TY - JOUR
T1 - Cellular aging of skeletal muscle
T2 - telomeric and free radical evidence that physical inactivity is responsible and not age.
AU - Venturelli, Massimo
AU - Morgan, Garrett R.
AU - Donato, Anthony J.
AU - Reese, Van
AU - Bottura, Renato
AU - Tarperi, Cantor
AU - Milanese, Chiara
AU - Schena, Federico
AU - Reggiani, Carlo
AU - Naro, Fabio
AU - Cawthon, Richard M.
AU - Richardson, Russell S.
PY - 2014
Y1 - 2014
N2 - Telomeres play an essential role in maintaining chromosomal integrity in the face of physiological stressors. Although the age-related shortening of TL (telomere length) in highly proliferative tissue is predominantly due to the replication process, the mechanism for telomere shortening in skeletal muscle, which is minimally proliferative, is unclear. By studying TL in both the upper and lower limbs of the young, old-mobile and old-immobile subjects and by virtue of the bipedal nature of human locomotion, which declines with age, it may be possible to elucidate the mechanism(s) responsible for cellular aging of skeletal muscle. With this approach, we revealed that TL (~15 kb) in arm skeletal muscle is unaffected by age. In contrast TL fell progressively in the legs across the young (~15 kb), the old mobile (~13 kb) and old immobile (~11 kb) subjects. Interestingly, there was a reciprocal increase in leg muscle free radicals across these groups that was correlated with TL (r=0.7), with no such relationship in the arm (r=0.09). Our results document that chronological age does not affect the cellular aging of skeletal muscle, but reveals that physical inactivity, probably mediated by free radicals, has a profound effect upon this process.
AB - Telomeres play an essential role in maintaining chromosomal integrity in the face of physiological stressors. Although the age-related shortening of TL (telomere length) in highly proliferative tissue is predominantly due to the replication process, the mechanism for telomere shortening in skeletal muscle, which is minimally proliferative, is unclear. By studying TL in both the upper and lower limbs of the young, old-mobile and old-immobile subjects and by virtue of the bipedal nature of human locomotion, which declines with age, it may be possible to elucidate the mechanism(s) responsible for cellular aging of skeletal muscle. With this approach, we revealed that TL (~15 kb) in arm skeletal muscle is unaffected by age. In contrast TL fell progressively in the legs across the young (~15 kb), the old mobile (~13 kb) and old immobile (~11 kb) subjects. Interestingly, there was a reciprocal increase in leg muscle free radicals across these groups that was correlated with TL (r=0.7), with no such relationship in the arm (r=0.09). Our results document that chronological age does not affect the cellular aging of skeletal muscle, but reveals that physical inactivity, probably mediated by free radicals, has a profound effect upon this process.
UR - http://www.scopus.com/inward/record.url?scp=84905100661&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84905100661&partnerID=8YFLogxK
U2 - 10.1042/CS20140051
DO - 10.1042/CS20140051
M3 - Article
C2 - 24708050
AN - SCOPUS:84905100661
VL - 127
SP - 415
EP - 421
JO - Clinical Science
JF - Clinical Science
SN - 0143-5221
IS - 6
ER -