Thiol-disulphide balance and total oxidant-antioxidant status in patients with chronic hepatitis C

To assess the dynamic thiol/disulphide homeostasis (DTDH) and total oxidant/antioxidant status in patients with hepatitis C virus (HCV) infection and to evaluate their association with HCV-RNA levels.

Levels of serum total thiol (TT), native thiol (NT), disulphide (DS), total oxidant status (TOS), total antioxidant status (TAS) and oxidative stress index (OSI) as oxidative stress markers were determined in 162 individuals, including 74 patients with HCV infection and 88 non-HCV controls. HCV genotypes and HCV-RNA levels of the patients were recorded.

The NT, TT and TAS levels and NT/TT ratio were significantly lower in the HCV group compared with the control group. On the contrary, DS, TOS and OSI levels and DS/NT and DS/TT ratios were significantly higher. Patients with high HCV RNA levels (> 650 000 IU/mL) had higher DS levels than patients with low HCV-RNA levels (<650 000 IU/mL). Genotype 1 was observed in 68.9% of patients with HCV. Levels of oxidative stress parameters were similar between genotype 1 and other genotypes (2, 3 and 5). No significant correlations were found between oxidative stress markers and albumin, alanine aminotransferase, aspartate aminotransferase, bilirubin and HCV-RNA levels in patients with HCV infection. A negative correlation was found only between OSI and albumin.

Our results suggest that DTDH shifts towards the DS direction because of thiol oxidation in HCV-infected patients. Furthermore, DS levels were significantly higher in patients with high HCV-RNA levels compared with patients with low HCV-RNA levels.