Normalizing weight gain and preventing the redistribution of body fat is a major health issue, and could help prevent the onset of various symptoms of metabolic syndrome. Above all, it is important to understand the mechanisms by which these different treatments affect adipose tissue. To this end, the investigators will first study the impact of GLP-1 analogues on adipose tissue. The main objective is to show that subjects treated with a GLP-1 agonist have a significant change in their oxytocin levels compared with subjects not treated with a GLP-1 agonist.

Inclusion Criteria:

• Patient over 18 years of age.
• Patient able to read and understand the information/consent leaflet.
• Patient with BMI > 35 with at least one comorbidity. Or BMI > 40
• Indication for digestive surgery validated in a multidisciplinary consultation meeting and prior agreement accepted by the CPAM.
• Membership of a social security scheme
• Patient's signed informed consent
• For subjects in the GLP-1 analogue group: GLP-1 analogue taken for at least 3 months.
• For non-GLP-1 analogue group: never taken GLP-1 analogues.

Exclusion Criteria:

• Pregnant or breast-feeding women.
• Vulnerable patients (under guardianship)
• Patients deprived of liberty