Aspirin Attenuates Cerebral Ischemic Injury in Diabetic Rats

Abstract

Diabetes is an independent risk factor for ischemic stroke. Large randomized trials have shown that aspirin reduces stroke risks in patients with diabetes. However, there was no study that reported whether aspirin could attenuate the cerebral ischemic injury when administered prior to cerebral ischemia in diabetes. The objective of the present study was to evaluate the effects of aspirin on focal cerebral ischemia in diabetic rats. Diabetic rats received an oral administration of aspirin for 7 d prior to be subjected to a permanent middle cerebral artery occlusion (MCAO). The infarct volume of the brain was assessed in brain slices stained with 2% solution of triphenyltetrazolium chloride. Behavioral tests were used to evaluate the damage to the central nervous system. Platelet aggregation induced by adenosine diphosphate was measured. The results showed that aspirin at a dose of 30 mg/kg but not 10 mg/kg significantly reduced infarct volume and decreased neurological deficit scores compared with vehicle treatment. Aspirin (30 mg/kg) treatment also reduced platelet aggregation. Administration of aspirin did not alter the levels of blood glucose and insulin in diabetic rats. The findings suggest that pretreatment with aspirin may be effective to attenuate cerebral ischemic injury in diabetic patients.

Key words

aspirin - diabetes - cerebral ischemia

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