Copyright ©2009 The WJG Press and Baishideng. All rights reserved.
World J Gastroenterol. Apr 28, 2009; 15(16): 1929-1933
Published online Apr 28, 2009. doi: 10.3748/wjg.15.1929
Measurement of serum paraoxonase-1 activity in the evaluation of liver function
Jordi Camps, Judit Marsillach, Jorge Joven
Jordi Camps, Judit Marsillach, Jorge Joven, Centre of Biomedical Research, University Hospital Sant Joan, Institute of Health Research Pere Virgili, University Rovira i Virgili, 43201 Reus, Catalonia, Spain
Author contributions: Camps J drafted the manuscript; All the authors collected the scientific information, edited the manuscript and approved the final version.
Correspondence to: Dr. Jordi Camps, Centre of Biomedical Research, University Hospital Sant Joan, C. Sant Joan s/n, 43201 Reus, Catalonia, Spain. jcamps@grupsagessa.cat
Telephone: +34-977-310300  
Fax: +34-977-312569
Received: February 19, 2009
Revised: March 3, 2009
Accepted: March 10, 2009
Published online: April 28, 2009

Paraoxonase-1 (PON1) is an esterase and lactonase synthesized by the liver and found in the circulation associated with high-density lipoproteins. The physiological function of PON1 seems to be to degrade specific oxidized cholesteryl esters and oxidized phospholipids in lipoproteins and cell membranes. PON1 is, therefore, an antioxidant enzyme. Alterations in circulating PON1 levels have been reported in a variety of diseases involving oxidative stress including chronic liver diseases. Measurement of serum PON1 activity has been proposed as a potential test for the evaluation of liver function. However, this measurement is still restricted to research and has not been extensively applied in routine clinical chemistry laboratories. The reason for this restriction is due to the problem that the substrate commonly used for PON1 measurement, paraoxon, is toxic and unstable. The recent development of new assays with non-toxic substrates makes this proposal closer to a practical development. The present editorial summarizes PON1 biochemistry and function, its involvement with chronic liver impairment, and some aspects related to the measurement of PON1 activity in circulation.

Keywords: Lipoproteins, Liver cirrhosis, Liver function tests, Oxidative stress, Paraoxonase-1