Intake of some Maillard reaction products affects calcium bone deposition

Resumen del trabajo presentado al Workshop COST Action 927, celebrado en Praga (República Checa) del 1 al 2 de octubre de 2004.Adverse influence of MRP on mineral metabolism hava been frequently described due to the behaving of some brown polymeric pigments (melaniodins) as chelating agents for metal cations, formlng soluble and insoluble complexes. The influence of glucoselysine (GLO) and glucose-methionine (GMO) Maillard reaction products (40% moisture, 150ºC, 30 or 90 min; GL30, GL90; GM30 and GM90 samples, respectively) on calcium bioavailabllity was invastigated. A preliminary in vitro assay was carried out to analyse the effect of the browned products on calcium solubility; pH and ionic strength were mantained at intestinal conditions. Calcium balance was performed in rats fed diets containing a 3% of these products (control diet GL30, GL90, GM30 and GM90 diets respectively) for a 21 day period. Then animals were sacrificed and femurs and other organs wara removed to analyse calcium levals. MRPs from both systems did not seam to have mejor effects on Ca solubility, according to tha results of soma researchers. However, previous assays of our experimental group using casein asreactant demonstrated a decrease in Ca solubility. Calclum bioavailability resulted unmodified by the MRP intake, but changes in calcium metabollsm might occur, since a decrease In calcium concentration of femurs was observad. lt has been described a reduction in strength, lower weights, ashes and calcium in tha bones of rats fed a diet in which the main protein, casein, had been heat-damaged. lt was not observe any abnormal accumulations of calcium in the kidneys of the animals fed MRP that might lead to nephrocalcinosis, an effect described as a consequence from the consumption of browning foods. MRP chronic consumption should be taken into acccunt since, in the long term, bone health could be impaired.Peer reviewe