Lecithinized superoxide dismutase improves outcomes and attenuates focal cerebral ischemic injury via antiapoptotic mechanisms in rats.

BACKGROUND AND PURPOSE Recent studies have shown the antiapoptotic neuroprotective effects of lecithinized superoxide dismutase (PC-SOD) in different forms of brain injury. We tested the effects of PC-SOD in focal cerebral ischemia in the rat middle cerebral artery occlusion model (MCAO). METHODS Adult male Sprague-Dawley rats were treated with PC-SOD (0.3, 1.0, and 3.0 mg/kg) administered intravenously after 90 minutes of occlusion (beginning of reperfusion). Physiological parameters, neurological score, and infarct volume were assessed at 24 and 72 hours in 3 groups of animals: sham-operated (n=18), MCAO treated with vehicle (n=26), and MCAO treated with PC-SOD (n=37). Oxidative stress was evaluated by malondialdehyde assay, and the apoptotic mechanisms were studied by Western blotting. RESULTS PC-SOD treatment significantly reduced infarct volume and improved neurological scores at different time points compared with the vehicle-treated group. PC-SOD treatment decreased malondialdehyde levels, cytochrome c, and cleaved caspase 3 expression and increased mitochondrial Bcl-2 expression. CONCLUSIONS Inhibition of oxidative stress with PC-SOD treatment improves outcomes after focal cerebral ischemia. This neuroprotective effect is likely exerted by antiapoptotic mechanisms.