Summary: Relapse isn\u2019t a failure of willpower\u2014it\u2019s a biological \u201crewiring\u201d of the brain. A new study reveals how chronic cocaine use hijacks the connection between the brain\u2019s reward center and its memory hub (the hippocampus).<\/p>\n
Researchers identified a specific protein, DeltaFosB, that acts like a genetic master switch. As cocaine use continues, this protein accumulates, turning certain genes on and off to create a permanent, compulsive drive for the drug. By using CRISPR technology to pinpoint this mechanism, scientists have opened the door to a new class of \u201caddiction-breaking\u201d medications that could one day reset the brain\u2019s circuitry and prevent relapse.<\/p>\n
Key Facts<\/p>\n
The \u201cMaster Switch\u201d: The protein DeltaFosB accumulates in the brain\u2019s reward-memory circuit during chronic cocaine use, making it harder to quit and easier to relapse.Rewiring the Hippocampus: Cocaine use doesn\u2019t just change how you feel; it physically alters the hippocampus, the brain\u2019s memory center, linking drug-seeking behavior to deep-seated survival instincts.Calreticulin\u2019s Role: Researchers found a secondary gene, calreticulin, that is controlled by DeltaFosB and helps \u201crev the brain\u2019s engine\u201d to seek out more cocaine.No Approved Meds: Currently, there are no FDA-approved medications to treat cocaine addiction. This research identifies DeltaFosB as a primary target for future pharmaceutical therapies.CRISPR Insights: Scientists used specialized CRISPR technology to prove that DeltaFosB isn\u2019t just associated with addiction\u2014it is necessary for the brain changes that drive it.<\/p>\n
Source: Michigan State University<\/p>\n
When a cocaine addict relapses, it isn\u2019t a matter of personal failure \u2014 it\u2019s the biological result of their brain\u2019s rewiring, new research finds.<\/p>\n
Michigan State University scientists found that cocaine changes how the hippocampus functions, contributing to the ongoing compulsion to seek out the drug. Their National Institutes of Health-supported research, published in\u00a0Science Advances, not only explains why cocaine addiction is notoriously difficult to treat, but it could also help scientists develop new pharmaceutical therapies.<\/p>\n
\u201cAddiction is a disease in the same sense as cancer,\u201d said senior author\u00a0A.J. Robison, a professor of neuroscience and physiology. \u201cWe need to find better treatments and help people who are addicted in the same sense that we need to find cures for cancer.\u201d<\/p>\n
At least a million people nationwide struggle with cocaine addiction, and right now, there\u2019s no FDA-approved medication to treat it. People who stop using don\u2019t experience the same physical withdrawal symptoms that opiates cause, but that doesn\u2019t mean it\u2019s easy to quit. The drug hijacks the brain, flooding the reward centers with dopamine. This positive reinforcement tricks the brain into feeling like it\u2019s doing something good instead of destructive.<\/p>\n
Even if someone successfully quits, the odds aren\u2019t in their favor. About 24% relapse to weekly use, and another 18% return to a treatment program within a year.<\/p>\n
Andrew Eagle, a former postdoctoral researcher in Robison\u2019s lab and the paper\u2019s lead author, found a key player responsible for the compulsion \u2014 a protein called DeltaFosB. He used a specialized form of CRISPR technology to examine the role this protein plays in specific brain circuits when mice were exposed to cocaine.<\/p>\n
Using mouse models, he learned that this protein acts like a switch, turning genes on and off in the circuit between the brain\u2019s reward center and the hippocampus, the brain\u2019s memory hub. The longer someone uses cocaine, the more this protein accumulates in the circuit. This protein changes how the neurons function, altering how the circuit responds to cocaine.<\/p>\n
\u201cThis protein isn\u2019t just associated with these changes, it is necessary for them,\u201d Eagle said. \u201cWithout it, cocaine does not produce the same changes in brain activity or the same strong drive to seek out the drug.\u201d<\/p>\n
The research team also found another group of genes controlled by DeltaFosB after chronic cocaine use. One of those genes, called calreticulin, helps regulate how neurons communicate with each other. Their work showed calreticulin contributes to revving the brain\u2019s engine to compulsively seek out more cocaine.<\/p>\n
These findings in mouse models could have direct applications to humans, which share many of the same genes and similar circuits. Robison\u2019s lab is partnering with researchers at the University of Texas Medical Branch in Galveston, Texas, to create compounds that target DeltaFosB. Together, they have a grant from the National Institute of Drug Abuse to develop and test compounds that regulate DeltaFosB\u2019s ability to bind to DNA.<\/p>\n
\u201cIf we could find the right kind of compound that works in the right way, that could potentially be a treatment for cocaine addiction,\u201d Robison said. \u201cThat\u2019s years away, but that\u2019s the long-term goal.\u201d<\/p>\n
Next, Robison\u2019s lab will examine how hormones impact these brain circuits, and whether cocaine affects the male and female brain differently. This work could help explain biological differences in addiction risk between men and women.<\/p>\n
Key Questions Answered:Q: Is cocaine addiction a choice or a disease?<\/p>\n
A: This research confirms it is a biological disease. Chronic use physically alters the brain\u2019s genetic expression, creating a protein buildup that forces the brain to prioritize the drug over everything else. It\u2019s a \u201crewiring\u201d that willpower alone often cannot overcome.<\/p>\n
Q: Why is it so hard to stop \u201ccraving\u201d the drug even months later?<\/p>\n
A: Because the drug hijacks your memory center (the hippocampus). The protein DeltaFosB creates a long-lasting \u201cswitch\u201d in your neural circuits that stays flipped long after the drug has left your system, keeping the drive to seek it out active.<\/p>\n
Q: Is there a \u201ccure\u201d on the horizon?<\/p>\n
A: While we aren\u2019t there yet, researchers are currently developing compounds specifically designed to block DeltaFosB from binding to DNA. If successful, these could \u201creset\u201d the addicted brain and make long-term recovery much more achievable.<\/p>\n
Editorial Notes:This article was edited by a Neuroscience News editor.Journal paper reviewed in full.Additional context added by our staff.About this addiction and neuroscience research news<\/p>\n
Author: Bethany Mauger<\/a>
Source: Michigan State University<\/a>
Contact: Bethany Mauger \u2013 Michigan State University
Image: The image is credited to Neuroscience News<\/p>\n