Lipid peroxidation in hepatocyte cell cultures: modulation by free radical scavengers and iron

Rat hepatocytes were isolated and then maintained in serum-free cell culture medium for 24 h. The amount of malondialdehyde (MDA) accumulated in the medium was assayed and used as a measure of lipid peroxidation. The activity of lactate dehydrogenase (LDH) and urea were measured in the medium and used as indicators of hepatocellular viability and function. The effects of iron; desferrioxamine mesylate (Desferal), an iron chelator; and mannitol, a hydroxyl free radical scavenger were investigated. The addition of iron, Fe2 resulted in a three-fold increase in the levels of MDA. Desferal inhibited the production of MDA and blocked the effect of Fe2+. Neither iron nor Desferal had any effect on LDH or urea levels. Mannitol had no effect on MDA or urea production, but caused a 4 to 8-fold increase in the LDH levels in the medium. The results show that iron is involved in the mechanism of lipid peroxidation in hepatocyte cultures but suggest that as a pathologic event lipid peroxidation is not expressed in terms of viability during the first 24 h of hepatocyte culture.