Impaired Gustatory Sensory Perception in Obese and Obese Diabetic Persons

Study Overview
=================
Brief Summary
-----------------
The aim of the study is to compare several parameters in three distinct groups of subjects: persons with obesity, persons with obesity and diabetes and persons with neither obesity nor diabetes: the electrical activity in response to a sweet solution, measured before and after a standard meal, using gustatory evoked potentials (recording explained below) blood hormone levels related to weight gain (insulin, dopamine, ghrelin, leptin: measured in blood samples) levels of activity and quantity of an enzyme present in the saliva, amylase, which is able to break down ingested starch into several molecules of glucose. All of these parameters will be correlated to determine whether the results are different in the 3 groups of subjects in the study.

Official Title
-----------------
Gustatory Evoked Potentials and Cerebral Control of Food Intake in Obese Subjects

Conditions
-----------------
Obesity, Diabetes

Intervention / Treatment
-----------------
* Other: Recording of GEP (Gustatory Evoked Potentials)


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients who have provided written consent Patients over 18 years old Body Mass Index (BMI) <25 kg/m² for healthy volunteers and BMI≥30 kg/m² for obese subjects Patients with type 2 diabetes for the group obese diabetic subjects Exclusion Criteria: Patients under guardianship Patients without health insurance cover Pregnant or breast-feeding women Active smokers Subjects with type 2 diabetes for the  healthy subjects  and  obese subjects , subjects with type 1 diabetes for all groups Subjects who do not speak French Treatment that interferes with taste or acts on the central nervous system Anti-diabetic treatment with GLP-1 analogues (Glucagon-like peptide 1) or SGLT2 (sodium-glucose cotransporter type 2) Known hypersensitivity to the foods proposed in the study, or the paste used to fix the electrodes, or to paraffin wax or to the products tested (sucrose, glucose or starch for the gustatory evoked potentials and triangular tests)

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Other
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: healthy subjects<br> | Other: Recording of GEP (Gustatory Evoked Potentials)<br>* record cerebral activity thanks to electrodes placed on the head and fixed with a painless, harmless adhesive paste and linked to a computer equipped with specific software to interpret the signals obtained. The collection of data for the electric signal takes 20 minutes.<br>|
| Experimental: obese<br> | Other: Recording of GEP (Gustatory Evoked Potentials)<br>* record cerebral activity thanks to electrodes placed on the head and fixed with a painless, harmless adhesive paste and linked to a computer equipped with specific software to interpret the signals obtained. The collection of data for the electric signal takes 20 minutes.<br>|
| Experimental: obese diabetic<br> | Other: Recording of GEP (Gustatory Evoked Potentials)<br>* record cerebral activity thanks to electrodes placed on the head and fixed with a painless, harmless adhesive paste and linked to a computer equipped with specific software to interpret the signals obtained. The collection of data for the electric signal takes 20 minutes.<br>|
| Experimental: obese diabetic who are going to be operated on<br>25 of a sleeve gastrectomy and 25 of a Y gastric bypass | Other: Recording of GEP (Gustatory Evoked Potentials)<br>* record cerebral activity thanks to electrodes placed on the head and fixed with a painless, harmless adhesive paste and linked to a computer equipped with specific software to interpret the signals obtained. The collection of data for the electric signal takes 20 minutes.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Amplitude of the gustatory evoked potential |  | Up to 10 days | 
| Latency of the gustatory evoked potential |  | Up to 10 days |