Enhanced anti-inflammatory effect of fish myofibrillar protein by introducing pectin oligosaccharide and its molecular mechanisms

This study investigated the efficacy of glycation with edible uronic acid-containing oligosaccharides via the Maillard reaction to enhance the anti-inflammatory effect of fish myofibrillar protein (Mf). Lyophilized Mf was reacted with pectin oligosaccharide (PO, half of the total protein weight) at 60 °C and 35 % relative humidity for up to 12 h to produce glycated Mf (Mf-PO). After pepsin and trypsin digestion, the anti-inflammatory effect was assessed by measuring the secretions of proinflammatory cytokines in LPS-stimulated RAW 264.7 macrophages, and the anti-inflammatory effect of Mf was enhanced by PO-glycation without marked lysine loss and browning. The effects on the expressions of genes related to the LPS-stimulated signaling pathway in macrophages were also examined. PO-glycation suppressed LPS-stimulated inflammation by suppressing expression of cd14 and enhancing suppressive effect of Mf on the TLR4-MyD88-dependent inflammatory signaling pathway. Therefore, as an edible reducing sugar, PO could be an effective bioindustrial material for developing anti-inflammatory Mf. [Display omitted] •Pectin oligosaccharide (PO) composing galacturonic acid was obtained by pectinase.•Fish myofibrillar protein was glycated with PO (Mf-PO) by the Maillard reaction.•Mf-PO showed lower lysine loss and slighter browning.•PO-glycation enhanced the anti-inflammatory effect of Mf.•PO-glycation attenuated expression of cd14 and TLR4-MyD88-dependent pathway.