Is a Simple Food-Diverting Operation the Solution for Type 2 Diabetes Treatment? Experimental Study in a Non-Obese Rat Model

Proximal small intestinal bypass outperforms Roux-en-Y and jejunoileal bypass in glucose regulation in streptozotocin induced diabetic rats

BACKGROUND

The efficacy of various bariatric surgeries varies in reducing blood glucose levels. Given the distinct mechanisms and anatomical alterations associated with each procedure, it is crucial to compare their glycemic control outcomes. We hypothesize that proximal small intestinal bypass (PSIB) is superior in blood glucose reduction over Roux-en-Y gastric bypass (RYGB) and jejunoileal bypass (JIB).

AIM

To compare the effectiveness of PSIB, RYGB, and JIB in lowering blood glucose.

METHODS

Rats with streptozotocin-induced diabetes were randomly divided into PSIB, RYGB, JIB, and sham-operated groups. Body weight, food intake, fasting blood glucose level, oral glucose tolerance test, insulin tolerance test, liver enzymes, and blood lipids were measured.

RESULTS

Postoperatively, only the JIB group had a lower body weight compared to the sham group. The food intake of the rats in all three surgical groups was significantly less than that in the sham group. Fasting blood glucose was reduced in all surgical groups and was lower in the PSIB group than in the RYGB and JIB groups. Glucose tolerance and insulin sensitivity improved in all three surgical groups compared to the sham group, but the improvement appeared earliest in the PSIB group. At six weeks post-surgery, the PSIB group showed a reduction in alanine transaminase levels and maintained a normal lipid profile.

CONCLUSION

PSIB demonstrated excellent hypoglycemic effects in the early postoperative period, and had better efficacy than RYGB and JIB.

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.

Rapid Improvement in Diabetes After Simple Side-to-side Jejunoileal Bypass Surgery: Does It Need a Ligation or Not?

BACKGROUND

Dual-path side-to-side jejunoileal bypass (SSJIB) can markedly ameliorate diabetes and obesity. However, whether SSJIB requires the ligation of the bypassed loop (single-path) and what is the most appropriate length of the bypassed small bowel remain unknown. The aim of this study was to evaluate the role of ligation and the length of the bypassed small bowel in mediating changes in glucose homeostasis after SSJIB in streptozotocin (STZ)-induced diabetic rats.

METHODS

Fourteen STZ-induced diabetic rats were randomized into two groups: one group was subjected to 50% SSJIB (SSJIB-50 group) and one group was subjected to sham surgery (sham group). Three weeks later, the SSJIB-50 group was re-operated, and the bypassed segment was ligated (SSJIBL-50 group). Three weeks later, the SSJIBL-50 group was operated again, and 60% of the length of the proximal small intestine was bypassed (SSJIBL-60 group). The measured primary outcomes were body weight, food intake, fasting blood glucose (FBG), and oral glucose tolerance test (OGTT).

RESULTS

Body weight in the SSJIBL-60 group was lower than that in the sham group. Food intakes in the SSJIBL-50 and SSJIBL-60 groups were lower than that in the sham group. FBG and OGTT were not improved in the SSJIB-50 group compared with the sham group. However, FBG and OGTT were improved in the SSJIBL-50 group and were further improved in the SSJIBL-60 group.

CONCLUSIONS

Ligation of the first portion of the bypassed loop is essential to SSJIB, and bypassing approximately 60% of the small intestine length may be appropriate in SSJIBL.

Partial jejunal diversion using an incisionless magnetic anastomosis system: 1-year interim results in patients with obesity and diabetes

BACKGROUND AND AIMS

Most patients with type 2 diabetes mellitus have obesity. Studies show that bariatric surgery is superior to medical treatment for remission of type 2 diabetes mellitus. Nevertheless, very few patients undergo surgery, and a less-invasive endoscopic alternative is desirable.

METHODS

This was a single-arm first-in-human pilot study designed to evaluate the technical feasibility, safety, and clinical performance of the incisionless magnetic anastomosis system (IMAS) to create a partial jejunal diversion (PJD). Ten patients with obesity and type 2 diabetes mellitus, prediabetes, or no diabetes were enrolled. A PJD to the ileum was attempted in all patients under general anesthesia. The IMAS was delivered through the working channel of a colonoscope, with laparoscopic supervision. The patients were not required to participate in an intensive lifestyle/diet management program. Endoscopic visualization of the anastomosis was obtained at 2, 6, and 12 months. Patient weight, glycemic profile, and metabolic panels were acquired at 0.5, 1, 2, 3, 6, 9, and 12 months.

RESULTS

A PJD was created in all patients with no device-related serious adverse events. The anastomosis remained widely patent in all patients at 1 year. Average total weight loss was 14.6% (40.2% excess weight loss at 12 months). A significant reduction in glycated hemoglobin level was observed in all diabetic (1.9%) and prediabetic (1.0%) patients, while reducing or eliminating the use of diabetes medications.

CONCLUSIONS

Permanent anastomosis for PJD was created in all patients with the IMAS. This resulted in improvement in measures of hyperglycemia and progressive weight loss. (Clinical trial registration number: NCT02839512.).