Abstract

Cinnamophilin Inhibits Neutrophilic Respiratory Burst and Protects Against Ischemia-Reperfusion Brain Damage

Yu-Wen Lin, Shih-Huang Tai, Chih-Hao Tien, Sheng-Yang Huang, Che-Chao Chang, Tian-Shung Wu, Wei-Sheng Juan, Hung-Yi Chen and E-Jian Lee

We have shown that administration of Cinnamophilin (CINN) effectively reduced oxidative damage, DNA lipid peroxidation, neutrophil infiltration, and ischemic brain damage by inhibiting oxidative stress and the resulting inflammation in experimental stroke. In this study the potential CINN to ameliorate neutrophilic respiratory burst and reduce neutrophil infiltration was investigated. Neutrophils pretreated or co-treated with CINN, were stimulated by phorbol 12-myristate 13-acetate (PMA) and the levels of superoxide radical (O2-.) and hydrogen peroxide (H2O2) produced were determined by dihydroethidium (DHE) and dihydrorhodamine-123 (DHR) fluorescence assays, respectively, while myeloperoxidase activity (MPO) was measured by the guaiacol method. Our results showed that both pretreatment and co-treatment with CINN significantly inhibited H2O2 production in PMA-stimulated neutrophils. Additionally, cotreatment, but not pretreatment, with CINN effectively inhibited O2-. production in the PMA-stimulated neutrophils. Both treatments did not effectively reduce the MPO activity in neutrophil. Finally, animals treated with CINN at reperfusion brain insults significantly reduced brain infarction and neutrophil infiltration, as well as improved neurobehavioral outcome following cerebral ischemic reperfusion. These results support pluripotent neuroprotection actions offered by CINN against cerebral ischemia-reperfusion.