SNCA and Parkinson disease: Taken together, these data indicate that DSS-induced intestinal inflammation leads to a sex-dependent accumulation of total α-synuclein in colonic tissue, increase in α-synuclein+ macrophages in the colonic lamina propria, and elevation of phosphorylated α-synuclein loads within microglia of the SN, which all precede the sex-dependent onset of PD-related neuropathology and motor impairments in male hLRRK2G2019S Tg mice.