Inhibition of the SERCA protein prevents calcium variations in nerve cells ...
 

... and protects them from degeneration.

Article: Cell Study Provides Hope for Treatment of Parkinson's Disease.
Cell Study Provides Hope for Treatment of Parkinson's Disease

Research paper (open access): Alpha-synuclein aggregates activate calcium pump SERCA leading to calcium dysregulation.
Alpha‐synuclein aggregates activate calcium pump SERCA leading to calcium dysregulation | EMBO Reports

The SoPD blog has done a substantial post on this paper. I think this is because this discovery reveals another way by which the elimination/reduction of alpha-synuclein aggregates could be neuroprotective. The blog post includes some information on the alpha-synuclein immunotherapy trials of AFFiRiS and Prothena, and even a few words (in the comments section) on the ongoing CliniCrowd mannitol trial.

When SERCA goes berserker | The Science of Parkinson's

NB: Like a lot of SoPD posts, this one starts with a largely unrelated preamble. The actual post begins after the line (in bold) "What does this have to do with Parkinson's"