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.