The relevance of oxidative stress in cirrhotic patients with different forms of hepatic encephalopathy

Abstract

While the exact ammonia-induced pathogenic mechanisms in hepatic encephalopathy (HE) are not completely understood, an increasing number of reports have lately been involved in studying the possible relevance of oxidative stress status in HE. Here we evaluated the levels of some oxidative stress markers (two main antioxidant enzymes: superoxide dismutase-SOD and glutathione peroxidase-GPX, as well as a lipid peroxidation marker: malondialdehyde-MDA) in thirty-six cirrhotic patients with overt HE (n=12) or minimal HE (n=24), as compared to a control age-matched group (n=19). We also included a group with cirrhosis without HE (n=42). Our results provide additional evidences of increased oxidative stress in both overt and minimal HE, as expressed by altered serum glutathione peroxidase antioxidant activity and increased levels of lipid peroxidation. Moreover, we demonstrated a significant correlation between the levels of the aforementioned oxidative stress markers and the severity of cirrhosis according to the Child and MELD scales, as well as with the venous blood ammonia level.

Keywords

• Hepatic encephalopathy
• oxidative stress