Sleeve Gastrectomy, GLP-1 Secretion and Gastric Emptying

A prospective study titled “The effect of sleeve gastrectomy on GLP-1 secretion and gastric emptying” has recently been published in SOARD (Surgery for Obesity and Related Disorders) journal. Sista el al demonstrate that gastric sleeve surgery results in significant increase in both gastric emptying rate and post-prandial GLP-1 secretion, 3 months after surgery for both solids and liquids.

The authors attribute the increased gastric emptying following sleeve gastrectomy to altered stomach functional anatomy and gastric fundus accommodation reflex. Furthermore, they show a strong linear correlation between percentage gastric retention rate and post-prandial GLP-1 blood levels. The authors conclude that accelerated gastric emptying following gastric sleeve surgery increases GLP-1 secretion by distal intestinal L cells most likely by increasing undigested nutrient transit across the small intestine. Chronic exposure to a high nutrient flux into the intestine enhances intestinal nutrient sensing leading to increased GLP-1 secretion.

Indeed, the central mechanism of action of metabolic and weight loss surgery is altering the interaction between ingested food and gastro-intestinal tract. Altered interaction results in the secretion of several neuro-endocrine signals like GLP-1 that results in weight loss, improved blood glucose levels, insulin secretion and insulin resistance…

Unfortunately, research in this field remains weak. Most bariatric related research and publications are still focused on the outdated concept of mechanical restriction. New procedures like gastric balloon and gastric plication (endoscopic or laparoscopic) are developed and offered as effective weight loss solutions.

Gastrointestinal motility research is vital in elucidating the mechanism of action of bariatric surgery. Gastroparesis, GERD, type 2 diabetes and obesity are different kinds of gastro-intestinal motility disorders. Unraveling the mechanisms of gastro-intestinal motility in health and disease will yield great solutions to these disorders that have reached epidemic levels.