Basic Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jan 28, 2015; 21(4): 1108-1116
Published online Jan 28, 2015. doi: 10.3748/wjg.v21.i4.1108
Metabolic shift in liver: Correlation between perfusion temperature and hypoxia inducible factor-1α
Andrea Ferrigno, Laura Giuseppina Di Pasqua, Alberto Bianchi, Plinio Richelmi, Mariapia Vairetti
Andrea Ferrigno, Laura Giuseppina Di Pasqua, Alberto Bianchi, Plinio Richelmi, Mariapia Vairetti, Unit of Cellular and Molecular Pharmacology and Toxicology, Department of Internal Medicine and Therapeutics, University of Pavia, Pavia 27100, Italy
Author contributions: Ferrigno A, Vairetti M and Richelmi P conceived of the study, analyzed and interpreted the data, and drafted the manuscript; Di Pasqua LG and Bianchi A acquire the data; all authors revised and approved the final version of the manuscript.
Supported by Grant from Fondazione Cariplo, No. 2011-0439.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Andrea Ferrigno, PhD, Unit of Cellular and Molecular Pharmacology and Toxicology, Department of Internal Medicine and Therapeutics, University of Pavia, via Ferrata 9/A, Pavia 27100, Italy. andrea.ferrigno@unipv.it
Telephone: +39-3-82986451 Fax: +39-3-82986347
Received: June 20, 2014
Peer-review started: June 20, 2014
First decision: July 21, 2014
Revised: August 1, 2014
Accepted: September 29, 2014
Article in press: September 30, 2014
Published online: January 28, 2015
Processing time: 221 Days and 15.4 Hours
Abstract

AIM: To study at what temperature the oxygen carried by the perfusate meets liver requirements in a model of organ perfusion.

METHODS: In this study, we correlated hypoxia inducible factor (HIF)-1α expression to the perfusion temperature and the hepatic oxygen uptake in a model of isolated perfused rat liver. Livers from Wistar rats were perfused for 6 h with an oxygenated medium at 10, 20, 30 and 37 °C. Oxygen uptake was measured by an oxygen probe; lactate dehydrogenase activity, lactate release and glycogen were measured spectrophotometrically; bile flow was gravitationally determined; pH of the perfusate was also evaluated; HIF-1α mRNA and protein expression were analyzed by real time-polymerase chain reaction and ELISA, respectively.

RESULTS: Livers perfused at 10 and 20 °C showed no difference in lactate dehydrogenase release after 6 h of perfusion (0.96 ± 0.23 vs 0.93 ± 0.09 mU/min per g) and had lower hepatic damage as compared to 30 and 37 °C (5.63 ± 0.76 vs 527.69 ± 45.27 mU/min per g, respectively, Ps < 0.01). After 6 h, tissue ATP was significantly higher in livers perfused at 10 and 20 °C than in livers perfused at 30 and 37 °C (0.89 ± 0.06 and 1.16 ± 0.05 vs 0.57 ± 0.09 and 0.33 ± 0.08 nmol/mg, respectively, Ps < 0.01). No sign of hypoxia was observed at 10 and 20 °C, as highlighted by low lactate release respect to livers perfused at 30 and 37 °C (121.4 ± 12.6 and 146.3 ± 7.3 vs 281.8 ± 45.3 and 1094.5 ± 71.7 nmol/mL, respectively, Ps < 0.02), and low relative HIF-1α mRNA (0.40 ± 0.08 and 0.20 ± 0.03 vs 0.60 ± 0.20 and 1.47 ± 0.30, respectively, Ps < 0.05) and protein (3.72 ± 0.16 and 3.65 ± 0.06 vs 4.43 ± 0.41 and 6.44 ± 0.82, respectively, Ps < 0.05) expression.

CONCLUSION: Livers perfused at 10 and 20 °C show no sign of liver injury or anaerobiosis, in contrast to livers perfused at 30 and 37 °C.

Keywords: Anaerobiosis; Hypoxia inducible factor-1α; Ischemia; Liver transplantation; Machine perfusion

Core tip: Among the techniques developed to improve the preservation of marginal organs for transplantation, hypothermic perfusion is the preferred choice. We show that it is possible to perfuse a rat liver at 20 °C without incurring ischemia. We evaluated liver injury, energetic status, lactate release, and hypoxia inducible factor-1α expression. Results show that symptoms of ischemia appear at temperatures > 20 °C, whereas there is no detectable advantage below 20 °C. These findings have interesting implications in liver preservation; maintaining the liver in a mild metabolic state could be useful for pharmacologic treatment and regeneration of the energetic status in ATP-depleted organs.