Intestinal Barrier Protective Study of Jujube Peel Polyphenols/Zein Complexes by a Combined Caco-2 Cell and Caenorhabditis elegans Model: A Perspective of Proteomics

Jujube peels have been recognized as a promising resource of several bioactive ingredients. The main composition of jujube peel polyphenols (JPP) has been identified as rutin, kaempferol-3-O-rutinosid, and salicylic acid. The JPP/zein complexes, whose bioavailability reached 69.73% ± 5.06% in vitro, have been formed successfully. The Caco-2 cell and Caenorhabditis elegans (C. elegans) models have been combined to detect the intestinal barrier protective effect of JPP and its complexes. Results showed that JPP/zein complexes contain better protection capability than JPP in both models. In the Caco-2 cell model, the complex relieved intestinal barrier damage by regulating the tight junction proteins. Moreover, the lysosome pathway has been activated, further regulating immune responses and lipid transportation, improving the barrier function of C. elegans after incubation with JPP/zein complexes according to the proteomics study. This work provides new insights into intestinal barrier protection with bioactive compounds.