Though not directly associated with PD, PWPs take a lot of drugs and supplements, which may affect the Liver.
From that perspective, posting a rat study:
ncbi.nlm.nih.gov/pmc/articl...
Combination Treatment of Omega-3 Fatty Acids and Vitamin C Exhibited Promising Therapeutic Effect against Oxidative Impairment of the Liver in Methotrexate-Intoxicated Mice
Conclusions
The findings of this study demonstrated that the use of pretreatment with omega-3 and vitamin C provides significant hepatoprotective capacity against methotrexate-induced liver injury. This was observed by improving the oxidative damage of the liver through the depletion the serum level of MDA and enhancement of total antioxidant capacity, manifested by elevated serum level of SOD and GSH, reducing the level of intracellular liver enzyme ALT (which was the most prominent enzyme responsible for monitoring liver function). Furthermore, the current study illustrated the more synergistic effect of using a pretreatment combination of omega-3 (100 mg/kg) and vitamin C (100 mg/kg) to improve the oxidative tissue damage and liver functions affected by MTX-induced liver injury.