The role of oxidants and antioxidative parameters in patients with hepatic encephalopathy

Abstract

Background: Hepatic encephalopathy is a serious neuropsychiatric complication of cirrhosis. Changes in the oxidative and anti-oxidative system and nitric oxide levels in brain tissue contribute to the development of symptoms related to HE and HE. Purpose of the study to reveal the alterations in oxidative, anti-oxidative system and nitric oxide levels in cirrhotic patients during and after hepatic encephalopathy periods.Methods: This was a randomized controlled double-blind study conducted in Erciyes University Hospital between 3 July 2010 and 30 March 2011. We investigated the oxidative and anti-oxidative stress parameters by quantification of total antioxidant capacity (TAC), total oxidant capacity (TOC), nitric oxide (NO), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), total thiol and xanthine oxidase (XO) levels in serum. We compared the group of patients with hepatic encephalopathy, post-hepatic encephalopathy (clinically recovered) and control groups (healthy control). \xa0Results: Thirty hepatic encephalopathy patients were studied. Serum levels of nitric oxide and xanthine oxidase were statistically significantly high in the hepatic encephalopathy group according to control group (p<0.031, and p<0.001, respectively). Serum thiol levels were significantly low in hepatic encephalopathy patients than the controls (p<0.001). Total oxidant capacity, total antioxidant capacity, glutathione peroxidase and superoxide dismutase levels were not significantly different in hepatic encephalopathy group than the controls. Serum thiol levels were low and serum NO levels were high in recovered clinically from hepatic encephalopathy group according to control group currently (p<0.001, p<0.001, respectively). Total antioxidant capacity, total oxidant capacity, glutathione peroxidase, superoxide dismutase and xanthine oxidase levels were similar in both groups (p>0.05). Total antioxidant capacity and especially xanthine oxidase levels were significantly decreased in recovered clinically from hepatic encephalopathy group compared to hepatic encephalopathy group (p<0.05, p<0.001, respectively).Conclusions: Oxidative system, in\xa0\xa0 systemic circulation, is activated during hepatic encephalopathy and changes in XO level during and after hepatic encephalopathy is very different. This parameter may be a potential marker in differential diagnosis of hepatic encephalopathy from other coma causes. Further investigation is needed.