The protective effects of melanoidins in adriamycin-induced oxidative stress in isolated rat hepatocytes

The importance of the antioxidants contained in foods is well recognized both for preserving the foods themselves and for supplying essential antioxidants in vivo. Among these, the melanoidins formed during food processing and storage represent a significant part of our diet, with an average intake of several grams per day. Melanoidins exhibit antioxidant properties in vitro through their protective effect against reactive oxygen species. Here we investigated the protective effect of the model glucose-glycine melanoidins on oxidative stress induced by adriamycin in hepatocytes isolated from rats. The study was performed by examining cell toxicity (lactate dehydrogenase) release in the medium, lipoperoxidation, protein oxidation, GSH and ATP levels. The addition of 50 (mu)g glucose-glycine melanoidins to the hepatocytes treated with 25 and 75 (mu)M of adriamycin decreased the cell oxidative damage. The cell toxicity, lipoperoxidation and the protein oxidation decreased significantly in the presence of melanoidins. The effect of melanoidins on the intracellular antioxidant GSH when co-incubated the adriamycin-hepatocytes with melanoidins resulted in a recovery of GSH levels. Furthermore, from the study of ATP levels we found that the damage to the mitochondria induced by adriamycin is decreased in the presence of melanoidins. According to these results, we suggest that melanoidins are capable of preventing cell oxidation. Based on these mechanisms, the ingestion of melanoidins present in food could be play a role important in the prevention of oxidative damage and prevention the diseases related to free radicals.