An exciting experimental drug developed by scientists at Johns Hopkins Medicine has been found to stop the progression of Parkinson's disease in live mice models. The new drug could be the first medication to specifically slow the progression of the devastating disease as opposed to current treatments that only target the symptoms.

Microglia are a kind of immune cell primarily found in the brain. One of the neurodegenerative processes that occurs in the brains of Parkinson's disease patients is when the microglial cells send chemical signals to another kind of brain cell called astrocytes. This signal spurs those astrocytes into more aggressive behaviors, eating away at connections between neurons.

"The activated astrocytes we focused on go into a revolt against the brain," explains Ted Dawson, one of the researchers on the project, "and this structural breakdown contributes to the dead zones of brain tissue found in those with Parkinson's disease. The idea was that if we could find a way to calm those astrocytes, we might be able to slow the progression of Parkinson's disease."

The compelling new drug the researchers developed is called NLY01, and it is similar to a group of drugs already used in humans to manage insulin levels for type 2 diabetes. Early experiments from the Johns Hopkins team found that human microglia treated with NLY01 effectively switched its negative signals off and ceased transforming healthy astrocytes into aggressive and damaging ones.

The next step was to verify the drug's effectiveness in mouse models simulating Parkinson's disease. Two separate mouse models were used to evaluate the drug's efficacy, and in both models NLY01 successfully either slowed neurodegenerative progression, or stopped it entirely. One experiment with transgenic mice engineered to simulate the degeneration of the disease showed the animals living 120 days longer than their untreated counterparts, a full 30 percent longer life expectancy.

The next stage of the process will be human clinical trials, initially beginning testing the safety profile of the compound. Dawson is confident that early safety trials should be rapid due to the similarity of the compound to existing drugs already proved safe for use in humans. Whether the compound works effectively in human subjects is yet to be seen, but this is undoubtedly an exciting step forward in developing a drug that can slow the onset of this devastating disease that affects one million people in the United States alone.

The study was published in the journal Nature Medicine.