Neuroprotective effect of hemin and its molecular mechanism in the hippocampal organotypic tissue cultures after combined oxygen/glucose deprivation

Objective To investigate the neuroprotective role of hemin and its effect on the expression of neuroglobin(Ngb) and heme oxygenase-1(HO-1) in the hippocampal organotypic tissue cultures(HOTC) after combined oxygen/glucose deprivation(OGD).Methods SD rats,8～10-days old,were sacrificed for brain.HOTC were made and randomly divided into four groups,including HOTC,HOTC undergoing OGD(OGD),HOTC undergoing OGD following pretreatment with hemin(Hemin + OGD) and HOTC undergoing OGD following pretreatment with Znpp(Znpp+OGD).The expression of neuroglobin and HO-1 was detected with immunohistochemical technique and computer-assisted image analysis.Results In OGD group,hippocampal organotypic tissue lost normal structure and neurons were damaged severely,and the expression of Ngb protein and HO-1 protein were significantly stronger than that in the HOTC group.Pretreatment with hemin could effectively reverse the damage of the neurons,and accompanied with upregulation of Ngb protein and HO-1 protein expression.In contrast, pretreatment with Znpp,an HO-1 inhibitor,could aggravate the damage,and accompanied with reduction of Ngb protein and HO-1 protein expression.Conclusion Hemin has protective effect on injury induced by OGD in rat hippaocampal slices,which is associated with enhanced expression of neuroglobin via the upregulation of HO-1.