Experimental bile-duct ligation resulted in accumulation of oxidized low-density lipoproteins in BALB/c mice liver.

ABSTRACT

BACKGROUND AND AIM: Oxidized low-density lipoproteins (LDL), which are produced during oxidative stress by the process of lipid peroxidation, have also been proposed to have complex roles in many other immuno-inflammatory mechanisms. It has been shown that bile-duct ligation results in oxidative stress in the liver of animals. The aim of this study was to investigate if oxidized LDL are produced in the liver tissues of bile-duct-ligated mice. METHODS: Obstructive jaundice was induced in BALB/c mice by the ligation and division of the common bile duct. Liver concentrations of glutathione and malondialdehyde were measured in the sham-operated (n = 10) and bile-duct-ligated (n = 10) mice on the 10th day of obstructive jaundice. The presence of oxidized LDL in the liver tissue sections was evaluated using a special, novel immunofluorescent staining method. The final step was to explore the existence of oxidized LDL under fluorescent microscopy. RESULTS: Compared with sham-operated mice, jaundiced mice showed significantly higher levels of malondialdehyde and lower concentrations of reduced glutathione in the liver. While there was no staining in the sham-operated group, bile-duct ligation resulted in positive oxidized LDL staining in the liver tissues of mice. The present study testifies that bile-duct ligation results in oxidative stress and enhanced lipid peroxidation in the hepatic tissues of BALB/c mice and moreover, that oxidized LDL accumulate in the liver of mice with experimental obstructive jaundice. CONCLUSION: Oxidized LDL may be an important and direct indicator of ongoing oxidative stress and enhanced lipid peroxidation in obstructive jaundice. The potential roles of this finding were also discussed, briefly.