Effect of treadmill exercise on ER stress and insulin resistance in the hippocampus of high-fat diet fed rats

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doi:2015.24.2.143

Exerc Sci > Volume 24(2); 2015 > Article

Exercise Science 2015;24(2): 143-151. doi: https://doi.org/10.15857/ksep.2015.24.2.143

트레드밀 운동이 고지방 식이 쥐의 해마에서의 소포체 스트레스와 인슐린 저항성에 미치는 영향

강은범

한국체육대학교

Effect of treadmill exercise on ER stress and insulin resistance in the hippocampus of high-fat diet fed rats

ABSTRACT

PURPOSE:
The purpose of this study was to investigate the impacts of 8-week treadmill exercise on glycose metabolism, insulin resistance and ER stress-related factors in hippocampal tissue with experimental animals for which obesity was induced through a 20 week high-fat diet.
METHODS:
High-fat feed was provided for 20-week-old SD rats in order to induce obesity for 20 weeks. The experimental animals were divided into a Normal Diet Control Group (ND-CON, n=6), a High-Fat Diet Control Group (HFD-CON, n=6) and a High-Fat Diet Exercise Group (HFD-EXE, n=6). The treadmill exercise was conducted, 30 minutes a day, four days a week for eight weeks. After the treadmill exercise, their weight, AUC and HOMA-IR were analyzed, and using the Western blot method, ER stress-related variables (GRP78/BiP, PERK, ATF6, IRE1α, eIF2α, XBP-1S & CHOP) were analyzed.
RESULTS:
In the HFD-CON Group, as compared to the ND-CON Group, the weight increased; blood glucose disposal capacity decreased; and HOMA-IR increased. In addition, the expression of ER stress-related variables, also, increased, so the signal transduction mechanism for cell death was activated. However, in the HFD-EXE Group that conducted treadmill exercise, as compared to the HFD-CON Group, the weight decreased; blood glucose disposal capacity improved; and HOMA-IR, also, decreased. ER stress-related variables decreased in the HFD-EXE Group as compared to the HFD-CON Group, and consequently, ER stress decreased.
CONCLUSIONS:
In conclusion, it was found that aerobic exercise like treadmill exercise would play positive roles in improving the imbalance of energy metabolism in the body induced by obesity and controlling ER stress induced from hippocampal tissue.

Key words: treadmill exercise, obesity, brain, ER stress