Glutathione peroxidase (Gpx) is a selenium-containing enzyme that catalyses the reduction of a variety of biological peroxides at the expense of reduced glutathione (GSH). Gpx1 is the most abundant isoform and its role has been implicated in neurodegenerative disorders such as Parkinson’s disease (PD), dementia with Lewy bodies tissue (DLB) (Power and Blumbergs, 2009) and traumatic brain injury (Tsuru-Aoyagi et al., 2009). Due to its high abundance, mutation of the Gpx1 allele would lower overall Gpx activity in the brain significantly. Gpx1 knockout (Gpx1-/-) mice do not show overt phenotypic differences, but all indications suggest that these mice are in a chronic “pro-oxidant” state (Cheng et al. 1999; de Haan et al. 2004). Indeed, a recent study from our laboratory illustrated that the absence of Gpx1 exacerbated stroke injury via increased ROS production and vascular permeability (Wong et al. 2008). Furthermore, Gpx1-/- mice demonstrated an increase in caspase-3 activation and greater infarct volume (Crack et al. 2001)
Microarray analysis was performed on the right striatum and cortex(corresponded to infarct area) of post-I/R injured brain tissues of Gpx1 -/- brains using Illumina mouse Ref8 V2 genechips. Suture-induced middle cerebral artery occlusion was induced for 2h followed by reperfusion, with tissue extraction taking place 2h, 8h and 24h post-reperfusion (n=4 respectively). Sham controls were included in this study too (n=4 respectively).