First Evaluation of Roux-en-Y Gastric Bypass as a Novel Surgical Treatment for Diabetes and Glucose Metabolism Regulation in Cats

Objective: To evaluate the efficacy of Roux-en-Y gastric bypass (RYGB) in improving glucose regulation and metabolic parameters in feline diabetes mellitus (FDM). Methods: FDM was experimentally induced via partial pancreatectomy, splenectomy, and dexamethasone administration. Following insulin stabilization, the RYGB cohort underwent gastric bypass, while the medical management group received glargine insulin. Untreated diabetic controls were monitored for 12 weeks. Blood glucose (GLU), fructosamine (FRU), biochemical profiles, and metabolic hormones were evaluated pre- and post-intervention. Hepatic and pancreatic tissues were collected for histopathological examination. Results: GLU and FRU concentrations in the RYGB group were significantly lower than in diabetic controls (p < 0.05), remaining comparable to the insulin-treated group (p > 0.05). Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were significantly reduced post-RYGB (p < 0.05), closely matching insulin therapy outcomes (p > 0.05). Hormonal assays demonstrated decreased gastric inhibitory polypeptide (GIP) and elevated glucagon-like peptide-1 (GLP-1) in RYGB cats. Histopathologically, the RYGB group exhibited attenuated hepatic steatosis and a higher density of pancreatic islet cells with abundant cytoplasm compared to the control groups. Conclusions: RYGB effectively restores glycemic control and metabolic hormone balance in FDM, promoting morphological improvements in pancreatic islets and offering a highly promising alternative therapy for diabetic felines.