HMOX1 and acute kidney injury: Western blot analysis also showed that Nrf2 and HO-1 expression were decreased in AKI and CO + AKI groups compared with control group (p < 0.01), whereas treatment with curcumin significantly increased the expression of Nrf2 and HO-1 compared with rats in the AKI and CO + AKI groups (p < 0.01 for each).