F₂-isoprostane and 4-hydroxynonenal excretion in human bile of patients with biliary tract and pancreatic disorders

Objective: To assess parameters of lipid peroxidation in bile of patients with hepatobiliary and pancreatic diseases. Methods: F₂- isoprostanes (F₂-IPs) and 4-hydroxynonenal (4-HNE) were measured in bile collected during 31 ERCP procedures using gas chromatography/mass spectrometry. Results: In 11 subjects with normal ERCP (controls), bile contained significant amounts of F₂-IPs (188 ± 27 pg/ml) and 4-HNE (37.5 ± 8.0 ng/ml). In 10 individuals with bile duct stones, there was a 3-fold increase of F₂-IPs (523 ± 129 pg/ml; p < 0.05) and a 2.5-fold increase of 4-HNE (89.6 ± 18.0 ng/ml;p < 0.05). In 10 patients with various pancreatic diseases, bile F₂-IPs were also enhanced (545 ± 112 pg/ml; p < 0.01). There was no significant change in α-tocopherol, whereas β-carotene was decreased in biliary tract and pancreatic diseases (p < 0.05). Results of serum liver tests were normal with the exception of bilirubin, which was increased together with alkaline phosphatase. Concentrations of total lipids, phospholipids, and cholesterol did not differ significantly between the three groups. Conclusions: These data provide the first evidence in humans supporting the role of oxidative stress in the pathogenesis of biliary and pancreatic disease.