TY - JOUR
T1 - Loss of dystrophin and some dystrophin-associated proteins with concomitant signs of apoptosis in rat leg muscle overworked in extension
AU - Biral, Donatella
AU - Jakubiec-Puka, A.
AU - Ciechomska, Iwona
AU - Sandri, Marco
AU - Rossini, Katia
AU - Carraro, Ugo
AU - Betto, Romeo
PY - 2000
Y1 - 2000
N2 - This study investigated the basis for the high severity of damage to skeletal muscle due to eccentric exercise, i.e., to muscles generating force while lengthened. Fast and slow rat leg muscles maintained in an extended position were examined after 2-24 h of continuous stimulation. The treatment caused the injury to some regions of both muscles. Within the better preserved parts of the muscles, i.e., those without signs of necrotic processes, dystrophin, spectrin, and some of the dystrophin-associated proteins (β-dystroglycan, α-sarcoglycan, and γ-sarcoglycan) disappeared from sarcolemma of many fibers. The reduction or loss of dystrophin from the sarcolemma was more evident than that of other proteins examined, with sarcoglycans apparently being the most preserved. Several muscle fibers devoid of dystrophin contained apoptotic nuclei. Simultaneously, Bax, Bcl-2 and caspase-3 proteins appeared in many fibers. Our results indicate that a normal muscle overworking in an extended position undergoes the loss of several membrane skeletal proteins because of the excessive stress to the membrane cyto-skeleton, which can lead to fiber death by either apoptosis or necrosis. This experimental model may represent a good model for mimicking the pathogenetic events in several muscular dystrophies.
AB - This study investigated the basis for the high severity of damage to skeletal muscle due to eccentric exercise, i.e., to muscles generating force while lengthened. Fast and slow rat leg muscles maintained in an extended position were examined after 2-24 h of continuous stimulation. The treatment caused the injury to some regions of both muscles. Within the better preserved parts of the muscles, i.e., those without signs of necrotic processes, dystrophin, spectrin, and some of the dystrophin-associated proteins (β-dystroglycan, α-sarcoglycan, and γ-sarcoglycan) disappeared from sarcolemma of many fibers. The reduction or loss of dystrophin from the sarcolemma was more evident than that of other proteins examined, with sarcoglycans apparently being the most preserved. Several muscle fibers devoid of dystrophin contained apoptotic nuclei. Simultaneously, Bax, Bcl-2 and caspase-3 proteins appeared in many fibers. Our results indicate that a normal muscle overworking in an extended position undergoes the loss of several membrane skeletal proteins because of the excessive stress to the membrane cyto-skeleton, which can lead to fiber death by either apoptosis or necrosis. This experimental model may represent a good model for mimicking the pathogenetic events in several muscular dystrophies.
KW - Apoptosis
KW - Dystrophin
KW - Dystrophin-associated proteins
KW - Eccentric exercise
KW - Skeletal muscle
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U2 - 10.1007/s004010000231
DO - 10.1007/s004010000231
M3 - Article
C2 - 11078213
AN - SCOPUS:0033774696
VL - 100
SP - 618
EP - 626
JO - Acta Neuropathologica
JF - Acta Neuropathologica
SN - 0001-6322
IS - 6
ER -