Chrysin attenuates global cerebral ischemic reperfusion injury via suppression of oxidative stress, inflammation and apoptosis

Global cerebral ischemia is a leading cause of mortality worldwide. Several biomechanisms play a role in the pathology of cerebral ischemia reperfusion damage, such as oxidative stress, inflammation, apoptosis and excitotoxicity. Chrysin, a natural flavonoid with many important biological activities, was investigated in the present study for its possible neuroprotective properties in a rat model of global ischemia reperfusion. Male Wistar rats were allocated into three groups: sham-operated, ischemia/reperfusion, and chrysin (30 mg/kg) groups. All animals were subjected to ischemia for 15 min followed by reperfusion for 60 min, except for the sham-operated group. Rats were decapitated, then both hippocampi were rapidly excised to evaluate several biomarkers that reflect ischemic injury. The obtained results showed that pre-treatment with chrysin attenuated ischemia-induced oxidative stress by: (i) restoring the glutathione level; and (ii) depressing the levels/activities of thiobarbituric acid reactive substances, the hippocampal NADPH, as well as the xanthine oxidase. Exposure to chrysin also suppressed the inflammation accompanying the ischemia/reperfusion (I/R) damage, through increasing the interleukin-10 level, while decreasing the levels of both interleukin-6 and tumour necrosis factor-alpha. Moreover, an increase in Bcl2 and a decrease in both BAX and Hsp90 levels were recorded following chrysin exposure, which was also accompanied with elevated glutamate and aspartate levels. In conclusion, chrysin has demonstrated an anti-ischemic potential, through attenuation of the mechanisms underlying I/R injury. These data add to the knowledge on the significance of natural flavonoids as neuroprotective agents.