Vagotomy Reduces Insulin Clearance in Obese Mice Programmed by Low-Protein Diet in the Adolescence

Author(s)

Lubaczeuski, Camila ; Goncalves, Luciana Mateus ; Vettorazzi, Jean Franciesco ; Kurauti, Mirian Ayumi ; Santos-Silva, Junia Carolina ; Bonfleur, Maria Lucia ; Boschero, Antonio Carlos ; Costa-Junior, Jose Maria ; Carneiro, Everardo Magalhaes

• Document type: Journal article
• Source: NEURAL PLASTICITY; v. 2017, p. 7-pg., 2017-01-01.

Abstract

The aim of this study was to investigate the effect of subdiaphragmatic vagotomy on insulin sensitivity, secretion, and degradation in metabolic programmed mice, induced by a low-protein diet early in life, followed by exposure to a high-fat diet in adulthood. Weaned 30-day-old C57Bl/6 mice were submitted to a low-protein diet (6% protein). After 4 weeks, the mice were distributed into three groups: LP group, which continued receiving a low-protein diet; LP + HF group, which started to receive a high-fat diet; and LP + HFvag group, which underwent vagotomy and also was kept at a high-fat diet. Glucose-stimulated insulin secretion (GSIS) in isolated islets, ipGTT, ipITT, in vivo insulin clearance, and liver expression of the insulin-degrading enzyme (IDE) was accessed. Vagotomy improved glucose tolerance and reduced insulin secretion but did not alter adiposity and insulin sensitivity in the LP + HFvag, compared with the LP + HF group. Improvement in glucose tolerance was accompanied by increased insulinemia, probably due to a diminished insulin clearance, as judged by the lower C-peptide : insulin ratio, during the ipGTT. Finally, vagotomy also reduced liver IDE expression in this group. In conclusion, when submitted to vagotomy, the metabolic programmed mice showed improved glucose tolerance, associated with an increase of plasma insulin concentration as a result of insulin clearance reduction, a phenomenon probably due to diminished liver IDE expression. (AU)

• FAPESP's process: 13/07607-8 - OCRC - Obesity and Comorbidities Research Center
• Grantee: Licio Augusto Velloso
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 14/01717-9 - Investigation of the insulinotropic, insulinomimetic and endothelial actions of taurine in cells/tissues submitted to an in vitro amino acid restriction: an integrated and multifocal approach
• Grantee: Everardo Magalhães Carneiro
• Support Opportunities: Research Projects - Thematic Grants