단기간 트레드밀 운동을 통한 in vivo 미토파지 실험모델 검증 = Validation of an in vivo Mitophagy Experimental Model through Short-Term Treadmill Exercise

국문 초록 (Abstract)

미토콘드리아는 에너지공급 및 다양한 신호전달을 통해 세포의 항상성에 관여한다. 미토콘드리아의 손상은 만성질환과 밀접하게 관련되어 있으며, 질병 치료 및 예방목적으로 활발하게 연구되고 있다. 미토파지(mitophagy)는 손상된 미토콘드리아를 선택적으로 제거하여 세포기능의 유지 및 개선에 중요한 역할을 담당하는 세포 작용이다. 규칙적인 운동은 손상된 미토콘드리아를 제거하여 미토콘드리아 질적 조절을 통해 생리적 대사 및 기능을 제어하는 것으로 알려져 있다. 지금까지 미토파지 평가에 대한 연구방법은 많이 발전되어 왔지만, 미토파지 관련 현상의 in vivo 검증은 부족하다. 따라서 본 연구는 1주간의 마우스 트레드밀 운동이 골격근의 선택적 미토콘드리아 제거 신호에 미치는 영향을 mt-Kiema 마우스를 통해 분석하였다. 그 결과, 운동(EX)군이 대조(CON)군에 비해 더 높은 미토파지(red 형광) 수준을 나타냈으며, 이는 미토파지-관련 단백질 발현 결과와 유사성을 보였다. 본 연구는 in vivo 미토파지 평가 모델을 통해 미토콘드리아 질적조절에 대한 운동중재 효과를 보다 정확하게 검증할 수 있는 방법으로, 향후 본 연구모델의 활용가치가 높을 것으로 사료된다.

다국어 초록 (Multilingual Abstract)

Mitochondria are intracellular organelles, involve in regulating cellular homeostasis through various signaling pathways. Damaged mitochondria are closely related to chronic diseases, and have been actively studied for the patho-physiologic conditions. Mitophagy is a cellular mechanism of action that plays an important role in maintaining and improving cellular functions by selectively removing damaged mitochondria and exercise regimen is known to regulate mitochondrial quality control including the process of mitophagy. In this study, the effect of treadmill exercise for 1 week on the in vivo mitophagy of skeletal muscle was analyzed using mt-keima transgenic mice. As a result, the higher red fluorescence (pH 4.0; excitation: 561nm, emission range: 570-695nm) ratio was observed on confocal microscopy in the exercise (EX) group vs. the control (CON) group. These results were also consistent with the data that observed protein levels which are known to be induced during mitophagy. Therefore, the effect of exercise intervention on mitochondrial quality control can be more accurately verified through validation using the in vivo mitophagy evaluation model, mt-Kiema mice.

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