Sleeve gastrectomy leads to weight loss in the Magel2 knockout mouse.

backgroundPrader-Willi syndrome (PWS) is a genetic disorder characterized by hyperphagia, obesity, cardiopulmonary diseases, and increased mortality. Although successful weight loss improves health in PWS, few treatments cause sustained weight loss in obese patients let alone obese individuals with PWS.

objectivesThe present study uses the Magel2 knockout (KO) mouse, an animal model of PWS, to conduct a preclinical study on the efficacy of sleeve gastrectomy (SG) in PWS.

settingAcademic research laboratory, United States.

methodsWe performed sham or SG surgeries in 24- to 28-week-old male Magel2 KO and wild-type littermate control mice (WT) who had been maintained on a high-fat diet for 10 weeks. We monitored weight, food intake, and fat and lean mass pre- and postoperatively. Fasting glucose, glucose tolerance, and counter-regulation were measured postoperatively.

resultsMagel2 KO animals had similar recovery and mortality rates compared with WT. SG resulted in similar weight loss, specifically loss of fat but not lean mass, in both Magel2 KO and WT mice. SG also resulted in significantly lower fasting glucose levels and a reduction in fat intake in both Magel2 KO and WT mice. We also found that Magel2 KO mice failed to increase their food intake in response to the glucoprivic agent 2-deoxy-D-glucose, suggesting impaired glucose counter-regulation, but this occurred regardless of surgical status. All results were considered significant when P< .05.

conclusionWe find in this mouse model of PWS, SG is a well-tolerated, effective strategy for weight and fat loss.