Nav: Home

Surprising brain change appears to drive alcohol dependence

April 12, 2017

LA JOLLA, CA - April 12, 2017 - A new study led by scientists at The Scripps Research Institute (TSRI) could help researchers develop personalized treatments for alcoholism and alcohol use disorder.

The research reveals a key difference between the brains of alcohol-dependent versus nondependent rats. When given alcohol, both groups showed increased activity in a region of the brain called the central amygdala (CeA) -- but this activity was due to two completely different brain signaling pathways.

TSRI Professor Marisa Roberto, senior author of the new study, said the findings could help researchers develop more personalized treatments for alcohol dependence, as they evaluate how a person's brain responds to different therapeutics.

The findings were published recently online ahead of print in The Journal of Neuroscience.

Researchers Find Brain's Alcohol Response 'Switch'

The new research builds on the Roberto lab's previous discovery that alcohol increases neuronal activity in the CeA. The researchers found increased activity both nondependent, or naïve, and alcohol-dependent rats.

As they investigated this phenomenon in the new study, Roberto and her colleagues were surprised to find that the mechanisms underlying this increased activity differed between the two groups.

By giving naïve rats a dose of alcohol, the researchers engaged proteins called calcium channels and increased neuronal activity. Neurons fired as the specific calcium channels at play, called L-type voltage-gated calcium channels (LTCCs), boosted the release of a neurotransmitter called GABA. Blocking these LTCCs reduced voluntary alcohol consumption in naïve rats.

But in alcohol-dependent rats, the researchers found decreased abundance of LTCCs on neuronal cell membranes, disrupting their normal ability to drive a dose of alcohol's effects on CeA activity. Instead, increased neuronal activity was driven by a stress hormone called corticotropin-releasing factor (CRF) and its type 1 receptor (CRF1). The researchers found that blocking CeA CRF1s reduced voluntary alcohol consumption in the dependent rats.

Studying these two groups shed light on how alcohol functionally alters the brain, Roberto explained.

"There is a switch in the molecular mechanisms underlying the CeA's response to alcohol (from LTCC- to CRF1-driven) as the individual transitions to the alcohol-dependent state," she said.

The cellular and molecular experiments were led by TSRI Research Associate and study first author Florence Varodayan. The behavioral tests were conducted by TSRI Research Associate Giordano de Guglielmo in the lab of TSRI Associate Professor Olivier George.

Roberto hopes the findings lead to better ways to treat alcohol dependence. Alcohol use disorder appears to have many different root causes, but the new findings suggest doctors could analyze certain symptoms or genetic markers to determine which patients are likely to have CRF-CRF1 hyperactivation and benefit from the development of a novel drug that blocks that activity.
-end-
In addition to Roberto, Varodayan and de Guglielmo, authors of the study, "Alcohol dependence disrupts amygdalar L-type voltage-gated calcium channel mechanisms," were Marian Logrip and Olivier George of TSRI.

The study was supported by the National Institutes of Health (grants AA015566, AA021491, AA017447, AA006420, AA013498, AA020608, AA022977 and AA021802).

About The Scripps Research Institute

The Scripps Research Institute (TSRI) is one of the world's largest independent, not-for-profit organizations focusing on research in the biomedical sciences. TSRI is internationally recognized for its contributions to science and health, including its role in laying the foundation for new treatments for cancer, rheumatoid arthritis, hemophilia, and other diseases. An institution that evolved from the Scripps Metabolic Clinic founded by philanthropist Ellen Browning Scripps in 1924, the institute now employs more than 2,500 people on its campuses in La Jolla, CA, and Jupiter, FL, where its renowned scientists--including two Nobel laureates and 20 members of the National Academies of Science, Engineering or Medicine--work toward their next discoveries. The institute's graduate program, which awards PhD degrees in biology and chemistry, ranks among the top ten of its kind in the nation. In October 2016, TSRI announced a strategic affiliation with the California Institute for Biomedical Research (Calibr), representing a renewed commitment to the discovery and development of new medicines to address unmet medical needs. For more information, see http://www.scripps.edu.

Scripps Research Institute

Related Alcohol Articles:

Alcohol-induced deaths in US
National vital statistics data from 2000 to 2016 were used to examine how rates of alcohol-induced deaths (defined as those deaths due to alcohol consumption that could be avoided if alcohol weren't involved) have changed in the US and to compare the results by demographic groups including sex, race/ethnicity, age, socioeconomic status and geographic location.
Cuts in alcohol duty linked to 2000 more alcohol-related deaths in England
Government cuts to alcohol taxes have had dramatic consequences for public health, including nearly 2000 more alcohol-related deaths in England since 2012, according to new research from the University of Sheffield's School of Health and Related Research (ScHARR).
Potential novel biomarker for alcohol dependence
Specific molecules (small noncoding microRNAs or miRNAs) found in saliva may be able to predict alcohol dependence as biomarkers.
Integrated stepped alcohol treatment for people in HIV care improves both HIV & alcohol outcomes
Increasing the intensity of treatment for alcohol use disorder (AUD) over time improves alcohol-related outcomes among people with HIV, according to new clinical research supported by the National Institutes of Health.
The Lancet:Targets to reduce harmful alcohol use are likely to be missed as global alcohol intake increases
Increasing rates of alcohol use suggest that the world is not on track to achieve targets against harmful alcohol use, according to a study of 189 countries' alcohol intake between 1990-2017 and estimated intake up to 2030, published in The Lancet.
Alcohol-induced brain damage continues after alcohol is stopped
Now, a joint work of the Institute of Neuroscience CSIC-UMH, in Alicante, and the Central Institute of Mental Health of Mannheim, in Germany, has detected, by means of magnetic resonance, how the damage in the brain continues during the first weeks of abstinence, although the consumption of alcohol ceases.
Does alcohol consumption have an effect on arthritis?
Several previous studies have demonstrated that moderate alcohol consumption is linked with less severe disease and better quality of life in patients with rheumatoid arthritis, but a new Arthritis Care & Research study suggests that this might not be because drinking alcohol is beneficial.
How genes affect tobacco and alcohol use
A new study gives insight into the complexity of genetic and environmental factors that compel some of us to drink and smoke more than others.
Cutting societal alcohol use may prevent alcohol disorders developing -- Otago research reveals
Society must take collective responsibility to reduce the harm caused by alcohol use disorders, a University of Otago academic says.
The long-term effects of alcohol demand on retail alcohol markets
As new study by the Prevention Research Center of the Pacific Institute for Research and Evaluation and the Emory University Rollins School of Public Health, Department of Biostatistics examined the determinants of the number of licensed bars, restaurants, and liquor stores across neighborhoods in 53 California cities from 2000 to 2013.
More Alcohol News and Alcohol Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Uncharted
There's so much we've yet to explore–from outer space to the deep ocean to our own brains. This hour, Manoush goes on a journey through those uncharted places, led by TED Science Curator David Biello.
Now Playing: Science for the People

#556 The Power of Friendship
It's 2020 and times are tough. Maybe some of us are learning about social distancing the hard way. Maybe we just are all a little anxious. No matter what, we could probably use a friend. But what is a friend, exactly? And why do we need them so much? This week host Bethany Brookshire speaks with Lydia Denworth, author of the new book "Friendship: The Evolution, Biology, and Extraordinary Power of Life's Fundamental Bond". This episode is hosted by Bethany Brookshire, science writer from Science News.
Now Playing: Radiolab

Dispatch 2: Every Day is Ignaz Semmelweis Day
It began with a tweet: "EVERY DAY IS IGNAZ SEMMELWEIS DAY." Carl Zimmer – tweet author, acclaimed science writer and friend of the show – tells the story of a mysterious, deadly illness that struck 19th century Vienna, and the ill-fated hero who uncovered its cure ... and gave us our best weapon (so far) against the current global pandemic. This episode was reported and produced with help from Bethel Habte and Latif Nasser. Support Radiolab today at Radiolab.org/donate.