Effect of Long-Term Intake of Dietary Titanium Dioxide Nanoparticles on Intestine Inflammation in Mice.

Early stage exposure of foodborne substances， such as brightening agent titanium dioxide nanoparticles (TiO NPs)， can cause long-term effects in adulthood. We aimed to explore the potential adverse effect of long-term dietary intake of TiO NPs. After feeding for 2-3 months from weaning， TiO NPs-exposed mice showed lower body weight and induced intestinal inflammation. However， this phenomenon was not observed in gut microbiota-removed mice. TiO NPs exposure rarely affected the diversity of microbial communities， but significantly decreased the abundance of several probiotic taxa including and . Additionally， TiO NPs aggravated DSS-induced chronic colitis and immune response in vivo， and reduced the population of CD4+T cells， regulatory T cells， and macrophages in mesenteric lymph nodes. Therefore， dietary TiO NPs could interfere with the balance of immune system and dynamic of gut microbiome， which may result in low-grade intestinal inflammation and aggravated immunological response to external stimulus， thus introducing potential health risk.