HMOX1 and Alzheimer disease: Moreover, elevated iron was significantly associated with higher glutamine (r=0.89, p=0.039*), TfR (r=0.816, p=0.048*) and HO-1 (r=0.484, p=0.033*), but lower hypoxanthine (r=−0.904, p=0.035*) in AD (Fig. 11).