“It’s like they forgot they were dependent,” Olivier George, leader of a new study published in The Journal of Neuroscience, says of the alcohol-addicted subjects in a new animal model study.
Scientists believe that fermented beverages were first brewed as early as the seventh millennium B.C.E. Other scientists now say that they have finally discovered a way to completely remove the compulsion to drink in an alcohol-addicted animal model. Could this be the end of dependence on fermented beverages after humankind’s thousands of years of dealing with problems caused by alcoholism?
The researchers from The Scripps Research Institute (TSRI) say their new study was built on earlier work that indicated that a certain subset of neurons in the amygdala, making up just 5 percent of the amygdala’s total neurons, have been shown to become activated by frequent alcohol consumption. More frequent drinking further reinforces the neuronal circuit, driving the addiction to alcoholic beverages.
TSRI researchers successfully controlled these neurons, and consequently the subjects’ drive to drink.
— onmedic global (@onmedicglobal) September 7, 2016
Lead author Giordano de Guglielmo designed the rat model. The alcohol-activated neurons were made to express a specific protein so that the team could observe how these neurons behaved. Then, the scientists injected a compound to inactivate only the alcohol-linked neurons. Remarkably, those neurons were silenced and the dependence on alcohol was resolved.
The rats completely stopped consuming the alcohol. The results lasted for the duration of the study. The scientists say they do not believe the effect would be temporary.
They say they could hardly believe it, so they ran the study two more times. Each time, the need for alcohol completely disappeared in the animal models.
— Olivier George (@TSRIGeorgeLab) September 7, 2016
“It’s like they forgot they were dependent,” author Olivier George said according to Medical News Today. George told the outlet that “with classic pharmacology we usually observe a 20-40 percent decrease in drinking because the individuals are highly dependent (we model heavy alcoholism). Instead, here, the drinking went all the way back down to normal drinking, and without noticeable side effects; very unusual. And, usually, to have long lasting effects like that, you need daily treatment, not a single one; it shows that we might have found alcoholism’s Achilles’ heel.”
The brain’s reward system wasn’t turned off though. The researchers know this, because the animal subjects were still motivated to seek out sugar water. They simply stopped looking for alcohol.
Among the most surprising results though, is that the treated rats were also protected from the normal physical withdrawal symptoms that make going cold turkey so horrific for those addicted to alcohol.
The next studies are already in the works.
“We are now able to reversibly control these neurons with a laser using optogenetics. We can turn on and off drinking that way. We are also trying to find molecular targets in these neurons that could be targeted for medication development,” George said, adding that they are also testing nicotine and methamphetamine dependence in rats.
Giordano de Guglielmo said that targeting such a small population of neurons isn’t easy, but it also helped the researchers examine the differences on the brain between binge drinking and addictive consumption. Their trial of switching off alcohol-linked neurons didn’t affect the future drinking of non-dependent subjects. The researchers believe that with binge drinking, a hard neural pathway from alcohol to reward, isn’t established.
This study was funded by the NIH (grants AA006420, AA020608 and AA022977), the NIDA Intramural Research Program, and the TSRI Pearson Center for Alcohol and Addiction Research.
[Image via Pixabay]