Ischemic stroke leads to severe brain damage and high mortality. Chlorogenic acid is a phenolic compound known to have neuroprotective properties. Bcl-2 family protein plays an important role in the regulation of apoptosis. We investigated whether chlorogenic acid exerts neuroprotective effects against ischemic injury by modulating Bcl-2 and Bax proteins. Middle cerebral artery occlusion (MCAO) was performed to induce cerebral ischemia and rats were injected intraperitoneally with phosphate buffered saline or chlorogenic acid (30 mg/kg) for 2 h after MCAO. Cortical tissues were collected 24 h after MCAO injury and reverse transcription-quantitative real time polymerase chain reaction and Western blot analyses were performed to investigate the expression of Bcl-2 and Bax. The regulation of Bcl-2 and Bax proteins by chlorogenic acid during glutamateinduced cell damage were examined. Cells were collected at 24 h after administration of glutamate (5 mM) and chlorogenic acid (10, 30, 50 μM). These results showed a decrease in Bcl-2 expression and an increase in Bax expression in MCAO animals, but chlorogenic acid treatment alleviated these changes by MCAO damage. Glutamate significantly reduced cell viability, and chlorogenic acid treatment alleviated this reduction in a dose-dependent manner. Glutamate induced a decrease in Bcl-2 expression and an increase in Bax expression, but chlorogenic acid treatment alleviated these changes. We found that chlorogenic acid alleviates changes in the expression of Bcl-2 and Bax proteins induced by brain injury. Therefore, our findings provide an evidence that chlorogenic acid has neuroprotective effects against MCAO damage by modulating Bcl-2 and Bax proteins.

서 론
재료 및 방법
    실험동물과 약물투여
    중간대뇌동맥폐쇄술 (middle cereberal artery occlusion,MCAO)
    정량적 역전사 중합효소연쇄 반응 (reverse transcriptionquantitativereal time polymerase chain reaction,RT-qPCR)
    웨스턴 블롯 분석 (Western blot)
    세포 배양 (cell culture)
    세포 생존성 분석 (Cell viability assay)
    통계 분석
결 과
    MCAO 동물에서 클로로겐산에 의한 Bcl-2와 Bax mRNA의변화
    허혈성 뇌손상시 클로로겐산에 의한 Bcl-2와 Bax단백질의 변화
    글루타메이트에 노출된 신경세포에서 클로로겐산의신경보호 효과와 Bcl-2와 Bax 단백질의 변화
고 찰
감사의 글

• Ju-Bin Kang(Department of Veterinary Medicine, College of Veterinary Medicine, Research Institute of Life Science, Gyeongsang National University, Jinju, 52828, Korea)
• Phil-Ok Koh(Department of Veterinary Medicine, College of Veterinary Medicine, Research Institute of Life Science, Gyeongsang National University, Jinju, 52828, Korea) Corresponding Author