Researchers Discover way to Erase Drug Memories, Offering Hope to Recovering Drug Addicts
Recovering drug addicts often struggle with memories that can sabotage their recovery. A discovery by scientists at the Scripps Research Institute (TSRI) Florida campus indicates there is a way to erase these drug-associated memories and prevent relapse to drug addiction, the TSRI reported.
“We now have a viable target and by blocking that target, we can disrupt, and potentially erase, drug memories, leaving other memories intact,” said Courtney Miller, TSRI associate professor.
New Drug Prevents Relapse
The study demonstrates the effectiveness of a single injection of a drug called blebbistatin in preventing relapse in animal models of methamphetamine addiction. The researchers published the study in an advance print of the journal, “Molecular Psychiatry.”
In 2013, Miller’s team discovered drug-associated memories could be erased by targeting actin. Actin is the protein that provides the structural scaffold supporting memories in the brain. However, the finding’s therapeutic potential seemed limited by the fact that actin is critically important throughout the body. Taking a pill that inhibits actin, even once, is likely to be fatal.
New Study Builds On Previous One
In the new study, the team found a safe route to selectively targeting brain actin through nonmuscle myosin II (NMII). NMII is a molecular motor that supports memory formation. The researchers used blebbistatin, a compound that acts on this protein. The team reported the finding as a major advance.
The results showed that a single injection of blebbistatin disrupted long-term storage of drug-related memories. It also blocked relapse in animal models of methamphetamine addiction for at least a month.
Erica Young, a research associate and a key author of the study, said a single injection of blebbistatin causes methamphetamine-associated memories to go away, along with dendritic spines, the structures in the brain that store memory.
No Need To Inject Drug Into The Brain
“Drugs targeting actin usually have to be delivered directly into the brain,” said research associate Ashley M. Blouin, another author of the study. Blebbistatin, however, reaches the brain even when injected into the body’s periphery and, importantly, the animals remained healthy.
The treatment’s effect was specific to drug-associated memories – not affecting other memories. The animals could still form new recollections.
The results argue for developing small molecule inhibitors of nonmuscle myosin II as potential therapeutics for relapse prevention, said research associate Sherri B. Briggs, another one of the study’s authors.
Other authors of the study include TRI’s Stephanie E. Sillivan, Michael D. Cameron and Gavin Rumbaugh.
The National Institute on Drug Abuse, the National Institute for Neurological Disorders and Stroke, the National Institute for Mental Health and the Brain and Behavior Research Foundation supports this research.
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