Brain Reactivity to Nitrous Oxyde in Depression : an MRI and Ultrasound Study (PROTOBRAIN Pilote)
NCT ID: NCT04199143
Last Updated: 2025-12-23
Study Results
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
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COMPLETED
NA
30 participants
INTERVENTIONAL
2020-02-20
2021-06-10
Brief Summary
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Ultrasound and MRI Neuroimaging will be measured before, during and after a single one-hour exposure of a 50%N20/50%O2 mixture, in depressed individuals (n=20) and healthy volunteers (n=10). We make the hypothesis that brain reactivity will be lower in depressed individuals nonresponders to N2O compared to responders and healthy controls. This study would provide further characterisation of the pathophysiology of the antidepressant response to N2O, as well as providing potential biomakers (Ultrasound and MRI) for treatment response to N2O in TRD.
Detailed Description
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* Ultrasound Tissue Pulsatility Imaging for assessment of Brain Tissue Pulsatility (BTP) which reflects reactivity in brain movements and mechanical brain properties
* MRI with structural and functional assessments, namely brain volumes, white matter lesions, ASL for brain perfusion and BOLD for resting-state connectivity and brain pulsatility
MRI will be performed before and after a single one-hour exposure of 50%N2O/50%O2 mixture. Ultrasound will be performed before, after and also during gas exposure. Changes in these neuroimaging parameters will constitute the primary assessment of the study. Psychometric and safety assessements will complete the neuroimaging outcomes.
Follow-up will includes 1) a baseline visit for baseline MRI and Psychometric assessements, 2) a second visit for gas exposure and neuroimaging assessements, 3) a third and fourth visits for psychometric and safety assessements, respectively 24 hours and one week after gas exposure.
Conditions
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Keywords
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Study Design
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NON_RANDOMIZED
PARALLEL
BASIC_SCIENCE
NONE
Study Groups
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healthy voluntary controls
A single Non-blinded One-hour administration of 50% Nitrous oxyde (N2O) 50%oxygen (O2) Gas Mixture
Nitrous Oxide-Oxygen
The medical product used in this study is a gas for common medical use in various domains including anesthesic, consisting in the equimolar mixture of nitrous oxide and oxygen. Subjects will receive a mixture of 50% N2O / 50% O2 for 1 hour.
Tissue Pulsatility Imaging - TPI
Tissue Pulsatility Imaging (TPI) is a variation of ultrasonic Doppler strain imaging we are developing to measure the local expansion and relaxation of the brain tissue over the cardiac cycle to characterize and image perfusion.
Magnetic Resonance Imaging - MRI
Structural and Functionnal (including BOLD and ASL) MRI will be aquired in this study
Depressive Patients
A single Non-blinded One-hour administration of 50% Nitrous oxyde (N2O) 50%oxygen (O2) Gas Mixture
Nitrous Oxide-Oxygen
The medical product used in this study is a gas for common medical use in various domains including anesthesic, consisting in the equimolar mixture of nitrous oxide and oxygen. Subjects will receive a mixture of 50% N2O / 50% O2 for 1 hour.
Tissue Pulsatility Imaging - TPI
Tissue Pulsatility Imaging (TPI) is a variation of ultrasonic Doppler strain imaging we are developing to measure the local expansion and relaxation of the brain tissue over the cardiac cycle to characterize and image perfusion.
Magnetic Resonance Imaging - MRI
Structural and Functionnal (including BOLD and ASL) MRI will be aquired in this study
Interventions
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Nitrous Oxide-Oxygen
The medical product used in this study is a gas for common medical use in various domains including anesthesic, consisting in the equimolar mixture of nitrous oxide and oxygen. Subjects will receive a mixture of 50% N2O / 50% O2 for 1 hour.
Tissue Pulsatility Imaging - TPI
Tissue Pulsatility Imaging (TPI) is a variation of ultrasonic Doppler strain imaging we are developing to measure the local expansion and relaxation of the brain tissue over the cardiac cycle to characterize and image perfusion.
Magnetic Resonance Imaging - MRI
Structural and Functionnal (including BOLD and ASL) MRI will be aquired in this study
Other Intervention Names
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Eligibility Criteria
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Inclusion Criteria
* A person who can undergo N2O diffusion via a facial mask.
* A person who has signed an informed consent.
* Person affiliated with a social security scheme.
* Major Depressive Episode according to DSM-5 criteria, confirmed by the MINI - International Neuropsychiatric Interview.
* Patients with an MADRS score greater than 20 (Montgomery
* Asberg Depression Rating Scale).
* Patients resistant to at least one well-conducted antidepressant treatment, as documented by the MGH-ATRQ scale.
* Absence of: bipolar disorder, schizophrenic disorder, neurodegenerative disease, schizophrenic disorder, neurodegenerative disease, addiction to one or more toxics documented by the MINI.
* Absence of: bipolar disorder, schizophrenic disorder, neurodegenerative disease, schizophrenic disorder, neurodegenerative disease, addiction to one or more toxics documented by the MINI, current or past.
Exclusion Criteria
* Presence of active and significant psychotic symptoms, at investigator's discretion
* Contraindications to mixture 50%N2O/ 50%O2: intracranial hypertension, altered state of consciousness, head trauma, pneumothorax, emphysema bubbles, abdominal gaseous distension, administration of less than 3 months of ophthalmic gas (SF6, C3F8,C2F6) used in eye surgery, known and unsubstituted deficiency in vitamin B12 or folic acid, recent and unexplained neurological abnormalities.
* Contraindications to MRI, including claustrophobia.
* Female who is pregnant or breastfeeding or able to procreate without an effective contraceptive method
* Legal incapacity and/or other circumstances rendering the patient unable to understand the nature, purpose or consequences of the study (including major under legal protection).
* A person participating in a drug clinical trial or during a period of exclusion from any clinical study due to previous involvement.
25 Years
50 Years
FEMALE
Yes
Sponsors
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University Hospital, Tours
OTHER
Responsible Party
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Principal Investigators
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Thomas DESMIDT
Role: PRINCIPAL_INVESTIGATOR
CHRU de TOURS
Locations
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University Hospital of Tours
Tours, , France
Countries
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References
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Desmidt T, Dujardin PA, Andersson F, Brizard B, Remenieras JP, Gissot V, Arlicot N, Barantin L, Espitalier F, Belzung C, Tanti A, Robert G, Bulteau S, Gallet Q, Kazour F, Cognet S, Camus V, El-Hage W, Poupin P, Karim HT. Changes in cerebral connectivity and brain tissue pulsations with the antidepressant response to an equimolar mixture of oxygen and nitrous oxide: an MRI and ultrasound study. Mol Psychiatry. 2023 Sep;28(9):3900-3908. doi: 10.1038/s41380-023-02217-6. Epub 2023 Aug 17.
Other Identifiers
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DR190058
Identifier Type: -
Identifier Source: org_study_id