"Since cerebrospinal fluid circulates in and around the brain, the association with urate CSF levels strengthens the possibility that urate has a protective influence on the cells that degenerate in Parkinson's disease," says Michael Schwarzschild, MD, PhD, of MGH-MIND, the study's senior author. "Urate is a major antioxidant and it can protect brain cells in the lab, which makes this a compelling possibility; but we don't yet know if it's urate itself or some urate-determining factor that helps people with Parkinson's."

One unexpected observation was that the association of urate levels with disease progression was not seen in DATATOP trial participants who had received vitamin E, also a powerful antioxidant that had no effect on disease progression in the original study. The researchers speculate that vitamin E might block urate's effects or that the elevated doses in the DATATOP trial might have had a pro-oxidant effect, possibilities that need further investigation.

With the support of the Michael J. Fox Foundation, Schwarzschild and Ascherio, along with Parkinson Study Group colleagues from across the country, are conducting a multicenter Phase 2 trial at 10 centers. Enrolling 90 recently diagnosed patients, the SURE-PD trial will investigate whether treatment with the urate precursor inosine can safely increase urate levels with a goal of slowing disease progression. More information on this trial is available at pdtrials/en/browse/all/view/259.

"Because elevated urate levels have known health risks, including gout and kidney stones," Schwarzschild stresses, "urate elevation should only be attempted in the context of a closely monitored clinical trial in which potential benefits and risks are carefully balanced."

Source: Massachusetts General Hospital