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

Area of Science:

• Meat science and post-mortem aging research.
• Biochemistry of oxidative stress and protein degradation.
• Molecular mechanisms of meat tenderization.

Background:

• Meat tenderization is a complex post-mortem aging process influenced by enzymatic and non-enzymatic factors.
• Peroxiredoxin 6 (Prdx6) exhibits non-selenium glutathione peroxidase (NSGPx) activity, potentially impacting meat quality.
• Understanding Prdx6's role is crucial for developing strategies to optimize beef aging and tenderness.

Purpose of the Study:

• To investigate the role of Prdx6-mediated NSGPx activity in beef tenderization during post-mortem aging.
• To evaluate the effects of oxidative stress modulators (H2O2, NAC, MA) on Prdx6 activity and meat quality.
• To identify molecular markers associated with accelerated tenderization.

Main Methods:

• Analysis of shear force, NSGPx activity, and protein abundance (HSP70, HSP27, troponin-T) in beef.
• Treatment of beef muscles with hydrogen peroxide (H2O2), N-acetylcysteine (NAC), mercaptosuccinic acid (MA), or saline (Control).
• Tandem Mass Tag (TMT)-based proteomics to identify differentially abundant proteins.

Main Results:

• MA treatment inhibited NSGPx activity, accelerated tenderization, upregulated HSP70, and increased troponin-T breakdown.
• H2O2 upregulated HSP70 and HSP27 within 6-12 h post-mortem.
• Proteomics identified proteins linked to cytoskeleton, extracellular matrix, amino acid metabolism, and apoptosis pathways.

Conclusions:

• Prdx6 activity significantly modulates oxidative stress pathways affecting beef tenderization.
• Inhibiting Prdx6 with MA enhances oxidative stress, accelerating troponin-T proteolysis and meat tenderness.
• MA treatment offers a viable strategy to reduce beef aging time by over 20% within 72 h post-mortem.