Age-dependent imbalance of the antioxidative system in human satellite cells
Age-dependent imbalance of the antioxidative system in human satellite cells
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DOI：
10.1016/j.exger.2004.11.006
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发表时间：
2005-03-01
影响因子：
3.9
通讯作者：
Fanò, G
中科院分区：
文献类型：
--
作者：
Fulle, S;Di Donna, S;Fanò, G
人类骨骼肌的成熟肌纤维被一种被称为卫星细胞的成体干细胞所包围，这种干细胞位于肌膜外但在基板内。这些细胞保持静止，直到外界刺激触发它们重新进入细胞周期。在人类中，衰老的特征是肌肉质量和力量的进行性丧失(石棺减少)，与功能能力下降有关。肌肉机能下降的可能原因之一是骨骼肌的抗氧化能力下降，导致对细胞生命至关重要的活性氧物种(ROS)的异常积累。本研究表明：(I)老年人来源的卫星细胞的过氧化氢酶和谷胱甘肽转移酶的抗氧化活性与年轻人分离的细胞相比显著降低；(Ii)两个年龄组的细胞膜流动性有很大差异；(Iii)卫星细胞的基础[Ca~(2+)](I)水平随年龄的增加而显著升高。鉴于所获得的数据，我们假设骨骼肌老化过程中发生的破坏稳定的氧化损伤也会影响静止的卫星细胞，这些细胞的生命与成年纤维密切解剖和功能接触。这种状态源于抗氧化能力的下降，并可能对老化的卫星细胞修复肌肉的能力产生负面影响。(C)2004 Elsevier Inc.保留所有权利。
The mature myofibres of human skeletal muscle are surrounded by a type of adult stem cell, known as the satellite cell, which lies outside the sarcolemma but within the basal lamina. These cells remain quiescent until external stimuli trigger their re-entry into the cell cycle. In humans, ageing is characterised by a progressive loss of muscle mass and strength (sarcopenia) associated with a decline in functional ability. One of the possible causes of this decline in muscle performance is a decrease in the antioxidative capacity of skeletal muscle, resulting in an abnormal accumulation of the reactive oxygen species (ROS) critical for cell life. The present study shows that: (i) the antioxidant activity of Catalase and Gluthatione transferase in satellite cells derived from the elderly is drastically reduced compared to that in cells isolated from young individuals; (ii) cell membrane fluidity is considerably different between the two age groups; and (iii) basal [Ca2+](i) levels in satellite cells increase significantly in an age-dependent manner. In view of the data obtained, we hypothesise that the destabilising oxidative damage that occurs during ageing in skeletal muscle also affects quiescent satellite cells, which spend their life in close anatomic and functional contact with adult fibres. This status is derived from a decrease in the antioxidative capacity, and may negatively affect the ageing satellite cells ability to repair muscle. (c) 2004 Elsevier Inc. All rights reserved.