HMOX1 and acute kidney injury: In our previous studies, we have demonstrated that HHcy can exacerbate Cisplatin-induced AKI [11] and accelerate AKI to CKD progression by downregulating heme oxygenase-1 expression [12]; however, the relationship between HHcy and AKI, especially ischemia-reperfusion injury (IRI)-induced AKI, is far from clear.