NO modulation of AMP-activated protein kinase: A key player in regulating beef tenderness during post-mortem maturation

This study investigated the role of NO in regulating AMPK activity and beef tenderness during post-mortem maturation of bovine gluteus quadriceps. The study included treatments with L-NAME (NOS inhibitor), ODQ (sGC inhibitor), Compound C (AMPK inhibitor), and a saline control. Results showed a decline in NOS activity, NO, and cGMP levels over time (<i>P</i> < 0.05). The L-NAME group had lower NOS activity and NO levels compared to the control (<i>P</i> < 0.05). AMPK activity peaked at 6 h and then decreased, with the control group showing higher AMPK activity than the L-NAME and ODQ groups (<i>P</i> < 0.05). The shear force in the L-NAME group was higher than the control but lower than the Compound C group at 48 h (<i>P</i> < 0.05). Overall, NO was found to activate AMPK, leading to reduced shear force and improved beef tenderness, providing a basis for enhancing beef quality through endogenous factors.