The current study is conducted to study the adverse effect of aging on the histological architecture and immunohistochemical (IHC) cytoskeleton of rabbit's skeletal muscle fibers and the preventive role of vitamin E on elderly animals. Twenty-one male New Zeland rabbits were divided into three groups. Group I: represented the adult rabbits (6 months of age, weighing 4 ± 0.5 kg), group II included aged rabbits (24-months of age, weighing 7.5 ± 0.5 kg), and group III consisted of aged animals given a daily therapeutic dose of vitamin E orally at 14 mg/kg b.w /day for 60 days. The histological structure of skeletal muscles of aged rabbits revealed variety of changes in the form of disorganization of muscle fibers with loss of transverse striations, sarcoplasmic degeneration, infiltration of inflammatory cells, congestion and dilation of blood vessels and pyknotic nuclei. IHC study revealed an increase in the intensity of both desmin and vimentin filaments immunoreactivity in skeletal muscle fibers of aged animals with irregular distribution of desmin immunostain within the aged myocytes. Vitamin E supplementation to senescent animals showed a remarkable effectiveness in restoring the normal histological structure of skeletal muscles as well as the cytoskeletal proteins structure of either desmin or vimentin and became more or less similar to the adult ones. Therefore, the present work recommends using vitamin E to delay or relieve the changes in skeletal muscles that accompany aging.
Key words: Skeletal muscles, Aging, Vitamin E, Histology, Immunohistochemistry, Intermediate Filaments, Desmin, Vimentin, Rabbit.