The Effect of Gastric Bypass with a Distal Gastric Pouch on Glucose Tolerance and Diabetes Remission in Type 2 Diabetes Sprague-Dawley Rat Model

Outcomes and complications after long versus short gastric pouch Roux-en-Y gastric bypass in patients with severe obesity

Roux-en-Y gastric bypass (RYGB) is the second most common metabolic and bariatric surgery (MBS) globally. The impact of pouch size on weight loss outcomes and complications remains unclear. This study aims to compare the weight loss outcomes and complications in long pouch versus short pouch RYGB in patients with severe obesity. This retrospective study, conducted in 2021 in two academic tertiary Hospitals, included patients aged 18-65 with severe obesity who underwent RYGB with two different methods. Demographic data, past medical history, and surgical details were assessed. The study outcome was postoperative metrics at 12 months including weight loss outcomes and complications like marginal ulceration, and leaks. A total of 219 patients, who were included in this study, were divided into two groups: 107 with long gastric pouches and 112 with short gastric pouches. The average age was 41.33 ± 10.26 and 42.45 ± 11.70 in long and short gastric pouches, respectively. Patients with long gastric pouches had a mean weight of 113.29 ± 16.52 kg and mean Body Mass Index (BMI) of 42.97 ± 4.15 kg/m2, and patients with short gastric pouches had a mean weight of 118.39 ± 12.80 kg and mean BMI of 45.21 ± 5.10 kg/m2. At 12 months after surgery, substantial weight loss was noted in all participants (37.8 ± 10.7 kg in patients with long gastric pouch; 48.1 ± 11.3 kg in patients with short gastric pouch; P = 0.033). Delta BMI (P = 0.072), and TWL% (P = 0.061), were more pronounced in patients with short pouches, however the difference was not significant. Remission of underlying diseases and endoscopic findings were comparable for short and long gastric pouch groups. Both long and short-pouch gastric bypass surgeries are effective and safe for weight loss and remission of obesity-associated medical problems in patients with severe obesity and exhibited similar rates for remission of underlying diseases and endoscopic findings. More studies are needed to individualize surgical approaches based on patient characteristics.

Effects of subtotal pancreatectomy and long-term glucose and lipid overload on insulin secretion and glucose homeostasis in minipigs

INTRODUCTION

Nowadays, there are no strong diabetic pig models, yet they are required for various types of diabetes research. Using cutting-edge techniques, we attempted to develop a type 2 diabetic minipig model in this study by combining a partial pancreatectomy (Px) with an energetic overload administered either orally or parenterally.

METHODS

Different groups of minipigs, including Göttingen-like (GL, n = 17) and Ossabaw (O, n = 4), were developed. Prior to and following each intervention, metabolic assessments were conducted. First, the metabolic responses of the Göttingen-like (n = 3) and Ossabaw (n = 4) strains to a 2-month High-Fat, High-Sucrose diet (HFHSD) were compared. Then, other groups of GL minipigs were established: with a single Px (n = 10), a Px combined with a 2-month HFHSD (n = 6), and long-term intraportal glucose and lipid infusions that were either preceded by a Px (n = 4) or not (n = 4).

RESULTS

After the 2-month HFHSD, there was no discernible change between the GL and O minipigs. The pancreatectomized group in GL minipigs showed a significantly lower Acute Insulin Response (AIR) (18.3 ± 10.0 IU/mL after Px vs. 34.9 ± 13.7 IU/mL before, p < .0005). In both long-term intraportal infusion groups, an increase in the Insulinogenic (IGI) and Hepatic Insulin Resistance Indexes (HIRI) was found with a decrease in the AIR, especially in the pancreatectomized group (IGI: 4.2 ± 1.9 after vs. 1.5 ± 0.8 before, p < .05; HIRI (×10^-5 ): 12.6 ± 7.9 after vs. 3.8 ± 4.3 before, p < .05; AIR: 24.4 ± 13.7 µIU/mL after vs. 43.9 ± 14.5 µIU/mL before, p < .005). Regardless of the group, there was no fasting hyperglycemia.

CONCLUSIONS

In this study, we used pancreatectomy followed by long-term intraportal glucose and lipid infusions to develop an original minipig model with metabolic syndrome and early signs of glucose intolerance. We reaffirm the pig's usefulness as a preclinical model for the metabolic syndrome but without the fasting hyperglycemia that characterizes diabetes mellitus.

Effect of sleeve gastrectomy, Roux-en-Y gastric bypass, and ileal transposition on myocardial ischaemia-reperfusion injury in non-obese non-diabetic rats

Bariatric surgery (BS) improves outcomes in patients with myocardial infarction (MI). Here we tested the hypothesis that BS-mediated reduction in fatal MI could be attributed to its infarct-limiting effect. Wistar rats were randomized into five groups: control (CON), sham (SHAM), Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and ileotransposition (IT). Ten weeks later, animals were subjected to 30-min myocardial ischemia plus 120-min reperfusion. Infarct size (IS) and no-reflow area were determined histochemically. Fasting plasma levels of glucagon-like peptide-1 (GLP-1), leptin, ghrelin, and insulin were measured using ELISA. Compared with SHAM, RYGB and SG reduced IS by 22% (p = 0.011) and 10% (p = 0.027), and no-reflow by 38% (p = 0.01) and 32% (p = 0.004), respectively. IT failed to reduce IS and no-reflow. GLP-1 level was increased in the SG and RYGB groups compared with CON. In both the SG and RYGB, leptin level was decreased compared with CON and SHAM. In the SG group, ghrelin level was lower than that in the CON and SHAM. Insulin levels were not different between groups. In conclusion, RYGB and SG increased myocardial tolerance to ischemia-reperfusion injury of non-obese, non-diabetic rats, and their infarct-limiting effect is associated with decreased leptin and ghrelin levels and increased GLP-1 level.

Revisional large gastric pouch with Roux-en-Y gastric bypass for patients with type 2 diabetes and a body mass index less than 35 kg/m2: a cause and effect analysis

PURPOSE

To evaluate the long-term efficacy of large gastric pouch surgery and revisional surgery in patients with a body mass index (BMI) < 35 kg/m² and type 2 diabetes mellitus (T2DM).

METHODS

We conducted a retrospective review of patients who underwent laparoscopic Roux-en-Y gastrojejunostomy with a large gastric pouch in our hospital. The clinical pre- and post-surgery data, including BMI, waist circumference, fasting plasma glucose (FPG), glycated hemoglobin (HbA1c), lipid metabolism-related indicators, homoeostatic model assessment of insulin resistance (HOMA-IR), and major complications, were recorded and analyzed.

RESULTS

Twenty-four patients were included in the analysis, 12 of whom underwent revisional surgery. At their 5-year-follow-up after the primary surgery, the BMI and waist circumference of the patients with T2DM were lower than their baseline values. The BMI, HbA1c, HOMA-IR, FPG and waist circumference also decreased after the revisional surgery. The rates of remission of diabetes after the primary vs. after the revisional surgery were 4.17% vs. 41.70%, respectively (P < 0.05).

CONCLUSION

Roux-en-Y gastrojejunostomy with a large gastric pouch is not effective in the long term and, therefore, is unsuitable for Chinese patients with T2DM and a BMI < 35 kg/m². Conversely, revisional surgery has a definite effect on these patients.

Effects of three types of bariatric interventions on myocardial infarct size and vascular function in rats with type 2 diabetes mellitus

AIMS

The effects of three types of bariatric interventions on myocardial infarct size were tested in the rat model of type 2 diabetes mellitus (T2DM). We also evaluated the effects of bariatric surgery on no-reflow phenomenon and vascular dysfunction caused by T2DM.

MAIN METHODS

Rats with T2DM were assigned into groups: without surgery, sham-operated, ileal transposition, Roux-en-Y gastric bypass, and sleeve gastrectomy. Oral glucose tolerance, glucagon-like peptide-1, and insulin levels were measured. Six weeks after surgery, the animals were subjected to myocardial ischemia-reperfusion followed by histochemical determination of infarct size (IS), no-reflow zone, and blood stasis area size. Vascular dysfunction was characterized using wire myography.

KEY FINDINGS

All bariatric surgery types caused significant reductions in animal body weight and resulted in T2DM compensation. All bariatric interventions partially normalized glucagon-like peptide-1 responses attenuated by T2DM. IS was significantly smaller in animals with T2DM. Bariatric surgery provided no additional IS limitation compared with T2DM alone. Bariatric surgeries reversed T2DM-induced enhanced contractile responses of the mesenteric artery to 5-hydroxytryptamine. Sleeve gastrectomy normalized decreased nitric oxide synthase contribution to the endothelium-dependent vasodilatation in T2DM.

SIGNIFICANCE

T2DM resulted in a reduction of infarct size and no-reflow zone size. Bariatric surgery provided no additional infarct-limiting effect, but it normalized T2DM-induced augmented vascular contractility and reversed decreased contribution of nitric oxide to endothelium-dependent vasodilatation typical of T2DM. All taken together, we suggest that this type of surgery may have a beneficial effect on T2DM-induced cardiovascular diseases.

Distal gastric mucosa ablation induces significant weight loss and improved glycemic control in type 2 diabetes Sprague-Dawley rat model

BACKGROUND

Excluding the foregut (distal stomach and duodenum) from food transit in RYGB normalizes glucose tolerance. Excluding/removing the duodenal mucosa partly improves glycemic control. So far, the effect of excluding/removing the gastric mucosa remains unknown.

OBJECTIVE

To observe the effect of removing the distal gastric mucosa on glucose tolerance.

METHOD

Thirty fatty Sprague-Dawley rats received low-dose streptozotocin (STZ) to induce type 2 diabetes (T2D), then randomly assigned to Roux-en-Y gastric bypass (RYGB, n = 8), distal gastric mucosa removal (DGMR, n = 8), duodenal-jejunal bypass (DJB, n = 8), and Sham (n = 6) groups. In the DGMR group, the distal third of the gastric mucosa was removed by thermal ablation using an electrocautery. Rats were followed for 8 weeks postoperatively. Preoperative oral glucose tolerance test (OGTT), insulin tolerance test (ITT), and mixed-meal tolerance test (MMTT) were repeated 3 and 6 weeks postoperatively. Changes in body weight, food intake, and fasting blood glucose were also recorded.

RESULTS

Gastrin AUC decreased significantly (p < 0.05) in the DGMR group after surgery. A significantly increased GLP-1 AUC was found in the RYGB, DGMR, and DJB groups at week 3 and only the RYGB group at week 6 postoperatively. The improved glucose tolerance in the RYGB group was significantly greater than the improved glucose tolerance in the DGMR and DJB groups. The improved glucose tolerance 3 and 6 weeks after surgery in the DGMR group was significantly greater than the improved glucose tolerance in the DJB group. Body weight decreased significantly in the RYGB, DGMR, and DJB groups postoperatively.

CONCLUSION

Removing the distal gastric mucosa induced significant weight loss and improved glycemic control in T2D SD rat model. Therefore, the gastric mucosa exclusion in RYGB may be key to the weight loss and diabetes remission, which perhaps warrants a new theory.