Ultrastructural features of skeletal muscle in adultudand aging Ts65Dn mice, a murine model of Downudsyndrome

摘要

Patients with Down syndrome (DS) suffer from muscle hypotonia and an altered motor coordination whose basic mechanisms are still largely unknown.udInterestingly, they show muscle weakness like healthy aged subjects, suggesting possible similarity with sarcopenia: to test this hypothesis, the Ts65Dn mouse, a suitable animal model of DS, was employed.udThe fine structure of skeletal fibres of the quadriceps femoris muscle was analysed in adult (12 months) and aging (19 months) animals and their age-matched euploid controls by combining morphometry and immunocytochemistry at transmissionudelectron microscopy. Results demonstrated structural alterations of mitochondria and myonuclei reminiscent of those observed in age-related sarcopenia, supporting the hypothesis that trisomy leads to an early aging of skeletal muscle consistent with the multi-systemic premature aging typical of DS