Natural zinc-rich oyster peptides ameliorate DSS-induced colitis via antioxidation, anti-inflammation, intestinal barrier repair, microbiota modulation, and SCFA accumulation

• Published in: Food bioscience Vol. 61; p. 104801
• Main Authors: Qu, Changfeng, Liang, Chen, Liu, Tianlong, He, Yingying, Ke, Ke, Miao, Jinlai
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2024
• Subjects: Gut microbiota; Intestinal barrier repair; Natural oyster zinc-rich peptide; SCFA; TLR4/NF-κB signaling pathway; Ulcerative colitis; TLR4/NF-κB signaling pathway; Gut microbiota; Intestinal barrier repair; Natural oyster zinc-rich peptide; SCFA; Ulcerative colitis
• ISSN: 2212-4292; 2212-4306
• DOI: 10.1016/j.fbio.2024.104801

Natural oyster zinc-rich peptide (OZP) was extracted and purified. The higher zinc concentration in natural OZP may be closely related to the high zinc affinity of amino acids containing Lys, His, Cys, Val, Arg and Ser residues. FTIR analysis indicated that amino, amide, carboxyl and carbonyl groups may contribute to the binding sites for zinc and peptides. Administration of OZP ameliorated the symptoms of DSS-induced ulcerative colitis (UC) in mice, including weight loss, colonic damage, mucosal edema, goblet cell exhaustion and crypt disappearance. Natural OZP suppressed oxidative stress by significantly reducing the level of NO, MDA and MPO as well as increasing SOD activity. The anti-inflammatory effects of OZP were associated with the inhibition of TLR4/NF-κB pathways by diminishing NF-κB, TLR4, COX-2, iNOS, TNF-α, IL-6 and IFN-γ and elevating IL-10. By promoting mucus secretion, repairing goblet cells and enhancing the expression of tight junction proteins including occludin, claudin-1 and ZO-1, natural OZP maintained the intestinal barrier function. Furthermore, natural OZP regulated the microbial composition by remarkedly enhancing the beneficial microbial abundance like Faecalibaculum, Odoribacter and Anaerostipes, which in turn led to a significant increase in SCFA production. Collectively, natural OZP exerted the synergistic capacity to protect against DSS-induced UC by improving antioxidation and anti-inflammation, repairing intestinal barrier and modulating intestinal microbiota and SCFA. [Display omitted] •High zinc level in natural OZP was linked to a strong affinity of amino acid residues.•Natural OZP prevented colonic damage in DSS-induced mice.•Natural OZP alleviated DSS-induced colitis by inhibiting oxidation and inflammation.•Natural OZP maintained the gut barrier by promoting mucus, goblet cells and TJ protein.•Natural OZP rebalanced intestinal microbiome and SCFA metabolism in colitis.