhibited less inflammation and a better ability to produce new neurons compared to rats. having not received treatment with donepezil.

"We do not know if the reversal of these effects of alcohol by donepezil is permanent, but at least temporarily, it reverses them," said Swartzwelder.

Swartzwelder said the study helps clarify the risk of excessive alcohol consumption among young adults, which is difficult to assess.

"It's obvious that all those who drink in adolescence do not grow up and fail completely in life," said Swartzwelder. "You may not notice deficits every day in an obvious way, but you run the risk of losing your advantage.Sometimes a small impairment of brain function can have a significant training effect in the life of your child. someone & # 39; a ".

Importantly, the research demonstrates the potential to repair some types of harm caused by alcohol exposure in adolescents, he said. But beyond that, it could also lead to a more specific understanding of the cellular mechanisms that make the developing brain particularly vulnerable to substances such as alcohol.