Adenoviral transfer of the heme oxygenase-1 gene protects striatal astrocytes from heme-mediated oxidative injury

• Main Authors: Zhi-Ping Teng, Jing Chen, Lee-Young Chau, Nicholas Galunic, Raymond F. Regan
• Format: Article
• Language: English
• Published: Elsevier 2004-11-01
• Series: Neurobiology of Disease
• Subjects: Free radical; Hemoglobin; Hemorrhage; Iron; Mouse; Oxidative stress
• Online Access: http://www.sciencedirect.com/science/article/pii/S0969996104001640

Heme oxygenase-1 (HO-1) is induced in the CNS after hemorrhage, and may have an effect on injury to surrounding tissue. Hemin, the preferred substrate of HO, is a neurotoxin that is present in intracranial hematomas. In a prior study, we observed that HO inhibitors increased the vulnerability of cultured cortical astrocytes to heme-mediated oxidative injury. To investigate the effect of HO more specifically, we used an adenoviral vector encoding the human HO-1 gene to specifically increase HO-1 expression. Incubation with 100 MOI of the HO-1 adenovirus (Adv-HHO-1) for 24 h increased both HO-1 protein and HO activity; a control adenovirus lacking the HO-1 gene had no effect. Using a DNA probe that was specific for human HO-1, 80.5 ± 7.2% of astrocytes were observed to be infected by in situ hybridization. The cell death produced by 30–60 μM hemin was significantly reduced by pretreatment with 100 MOI Adv-HHO-1, as assessed by LDH release, propidium iodide exclusion, and MTT reduction assay. The threefold increase in cell protein oxidation produced by hemin was also attenuated in cultures pretreated with Adv-HHO-1. These results support the hypothesis that HO-1 protects astrocytes from heme-mediated oxidative injury. Specifically increasing astrocytic HO-1 by gene transfer may have a beneficial effect on hemorrhagic CNS injury.