Wang H, Esemu-Ezewu P, Pan J, Ivanovska J, Gauda EB, Belik J. Adiponectin and the regulation of gastric content volume in the newborn rat. World J Gastroenterol 2021; 27(33): 5566-5574 [PMID: 34588752 DOI: 10.3748/wjg.v27.i33.5566]
Corresponding Author of This Article
Jaques Belik, FRCP (C), MD, Professor, Department of Paediatrics and Physiology, The Hospital for Sick Children, 555 University Ave, Toronto M5G 1X8, Ontario, Canada. jaques.belik@sickkids.ca
Research Domain of This Article
Gastroenterology & Hepatology
Article-Type of This Article
Basic Study
Open-Access Policy of This Article
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/
World J Gastroenterol. Sep 7, 2021; 27(33): 5566-5574 Published online Sep 7, 2021. doi: 10.3748/wjg.v27.i33.5566
Adiponectin and the regulation of gastric content volume in the newborn rat
Huanhuan Wang, Paul Esemu-Ezewu, Jingyi Pan, Julijana Ivanovska, Estelle B Gauda, Jaques Belik
Huanhuan Wang, Paul Esemu-Ezewu, Jingyi Pan, Julijana Ivanovska, Estelle B Gauda, Department of Paediatrics, The Hospital for Sick Children, Toronto M5G 1X8, Ontario, Canada
Jaques Belik, Department of Paediatrics and Physiology, The Hospital for Sick Children, Toronto M5G 1X8, Ontario, Canada
Author contributions: Wang H, Esemu-Ezewu P, Pan J and Ivanovska J performed the experiments, acquired and analyzed the data and contributed to drafting the manuscript; Gauda EB and Belik J designed, coordinated the study and finalized the manuscript.
Supported byCanadian Institutes of Health Research, No. CIA310955.
Institutional animal care and use committee statement: All procedures were conducted in accordance with the Canadian Animals for Research Act and Canadian Council on Animal Care regulations, and the Hospital for Sick Children Research Institute Animal Care Committee approved the study, No. 1000046424.
Conflict-of-interest statement: The authors have no conflict of interest to declare.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at jaques.belik@sickkids.ca.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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/
Corresponding author: Jaques Belik, FRCP (C), MD, Professor, Department of Paediatrics and Physiology, The Hospital for Sick Children, 555 University Ave, Toronto M5G 1X8, Ontario, Canada. jaques.belik@sickkids.ca
Received: March 9, 2021 Peer-review started: March 9, 2021 First decision: May 1, 2021 Revised: May 12, 2021 Accepted: August 12, 2021 Article in press: August 12, 2021 Published online: September 7, 2021 Processing time: 178 Days and 10.8 Hours
Abstract
BACKGROUND
Oral intake is dependent on the gastric ability to accommodate the food bolus. Comparatively, neonates have a smaller gastric capacity than adults and this may limit the volume of their milk intake. Yet, we previously reported that the newborn rat gastric milk volume is greatest after birth and, when normalized to body weight, decreases with postnatal age. Such age-dependent changes are not the result of intake differences, but greater gastric accommodation and reduced emptying rate.
AIM
Hypothesizing that breastmilk-derived adiponectin is the factor regulating gastric accommodation in neonates, we comparatively evaluated its effects on the rat fundic muscle tone at different postnatal ages.
METHODS
In freshly dispersed smooth muscle cells (SMC), we measured the adiponectin effect on the carbachol-induced length changes.
RESULTS
Adiponectin significantly reduced the carbachol-stimulated SMC shortening independently of age. In the presence of the inhibitor iberiotoxin, the adiponectin effect on SMC shortening was suppressed, suggesting that it is mediated via large-conductance Ca2+ sensitive K+ channel activation. Lastly, we comparatively measured the newborn rat gastric milk curd adiponectin content in one- and two-week-old rats and found a 50% lower value in the latter.
CONCLUSION
Adiponectin, a major component of breastmilk, downregulates fundic smooth muscle contraction potential, thus facilitating gastric volume accommodation. This rodent’s adaptive response maximizes breastmilk intake volume after birth.
Core Tip: Gastric accommodation regulates the stomach content volume. Lactating rats continuously breastfeed to keep a full gastric milk volume and their gastric emptying time is directly related to the gastric content volume. Little is known about the gastric fundic accommodation regulatory factors early in life. In this study, breastmilk-derived adiponectin is shown to promote gastric fundic relaxation, thus playing an important regulatory role during the lactating period.
