A rodent model of partial intestinal diversion: a novel metabolic operation.

BACKGROUND: Metabolic surgery is safe and the most effective therapy for obesity and its co-morbidities. New procedures may allow for better tailoring of metabolic surgery to the individual patient.

OBJECTIVE: To evaluate the impact, comparative effectiveness, and mechanisms of the partial intestinal diversion (PID), vertical sleeve gastrectomy (VSG), and the combination of PID and VSG on weight and glucose regulation.

SETTING: University research facility, United States.

METHODS: Three cohorts of high-fat diet-induced obese male rats were randomized to distal PID (DPID), proximal PID (PPID), VSG, VSG and DPID (VSG/DPID), or sham operation (Sham). Animals were followed for 11 (cohort 1) or 10 (cohorts 2 and 3) weeks. Outcomes included weight and composition, food intake, glucose metabolism, lipids, bile acids, and energy balance. Statistical comparisons were performed using Tukey's multiple comparison test applied to analysis of variance.

RESULTS: DPID and not PPID resulted in significant weight and body fat reductions relative to Sham. Improved glucose tolerance was seen in all surgical groups though this reached statistical significance for only DPID and VSG compared with Sham. Improvements in baseline glucose and insulin, corresponding insulin resistance, and plasma lipids were noted in DPID compared with Sham. Though the magnitude of weight and body composition changes and metabolic benefit tended to be larger for VSG relative to DPID, it only reached statistical significance for lipids. VSG and VSG/DPID resulted in similar outcomes. Markedly reduced food intake occurred after VSG and more modestly after DPID. Stool caloric content was higher in DPID relative to all groups.

CONCLUSIONS: DPID is an effective metabolic operation resulting in notable weight and fat loss and metabolic improvement relative to sham-operated rodents. Interestingly, combining VSG with DPID added little additional benefit to the effects of VSG.