Effects of intermittent ladder-climbing exercise training on mitochondrial biogenesis and endoplasmic reticulum stress of the cardiac muscle in obese middle-aged rats.
10.4196/kjpp.2017.21.6.633
- Author:
Kijin KIM
1
;
Nayoung AHN
;
Suryun JUNG
;
Solee PARK
Author Information
1. Department of Physical Education, College of Physical Education, Keimyung University, Daegu 42601, Korea. kjk744@kmu.ac.kr
- Publication Type:Original Article
- Keywords:
Aging;
Cardiac muscle;
ER stress;
High-fat diet-induced obesity;
Ladder climbing exercise;
Mitochondrial biogenesis
- MeSH:
Aging;
Animals;
Body Weight;
Diet;
Diet, High-Fat;
Endoplasmic Reticulum Stress*;
Endoplasmic Reticulum*;
Energy Intake;
Humans;
Intra-Abdominal Fat;
Male;
Myocardium*;
Obesity;
Organelle Biogenesis*;
Rats*;
Rats, Sprague-Dawley
- From:The Korean Journal of Physiology and Pharmacology
2017;21(6):633-641
- CountryRepublic of Korea
- Language:English
-
Abstract:
The aim of this study is to investigate the effects of intermittent ladder-climbing exercise training on mitochondrial biogenesis and ER stress of the cardiac muscle in high fat diet-induced obese middle-aged rats. We induced obesity over 6 weeks of period in 40 male Sprague-Dawley rats around 50 weeks old, and were randomly divided into four experimental groups: chow, HFD, exercise+HFD, and exercise+chow. The exercising groups underwent high-intensity intermittent training using a ladder-climbing and weight exercise 3 days/week for a total of 8 weeks. High-fat diet and concurrent exercise resulted in no significant reduction in body weight but caused a significant reduction in visceral fat weight (p<0.05). Expression of PPARδ increased in the exercise groups and was significantly increased in the high-fat diet+exercise group (p<0.05). Among the ER stress-related proteins, the expression levels of p-PERK and CHOP, related to cardiac muscle damage, were significantly higher in the cardiac muscle of the high-fat diet group (p<0.05), and were significantly reduced by intermittent ladder-climbing exercise training (p<0.05). Specifically, this reduction was greater when the rats underwent exercise after switching back to the chow diet with a reduced caloric intake. Collectively, these results suggest that the combination of intermittent ladder-climbing exercise training and a reduced caloric intake can decrease the levels of ER stress-related proteins that contribute to cardiac muscle damage in obesity and aging. However, additional validation is required to understand the effects of these changes on mitochondrial biogenesis during exercise.
