title: The effect of exercise on expression of myokine and angiogenesis mRNA in skeletal muscle of high fat diet induced obese rat.
abstract: OBJECTIVE
  The purpose of this study was to investigate the effect of regular treadmill exercise on the mRNA expressions of myokines and angiogenesis factors in the skeletal muscle of obese rats.
  
  
  METHODS
  Thirty two male Sprague-Dawley rats (4weeks old) were divided into the CO (control) and HF (high fat diet) groups. Obesity was induced in the HF group by consumption of 45% high-fat diet for 15 weeks. These groups were further subdivided into training groups (COT and HFT); the training groups conducted moderate intensity treadmill training for 8 weeks. Soleus muscles were excised and analyzed by real-time quantitative PCR.
  
  
  RESULTS
  mRNA expression of myokines, such as PGC-1α, IL-6, and IL-15, in the COT and HFT groups (which conducted regular exercise), were higher as compared with the CO and HF groups (p < 0.05). Also, the levels in the HF group were significantly lower when compared with CO group (p < 0.05). Expression of angiogenesis mRNA, namely mTOR, VEGF, and FLT1, were significantly lower in the HF group, as compared to the CO group (p < 0.05). In addition, COT group had a higher expression of mTORC1, mTORC2, VEGF and FLT mRNA, than the CO group (p < 0.05); the HFT group also had higher expressions of mTOR, VEGF and FLT1 mRNA than the HF group (p < 0.05).
  
  
  CONCLUSIONS
  These results indicate that mRNA expression of myokines was increased through the activity of muscle contraction, and it also promoted the mRNA expression of angiogenesis due to activation of mTOR. Thus, we conclude that not only under normal health conditions, but in obesity and excess nutritional circumstances also, regular exercise seems to act positively on the glycemic control and insulin sensitivity through the angiogenesis signaling pathway.
authors.affiliation: Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan, Republic of Korea.
authors.forename: Ki Ok
authors.initials: KO
authors.lastname: Shin
authors.affiliation: Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan, Republic of Korea.
authors.forename: Ju Yong
authors.initials: JY
authors.lastname: Bae
authors.affiliation: Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan, Republic of Korea.
authors.forename: Jinhee
authors.initials: J
authors.lastname: Woo
authors.affiliation: Laboratory of Exercise Biochemistry, Department of Physical Education, Dong-A University, Busan, Republic of Korea.
authors.forename: Ki Soeng
authors.initials: KS
authors.lastname: Jang
authors.affiliation: Department of Physical Education, Korea Air Force Academy, Cheongju, Republic of Korea.
authors.forename: Keun Su
authors.initials: KS
authors.lastname: Kim
authors.affiliation: Department of Physical Education, Korea Air Force Academy, Cheongju, Republic of Korea.
authors.forename: Jung Sub
authors.initials: JS
authors.lastname: Park
authors.affiliation: Department of Physical Education, Korea Air Force Academy, Cheongju, Republic of Korea.
authors.forename: In Ki
authors.initials: IK
authors.lastname: Kim
authors.affiliation: Department of Physical Education, Korea Air Force Academy, Cheongju, Republic of Korea.
authors.forename: Sunghwun
authors.initials: S
authors.lastname: Kang
keywords: Regular exercise; angiogenesis; mRNA expression; myokine; obesity