Evaluation of carbon tetrachloride-induced stress on rat hepatocytes by 31P NMR and MALDI-TOF mass spectrometry: lysophosphatidylcholine generation from unsaturated phosphatidylcholines

Carbon tetrachloride (CCl4) represents an excellent model to study oxidative injury of cells. It is widely accepted that hepatocellular injury is a consequence of the metabolic conversion of CCl4 into highly reactive, free radical intermediates. Among the direct toxic effects of CCl4, stimulation of lipid peroxidation and the binding of the electrophilic radicals to membrane lipids have been suggested to play important roles in the pathogenesis of irreversible cell damage. CCl4-induced liver damage was modeled in cultures of rat hepatocytes with the focus on alterations of phosphatidylcholine (PC). The PC acyl chain composition was analyzed by 31P NMR spectroscopy and MALDI-TOF mass spectrometry. The content of the membrane arachidonoyl PC was decreased by almost 30% after incubation of the cells with CCl4. This relative decrease was found to correlate with increased concentrations of the corresponding saturated lysophosphatidylcholine (LPC). It is concluded that LPC represents a useful biomarker of CCl4-mediated damaging of hepatocytes. It is also speculated that de novo biosynthesis of PC is influenced by CCl4.