Reduced water-holding capacity of beef during refrigeration is associated within creased heme oxygenase 1 expression, oxidative stress and ferroptosis.

Low molecular weight iron (LMW-Fe)-mediated oxidative stress from heme degradation may reduce beef water-holding capacity (WHC). However, the underlying mechanism of heme degradation is still unknown. In the present study, we assessed the WHC, tissue morphology, reactive oxygen species (ROS), apoptosis, heme oxygenase(HMOX) 1 expression, and ferroptosis characteristics of beef chilled at 4 °C for 6 days. Results showed that water loss increased and WHC decreased during beef storage (P < 0.05). Increased protein and mRNA expression of HMOX1 promoted the decomposition of heme and facilitated the liberation of iron ions (P < 0.05), and excess LMW-Fe was associated with ROS formation, depletion of glutathione, and inhibition of glutathione peroxidase 4 activity (P < 0.05). Muscle tissue showed typical features of ferroptosis, including expression of ferroptosis-related genes, malondialdehyde accumulation, and structural damage to mitochondria (P < 0.05). It was also found that HMOX1 and the heme pathway-mediated ferroptosis were associated with structural changes in myofibrils and reduced WHC in chilled beef.