Session Information
Date: Monday, June 5, 2017
Session Title: Parkinson's Disease: Non-Motor Symptoms
Session Time: 1:45pm-3:15pm
Location: Exhibit Hall C
Objective: Assessment of severity of α-synuclein pathology in the circadian system in patients with Parkinson’s disease (PD).
Background: Circadian system is responsible for the 24-hour rhythm of physiological function. The central pacemaker is located in the suprachiasmatic nucleus (SCN) of the hypothalamus which regulates the production of melatonin (the main endogenous entraining agent) by the pineal gland. Evidence suggests a disruption of the circadian system in PD with important clinical implications in motor and non-motor symptoms. Although a disruption of melatonin secretion has been shown, the neuroanatomical site of dysfunction of the circadian system in PD remains unclear.
Methods: Formalin-fixed hypothalamic and pineal tissue was obtained from patients with a histological diagnosis of PD and sex- and age-matched healthy controls from the Queen Square Brain Bank archive. Vasointestinal peptide immunohistochemistry was used for identification of the SCN. α-Synuclein immunohistochemistry severity was assessed in the SCN and pineal gland tissue using a semiquantitative score (0-4) as per neuropathological criteria.
Results: A total of 13 SCNs and 17 pineal glands (from a total of 28 PD patients) were compared with 4 SCNs and 7 pineal glands from 11 controls. α-Synuclein pathology was present in 9 (69.2%) of the SCNs of PD patients but in none of the controls (p = 0.025). α-Synuclein pathology was only present in the pineal gland of 2 PD cases (11.8%) but in none of the controls, and its severity did not show any significant differences (p = 0.354).
Conclusions: Our study shows that Lewy body pathology is significantly more severe in the SCN but not in the pineal gland in PD patients comparing with healthy controls. These findings suggest that disruption of central regulation within the SCN (rather than melatonin production by the pineal gland) may be responsible of the altered circadian melatonin output in PD.
References:
- De Pablo-Fernandez, Breen DP, Bouloux P, et al. Neuroendocrine abnormalities in Parkinson’s disease. J Neurol Neurosurg Psychiatry 2016. [Epub ahead of print]
- Breen DP, Vuono R, Nawarathna U, et al. Sleep and circadian rhythm regulation in early Parkinson disease. JAMA Neurol. 2014 May;71(5):589-95.
To cite this abstract in AMA style:
E. De Pablo-Fernandez, J. Holton, T. Warner. Histological analysis of α-synuclein pathology in the circadian system in Parkinson’s disease [abstract]. Mov Disord. 2017; 32 (suppl 2). https://www.mdsabstracts.org/abstract/histological-analysis-of-%ce%b1-synuclein-pathology-in-the-circadian-system-in-parkinsons-disease/. Accessed May 19, 2025.« Back to 2017 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/histological-analysis-of-%ce%b1-synuclein-pathology-in-the-circadian-system-in-parkinsons-disease/