운동과 식이섭취에 의한 에너지 대사의 해석: 흰색지방을 갈색지방화 시키는 Irisin과 BAIBA를 중심으로

국문 초록 (Abstract)

인체내 에너지소모는 활동량에 의존하는 것으로 초점을 두고 있으나, 총 에너지 소모량은 활동량뿐만이 아닌 식사에 의해서도 함께 조절될 가능성이 있다. 총 에너지 소모는 식사와 운동에 있어 전체 에너지 밸런스에 의해 조절될 것이다. 본 연구에서는 최근 새롭게 발견된 백색지방을 갈색지방化 시키는 Irisin과 BAIBA가 전체 에너지소모에 있어 밸런스를 조절하는 기능을 가지고 있을 것이라 추측한다.

다국어 초록 (Multilingual Abstract)

Exercise provides clear beneficial effects for the prevention of numerous diseases. However, many of the molecular events responsible for the curative and protective role of exercise remain elusive. The recent discovery of FNDC5/irisin protein that is liberated by muscle tissue in response to exercise might be an important finding with regard to this unsolved mechanism. The most striking aspect of this myokine is its alleged capacity to drive brown-fat development of white fat and thermogenesis. However, the nature and secretion form of this new protein is controversial. The present study reveals that rat skeletal muscle secretes a 25 kDa form of FNDC5, while the 12 kDa/irisin theoretical peptide was not detected. More importantly, this study is the first to reveal that white adipose tissue (WAT) also secretes FNDC5; hence, it may also behave as an adipokine. Our data using rat adipose tissue explants secretomes proves that visceral adipose tissue (VAT), and especially subcutaneous adipose tissue (SAT), express and secrete FNDC5. We also show that short-term periods of endurance exercise training induced FNDC5 secretion by SAT and VAT. Moreover, we observed that WAT significantly reduced FNDC5 secretion in fasting animals. Interestingly, WAT of obese animals over-secreted this ho