Colonic Alpha-Synuclein as Potential Early Biomarker for Parkinson's Disease Dementia

Document Type : Letter to the Editor


Faculty of Medicine, University Indonesia, Jakarta, Indonesia


Parkinson's Disease Dementia (PDD) is a cognitive and reasoning decline in many patients living with Parkinson's disease at least a year following diagnosis. PDD must be detected and treated promptly, as its advancement might impair the patient's quality of life. Alpha-synuclein deteriorates and extends to the limbic and neocortical regions in PDD, resulting in cognitive deficits. This development from PD to PDD may be associated with the quantity of aggregated alpha-synuclein in the colon. This also suggests employing the colonic alpha-synuclein cut-off concentration to detect the early progression of PD to PDD. Apart from concentration, the conformation of colonic alpha-synuclein can serve as a pathological hallmark. Despite the theoretical promise of colonic alpha-synuclein as an early diagnostic of PDD, the tissue sampling process may be a constraint. These restrictions, however, may be overcome with recent advancements in colonic biopsy technology. Thus, additional study is needed to close the information gap regarding using this biomarker as a possible early biomarker.


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