Whey protein/chlorogenic acid/high methoxy pectin water-in-oil-in-water emulsion alleviates DSS-induced ulcerative colitis in mice by regulating gut microbiota and LPS/TLR4/MyD88/NF-κB pathways

• Whey protein/chlorogenic acid/high methoxy pectin water-in-oil-in-water (CGA-WOW) emulsion can alleviate DSS-induced ulcerative colitis (UC); • CGA-WOW emulsion protect the intestinal barrier through the LPS/TLR4/MyD88/NF-κB pathway; • CGA-WOW emulsion increase the proportion of the Clostridiales bacterium CIEAF_020 and Muribaculum intestinale, and Akkermansia muciniphila; Chlorogenic acid shows remarkable therapeutic potential against UC, but it has poor oral bioavailability and low solubility. In this study, whey protein/chlorogenic acid/high methoxy pectin water-in-oil-in-water emulsion (CGA-WOW) exerted a significant alleviating effect on body weight loss, disease activity index score, and colon length in mice with ulcerative colitis (UC). Furthermore, it led to a reduction in the levels of lipopolysaccharides (LPS) and related pro-inflammatory factors, a decrease in malondialdehyde, and an enhancement in the activity of superoxide dismutase and glutathione within the serum. Meanwhile, CGA-WOW emulsion can protect the intestinal barrier and inhibit the expression of inflammation-associated MyD88 protein through the LPS/TLR4/MyD88/NF-κB signaling pathway. Moreover, CGA-WOW emulsion increased the proportion of the Clostridiales bacterium CIEAF_020 and Muribaculum intestinale , and Akkermansia muciniphila and improved the levels of propionic, butyric, isobutyric and valeric acid. Overall, CGA-WOW emulsion effectively enhanced intestinal barrier integrity and reduced intestinal inflammation by inhibiting the LPS/TLR4/MyD88/NF-κB signaling pathway.