Lipid‐lowering activity and underlying mechanism of glycosylated peptide–calcium chelate prepared by transglutaminase pathway

Abstract

The compounds that promote calcium absorption and osteogenesis may have great potential in controlling adipogenesis and obesity. In this study, the glycosylated peptides–calcium chelate prepared from Crimson Snapper scale protein hydrolysates (CSPHs) and xylooligosaccharide (XOS) via transglutaminase pathway with calcium absorption promoting and osteogenic activities, named XOS‐CSPHs‐Ca‐TG, were used to explore the potential prebiotic effect and lipid‐lowering activity on 3T3‐L1 cells. The presence of XOS‐CSPHs‐Ca‐TG in pure cultures could significantly promote the proliferation of probiotics (Bifidobacterium adolescentis and Lactobacillus acidophilus), enabling them to enter the logarithmic growth phase 2–4 h earlier. Results of in vitro fermentation of mice intestinal flora further indicated that XOS‐CSPHs‐Ca‐TG increased the number of beneficial bacteria such as Bifidobacterium and Lactobacillus by 11.57% and 7.63%, respectively, and boosted the production of short‐chain fatty acids, thereby improving the colonization ability of the intestinal microbiota. Results of quantitative real‐time polymerase chain reaction confirmed that XOS‐CSPHs‐Ca‐TG achieved lipid‐lowering effects by accelerating calcium influx and activating the mitogen‐activated protein kinase/extracellular signal‐regulated kinases signaling pathway, thereby inhibiting the gene expressions of the downstream peroxisome proliferator‐activated receptors γ and CCAAT/enhancer‐binding protein α, and further attenuating the secretion of adipokines and controlling the expression of key lipases. These results suggest that glycosylated peptides–calcium chelates are potentially functional foods in lipid metabolism‐related disease prevention.