HMOX1 and hereditary elliptocytosis: To examine the protective mechanism against oxidative stress induced by APAP, we measured antioxidant gene expression and found that Hmox-1, ThR, and Nqo1 expression was upregulated in a dose-dependent manner by 2 mM of APAP in the Phb1 HE group (Figs. 4A-4C).