Identification of aminoreductones as active components in Maillard reaction mixtures inducing nuclear NF-κB translocation in macrophages

Abstract

Coffee, a highly processed food, and Maillard mixtures are able to activate nuclear factor kappaB translocation in macrophages via generation of hydrogen peroxide. In this study, a substructure library was prepared and used to identify Maillard products that are responsible for this effect. Three different Maillard reaction products with aminoreductone substructure (C(6)-aminoreductone, C(4)-aminoreductone, and aminohexose reductone) strongly induce nuclear factor kappaB translocation in macrophages. The effect was almost completely blocked by co-incubation with catalase, indicating that cellular activation was mediated by the ability of the test compounds to generate hydrogen peroxide. The cellular effect of a Maillard mixture, which was produced under conditions favoring aminoreductone formation, could be almost completely related to the presence of C(6)-aminoreductone.

Elucidation of mechanism of aminoreductone formation in the Maillard reaction of lactose

“…In the solution containing abundant amount of butylamine (317.50 and 635 mM), there was a possibility that Gal formed during heating could also be involved in the Maillard reaction with the butylamine excess leading to the formation of C 4 ‐AR (Pischetsrieder et al. 1998a; Wühr et al. 2010).…”

“…1998a), in the early stage of the Maillard reaction, it becomes a very important indicator for estimating the extent of Maillard reaction or the extent of heat treatment in milk. Moreover, AR was reported as an active component (Wühr et al. 2010).…”

“…For this reason, the concentration of Gal is predicted to be higher than that of AR. On the other hand, in the system containing abundant amount of amino compounds, redundant amino compounds can also react with Gal just at the moment it was formed leading to the formation of AR (Wühr et al. 2010).…”

Demonstration of the presence of aminoreductone formed during the Maillard reaction in milk

“…However, direct demonstration of the presence of AR in milk had not been accomplished previously because of the difficulty in isolation of an intact AR from milk protein. AR is labile and hence not suitable for enzyme hydrolysis and multiple extraction steps (Wühr et al, 2010). In order to achieve the practical application of the XTT assay in food industries, it is essential to demonstrate the presence of AR in milk.…”

“…Antioxidative activity of AR from lactose and N a -acetyllysine has also been 0308-8146/$ -see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.foodchem.2011.05.079 reported (Pischetsrieder, Rinaldi, Gross, & Severin, 1998), and AR from lactose and butylamine has been shown to be an active component inducing nuclear NF-jB translocation in macrophages (Wühr, Deckert, & Pischetsrieder, 2010). Thus, AR, which was formed during the Maillard reaction of lactose, can clearly affect the quality and function of foods such as milk and dairy products.…”