Scallop hydrolysates/κ-carrageenan hydrogels improve the alleviating effect of curcumin on DSS-induced colitis

Scallop (Patinopecten yessoensis) male gonad hydrolysates/κ-carrageenan (SK) double cross-linking network hydrogels were constructed as curcumin (Cur) delivery vehicles with good gel mechanical property and homogeneous honeycomb microstructures. Compared with Cur + DSS group, weight loss and colon length in SK-Cur + DSS group increased about 1.04 and 1.06 folds, while the disease active index (DAI) scores decreased about 13 %. Moreover, SK-Cur showed superior effect on intestinal barrier improvement, oxidative stress modulation, and inflammatory expression regulation, reflected by 1.1 folds increment of epithelial tight junction proteins, 16 % and 27 % decline in MPO and iNOS levels, 20 % decline in NF-κB expression, 4 %, 7 %, 6 % decline in TNF-α, IL-1β, IL-6 expression in serum, and 9 %, 20 %, 7 % decline in TNF-α, IL-1β, IL-6 expression in colon tissue. Furthermore, SK-Cur enriched alpha diversity and restored taxonomic composition with increasing Bacteroides and Verrucomicrobia abundance accompanied by decreasing Firmicutes in DSS-induced UC mice, roughly to a normal gut flora state.