Peroxiredoxin 6 (Prdx6) and oxidative stress in post-mortem beef tenderization: A proteomic perspective

This research explored the role of peroxiredoxin 6 (Prdx6)-mediated non‑selenium glutathione peroxidase (NSGPx) activity in modulating the tenderization process of beef during post-mortem aging, extending up to 168 h. Shear force, NSGPx activity, differential protein abundance, heat shock proteins (HSP70, HSP27), and troponin-T levels were analyzed in beef longissimus lumborum muscles treated with hydrogen peroxide (H₂O₂), N-acetylcysteine (NAC), mercaptosuccinic acid (MA), or saline (Control). MA treatment inhibited NSGPx activity and accelerated tenderization compared to NAC. Proteomics revealed that proteins differentially abundant between 0 and 24 h post-mortem were linked to cytoskeleton, extracellular matrix, amino acid metabolism, and apoptosis pathways.MA upregulated HSP70 abundance, oxidative stress, and troponin-T breakdown. H₂O₂ upregulated HSP70 and HSP27 abundance only within 6–12 h post-mortem. These results demonstrate that oxidative stress treatments modulate protein dynamics during aging, offering insights into strategies to enhance beef tenderness.

Significance

This study highlights peroxiredoxin 6 (Prdx6) as a crucial regulatory element that affects oxidative stress-associated pathways involved in the meat tenderization process during post-mortem beef aging. We demonstrate that inhibiting Prdx6's on‑selenium glutathione peroxidase (NSGPx) enzymatic activity with mercaptosuccinic acid (MA) increases HSP70 abundance and accelerates troponin-T proteolysis through enhanced oxidative stress and calcium signaling pathways. Conversely, antioxidant N-acetylcysteine (NAC) delays tenderization by preserving cytoskeletal integrity. Our TMT-based proteomics further identifies 35 core proteins linking extracellular matrix remodeling, amino acid metabolism, and apoptosis to tenderness modulation. These findings provide the first mechanistic evidence that targeted manipulation of Prdx6 activity can optimize beef aging efficiency. For the meat industry, MA treatment offers a science-driven strategy to reduce tenderization time by >20 % within 24–72 h post-mortem, lowering processing costs while maintaining quality. This work also establishes HSP70 and troponin-T degradation as novel biomarkers for real-time monitoring of oxidative stress in meat processing systems.