Systemic markers of lipid peroxidation and antioxidants in patients with nonalcoholic fatty liver disease

Objectives: The aim of the present study was to examine the systemic parameters of oxidative stress and antioxidants in patients with nonalcoholic fatty liver disease and investigate the relationship between these parameters and clinical and biochemical outcomes. Methods: Fifty-one male patients with nonalcoholic fatty liver disease (group I), 30 age-matched and body mass index (BMI)-matched healthy male subjects, and 30 age-matched male patients with chronic viral hepatitis (group II) were enrolled in the study. Results: Increased systemic levels of malondialdehyde and depletion of antioxidants such as coenzyme Q10, CuZn-superoxide dismutase, and catalase activity were observed in group I. Coenzyme Q10 and CuZn-superoxide dismutase correlated negatively with increasing necroinflammatory activity and fibrosis. Body fat was negatively associated with plasma coenzyme Q10 levels, while an inverse association was found between plasma catalase levels and TG. However, LDL was positively associated with plasma malondialdehyde levels. CuZn-superoxide dismutase levels were negatively associated with glucose, insulin, and HOMA-IR. In addition, the levels of CuZn-superoxide dismutase correlated significantly in a negative manner with BMI. Conclusions: Our results concerning correlations suggest that disturbances in BMI, body fat, and lipid metabolism may contribute to altered oxidative status in NAFLD, and insulin resistance may be related to decreased antioxidants in NAFLD as well as products of lipid peroxidation. However, although our results suggest interesting correlations, this different mostly weak relationships must be taken with caution.