Basic Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 21, 2017; 23(35): 6403-6411
Published online Sep 21, 2017. doi: 10.3748/wjg.v23.i35.6403
Pharmacological inhibition of cannabinoid receptor 1 stimulates gastric release of nesfatin-1 via the mTOR pathway
Cintia Folgueira, Silvia Barja-Fernandez, Laura Prado, Omar Al-Massadi, Cecilia Castelao, Veronica Pena-Leon, Patricia Gonzalez-Saenz, Javier Baltar, Ivan Baamonde, Rosaura Leis, Carlos Dieguez, Uberto Pagotto, Felipe F Casanueva, Sulay A Tovar, Ruben Nogueiras, Luisa M Seoane
Cintia Folgueira, Silvia Barja-Fernandez, Laura Prado, Cecilia Castelao, Veronica Pena-Leon, Patricia Gonzalez-Saenz, Ivan Baamonde, Luisa M Seoane, Grupo Fisiopatología Endocrina, Instituto de Investigación Sanitaria de Santiago de Compostela, 15706 Santiago de Compostela, Spain
Cintia Folgueira, Silvia Barja-Fernandez, Omar Al-Massadi, Cecilia Castelao, Patricia Gonzalez-Saenz, Rosaura Leis, Carlos Dieguez, Felipe F Casanueva, Sulay A Tovar, Ruben Nogueiras, Luisa M Seoane, CIBER Fisiopatología Obesidad y Nutrición, Instituto de Salud Carlos III, 15782 Santiago de compostela, Spain
Cintia Folgueira, Omar Al-Massadi, Carlos Dieguez, Sulay A Tovar, Ruben Nogueiras, Department of Physiology, Research Centre of Molecular Medicine and Chronic Diseases, 15782 Santiago de Compostela, Spain
Silvia Barja-Fernandez, Rosaura Leis, Department of Pediatric, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
Javier Baltar, Ivan Baamonde, Servicio de Cirugía General, Complexo Hospitalario Universitario de Santiago, 15706 Santiago de Compostela, Spain
Uberto Pagotto, Endocrinology Unit and Center for Applied Biomedical Research, Department of Medical and Surgical Sciences, Hospital S. Orsola-Malpighi, Alma Mater University of Bologna, 40126 Bologna, Italy
Felipe F Casanueva, Laboratorio de Endocrinología Molecular y Celular. Universidad de Santiago de Compostela, Instituto de Investigación Sanitaria de Santiago de Compostela, Complexo Hospitalario Universitario de Santiago, 15706 Santiago de Compostela, Spain
Author contributions: Baltar J, Baamonde I, Leis R, Dieguez C, Casanueva FF, Tovar SA, Nogueiras R and Seoane LM substantially contributed to the conception and design of the study, acquisition, analysis and interpretation of data; Folgueira C, Barja-Fernandez S, Prado L, Al-Massadi O, Castelao C, Pena-Leon V and Gonzalez-Saenz P contributed to the experimental protocols, animal models development and data acquisition and analysis; all authors drafted the article and made critical revisions related to the intellectual content of the manuscript, and approved the final version of the article to be published; Folgueira C and Barja-Fernandez S contributed equally to this work.
Supported by Instituto de Salud Carlos III, No. PI15/01272 cofounded by FEDER; Fondo de Investigaciones Sanitarias (LS: I3SNS-SERGAS/ISCIII). Centro de Investigacion Biomedica en Red Fisiopatología de la Obesidad y Nutrición (CIBERobn) is a iniciative of the Instituto de Salud Carlos III (ISCIII) of Spain which is supported by FEDER funds.
Institutional review board statement: The study was reviewed and approved by the “Comité Etico de Investigación Clinica de Galicia”.
Institutional animal care and use committee statement: The approaches in the present manuscript were performed under the procedure 15005/2015/003 reviewed and approved by the Faculty Animal Committee at the University of Santiago de Compostela.
Conflict-of-interest statement: To the best of our knowledge, no conflict of interest exists.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Luisa M Seoane, PhD, Grupo Fisio-patología Endocrina, Laboratorio 14, Instituto de Investigación Sanitaria, Complexo Hospitalario Universitario de Santiago, Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain. luisamaria.seoane@usc.es
Telephone: +34-981-955450 Fax: +34-981-956189
Received: April 19, 2017
Peer-review started: April 21, 2017
First decision: July 28, 2017
Revised: July 31, 2017
Accepted: August 25, 2017
Article in press: August 25, 2017
Published online: September 21, 2017
Abstract
AIM

To determine whether Nucb2/nesfatin1 production is regulated by the cannabinoid system through the intracellular mTOR pathway in the stomach.

METHODS

Sprague Dawley rats were treated with vehicle, rimonabant, rapamycin or rapamycin+rimonabant. Gastric tissue obtained from the animals was used for biochemical assays: Nucb2 mRNA measurement by real time PCR, gastric Nucb2/nesfatin protein content by western blot, and gastric explants to obtain gastric secretomes. Nucb2/nesfatin levels were measured in gastric secretomes and plasma using enzyme-linked immunosorbent assay.

RESULTS

The inhibition of cannabinoid receptor 1 (CB1) by the peripheral injection of an inverse agonist, namely rimonabant, decreases food intake and increases the gastric secretion and circulating levels of Nucb2/nesfatin-1. In addition, rimonabant treatment activates mTOR pathway in the stomach as showed by the increase in pmTOR/mTOR expression in gastric tissue obtained from rimonabant treated animals. These effects were confirmed by the use of a CB1 antagonist, AM281. When the intracellular pathway mTOR/S6k was inactivated by chronic treatment with rapamycin, rimonabant treatment was no longer able to stimulate the gastric secretion of Nucb2/nesfatin-1.

CONCLUSION

The peripheral cannabinoid system regulates food intake through a mechanism that implies gastric production and release of Nucb2/Nesfatin-1, which is mediated by the mTOR/S6k pathway.

Keywords: NUCB2/nesfatin-1, Stomach, Food intake, Cannabinoid receptor 1, mTOR

Core tip: The peripheral pharmacological blockade of the cannabinoid receptor 1 (CB1) induces a decrease in food intake in rats by stimulating the gastric secretion, and consequently the circulating levels, of the anorexigenic peptide Nucb2/nesfatin-1. The present data show that gastric CB1 receptors modulate Nucb2/Nesfatin-1 production in the stomach at the intracellular level, which is mediated by the mTOR pathway.