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

Abstract

Early stage exposure of foodborne substances, such as brightening agent titanium dioxide nanoparticles (TiO2 NPs), can cause long-term effects in adulthood. We aimed to explore the potential adverse effect of long-term dietary intake of TiO2 NPs. After feeding for 2-3 months from weaning, TiO2 NPs-exposed mice showed lower body weight and induced intestinal inflammation. However, this phenomenon was not observed in gut microbiota-removed mice. TiO2 NPs exposure rarely affected the diversity of microbial communities, but significantly decreased the abundance of several probiotic taxa including Bifidobacterium and Lactobacillus. Additionally, TiO2 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 TiO2 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.