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

Abstract

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.

Serum paraoxonase and arylesterase activities in various forms of hepatitis B virus infection

“…The fact that the levels of both of these liver-based enzymes are decreased in hepatic disorders may suggest that enzymes are not synthesized in sufficient amounts because of cell damage. On the other hand, in previous studies, an increase in oxidative parameters was observed indicating that an oxidative damage is present in addition to infectious and inflammatory damage (27). Although antioxidants may increase as a response to this damage, their consumption may also be high in parallel with the severity of damage; hence they may have considerably low blood levels.…”

“…Keskin et al evaluated the correlation between PON1 and arylesterase and disease severity in cirrhotic liver patients and found lower enzyme activities in chronic hepatitis patients compared with the control group (26). In another study, Aslan et al reported significantly lower paraoxanase and arylesterase levels in chronic hepatitis B and C patients compared with controls (14,27). In these studies, hepatitis B and C were evaluated in the same group.…”

Investigation of the Association Between Paraoxonase-1 Gene Polymorphisms and Response to Therapy in Chronic Hepatitis C Patients

“…Yapılan çalışmalarda; karaciğerde sentezlendiği için, PON1'in kronik hepatitte aktivitesinin azaldığı ve bunun da oksidatif strese olan maruziyeti artırarak virusun etkisi sonucu oluşan karaciğer disfonksiyonuna katkıda bulunduğu gösterilmiştir 38,39 . Ülkemizde de, kronik hepatit ve sirozlu (HBV ve HCV'ye bağlı) hastalarla yapılan çalışmalarda, benzer şekilde PON1 seviyelerinin sağlıklı bireylere göre daha düşük olduğu belirlenmiştir 17,40,41 . Oksidatif stres; DNA ve RNA'da hasara ve karaciğer hücrelerinde ölüme neden olmakta, bunun sonucu olarak da KHC hastalarında enzimlerde yükselme, nekroinfl amasyon, siroz ve hepatoselüler kanser (HSK) gelişmektedir 7,42 .…”

“…Örneğin son yıllarda tanımlanan IL-28B gen polimorfi zminin, tedavi yanıtı üzerindeki etkisine dair önemli veriler mevcuttur [12][13][14][15] . Buna karşın PON1 polimorfi zmi ile KHC arasındaki ilişkinin araştırıldığı yayın sayısı oldukça kısıtlıdır 16,17 . Bu çalışmada, birçok kronik hastalığın fi zyopatolojisinde rol aldığı düşünülen PON1 enziminin 55. ve 192. bölgelerindeki aminoasit değişikliklerinin, kronik HCV enfeksiyonunda tedavi yanıtı üzerindeki etkisinin araştırılması amaçlanmıştır.…”

Evaluation of Paraoxonase 1 Activities in Patients Infected with Hepatitis C Virus Genotype 1b and Genotype 4 in the Kayseri Province of Turkey

“…This function of PON1 can be useful for monitoring of chronic hepatitis disease (1,7,8). In recent studies, it has been reported that serum PON1 may be significantly reduced in patients with chronic liver disease (7,9,10,11,12).…”