Cocaine in high doses can make the brain eat itself with cells digesting their own insides

Cocaine use can trigger a process that causes the brain to eat itself, a study on mice has shown. A team from the Johns Hopkins University School of Medicine in Baltimore, the US, performed autopsies on mice to discover how cells are killed from high doses of cocaine. They examined nerve cells in mouse brains to build on previous research showing nitric oxide is involved in cocaine-induced cell death through interactions with a specific enzyme.

Solomon Snyder, author of the study to be published in the journal PNAS, said cells can die through "suicide" in three ways, all of which are chemically programmed and controlled by different proteins. One of these ways is known as 'autophagy', which is a cellular process that gets rid of debris that accumulate within the cell. The debris are enclosed in "bags", and when these bags fuse with other bags that are filled with acids, the contents of the cell degrade – and when this process gets out of control, it results in cell death.

Observing the physical changes in the cells in mice allowed researchers to see how cocaine causes cell death through out-of-control autophagy. Lead author Prasun Guha explained: "A cell is like a household that is constantly generating trash. Autophagy is the housekeeper that takes out the trash – it's usually a good thing. But cocaine makes the housekeeper throw away really important things, such as mitochondria, which produce energy for the cell." Researchers also found signs of autophagy in the brain cells of mice whose mothers received cocaine while pregnant.

However, this finding also allowed the researchers to better understand how they could use a known compound, CGP3466B, to interfere with this process, providing a possible antidote. That information gave us immediate insight into how we might use a known compound to interfere with that process and prevent the damage," Snyder said.

When they tested it in the mice, it halted cocaine-induced autophagy. This, they said, raises the possibility of developing new targeted drugs to surpress the toxicity of cocaine and treat adults and children from the drugs effect on the brain.