Early Signs of Parkinsons Disease in IBS

All study participants will give 3 study visits and questionnaires and faecal collection kits will be sent to them before the first visit. Visit 1: Study participants will undergo a sigmoidoscopy during which the researchers will collect 16 biopies. Twelve of the biopsies goes to ussing chamber studies of permeability while the remaining biopsies will be alliqoted for ultrastructural characterisation, alpha-synuclein aggregation assay and immunoflourescence. Blood samples will be drawn from the participants at this visits for metabolomic studies and platelet aggregation potential. In addition, study participants will also bring filled out questionnaires and faecal samples (microbiota analysis). Visit 2: Study participants will undergo a functional magnetic resonance imaging session for analysis of brain function. This visit will last for approximately 1 hour (preparations included). Visit 3: Participants will come in for a final sigmoidoscopy where the biopsies will be collected exclusively for performing the immuno-neurophenotyping of lamina propria lymphocytes.