Pitavastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, reduces hippocampal damage after transient cerebral ischemia in gerbils

Summary.

Pitavastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, is a potent cholesterol-lowering drug that reduces the risk of myocardial infarction and stoke. In this study, we examined its neuroprotective effects against hippocampal CA1 neuronal damage following transient cerebral ischemia in gerbils. Forebrain ischemia was induced by occlusion of bilateral common carotid arteries for 5 min. Pitavastatin, at a dose of 3, 10 or 30 mg/kg, was administered orally twice a day for 5 consecutive days and transient cerebral ischemia was induced in mice 1 h after the last treatment with pitavastatin. Histopathological observations showed that neuronal damage to the hippocampal CA1 neurons, which was observed 5 days after ischemia in animals, was prevented by pitavastatin treatment. Immunohistochemical staining for copper/zinc superoxide dismutase (SOD) and manganese SOD decreased in the hippocampal CA1 sector of gerbils 2 days after ischemia when histological neuronal destruction was not yet found, but was clearly observed in pitavastatin-treated animals. These results indicate that pitavastatin can protect dose-dependently against ischemia-induced neuronal damage and that the mechanism of the neuroprotection may be related to the preservation of SODs, especially copper/zinc-SOD. This in part explains how pitavastatin therapy, which targets free radicals, has beneficial effects against disorders including ischemic stroke.