Effect of virgin olive oil plus acetylsalicylic acid on brain slices damage after hypoxia-reoxygenation in rats with type 1-like diabetes mellitus

Aspirin is the most widely used drug for the secondary prevention of ischemic stroke in patients suffering from diabetes mellitus. Moreover virgin olive oil (VOO) administration exerts a neuroprotective effect in healthy rat brain slices. The aim of the present study was to determine the possible influence of VOO administration to streptozotocin-diabetic rats (DR) on the neuroprotective effect of aspirin in rat brain. DR were treated during 3 months with saline, aspirin (2 mg/kg/day p.o.), VOO (0.5 mL/kg/day p.o.) or its association; a control normoglycemic group was treated with saline. Brain slices were subjected to oxygen–glucose deprivation before a reoxygenation period. All the treatments significantly reduced lactate dehydrogenase LDH efflux after reoxygenation (−54.1% for aspirin, −51.3% for VOO and −72.9% for aspirin plus VOO). Lipid peroxides in brain slices were also reduced after the treatment with aspirin (−17.90%), VOO (−37.3%) and aspirin plus VOO (−49.2%). Production of nitric oxide after reoxygenation was inhibited by all the treatments (−46.5% for ASA, −48.2% for VOO and −75.8% for ASA plus VOO). The activity of the inducible isoform (iNOS) was inhibited by the three types of treatment (−31.8% for ASA, −29.1% for VOO and −56.0% for ASA plus VOO). The main conclusion of our study is that daily oral administration of VOO to diabetic rats may be a natural way to increase the neuroprotective effect of aspirin in diabetic animals.