Endoplasmic reticulum stress improved chicken tenderness, promoted apoptosis and autophagy during postmortem ageing

In this study, endoplasmic reticulum (ER) stress inducer tunicamycin (TM) and inhibitor 4-phenylbutyric acid (4-PBA) were used to treat postmortem chicken breast muscle to investigate changes in tenderness and effects on apoptosis and autophagy during 5 days ageing. TM -induced ER stress reduced shear force, enhanced myofibril fragmentation index (MFI), disrupted myofibril structure, increased desmin degradation, and activated mu-calpain and caspase-12. In addition, TM -induced ER stress increased the expression of Bax, Bim, and cytochrome c, and decreased the expression of Bcl-xL. Furthermore, TM -induced ER stress improved the conversion of LC3I to LC3II, raised the expression of Beclin-1, and decreased the expression of p62, PI3K, and mTOR. The opposite results were observed after 4-PBA treatment. These results suggested that ER stress could improve chicken tenderness, promote apoptosis and autophagy during chicken postmortem ageing. (c) 2024 Beijing Academy of Food Sciences. Publishing services by Tsinghua University Press. This is an open access article under the CC BY -NC -ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).