Presenza della glutatione perossidasi plasmatica (plGPX) in pazienti affetti da epatite C

Abstract

In the past decade it became accepted that reactive oxygen metabolites (ROM’s) play a role in various tissues damages, thus in certain liver deseases as well hepatitis C. Hepatic cells, utilize the enzymatic system constituted by the glutathione peroxidase/glutathione reductase enzymes (GPX/GR), to reduce oxidative damages. In fact, the GPX enzyme utilizes GSH to reduce ROM’s. Interferon alpha (IFN) might be useful to reducing the oxidative stress, probably through an increase of reduced glutatione (GSH). Recent findings demonstrate that hepatitis C virus (HCV) encodes a GPX gene in a reading frame overlapping a known non structural gene, NS4b, of unidentified function.The HCV GPX sequence has features of both the plasma and cellular GPX types. Aim of our study was to demonstrate the presence of the plGPX in sera of patients with C hepatitis and with a various viremia level. Our results show the presence of plGPX in all the sera examinated. Particularly, there is a remarkable increase in the sera with an high viremia as respect the sera without a viral replication. Moreover, it is very interesting to observe that some of the sera without viral replication possess an high plGPX level. In the other side, some of the sera with an high viral replication have low plGPX levels. Starting from these results, it will be foundamental to evaluate whether the patients examinated are, or not, in terapeutic treatment. Moreover, since GPX is a target of the tumor suppressor protein p53, that activates the apoptotic process in mammalian cells, it will be very interesting to establish wether the plGPX detected in the sera is of viral source or is the plGPX present in the hepatocytes. In fact, the understandig of these cellular mechanisms might play an important role in the evolution of hepatic cirrosis to hepato carcinoma in patients with C hepatitis.

Keywords

• HCV, plGPX, C hepatitis