Background and purpose: Recent clinical studies suggest that 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) exert protective effects against nonhemorrhagic stroke. In a murine cerebral ischemia model produced by occlusion of the middle cerebral artery, statins were shown to reduce infarct size. However, the effect of statins on hypertension-based stroke is unknown. The purpose of this study is to clarify the effect of a statin on stroke in stroke-prone spontaneously hypertensive rats (SHR-SP), in which both cerebral hemorrhage and infarction occur.
Methods: We treated SHR-SP chronically from 4 weeks of age with cerivastatin (2 mg/kg per day by gavage) or vehicle. The physiological parameters, the incidence of stroke-associated symptoms, and mortality were assessed.
Results: At 14 weeks of age, the incidence (13+/-3% versus 37+/-8%; P<0.01) and the size of stroke (1.6+/-0.2 versus 2.2+/-0.1 arbitrary units; P<0.01) were significantly decreased by cerivastatin, although blood pressure and plasma cholesterol levels were not different. Moreover, stroke-associated symptoms and early mortality of SHR-SP were markedly reduced in the statin-treated group (mortality at the age of 15 weeks: 15% versus 50%; P<0.05). Statin treatment significantly reduced superoxide production from nonstroke parenchyma of brain and infiltration of inflammatory cells to the stroke lesions.
Conclusions: Our data show that a high dose of statin exerts protection against hypertension-based stroke and ameliorates the disease severity via inhibition of superoxide production and modulation of inflammation in brain.