Antioxidant and anti-inflammatory activities of Maillard reaction products isolated from sugar-amino acid model systems.

We investigated the antioxidant and anti-inflammatory activities of both crude and ultrafiltrated Maillard reaction (MR) products (MRPs) derived from sugar-amino acid MR models, comprising fructose (Fru), glucose (Glu) or ribose (Rib) reacted with glycine (Gly) or lysine (Lys), respectively. Crude MRPs derived from Glu-Lys showed the greatest capacity (P < 0.05) to inhibit nitric oxide (NO) and interleukin 8 (IL-8) production in interferon γ and phorbol ester-induced Caco-2 cells. Moreover, one ultrafiltrated fraction (MW < 1 kDa) recovered from Glu-Lys exhibited the greatest (P < 0.05) affinity to inhibit NO. This effect also corresponded to an inhibition of both iNOS transcription and translation. The NO and IL-8 inhibitory activities of crude MRPs were positively correlated with intracellular oxidation inhibitory activity. In conclusion, we have demonstrated an anti-inflammatory capacity of MRPs in inflamed Caco-2 cells that is specific to low molecular weight (MW < 1 kDa) Glu-Lys MRPs.