The proposed project is a descriptive cross-sectional pathophysiological study .The aims are 1) to better define the process of senescence in human adipose tissue, 2) to precise the mechanisms and 3) to analyse the cellular and functional consequences of aging on inflammation, adipose tissue development and metabolism. 200 morbidly obese candidates for bariatric surgery will be studied. The collection of clinical and laboratory data and the collection of biological samples (plasma, blood cells and subcutaneous and visceral adipose tissues) will be made at the inclusion and during surgery (obesity center, Hôpital Louis Mourier). Analyses of adipose tissue will be performed at INSERM U1048 and will focus on in vitro approaches of the cells of the adipose tissues (mature adipocytes, endothelial cells, progenitor cells and immuno-inflammatory cells).