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Investigation of the Serotoninergic System in Multiple System Atrophy: a Positron Emission Tomography (PET) Study

Completed
Conditions
Multiple System Atrophy
Interventions
Radiation: PET (Positron Emission Tomography) Study
Other: Brain MRI (magnetic resonance imaging)
Registration Number
NCT01136213
Lead Sponsor
University Hospital, Bordeaux
Brief Summary

Multiple system atrophy (MSA) is a sporadic neurodegenerative disorder of the adult associated to a poor prognosis. MSA is clinically characterized by the association of extra-pyramidal, dysautonomic, cerebellar and pyramidal symptoms. Histological and biological studies have raised the hypothesis that, beside the well known dopamine deficiency, some of the symptoms could be related to a dysfunction in serotoninergic neurotransmission. Serotonin is involved in the modulation of several functions impaired in MSA, such as mood, motricity or sleep. The recent description of an association between loss of brainstem serotonin neurons and sudden death in patients with MSA reinforced the hypothesis of a critical role played by this neurotransmitter in the pathophysiology of this disease. Autoreceptors called 5-HT1a are strongly involved in the regulation of serotonin neurotransmission. During the last years several radio-ligands allowing in vivo PET quantification of 5-HT1a receptors, such as 18F-MPPF (4-(2'-methoxyphenyl)-1-\[2'-(N-2''-piridinyl)-p-fluorobenzamide\]methylpiperazine), were developed. Moreover, the investigators recently demonstrated the ability of this brain functional imaging method to investigate, in healthy volunteers, the functional properties of 5-HT1a autoreceptors through an evaluation of their desensitization after a single oral dose of fluoxetine.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
53
Inclusion Criteria
  • Patients with Multiple system atrophy (MSA)

    • MSA possible or probable
    • Male and female
    • Age : 30 to 80
    • No cognitive impairment
    • Unmodified treatment for 2 months
    • Able to give informed consent
    • Affiliated to social insurance
  • Patients with idiopathic Parkinson's disease (IPD):

    • Positive clinical criteria for IPD
    • Male and female
    • Age : 30 to 80
    • No cognitive impairment
    • Unmodified treatment for 2 months
    • Able to give informed consent
    • Affiliated to social insurance
  • Healthy controls:

    • Absence of neuropsychiatric disorder
    • Male and female
    • Age : 30 to 80
    • Able to give informed consent
    • Affiliated to social insurance
Exclusion Criteria
  • Patients with Multiple system atrophy (MSA)

    • Other Parkinsonian syndrome
    • Dementia
    • Recent intake (< 4 weeks or 8 weeks for fluoxetine) of medication acting on 5-HT1a receptors
    • History of major depression
    • Contraindication to brain MRI
    • Contraindication to PET
  • Patients with idiopathic Parkinson's disease

    • Other Parkinsonian syndrome
    • Dementia
    • Recent intake (< 4 weeks or 8 weeks for fluoxetine) of medication acting on 5-HT1a receptors
    • History of major depression
    • Contraindication to brain MRI
    • Contraindication to PET
  • Healthy controls:

    • Patient having a neuropsychiatric disease
    • Recent intake (< 4 weeks or 8 weeks for fluoxetine) of medication acting on 5-HT1a receptors
    • History of major depression
    • Contraindication to brain MRI
    • Contraindication to PET

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Volunteers without neuropsychiatric disorder (Control)Fluoxétine / Placebo-
Multiple system atrophyPET (Positron Emission Tomography) Study-
Idiopathic Parkinson DiseaseFluoxétine / Placebo-
Multiple system atrophyBrain MRI (magnetic resonance imaging)-
Idiopathic Parkinson DiseaseBrain MRI (magnetic resonance imaging)-
Volunteers without neuropsychiatric disorder (Control)Brain MRI (magnetic resonance imaging)-
Multiple system atrophyFluoxétine / Placebo-
Idiopathic Parkinson DiseasePET (Positron Emission Tomography) Study-
Volunteers without neuropsychiatric disorder (Control)PET (Positron Emission Tomography) Study-
Primary Outcome Measures
NameTimeMethod
18F-MPPF binding potential - Biding potential (BP) under placebo in the raphe nucleusSecond visit (day 1)

Amount of 5-HT1a autoreceptors (evaluated by measurement of 18F-MPPF binding potential) after intake of placebo in the raphe nucleus.

Secondary Outcome Measures
NameTimeMethod
Clinical parameters (motor handicap, orthostatic hypotension, quality of life, sleep, pain, tiredness)Third visit (day 30)
18F-MPPF binding potential - Biding potential (BP) under placebo in other brain areasThird visit (day 30)

Amount of 5-HT1a autoreceptors (evaluated by measurement of 18F-MPPF binding potential) after intake of placebo in other brain areas (brainstem, hippocampus, etc.).

18F-MPPF binding potential - Biding potential (BP) in other brain areasSecond visit (day 1)

Amount of 5-HT1a autoreceptors (evaluated by measurement of 18F-MPPF binding potential) in other brain areas (brainstem, hippocampus, etc.)

18F-MPPF binding potential - BP under fluoxetine in all brain areasThird visit (day 30)

Amount of 5-HT1a autoreceptors (evaluated by measurement of 18F-MPPF binding potential - BP) after intake of fluoxetine in all brain areas.

Trial Locations

Locations (3)

CHU Limoges

🇫🇷

Limoges, France

CHU de Bordeaux

🇫🇷

Bordeaux, France

CHU de Toulouse

🇫🇷

Toulouse, France

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