The aim of the present study was th

The aim of the present study was thus to investigate the neuroprotective capacity and the potential mechanisms of Cyperus esculentus L. orientin (CLO) from Cyperus esculentus L. leaves against ischemia/reperfusion (I/R) injury using standard orientin as control. For in vitro studies, we treated HT22 cells with CoCl2 as an in vitro ischemic injury model. HT22 cells in the control group were treated with CoCl2. For in vivo studies, we used rat models of middle cerebral artery occlusion, and animals that received sham surgery were used as controls. We found that CLO protected CoCl2-induced HT22 cells against ischemia/reperfusion injury by lowering lipid peroxidation and reactive oxygen species formation as well as decreasing protein oxidation.Overall, our present study showed that CLO attenuatedbrain water content and cerebral infarct volume in rats aftercerebral I/R injury. CoCl2-induced decrease in cell viabilitywas ameliorated by CLO and CLO itself did not show detectablecytotoxicity at the concentrations tested. Further studiesindicate that CoCl2-induced cell injury involves elevationin oxidative stress reflected by increased H2O2 production,enhanced lipid peroxidation, and augmented protein oxidation.However, CLO did not reduce the release of LDH norincrease the activity of SOD, and the reason is unknown, sowe will continue to explore its causes in the future. All theseoxidative stress parameters except SOD could be attenuatedby CLO. Moreover, in the presence of CLO, cell death, assessed by caspase-3 activity, was significantly decreased.It should be indicated that HT22 cells used in this study was mouse hippocampal neuronal cell line, while experimentalcerebral I/R models were established on the basis ofmiddle cerebral artery occlusion method, which mainly causesI/R injury within the cortex on the operated hemisphere.Therefore, to better integrate the in vivo and in vitro findingsof the present study, primary cortical neurons instead ofHT22 cells will need to be investigated in the future and theoutcome of primary cortical neuron culture in the presenceof COCl2 should be compared with that of ischemic stroke.It should also be pointed out that while our current studywas solely focused on animal models and cell cultures, theresults could lay foundation for future testing of CLO inhumans, where the neuroprotective effects of CLO in strokepatients could be evaluated following comprehensive analysison the potential toxic effects and risk of CLO in animalmodels.Taken together, our present study demonstrates that CLOhas neuroprotective effects against cerebral I/R injury. Theunderlying protective mechanisms of CLO against ischemicinjury and CoCl2-induced cell death mainly involve decreasein cellular oxidative stress. Our study may provide foundationfor future studying CLO as a therapeutic agent in clinicalstudies.