Le tractus digestif comme organe endocrine : une nouvelle vision de la chirurgie bariatrique

Bariatric surgery has proven its efficacy to obtain a marked and sustained weight loss and dramatically improve metabolic control in obese patients with type 2 diabetes. The frequently observed remission of diabetes occurs very early, before any significant weight reduction. Increasing evidence suggests that this favourable effect results from profound changes in gut hormones involved in the regulation of energy intake behaviour and glucose homeostasis rather than simply from mechanical food restriction or malabsorption imposed by the surgical procedure. These hormonal changes result from partial stomach amputation (leading to reduced ghrelin secretion), from bypass of duodenal-jejunal foregut (leading to reduced secretion of still unknown factors that may counteract insulin secretion and/or action) and from an earlier contact of food with hindgut (leading to enhanced secretion of incretin hormones such as glucagon-like peptide-1 [GLP-1] by the ileal L cells, neuropeptide YY and oxyntomodulin). The better knowledge of these pathophysiological mechanisms, especially well studied withRoux-en Ygastric bypass, resulted in recent innovation in the technical procedures leading to a shift from bariatric surgery to metabolic surgery.