Category: Parkinson's Disease: Non-Motor Symptoms
Objective: In the present study, we investigated Lewy pathology in the enteric nervous system (ENS) of seven Parkinson’s disease (PD) patients who underwent a gastrectomy, gastric polypectomy, or colonic polypectomy before the onset of motor symptoms (premotor phase), to examine whether the presence of pathological αSyn can be a predictor for PD.
Background: Parkinson’s Disease is a neurodegenerative disorder characterized by motor and non-motor impairments, including constipation. Lewy bodies and neurites, the pathological hallmarks of PD, are found in both the central and enteric nervous systems (ENS). Recent reports have shown the accumulation of α-synuclein (αSyn) in the ENS of PD patients, prior to the onset of motor symptoms.
Method: Tissue samples from patients with prodromal PD (n = 7) and control patients (n = 22) were fixed in 10% formalin, dehydrated, and then embedded in paraffin blocks. Immunohistochemistry was performed using the primary antibodies against αSyn and phosphorylated αSyn (pαSyn). In three patients with prodromal PD, the muscularis externa was examined.
Results: In all control patients, the accumulation of αSyn was observed in the myenteric plexus in both the stomach and the colon, but there was no pαSyn deposition in the ENS. However, in patients with prodromal PD, an abundant accumulation of αSyn was observed in the myenteric plexus. Additionally, in all examined patients with prodromal PD, pαSyn-positive aggregates were observed in the nerve fibers in the muscularis externa. In the submucosal plexus, the accumulation of αSyn and the deposition of pαSyn were observed in four (57%) and one (14%) of the seven patients with prodromal PD, respectively.
Conclusion: We confirmed the presence of Lewy pathology in the premotor phase of PD. Our results suggest that detection of pαSyn, not αSyn, in the muscularis externa of the gastrointestinal tract may be a more sensitive biomarker to identify prodromal PD.
To cite this abstract in AMA style:
G. Beck, H. Mochizuki. Deposition of phosphorylated α-synuclein in the muscularis externa of the gastrointestinal tract in patients with prodromal Parkinson’s disease [abstract]. Mov Disord. 2020; 35 (suppl 1). https://www.mdsabstracts.org/abstract/deposition-of-phosphorylated-%ce%b1-synuclein-in-the-muscularis-externa-of-the-gastrointestinal-tract-in-patients-with-prodromal-parkinsons-disease/. Accessed October 19, 2025.« Back to MDS Virtual Congress 2020
MDS Abstracts - https://www.mdsabstracts.org/abstract/deposition-of-phosphorylated-%ce%b1-synuclein-in-the-muscularis-externa-of-the-gastrointestinal-tract-in-patients-with-prodromal-parkinsons-disease/