HAS REACTIVE OXYGEN A ROLE IN METHYLGLYOXAL TOXICITY - A STUDY ON CULTURED RAT HEPATOCYTES

The toxicity of methylglyoxal and its ability to generate reactive oxy gen species were investigated in cultured rat hepatocytes. Under aerob ic and anaerobic conditions methylglyoxal increased lactate dehydrogen ase (LDH) release and trypan blue uptake in a concentration dependent manner. Those concentrations of methylglyoxal causing cell injury (1 m M<) also caused the release of reactive oxygen species as indicated by peroxidase-catalyzed luminol chemiluminescence. Release of reactive o xygen was detectable only under aerobic conditions, and only became si gnificant when a large portion of the cells had already lost their via bility. It is concluded that methylglyoxal injures cultured rat hepato cytes and induces the generation of reactive oxygen species. The react ive oxygen species, however, are essentially not involved in methylgly oxal hepatotoxicity but are released by already severely injured cells .