Wonder drug may treat cancer, addiction

UC IRVINE (US)—A drug in development to treat cancer could have the added benefit of helping prevent relapse in people trying to overcome cocaine addiction.

In mice conditioned to cocaine, drug-seeking activity was inhibited faster and to a greater extent with sodium butyrate than without it, neuroscientists at the University of California-Irvine say.

“Our results are exciting because sodium butyrate taps into fundamental molecular mechanisms, providing a novel approach to understanding and treating drug addiction,” says the study’s lead author Marcelo Wood, assistant professor of neurobiology and behavior.

People addicted to cocaine usually receive behavioral extinction therapy, in which they learn over time and without medication to disassociate a drug of abuse from the contexts and cues that are associated with it, but the process is lengthy and participants often drop out. Compounds tested previously to aid this therapy have had limited success, the researchers say.

For the study, Wood and colleagues placed mice in a container with three distinct chambers. The mice were given cocaine while in a particular chamber, and they quickly developed a preference for that location.

Then the cocaine was discontinued, and some of the mice were treated with sodium butyrate. Within 24 hours, those mice no longer sought out the cocaine chamber, but the untreated mice took more than a week to break from their chamber preference.

Later, the mice again were given cocaine prior to entering the chamber. The treated mice continued to show no preference, but the untreated mice quickly reverted to seeking out the cocaine chamber. “In a mouse, that’s relapse-like behavior,” Wood explains.

Previously, Wood and colleagues had found that sodium butyrate, a histone deacetylase inhibitor, can enhance long-term memory by relaxing the protein structure that organizes and compacts genomic DNA, allowing for easier and perhaps maintained activation of genes involved in memory storage.

“Because sodium butyrate works at this level, its effects may be much more stable” than other compounds, Wood says.

Researchers from Univeritat Jaume I in Spain and Oregon Health and Science University contributed to the study, which was funded in part by the National Institute on Drug Abuse and the National Institute of Mental Health. The study was published online in the journal Biological Psychiatry.

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