Review
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Diabetes. May 15, 2015; 6(4): 583-597
Published online May 15, 2015. doi: 10.4239/wjd.v6.i4.583
Effects of exercise on brain functions in diabetic animal models
Sun Shin Yi
Sun Shin Yi, Department of Biomedical Laboratory Science, College of Medical Sciences, Soonchunhyang University, Asan 336-745, South Korea
Author contributions: Yi SS solely contributed to this paper.
Supported by Fund of Soonchunhyang University, South Korea.
Conflict-of-interest: I certify that there is no conflict-of-interest with any other organization.
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: Sun Shin Yi, DVM, PhD, Assistant Professor, Department of Biomedical Laboratory Science, College of Medical Sciences, Soonchunhyang University, 646, Eupnae-ri, Sinchang-myeon, Asan 336-745, South Korea. admiral96@sch.ac.kr
Telephone: +82-41-5304873 Fax: +82-41-5308085
Received: October 31, 2014
Peer-review started: November 4, 2014
First decision: November 14, 2014
Revised: January 16, 2015
Accepted: February 4, 2015
Article in press: February 9, 2015
Published online: May 15, 2015
Processing time: 195 Days and 23.6 Hours
Abstract

Human life span has dramatically increased over several decades, and the quality of life has been considered to be equally important. However, diabetes mellitus (DM) characterized by problems related to insulin secretion and recognition has become a serious health problem in recent years that threatens human health by causing decline in brain functions and finally leading to neurodegenerative diseases. Exercise is recognized as an effective therapy for DM without medication administration. Exercise studies using experimental animals are a suitable option to overcome this drawback, and animal studies have improved continuously according to the needs of the experimenters. Since brain health is the most significant factor in human life, it is very important to assess brain functions according to the different exercise conditions using experimental animal models. Generally, there are two types of DM; insulin-dependent type 1 DM and an insulin-independent type 2 DM (T2DM); however, the author will mostly discuss brain functions in T2DM animal models in this review. Additionally, many physiopathologic alterations are caused in the brain by DM such as increased adiposity, inflammation, hormonal dysregulation, uncontrolled hyperphagia, insulin and leptin resistance, and dysregulation of neurotransmitters and declined neurogenesis in the hippocampus and we describe how exercise corrects these alterations in animal models. The results of changes in the brain environment differ according to voluntary, involuntary running exercises and resistance exercise, and gender in the animal studies. These factors have been mentioned in this review, and this review will be a good reference for studying how exercise can be used with therapy for treating DM.

Keywords: Diabetes mellitus; Involuntary and voluntary exercise; Resistance exercise; Brain function; Animal models

Core tip: Brain is a highly sensitive and vulnerable tissue easily influenced by diabetes mellitus (DM). Physical exercise has been known to be one of the best non-pharmacologic ways to prevent and treat DM. Animal exercise experiments are very useful for research on DM because experiments cannot be performed in humans. Exercise has various benefits that help to improve brain function by reducing chronic inflammatory responses, accumulation of adipose tissue, appetite, insulin resistance, and dysfunction of the negative feedback mechanism. In this review, the author reports a battery of animal models of exercise, and presents the beneficial effects of exercise on the brain.