Dystrophin Cleavage and Sarcolemma Detachment are Early Post Mortem Changes on Bass (Dicentrarchus labrax) White Muscle

Abstract

Using specific dystrophin antibodies directed against a conserved C-terminal sequence, we demonstrated that dystrophin of fish white muscle was quickly degraded by 50% within 24h and by 100% within 2 days, in parallel with titin cleavage and alpha-actinin release from Z-disks. These changes were accompanied by sarcolemma detachment from the myofibers in costameres (the structures containing dystrophin) and Zdisks weakening. For muscle stored during 2 to 6 mo before thawing, total dystrophin disappearance was observed at 4ЊC in Ͻ8h. Dystrophin may serve as a marker for stored fish to evaluate post mortem changes or detect a thawing-freezing process.

Breakdown of intramuscular connective tissue in cod (Gadus morhua L.) and spotted wolffish (Anarhichas minor O.) related to gaping

“…Similar breakdown of the endomysial sheaths has been reported in other fish species (Ando et al, 1991(Ando et al, , 1992Taylor et al, 2002), avian (Liu, Nishimura, & Takahashi, 1994, 1995 and mammalian muscle (Hannesson et al, 2003;Taylor & Koohmaraie, 1998). Detachment of the sarcolemma was ascribed to breaks in the muscle cytoskeleton connection from the sarcomeres to the endomysium (Papa et al, 1997;Taylor & Koohmaraie, 1998;Taylor et al, 2002). Weakening of the pericellular connective tissue induced by disintegration of thin collagen fibrils in rainbow trout and sardine (Sardinops melanosticta) muscle, was ascribed to degradation of type V collagen (Sato et al, 1997;Sato, Koike, Yoshinaka, Sato, & Shimizu, 1994;Sato, Ohashi, Ohtsuki, & Kawabata, 1991).…”

Muscle tissue structural changes and texture development in sea bream, Sparus aurata L., during post-mortem storage

“…In general, myofibrils are more stable in fish than in mammals thus showing higher integrity of I-band in fish (Taylor et al, 2002(Taylor et al, , 1994Taylor & Koohmaraie, 1998). However, studies performed in teleots show intra-and interspecific differences in relation with the level of alteration (Davie & Sparksman, 1986;Ofstad et al, 1996;Papa et al, 1997). Thus, it is necessary a better understanding between the muscle disorganization and textural degradation in order to control the quality of the end product in the markets.…”

Stress relaxation behaviour and structural changes of muscle tissues from Gilthead Sea Bream (Sparus aurata L.) following high pressure treatment

“…Except for a slight alteration of few bands, mostly in the 100 kDa and 80 kDa area, there were no substantial differences in intensity of protein bands as a consequence of treatments and of storage. In general, the major documented changes during post-mortem storage are weakening of the Z-line, degradation of titin, nebulin, dystrophin, desmin, as well as release of a-actinin from the Z-line, and breakdown of collagen junctions between myotomes (Papa et al, 1997;Delbarre-Ladrat et al, 2006).…”