Age related skeletal muscle atrophy and upregulation of autophagy in dogs

Age-Related Changes in Skeletal Muscle of Cattle

“…41,43 In brief, the cryosections where incubated with primary antibodies (diluted in phosphate-buffered saline) overnight at 4 C. After 2 washes 15 We used specific controls for each immunohistochemistry assay as follows: for antibodies directed against lymphocytes and plasma cell antigens, we used sections from bovine lymph nodes belonging to the archive of Veterinary Medicine Department of University of Naples Federico II. Blood vessel endothelial cells within sections were used as internal control for MHC I expression.…”

“…16,38 The word ''sarcopenia'' was used for the first time in 1989 by Irwin Rosenberg to state the age-related decrease of muscle mass. 12,43,44,45 At present, sarcopenia has been defined as the condition of muscle wasting strictly linked to aging, characterized by loss of skeletal muscle mass and function, which may affect both animals and humans, at different stages of severity 12,27,43 ; it is characterized by gradual loss of skeletal muscle mass resulting in decline of muscle function characterized by a decline in force-producing capacity and maximum velocity of shortening of muscle fibers.48 These age-related alterations in skeletal muscle are attributed to a complex of factors involving neuromuscular junction, 26 muscle structure (architecture and fiber composition), and metabolism. 43,47,49 The loss of muscle mass and strength results from the progressive atrophy and loss of single muscle fibers, 23 along with loss of both types of motor units (slow and fast).…”

“…43,47,49 The loss of muscle mass and strength results from the progressive atrophy and loss of single muscle fibers, 23 along with loss of both types of motor units (slow and fast). 36 Several studies 36,55 indicate that, in sarcopenia, type II fibers (fast-twitch) seem to be more likely to undergo atrophy than type I fibres.…”

“…3 Sarcopenia has been described in several animal species, from nematodes, flies, rodents, domestic and wild animals, and nonhuman primates to humans. 6,32,39,43,45,52 No information is available about sarcopenia in farm animals because of their short period of lifespan. Some exceptions are presented, such as Podolica breed, which is a dual-purpose bovine breed very common in the south of Italy that it is usually raised free outdoors in the mountains with a lifespan of about 15 years.…”

Neuromuscular junction degeneration in muscle wasting

“…This further supported a major role of autophagy for neuromuscular junction homeostasis. Accordingly, autophagy was found to be dysregulated in skeletal muscle of aging dogs [12] and humans [11]. It has been determined that caloric restriction and physical exercise are beneficial for rescuing neuromuscular junction fragmentation [2,13,8] and innervation status [2,14], and at the same time reduce impairment of autophagy [11] as well as sarcopenia onset or progression [15–18].…”