Parkinson’s occurs when nerve cells in the brain become depleted. This light micrograph shows mouse neurons labelled with a fluorescent protein to distinguish between cells at different depths DR GOPAL MURTI/SCIENCE PHOTO LIBRARY A mystery drug has shown promise for Parkinson’s disease , improving the mobility and balance of mice with Parkinson’s-like symptoms. The drug works by boosting the brain’s waste disposal system to remove toxic protein clumps, but the researchers behind the work aren’t yet revealing what the treatment is, referring to it only as compound X. “We aim to put some [intellectual property] protection around the repurposing of compound X as it has shown significant findings so far, and could become the first disease-modifying treatment for Parkinson’s disease,” says Zhao Yan at the Swinburne University of Technology in Melbourne, Australia.…