Skip to content

Aquaporin-4 Single Nucleotide Polymorphisms in Patients With Idiopathic and Familial Parkinson's Disease

Study on the Effects of Single Nucleotide Polymorphisms in Aquaporin-4 (AQP4) Gene on the Clinical Phenotype in Patients With Idiopathic and Familial Parkinson's Disease.

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04553185
Enrollment
733
Registered
2020-09-17
Start date
2018-11-28
Completion date
2026-04-30
Last updated
2026-05-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Parkinson Disease

Keywords

Parkinson's disease, AQP4, Glymphatic System, Genetics

Brief summary

The purpose of this study is to understand the relationship between problems in sleep, genetic variations in the Aquaporin-4 gene (AQP4), and the development of Parkinson's Disease.

Detailed description

Parkinson's Disease (PD) is a progressive neurodegenerative disease characterized by the abnormal deposition in the brain of aggregates called Lewy Bodies, packed with a protein called α-synuclein. The mechanisms why this protein accumulates in the brain of patients with PD, as well as its relationship with clinical symptoms, is unknown. Recently, an internal mechanism of drainage of waste proteins called glymphatic system has been identified and characterized. This system is silent during wakefulness and works during sleep. When it is active, a virtual space between the blood capillaries and cells of the brain called astrocytes opens and lets out waste products from the brain. This process is mediated by a protein of the astrocytes called Aquaporin-4 (AQP4). Preclinical studies have shown that the function of this system could be critical for the clearance of β-amyloid, a protein linked with the development of Alzheimer's Disease. Studies in humans have shown that genetic variations some parts of the AQP4 gene, defined as single nucleotide polymorphisms, may increase the likelihood to develop an aggressive form of Alzheimer's Disease. However, no studies in humans have ever been performed in Parkinson's disease and α-synuclein. In this study, the investigators aim to elucidate whether genetic variations in the AQP4 gene contribute to variations in the clinical presentation and progression of sporadic and genetic forms of Parkinson's disease. To do so, the genetic profile of patients will be determined through a small venous blood sample collection. This will be coupled with clinical and sleep assessment.

Interventions

All participants will undergo a collection of demographic data, personal and family history for PD, a neurological examination and administration of clinical scales. All participants will undergo a collection of venous blood sample. At the end of the visit they will receive a wristwatch to monitor their sleep at home (Actigraph) and a sleep diary, together with a prepaid envelope to post the watch and the diary back to the investigators. They will also receive a link for a series of online tests for non-motor symptoms related to Parkinson's disease that they can complete remotely at home.

Sponsors

University of Exeter
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
CROSS_SECTIONAL

Eligibility

Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No

Inclusion criteria

* 18-85 years of age * Able to give informed consent * Able to perform online neuropsychological examinations * Diagnosis of PD according to Brain Bank Criteria * No presence or personal or family history of other neurological or psychiatric disorders

Exclusion criteria

* Presence of other neurological disorders and known intracranial co-morbidities such as stroke, haemorrhage, space-occupying lesions * Inability to perform online neuropsychological assessment * Inability to have access to informatics technology to perform the online assessment tests * Inability to travel for the assessments * Native language different from English

Design outcomes

Primary

MeasureTime frameDescription
Association between genetic variations in the AQP4 gene and worse motor symptoms in PD patientsUp to 36 monthsThe presence of genetic variations in the AQP4 gene, measured with single nucleotide polymorphisms will be correlated, in idiopathic and familial PD patients, with higher (worse) scores on the Hoehn \& Yahr scales
Association between genetic variations in the AQP4 gene and worse cognitive symptoms in PD patientsUp to 36 monthsThe presence of genetic variations in the AQP4 gene, measured with single nucleotide polymorphisms will be correlated, in idiopathic and familial PD patients, with lower (worse) scores on Montreal Cognitive Assessment (MoCA) scale
Association between genetic variations in the AQP4 gene and worse sleep symptoms in PD patientsUp to 36 monthsThe presence of genetic variations in the AQP4 gene, measured with single nucleotide polymorphisms will be correlated, in idiopathic and familial PD patients, with worse sleep performances as assessed with sleep scales and Actigraph
Association between genetic variations in the AQP4 gene and worse non-motor symptoms in PD patientsUp to 36 monthsThe presence of genetic variations in the AQP4 gene, measured with single nucleotide polymorphisms will be correlated, in idiopathic and familial PD patients, with higher (worse) scores on scales for non-motor symptoms.

Secondary

MeasureTime frameDescription
Association between genetic variations in the AQP4 gene and altered levels of glymphatic system markers in PD patientsUp to completion of studyThe presence of genetic variations in the AQP4 gene, measured with single nucleotide polymorphisms will be correlated, in idiopathic and familial PD patients, with increased levels of blood concentration of LRP-1, ABCB1 and AQP4
Association between genetic variations in the AQP4 gene and altered levels of astrocyticUp to completion of studyThe presence of genetic variations in the AQP4 gene, measured with single nucleotide polymorphisms will be correlated, in idiopathic and familial PD patients, with increased levels of blood concentration of S100β
Association between genetic variations in the AQP4 gene and altered levels of protein aggregation markers in PD patientsUp to completion of studyThe presence of genetic variations in the AQP4 gene, measured with single nucleotide polymorphisms will be correlated, in idiopathic and familial PD patients, with increased levels of blood concentration of α-synuclein

Countries

United Kingdom

Contacts

STUDY_CHAIRMarios Politis, MD MSc PhD

University of Exeter

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: May 19, 2026