Postmortem mitochondria function in longissimus lumborum of Angus and Brahman steers.
Meat Sci
; 215: 109538, 2024 Sep.
Article
em En
| MEDLINE
| ID: mdl-38772311
ABSTRACT
Mitochondria function and integrity may impact postmortem metabolism and meat quality development. Adaptations in heat tolerant Brahman may persist to limit cellular stress postmortem. Our objective was to evaluate glycolysis, pH decline, and mitochondria function in longissimus lumborum (LL) from Angus and Brahman steers (N = 28) early postmortem (1 to 6 h) and after rigor (24 h). We evaluated metabolites of anaerobic glycolysis, ATP, pH, and temperature, and determined mitochondria oxygen consumption rate (OCR) in permeabilized fibers. The main effects of breed (b) and time (t) and the interaction were tested. Brahman LL contained greater ATP during the first 6 h postmortem; Brahman also tended to exhibit a slower pH decline (b × t, P = 0.07) and more rapid temperature decline (b × t, P < 0.001), but metabolites of anaerobic glycolysis were not different. Mitochondria in Brahman and Angus LL were well-coupled and respired at 1 h postmortem. However, outer membrane integrity became increasingly compromised postmortem (t, P < 0.001). Brahman tended to exhibit greater electron transport system capacity (b, P < 0.1) and had greater capacity for oxidative phosphorylation (complex I and II substrates) at 6 h compared with Angus (P < 0.001). In totality, greater ATP, slower pH decline, and enhanced mitochondria capacity indicate that Brahman possess mitochondrial properties or cellular adaptations that help protect the cell during energy stress postmortem. Slower pH and more rapid temperature decline in LL from Brahman may also help preserve mitochondria function postmortem.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fosforilação Oxidativa
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Mudanças Depois da Morte
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Trifosfato de Adenosina
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Músculo Esquelético
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Carne Vermelha
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Glicólise
Limite:
Animals
Idioma:
En
Revista:
Meat Sci
/
Meat sci
/
Meat science
Assunto da revista:
CIENCIAS DA NUTRICAO
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Estados Unidos