In addition to CYP4B1 also CYPs 2C8, 2C9, 2S1 and 4F12 are involved in both, xenobiotic as well as fatty acid/eicosanoid metabolism, thus being on the interface of both metabolic pathways and possibly affecting the development of PD from both sides (Figure 1). Here, CYP4B1 is linked to Parkinson disease.