SNCA and Parkinson disease: Leaky gut syndrome in PD could be an effect of complicated interactions between enteric inflammation, alpha-synucleinopathy, and an altered gut microbiota as increased intestinal permeability and reduced tight junction proteins have been observed to correlate with colonic alpha-synuclein accumulation, fecal inflammatory markers, and gut dysbiosis in PD patients and animal models of PD [66, 85, 87, 88].