Serum paraoxonase and arylesterase activities for the evaluation of patients with chronic hepatitis

The sensitivity of standard biochemical tests for liver function is low and insufficient for a reliable determination of the presence or absence of liver disease. The aim of the present study was to investigate serum paraoxonase and arylesterase activities and lipid hydroperoxide (LOOH) levels, and to find out that whether the measurement of serum paraoxonase and arylesterase activities would be useful as an index of liver function status in chronic hepatitis (CH). Fourty-four patients with CH (24 CHB and 20 CHC) and 38 controls were enrolled. Serum paraoxonase and arylesterase activities were detected spectrophotometrically. LOOH levels were measured by the FOX-2 assay. Serum paraoxonase and arylesterase activities were significantly lower in patients with CH than controls (p < 0.001 for both), while LOOH levels were significantly higher (p < 0.001). Paraoxonase and arylesterase activities were inversely correlated with LOOH levels (r = -0.394, p < 0.05; r =-0.362, p < 0.05, respectively). Fibrosis scores of CH patients were significantly correlated with paraoxonase and arylesterase activities and LOOH levels (r =-0.276, p < 0.05; r = -0.583, p < 0.001 and r = 0.562, p < 0.001, respectively). Our results indicated that decrease in the activities paraoxonase and arylesterase may play a role in the pathogenesis of CH. In addition, serum paraoxonase and arylesterase activities measurement may add a significant contribution to the liver function tests.