Hydroxyoctadecadienoic acid as a potential biomarker for oxidative stress in patients with chronic hepatitis C

Background and Aim: The possible involvement of oxidative stress in hepatitis C virus (HCV)-induced liver damage and hepatocarcinogenesis has been reported. We have recently developed a novel method to measure total hydroxyoctadecadienoic acid (tHODE) and have proposed its usefulness as a biomarker for lipid peroxidation. The present study was undertaken to evaluate oxidative stress in HCV-infected liver diseases by several potential oxidative stress markers including tHODE and further to validate the biomarkers for evaluating the efficacy of iron reduction therapy. Methods: Total hydroxyoctadecadienoic acid, total 8-iso-prostagrandin F_2α (t8-iso-PGF_2α), selenoprotein P and other antioxidant compounds were measured in the plasma and erythrocytes obtained from 42 healthy controls and 78 HCV patients. Plasma levels of biomarkers and antioxidants were also assessed during the iron reduction therapy for 16 weeks in 12 HCV patients. Results: The concentrations of tHODE in the plasma and erythrocytes and t8-iso-PGF_2α in the plasma of chronic HCV-infected patients were significantly higher than those of healthy controls. Plasma levels of vitamin E and vitamin C of HCV-infected patients were lower than those of the controls. Furthermore, the plasma tHODE significantly correlated with serum aminotransferases and type IV collagen-7S domain in chronic HCV-infected patients. During the iron reduction therapy, the plasma levels of tHODE but not t8-iso-PGF_2α decreased and inversely its stereo-isomer ratio (ZE/EE) increased in parallel with the decreases of serum alanine aminotransferase, ferritin and α-fetoprotein. Conclusion: The levels of tHODE in chronic HCV-infected patients can be a useful biomarker for the evaluation of oxidative stress in chronic hepatitis C.