Peptides from Amaranth suppressed intestinal inflammation via NF-kB

QUEREDA, MICAELA; SMALDINI PAOLA L; ORSINI DELGADO, LUCÍA; QUIROGA, ALEJANDRA; AÑON, MARIA CRISTINA; DOCENA GH

Taller; IUIS-ALACI IMMUNO-COLOMBIA; 2021

Biological, nutritional and health benefits of amaranth have been highlighted in the last years.Proteins of amaranth exert anti-hypertensive, anti-oxidant, anti-thrombotic and anti-proliferativeeffects.The aim of this study was to analyze the anti-inflammatory effect of peptides from amaranth on NF-kB intracellular pathway activation in intestinal epithelial cells, and in experimental intestinalinflammation, such as colitis and food allergy.Colon cell lines (Caco-2 and Caco-luc) were cultured with flagellin and amaranth peptides. CCL20-expression was evaluated by qPCR and NF-κB modulation was evaluation by light emission andqPCR, along with p65-nuclear translocation. In vivo studies included the oral administration of aformulation containing the peptide during the allergic sensitization or the colitis induction phase inBalb/c mice. Treatment efficacy was in vivo and in vitro evaluated.We found several peptides with anti-inflammatory capacity and we selected that with the highestability to suppress cell activation (decrease in CCL20 and light emission p<0.05). In vivo studiesshowed, an amelioration of the clinical score (p<0.01) in the food allergy mouse model, withinhibition of specific-IgE secretion (p<0.05) and negativitization of the cutaneous test (mean increasein footpad thickness control: 0.6mm vs peptide-treated: 0.3mm; p<0.05); intestinal nf-kb geneexpression was reduced (fold change=3; p<0.01) along with up-regulation of tfg-b and foxp3. In thecolitis mouse model, we found a decrease of the histologic score with a decrease expression andproduction of pro-inflammatory cytokines (IL-1b, Ccl20, TNF and IFNg, p<0.05) and a decrease inthe myeloperoxidase activity in the peptide-treated group compared to control (p<0.05). NF-κBpathway was also abrogated in the gut.In conclusion, our findings indicated that peptides from amaranth endowed mucosal antiinflammatoryproperties that suppressed the intestinal activation of NF-kB in Th1- and Th2-mediated inflammation.These findings led us to propose that this peptide might be included in the composition of a functionalfood.