Similarly, in mice, TiO2 NPs disturbed plasma glucose homeostasis, marked by increased plasma glucose levels, and impaired glucose tolerance, with no difference in plasma insulin levels compared with untreated controls (Gu et al., 2015; Hu et al., 2015, 2016, 2018, 2019, 2020), TiO2 impaired activation of components of the insulin signaling pathway in mice (Gu et al., 2015; Hu et al., 2018, 2019, 2020). This evidence concerns the gene INS and Impaired glucose tolerance.