지방 침착률이 높은 식용소에서 나타난 골격근의 디스트로핀 소실

Abstract

This study investigated the muscular dystrophin levels in freely moving Australian cattle mainly fed grass, freely moving Korean cattle fed mainly a grain diet, and Korean cattle fed a grain diet but housed in a relatively limited space of a cow house. The total skeletal muscle specimens of 244 cattle were collected and immediately fixed in 10% neutral formalin. The same area was biopsied from the cattle in both countries. The findings showed that fatty infiltration is highly correlated with membrane- associated protein degradation in skeletal muscle, and that among several membrane-associated proteins, dystrophin showed the most significant reduction in expression in the cattle with fatty infiltration. Similarly, CD36 was more highly expressed in the cattle with fatty infiltration of skeletal muscle. Various breeding factors, such as oxidative stress; the presence of oxidized lipids in the diet; and environmental factors such as exercise, temperature and amount of time spent, may have critical effects on the degradation of normal cytoskeleton proteins, which are required for maintaining normal skeletal muscle architecture. Among the sarcolemma membrane-associated proteins, dystrophin is the most sensitive membrane protein that is involved muscular dystrophy and muscular degeneration. Thus, the present findings may be useful for studies on muscular dystrophy in humans or the pathogenesis of muscular diseases in animal models.