Influence of sleeve gastrectomy on several experimental models of obesity: metabolic and hormonal implications

Abstract

Background: Ghrelin is an important factor in the regulation of intake. Most ghrelin is synthesized in the gastric fundus, but this is not the only location. The aim of this experimental study was to analyze the effect of sleeve gastrectomy (removing fundus) on the volume of intake in four experimental models and determine how this relates to changes in weight, plasmatic levels of glycemia, ghrelin, GLP-1, and insulin.

Methods: Sleeve gastrectomy was performed on four experimental models: (1) non-obesity; (2) exogenous obesity caused by excessive calorie intake; (3) genetically determined obesity (Zucker rats); and (4) genetically determined obesity and type 2 diabetes mellitus (Zucker diabetic fatty; ZDF rats). Model 2 had a control group on which sleeve gastrectomy was not performed.

Results: In the non-obese group, there were few changes after intervention, but in model 2, sleeve gastrectomy led to normalization of weight and endocrine-metabolic parameters that were the same as those for non-obese rats. The exception was for GLP-1, which has an anorexigenic effect: GLP-1 remained higher. In Zucker rats, sleeve gastrectomy had a slight effect on all parameters. In ZDF rats, sleeve gastrectomy led to a reduction in intake and a stabilization of weight.

Conclusions: Sleeve gastrectomy is a very good option for exogenous obesity. Normalization of hormonal levels led us to find an extragastric ghrelin production.