Pleasure for Food and Endocannabinoids in Obesity (PLOBEC)

A New Method for the Characterisation of Pleasure for Food in Obesity and Relationships With the Endocannabinoid System

Disturbances in hedonic and motivational processes play a major role in the pathophysiology of obesity. To date, experimental approaches for the study of emotional and motivational processing rely on subjective assessment scales. We have therefore developed two novel computer-generated tasks challenging respectively visual and temporal discrimination capacities for a quantitative and objective measurement of the hedonic and motivational state in humans. According to the task, the subjects are asked to view and to compare two stimuli, an appetitive one (food pictures) and its devalued counterpart (food pictures in greyscale), at each trial, assessing either the size (task A) or the duration of presentation (task B). From these considerations, the present project aims at using our novel tool to: i) assess the hedonic and motivational state in subjects with obesity, ii) compare their responses with healthy volunteers, and iii) establish relationships with biological markers known to be highly involved in the regulation of both emotional and motivational processes, such as endocannabinoids. The present project should demonstrate that the behavioral tests validated in our laboratory are relevant experimental tools for the diagnostic/clinical assessment and for the phenotypic characterization of obese patients. The application of the test in the therapeutic context could add further information about the efficacy and relevance of the chosen therapy. Finally, our project will provide information on the biological substrates of hedonic and motivational impairments that might become target of therapy in obesity.

Study Overview

• Status: Unknown
• Conditions: Obesity
• Intervention / Treatment: Behavioral: Computer-based tasks; Biological: Blood sampling

Detailed Description

Disturbances in hedonic and motivational processes play a major role in the pathophysiology of reward-related diseases, such as obesity. To date, experimental approaches for the study of emotional and motivational processing rely on subjective assessment scales. We have therefore developed and validated a novel computer-generated test challenging visual and temporal discrimination capacities in humans. The subjects are asked to view and to compare two stimuli, an appetitive one (food pictures; F) and its devalued counterpart (food pictures in greyscale; D), at each trial, assessing either the size (task A) or the duration of presentation (task B). Geometric figures are used as controls and presented in color (C) or greyscale (D). Both tasks are registered under the French agency for the protection of computer software. Here, we propose to use our novel test to: i) assess the hedonic and motivational state in subjects suffering from obesity, ii) compare their responses with healthy volunteers, and iii) establish relationships with biological markers known to be highly involved in the regulation of both emotional and motivational processes, such as endocannabinoids. Responses to the test in obese patients will be evaluated during two separate experimental sessions under either fasting or satiety conditions.

The present study is expected to begin mid-November 2013 for a total duration of 24 consecutive months. A sample of 25 patients suffering from obesity will be recruited and compared with 25 healthy normal volunteers who are free from any previous or current metabolic and psychiatric disorders. They will be matched on age and sex. They will be screened using the "Association pour la Méthodologie et la Documentation en Psychiatrie" questionnaire for obtaining a series of information, comprising the marital status, number of children, number of siblings, education and training, professional qualifications, significant life events… They will be evaluated with the Mini-International Neuropsychiatric Interview in order to determine the presence of mood disorders and associated psychopathology. The Three-Factor Eating Questionnaire will be employed for measuring three separate aspects of eating behavior: cognitive restraint, uncontrolled eating, and emotional eating. This will be completed with the Multidimensional Body Self-Relations Questionnaire and the State-Trait Anxiety Inventory in order to assess the body satisfaction and anxiety levels, respectively. Beyond all these assessments, two separate experimental sessions will be conducted, one in satiety and the other in fasting. During each session, the participants will be asked to perform the two validated instrumental tasks in front the screen of a computer. Plasma levels of endocannabinoids will be monitered by collecting blood samples prior to the consumption of a calorically-defined meal and while carrying out the computer-generated tasks under satiety. Blood will be withdrawn at the same time-points during the session in fasting. Visual analogue scales (VAS) assessing hunger levels will be completed before blood is collected. A VAS will be also used for the global assessment of appetitive properties of the viewed food images just before the end of the second experimental session.

• Study Type: Interventional
• Enrollment (Anticipated): 50
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Bruno Aouizerate, Professor; Phone Number: +33 05 57 57 37 06; Email: bruno.aouizerate@u-bordeaux2.fr

Study Locations

• France
  • Bordeaux, France, 33077
    • Recruiting
    • Neurocentre Magendie (INSERM U862)
    • Contact: Bruno Aouizerate, Professor; Phone Number: +33 05 57 57 37 06; Email: bruno.aouizerate@u-bordeaux2.fr
    • Principal Investigator: Bruno Aouizerate, Professor
    • Sub-Investigator: Antoine Tabarin, Professor
    • Sub-Investigator: Blandine Gatta-Cherifi, Professor
    • Sub-Investigator: Camille Gouzien, Doctor

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 60 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

Obese patients :

1. Be between 18 and 60 year-old
2. Have a body mass index ranging from 35 to 50 kg/m2
3. Have no previous history of surgical treatment of obesity
4. Have received no standard intervention for obesity within the last 3 months before study
5. Have a stable weight (variation <5%) within the last 3 months before study
6. Have a restriction score <9 on the three-factor eating questionnaire
7. Be free from any current and previous psychiatric disorder, such as major depression or drug abuse/dependence
8. Understand and accept the design and constraints of the present study
9. Be a beneficiary or member of health insurance plan
10. Provide written consent to the study after receiving clear information

Healthy volunteers :

1. Be between 18 and 60 year-old
2. Be free from any current and previous psychiatric disorder, such as major depression or drug abuse/dependence
3. Understand and accept the design and constraints of the present study
4. Be a beneficiary or member of health insurance plan
5. Provide written consent to the study after receiving clear information

Exclusion Criteria:

Obese patients :

1. Suffer from monogenic obesity
2. Take any psychotropic treatment such as anxiolytic/hypnotic drugs over the last week preceding the study
3. Be a pregnant or nursing woman
4. Use alcohol over the last two days preceding the study

Healthy volunteers :

1. Suffer from any current and previous somatic or psychiatric condition
2. Have a body mass index below 18,5 kg/m2 or above 25 kg/m2
3. Take any psychotropic treatment such as anxiolytic/hypnotic drugs over the last week preceding the study
4. Be a pregnant or nursing woman
5. Use alcohol over the last two days preceding the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Screening
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Obese patients; Computer-based tasks evaluating size and time discrimination capacities Blood sampling for the determination of plasma endocannabinoids levels	Behavioral: Computer-based tasks; Computer-based tasks designed to assess size and time discrimination capacities; Biological: Blood sampling; Blood drawn for the measurement of circulating endocannabinoids concentrations
Experimental: Normal-weight healthy volunteers; Computer-based tasks evaluating size and time discrimination capacities Blood sampling for the determination of plasma endocannabinoids levels	Behavioral: Computer-based tasks; Computer-based tasks designed to assess size and time discrimination capacities; Biological: Blood sampling; Blood drawn for the measurement of circulating endocannabinoids concentrations

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in the Point of subjective equality (PSE)	The PSE is defined as the ratio "F"/"D" or "C"/"D" for which the stimulus "F" or "C" was judged greater than "D" with a probability of 0.5	From fasting to satiety conditions 3 days apart (days 4 and 7 after inclusion)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in the Percentage of subjective discrimination (PSD)	The PSD is defined as the percentage of responses where the stimulus "F" or "C" was judged greater than "D" during the trials where the stimulus "F" or "C" was physically equal to "D", in terms of size or duration of presentation.	From fasting to satiety conditions 3 days apart (days 4 and 7 after inclusion)
Circulating endocannabinoids concentrations		Determined on blood samples collected during the experimental sessions under fasting and satiety (days 4 and 7 after inclusion)

Collaborators and Investigators

• Sponsor: Institut National de la Santé Et de la Recherche Médicale, France
• Investigators: Principal Investigator: Bruno Aouizerate, Professor, Neurocentre Magendie (INSERM U862)

Study record dates

Study Major Dates

• Study Start: January 1, 2014
• Primary Completion (Anticipated): February 1, 2016
• Study Completion (Anticipated): February 1, 2016

Study Registration Dates

• First Submitted: November 4, 2013
• First Submitted That Met QC Criteria: November 8, 2013
• First Posted (Estimate): November 15, 2013

Study Record Updates

• Last Update Posted (Estimate): February 24, 2016
• Last Update Submitted That Met QC Criteria: February 23, 2016
• Last Verified: February 1, 2016

More Information

Terms related to this study

• Keywords: Obesity, food pleasure, behavioral tasks, endocannabinoids
• Additional Relevant MeSH Terms: Overnutrition; Nutrition Disorders; Overweight; Body Weight; Obesity
• Other Study ID Numbers: C13-33; 2013-A00982-43 (Registry Identifier: IDRCB)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No