مرکز منطقه ای اطلاع رساني علوم و فناوري -

چكيده لاتين :

Isolated rat hepatocytes in culture were incubated with different concentrations of ironsorbitol (50, 100, 150, and 200 )lM) to assess the changes in reactive oxygen species (ROS) and lipid peroxidation leading to apoptotic hepatocyte cell death. The viability ofhepatocytes was declined depending on the iron concentration. One hour incubation of the cells with 100 )lM iron resulted in decreased of the hepatocyte viability down to 50% (ECso )lM). Cellular glutathione (GSH) was depleted depending on the concentration of iron added to the hepatocytes in culture. Decline in cellular GSH was associated with elevation in reactive oxygen species (ROS) generation and formation ofthiobarbituric acid reactive substances (TBARS) as index oflipid peroxidation. TBARS concentration was elevated in hepatocytes exposed to >100 )lM of iron for 40 min. A significant increase in ROS formation was also observed in cells incubated with 75 )lM of iron for 60 and 120 min. The consequences of ROS-mediated damages to hepatocytes were observed by DNA fragmentation, nuclear staining by propidium iddide and finally with induction of apoptotic hepatocyte cell death. Terminal deoxynucleotie transferase-mediated dUTP nick end labeling i.e. TUNEL assay (In situ- cell death-detection kit) and nuclear staining were also used to confirm apoptosis. These data clearly show that iron overload can cause apoptotic cell death in isolated hepatocytes and generation of ROS precedes other changes related to oxidative stress.