HMOX1 and cerebrotendinous xanthomatosis: Combined with the Western blotting technique to detect Nrf2 and Keap1 proteins in the kidney and brain tissues, Keap1 protein expression was elevated in the kidney and brain tissues of mice in the CTX group compared with the control group, while the expression levels of Nrf2 and HO-1 proteins were reduced (## p < 0.01 or ### p < 0.001), which could have been reversed by ICA administration.