J Nath, et al. University Hospital Birmingham, University of Birmingham, UK
De novo metabolic pathways are active during hypothermic machine perfusion (HMP) according to data from a group of researchers at the University of Birmingham, UK.
The group investigated the degree of de novo metabolism that occurs during HMP by incorporating 13C-labelled glucose in the perfusion fluid of porcine kidneys, which were then subject to 6 hours of HMP on the LifePort Kidney Transporter.
Analysis of perfusate and tissue extracts found a significant quantity of 13C-labelled lactate present in the renal cortex cell extracts (10.5%) and perfusate (5.31%). In addition, the presence of labelled alanine (5.14%), glutamic acid (0.08%), glycine, acetic acid and malonic acid was also observed.
The results confirm the activity of metabolic pathways in this hypothermic hypoxic environment, while the presence of non-glycolytic pathway derivatives suggests that metabolism during HMP is more complex than previously thought. The identification of isotopic Krebs cycle derivatives, such as glutamic acid, demonstrates that sufficient oxygen is dissolved in the perfusate to facilitate some aerobic metabolism. The results confirm that isotopic labelled ex vivo organ perfusion studies are feasible and informative.