Dupont-Versteegden Esther E
Department of Geriatrics, Institute on Aging, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR 72205, USA.
Exp Gerontol. 2005 Jun;40(6):473-81. doi: 10.1016/j.exger.2005.04.003.
The loss of muscle mass with aging, or sarcopenia, is an important contributor to the functional decline and loss of independence observed with aging. Little is known about the role of apoptosis in sarcopenia. Studies in adult animals have shown that apoptosis is involved in the loss of muscle nuclei during acute disuse atrophy, and caspase-3 dependent pathways play an important role in this process. Elevated apoptosis has also been observed in muscles of aged animals, but this does not depend upon caspase-3 pathways to the same extent as disuse atrophy. Moreover, disuse atrophy induced in aged animals is associated with a higher amount of apoptosis than in young and intracellular mechanisms are different from those in young, depending more on caspase-independent pathways. The functional relevance of the increase in apoptosis with respect to the loss of muscle fibers and muscle cross-sectional area with aging remains to be determined and interventions to decrease apoptosis in muscle need to be evaluated.
随着年龄增长出现的肌肉质量流失，即肌肉减少症，是导致衰老过程中功能衰退和失去独立生活能力的一个重要因素。关于细胞凋亡在肌肉减少症中的作用，人们了解甚少。对成年动物的研究表明，细胞凋亡参与了急性废用性萎缩期间肌核的丢失，且半胱天冬酶-3依赖性途径在此过程中起重要作用。在老年动物的肌肉中也观察到细胞凋亡增加，但这与废用性萎缩在同等程度上并不依赖半胱天冬酶-3途径。此外，与年轻动物相比，老年动物诱导的废用性萎缩与更高程度的细胞凋亡相关，且细胞内机制也有所不同，更多地依赖非半胱天冬酶依赖性途径。细胞凋亡增加与衰老过程中肌肉纤维和肌肉横截面积丢失之间的功能相关性仍有待确定，且需要评估减少肌肉细胞凋亡的干预措施。
