초록

이 연구는 고지방식이 유발 비만 쥐의 8주간 규칙적인 트레드밀 운동이 인슐린 신호 전달 경로인 IRS-1/PI3K/Akt 단백질 수준과 mTOR 경로인 mTOR/mTORC1/S6K1의 변화를 살펴보기 위하여 실시하였다. 실험동물은 4주령 sprague-dawley rat 수컷 24마리를 1주간의 적응기간을 둔 뒤, 15주간 고지방식이로 비만을 유도하였다. 실험 동물은 고지방식이군(OD, n=8), 고지방식이 훈련군(ODT, n=8), 정상식이군(ND, n=8)으로 분류하였다. 트레드밀 운동은 1~4주는 주 5회 40분간 실시하였으며, 5~8주는 주5회 60분간 실시하였다. 그 결과 IRS-1과 PI3K는 OD군이 ND와 ODT군에 비해 유의하게 낮게 나타났다(p＜0.05). 그리고 mTOR와 S6K1은 OD군이 ND와 ODT군에 비해 유의한 차이가 나타났다(p＜0.05). 따라서 고지방식이 비만 유발 쥐의 8주간 규칙적인 트레드밀 운동은 골격근의 인슐린 신호 경로인 IRS-1과 PI3K 단백질 수준 향상에 긍정적 영향을 주며, 또한 mTOR 경로에서 S6K1을 개선시키는 것으로 나타나, 인슐린 신호경로와 S6K1의 변화를 통해 인슐린 민감성의 향상을 가져온 것으로 사료된다.

키워드

주요어: 고지방 식이 유도 비만쥐, 인슐린 신호 경로, mTOR pathway, mTORC1, S6K1

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