Figure 3.

Evidence-based alterations in the sphingolipids’ catabolism pathway implicated in PD tissues. The overall changes show a decrease in the activity of the enzyme which is accompanied by increased levels of substrates [36,37,38,39,40,91]. Corresponding references for data, their percentage of changes and tissues of origin are contained in the Table 1. PD brain data are generated from definitive PD cases and, as such, they are considered more valuable than CSF or serum data in describing metabolic shifts. Green-colored arrow upward: increase; red-colored arrow downward: decrease; hyphen: no change. (Created with BioRender.com. accessed on 15 November 2021).