Morphological and biochemical assessment of apoptosis in different skeletal muscles of bulls during conditioning

Abstract

Apoptosis is a form of cell death that involves the changes of mitochondrial function and the regulated activation of caspase cascades, which selectively cleave cytoskeleton proteins and catalyze the changes of cell organelles and morphological structure. The changes of mitochondrial function, cell morphological structure, and degradation of cytoskeleton are considered to be responsible for the development of meat qualities. The LM, semitendinosus, and psoas minor (PM) muscles of 5 crossbred bulls were used to observe the morphologic and quantitative changes of apoptosis, as well as the change of caspase-3 activity during 7 d storage. Transmission electron microscopy shows that the typical features of apoptosis appeared in muscles between d 1 and 4. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) positive nuclei were detected at d 4 and increased subsequently. The count of TUNEL-positive nuclei was different in 3 muscles at d 7 (P < 0.001). There was a significant increase in caspase-3 activities at 4 h postmortem relative to the activities at the first 30 min in 3 muscles (P = 0.0147 in LM; P = 0.0058 in PM; P = 0.0306 in semitendinosus), and the apexes had 2.9 to 6.5 times more activities than activities at the first 30 min postmortem. Apoptosis did exist in 3 types of muscles during the conditioning period. Apoptosis and caspase cascades system could be associated with the postmortem development of meat quality in skeletal muscles of bulls.

The effect of calcium chloride injection on shear force and caspase activities in bovine longissimus muscles during postmortem conditioning

“…The caspase system has been shown to be involved in postmortem proteolysis and meat tenderization (HerreraMendez et al, 2006;Cao et al, 2010). However, the effect of added calcium chloride on caspase activities in muscle during postmortem conditioning needs further research.…”

Activation of caspase-9 and its influencing factors in beef during conditioning

“…Kemp et al (2006b) detected caspase-3 (20 kDa) and caspase-8 (18 kDa) active fragments in the porcine muscles. Our previously published results indicated that there was a significant increase in caspase-3 activities and that apoptosis did exist in the bovine skeletal muscles during conditioning (Cao et al, 2010 and2013). Recently, in vitro proteolytic and chemical promoters treating experiments have shown that caspases were involved in postmortem proteolysis (Chen et al, 2011;.…”

“…Animals were humanely handled as described previously (Cao et al, 2010). Five crossbred bulls (Simmental × local Chinese yellow cattle in the Anhwei province) with ages from 22 to 24 months (body weight 443 ± 48 kg) were slaughtered in a local abattoir.…”

Effects of cell death-inducing DFF45-like effector B on meat quality traits in Berkshire pigs

“…Moreover, sHSPs are chaperones that maintain cellular homeostasis and ultimately affect meat quality (Lomiwes et al, 2014). Therefore, a study has suggested that apoptosis and caspase activities can affect post-mortem meat quality (Cao et al, 2010). Apoptosis often occurs under specialized cellular conditions, such as cleavage of cytoskeletal proteins and cellular components, shrinkage of muscle cells, and loss of membrane asymmetry, which can lead to changes in meat quality (Sierra and Oliván, 2013).…”

“…In addition, some studies suggest that apoptosis during post-mortem conditioning is associated with meat quality (Cao et al, 2010). Small heat shock proteins (sHSPs) are well known anti-apoptotic molecules that regulate meat quality (Ouali et al, 2006).…”