Mitochondria influence glycolytic and tricarboxylic acid cycle metabolism under postmortem simulating conditions

• Published in: Meat science 2021-02, Vol.172, p.108316-108316, Article 108316
• Main Authors: Matarneh, Sulaiman K., Yen, Con-Ning, Bodmer, Jocelyn, El-Kadi, Samer W., Gerrard, David E.
• Format: Article
• Language: English
• Subjects: Glycolysis; Isotope tracer; Mitochondria; TCA cycle
• ISSN: 0309-1740; 1873-4138
• DOI: 10.1016/j.meatsci.2020.108316

The purpose of this study was to test mitochondrial functionality under conditions simulating postmortem metabolism. Isolated mitochondria from porcine longissimus lumborum (LLM) and masseter (MM) muscles were incorporated into an in vitro model that mimics postmortem metabolism. pH and 13C-enrichment of glycolytic and tricarboxylic acid (TCA) cycle intermediates were evaluated at 0, 15, 30, 120, 240, and 1440 min. Addition of mitochondria to the in vitro model lowered its pH at 240 min compared with control. Reactions containing mitochondria had lower pyruvate and lactate [M + 2] and [M + 3] isotopomers at 240 and 1440 min than controls. Furthermore, LLM lowered the enrichment of [M + 2], [M + 3], and [M + 4]α-ketoglutarate at 1440 min compared with MM and control. Succinate [M + 2] and [M + 3] were greater in MM than the control and LLM. [M + 3]fumarate was greater in control at 240 and 1440 min than LLM and MM treatments. Our data indicated that mitochondria are capable of mobilizing pyruvate generated though glycolysis under conditions simulating muscle postmortem metabolism. •Mitochondria isolated from white and red muscles were incorporated to an in vitro model that mimics postmortem metabolism.•[13C6]glucose tracer was used to determine glucose flux through glycolysis and tricarboxylic acid cycle.•Mitochondria influenced the enrichment of glycolytic and tricarboxylic acid cycle intermediates.•Mitochondria isolated from red and white muscles had different enrichment profiles for α-ketoglutarate and succinate.