Paraoxonase-1 (PON1) is an esterase and lactonase synthesized by the liver and found in the circulation
associated with high-density lipoproteins (HDL). The physiological function of PON1 seems to degrade
specific oxidized cholesteryl esters and oxidized phospholipids in lipoproteins and cell membranes.
Alterations in circulating PON1 levels have been reported in a variety of diseases involving oxidative
stress including chronic liver diseases. The aim of this work has been planned to demonstrate: the PON1
activity in cirrhosis and non alcoholic steatohepatitis (NASH). This study was carried out on 40 Patients
from Internal Medicine clinic, Suez Canal University Hospital, divided in two groups; 20 patients
suffering from cirrhosis (Cirrhosis group) and 20 patients suffering from NASH (NASH group) in
addition to 20 healthy subjects free from any disease as control group. Fasting blood sugar, lipid profile
and liver function tests were performed in all groups using colorimetric methods, PON1 activity was
measured colorimetri-cally using paraoxon as a substrate and apolipoprotein A1(ApoA1) using
nephlometric method. PON1 activity and ApoA1 levels were significantly decreased in cirrhosis and
NASH patients compared to controls. Cirrhotic patients demonstrated normal lipid profile compared to
their controls except HDL which demonstrated low levels while dyslipidemia was demonstrated in
NASH patients. High levels of ALT and AST were demonstrated in the two patients groups with low
levels of albumin and high levels of total and direct bilirubin in cirrhotic patients only compared to the
controls. PON1 activity was found positively correlated with ApoA1 in the two patients groups while it
was found positively correlated with HDL and negatively correlated with LDL in NASH group only.
PON1activity and ApoA1were significantly reduced in cirrhosis and NASH patients compared to their
controls. Dyslipidemia is associated with patients of NASH. A positive correlation was seen between
PON1 activity and Apo A1 in the two discussed diseases.