Selective Vagotomy Worsens Glucose Control After Ileal Transposition

Area of Science:

• Endocrinology
• Gastroenterology
• Surgical Research

Background:

• Ileal transposition (IT) is a surgical procedure investigated for its potential to improve glycemic control in diabetes.
• The role of the vagus nerve in metabolic regulation and its interaction with gastrointestinal surgeries is not fully understood.

Purpose of the Study:

• To investigate the impact of selective celiac branch vagotomy on food intake and glycemic control in diabetic rats that underwent ileal transposition (IT).
• To explore the potential role of the vagus nerve in mediating the diabetes-improving effects of IT.

Main Methods:

• Forty non-obese diabetic rats underwent either IT, IT + celiac branch vagotomy (ITV), sham IT (SI), or sham IT + celiac branch vagotomy (SIV).
• Animals were pair-fed, and measurements included food intake, body weight, fasting plasma glucose, and glucagon-like peptide 1 (GLP-1) levels.
• Post-sacrifice analysis involved quantifying activated pro-opiomelanocortin (POMC) neurons and POMC-derived peptides.

Main Results:

• The ITV group exhibited higher fasting glucose levels and a greater area under the curve for oral glucose tolerance tests compared to the IT group.
• No significant difference in postprandial GLP-1 levels was observed between ITV and IT groups.
• The ITV group showed a reduced number of activated POMC neurons and lower levels of POMC-derived peptides compared to the IT group.

Conclusions:

• Celiac branch vagotomy appears to diminish the beneficial effects of ileal transposition on glycemic control and may reduce food intake.
• These findings suggest that the vagus nerve, specifically its celiac branches, might contribute to the improvements in diabetes observed after IT.
• Modulating vagal activity could represent a potential therapeutic strategy for managing diabetes.