Elucidating the involvement of apoptosis in postmortem proteolysis in porcine muscles from two production cycles using metabolomics approach

Abstract

Apoptosis has been suggested as the first step in the process of conversion of muscle into meat. While a potential role of apoptosis in postmortem proteolysis has been proposed, the underlying mechanisms by which metabolome changes in muscles would influence apoptotic and proteolytic process, leading to meat quality variation, has not been determined. Here, apoptotic and proteolytic attributes and metabolomics profiling of longissimus dorsi (LD) and psoas major (PM) muscles in pigs from two different production cycles (July–Jan vs. Apr–Sep) were evaluated. PM showed higher mitochondrial membrane permeability (MMP), concurrent with less extent of calpain-1 autolysis and troponin T degradation and higher abundance of HSP27 and αβ-crystallin compared to LD (P < 0.05). Apr–Sep muscles showed concurrence of extended apoptosis (indicated by higher MMP), calpain-1 autolysis and troponin T degradation, regardless of muscle effects (P < 0.05). Metabolomics profiling showed Apr–Sep muscles to increase in oxidative stress-related macronutrients, including 6-carbon sugars, some branched-chain AA, and free fatty acids. Antioxidant AA (His and Asp) and ascorbic acid were higher in July–Jan (P < 0.05). The results of the present study suggest that early postmortem apoptosis might be positively associated with pro-oxidant macronutrients and negatively associated with antioxidant metabolites, consequently affecting meat quality attributes in a muscle-specific manner.

Characterizing the Flavor Precursors and Liberation Mechanisms of Various Dry-Aging Methods in Cull Beef Loins Using Metabolomics and Microbiome Approaches

“…In recent years, advancements in high-throughput analyses, such as metabolomics, have been adopted to determine changes in multiple biological systems, including the biochemical changes in meat products. Metabolomics analysis allows the profiling of small compounds (metabolites), elucidating the molecular changes responsible for meat quality development [3][4][5]. While limited, the utilization of metabolomics analysis has also been employed to identify compounds related to the meat flavor changes, showing increased concentration in small molecular flavor precursors (e.g., amino acids, nucleotides, vitamins, acids, and minerals) or decreased off-flavor related metabolites (e.g., terpenoids) in dry-aged beef products [2,6].…”

RNA-Seq exploration of the influence of stress on meat quality in Spanish goats

“…This interrelationship is evident by the fact that calpain-1 plays an important role in modulating apoptosis by activating caspase 3 53 , which in turn disintegrates the calpain-inhibitor, calpastatin 54 . While severe oxidative stress may also promote apoptosis and subsequent proteolysis resulting in meat tenderization, apoptosis occurring early postmortem may adversely affect organoleptic properties of meat due to its negative association with antioxidant metabolites 55 . Our study supports the earlier suggestion by Goncalves et al 56 that the differential gene networks related to proteolysis, calcium signaling, and apoptosis appear to be potential regulators of meat tenderness.…”

— Invited Review — Postmortem skeletal muscle metabolism of farm animals approached with metabolomics

“…This may be due to mitochondrial damage during post-mortem muscle aging. Studies focusing on mitochondria have suggested the involvement of reactive oxygen species (ROS) from dysregulated mitochondria in early postmortem muscle aging [52][53][54]. According to these results, ROS-induced postmortem mitochondrial degeneration leads to increased drip loss in beef meat.…”