Alterations of mineral metabolism and secondary pathology in rats fed Maillard reaction products

It is possible that some of the toxic effects ascribed to Maillard reaction products (MRPs) are secondary to gastrointestinal effects and not a consequence of direct chemical toxicity per se. The present studies examined the effect of feeding diets containing 5% or 10% of an MRP from a glucose-glutamate system. There was a dose-related increase in the incidence of nephrocalcinosis in animals fed the MRP, which resulted in much interstitial kidney damage in the most severely affected animals.
Mineral balance studies of rats fed 0.5% MRP suggested that the nephrocalcinosis was secondary to disturbances of calcium and magnesium metabolism and was not of toxicological significance per se. A more significant finding, however, was a reduction in zinc status in animals fed 0.5% MRP in a 12 d balance study as a result of increased urinary and faecal losses. Preliminary studies In vitro demonstrated that the glucose-glutamate MRP is capable of binding magnesium, calcium, zinc and copper.