A glutenin protein corona ameliorated TiO nanoparticle-induced gut barrier dysfunction and altered the gut microbiota composition

Previously, we found that glutenin proteins formed a protein corona around food-grade titanium dioxide (TiO 2 ) nanoparticles. The protein corona would alter the gastrointestinal behavior and biological activity of the nanoparticles. Here, in this study, the influence of protein corona formation on the adverse effects of TiO 2 nanoparticles on gut barrier function using in vitro and in vivo assays and the potential mechanism were investigated and elucidated. Our findings showed that the presence of the protein corona mitigated gut barrier injury caused by TiO 2 nanoparticles while increasing gene expression for tight junction proteins; for example, in vitro gastrointestinal digestion and fermentation experiments showed that the glutenin-TiO 2 protein corona was relatively stable to digestion and influenced the composition of the gut microbiota. Specifically, the glutenin-TiO 2 protein corona increased the relative abundance of beneficial bacteria such as Bifidobacterium , Parasutterella , and Bacillus while reducing the relative abundance of harmful bacteria like Streptococcus . Moreover, the formation of the protein corona reduced the cytotoxicity of the TiO 2 nanoparticles to Caco-2 and RAW264.7 cells. Mechanistically, we found that the presence of the glutenin-TiO 2 protein corona decreased the production of reactive oxygen species and increased the mitochondrial membrane potential in both Caco-2 and RAW264.7 cells compared to TiO 2 nanoparticles alone. This study provides valuable mechanistic insights into the potential biological effects of protein corona formation around food inorganic nanoparticles in the food industry. The formation of glutenin protein corona alleviated gut microbiota dysbiosis, increased the short chain fatty acid production, improved the gut barrier function, mitigated mitochondrial dysfunction, and reduced reactive oxygen species.