AUG 06, 2018 5:10 PM PDT

Learning More About Addiction Relapse

WRITTEN BY: Carmen Leitch

Researchers studying cocaine addiction have managed to significantly reduce relapse rates in a preclinical model. To do so, a molecule called BDNF was delivered directly to a part of the brain that has a critical role in reward-seeking behavior, the nucleus accumbens, just before a rat model sought out cocaine. The findings have been reported by Medical University of South Carolina (MUSC) researchers in Addiction Biology.

This is the coca plant (Erythroxylum coca) and the molecular structure of cocaine (grey: carbon, blue: nitrogen, red: oxygen, white: hydrogen). / Credit: Max Planck Institute for Chemical Ecology/ D'Auria, Jirschitzka

"We discovered that a very common protein in the brain has an additional significant role in addiction relapse," said the lead author Ana-Clara Bobadilla, a postdoctoral scholar in the Kalivas lab at MUSC.

The nucleus accumbens is a small area where signals from various parts of the brain integrate and drive behaviors that fulfill reward-seeking needs. In a first, BDNF has been shown to have a beneficial role in reducing relapse when used at the right time. 

In an addiction model of rats, first they learn to self-administer cocaine after an auditory stimulus, then after a period of that behavior, they no longer hear the stimulus and cannot get to the cocaine. Then, the stimulus returns, and then the rats go for the cocaine again. This is meant to model situations such as when an addict in recovery visits a neighborhood where they bought drugs.

These models help scientists understand the proteins that are at work in the brain during these behaviors, and how they might be modulated to impede powerful addictions. BDNF has many critical roles in the brain, impacting memory, development and other functions. Lower than normal levels of BDNF have been observed in addicts, and the researchers wanted to know how it worked if it's used at the point of relapse, a new line of inquiry.

"An important aspect of this study is that while others have shown that BDNF is important for establishing the state of addiction, we find that can also be used to reverse addiction," noted Peter Kalivas, Ph.D., professor and chair in the Department of Neuroscience. "This exemplifies that the primary effect of BDNF is to promote changes in the brain and that this capacity to change the brain contributes to how people get addicted, but also can be harnessed to remove brain pathologies such as drug addiction."

"The most exciting realization is that this protein has a very fine-tuned effect and can be timing dependent," said Bobadilla. The location and timing of administration alter the impact of BDNF.

The role of BDNF in the nucleus accumbent can now be investigated to determine how the molecule reduces relapse, and whether it is effective in reducing relapse in other drug addiction models. The MUSC team has already found that it did not effectively work to impede food-seeking impulses, which use the same reward circuits in the brain. The effect of BDNF therefore, appears to be specific to drug abuse.

While this work fills in more of the gaps in our understanding of addiction, the Kalivas lab plans to continue the line of research. They are interested in how BDNF works on the various neurons within the nucleus accumbens and the influence of BDNF on them during relapse.

"What we are doing with these studies is mapping the brain. There are plenty of uncharted territories in our understanding of neurobiology and with this work, we provided results to fill in one of those unknown questions,” said Bobadilla. With a complete map of the brain, she said, it may be possible to cure addiction.

Learn more about the connection between the changes experienced by neurons in the brain and addiction from the video above, featuring Kalivas.


Sources: AAAS/Eurekalert! Via MUSC, Addiction Biology

About the Author
  • Experienced research scientist and technical expert with authorships on 28 peer-reviewed publications, traveler to over 60 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
DEC 11, 2019
Drug Discovery & Development
DEC 11, 2019
Drug Candidates for Alzheimer Disease May Reverse Effects of Aging
Researchers using mouse models of Alzheimer disease were able to demonstrate that the investigational drug candidates ‘CMS121’ and ‘J147&...
DEC 20, 2019
Neuroscience
DEC 20, 2019
Hand-Motion Center of the Brain Involved in Speech
During a long-term study focused on improving computer-assistant interfaces for quadriplegia patients, researchers at Stanford University were able to use...
DEC 30, 2019
Neuroscience
DEC 30, 2019
Amyloid Plaques May Not Come First in Alzheimer's
It’s commonly thought that excessive build-up of amyloid plaques, destroying the connections between nerve cells, is the first sign of Alzheimer&rsqu...
JAN 11, 2020
Cell & Molecular Biology
JAN 11, 2020
To Save Others, Bacteria Can Self-Destruct When Infected by a Virus
Scientists were studying viruses that infect and kill bacteria as a medicine for bacterial infections over a hundred years ago, and they are a focus of recent research as well....
JAN 20, 2020
Neuroscience
JAN 20, 2020
Ovarian Cancer Protein Accelerates Alzheimer's Neurodegeneration
Around 21,000 people in the US are diagnosed with ovarian cancer every year, while an estimated 5.8 million Americans have Alzheimer’s. Now, research...
JAN 26, 2020
Cell & Molecular Biology
JAN 26, 2020
Using Stem Cells to Treat Chronic Pain
Scientists have used a mouse model to show that human stem cells could be used to engineer neurons that stop pain....
Loading Comments...