A Markov Clustering (MCL) algorithm was applied to identified proteins with abundance changes involved in PD (rno05012), NAFLD (rno04932), selected antioxidant enzymes (included in Table 1), PPAR signaling pathway (rno03320), processing in ER (rno04141), proteasome (rno03050), cytochrome P450 metabolism (rno00980), and selected proteins involved in apoptosis (caspase 6 (CASP6) and apoptosis-inducing factor 1, mitochondrial (AIFM1)) to show the associations among them, using de STRING protein-protein interaction database. This evidence concerns the gene CASP6 and Parkinson disease.