Retinal Ischaemia/Reperfusion: The Effect of Baicalein and its Underlying Therapeutic Mechanisms

1. Shu-Hua Wu (吳淑華)
2. Jorn-Hon Liu (劉榮宏)
3. Mi-Mi Chen (陳蜜蜜)
4. Yei-Ching Chen（陳怡均）
5. Huwa Lee（李驊）
6. Hsiao-Ming Chao（趙效明）

1. Department of Ophthalmology, Cheng Hsin General Hospital, Taipei 振興醫院眼科
2. Institute of Pharmacology, School of Medicine, National Yang-Ming University, Taipei國立陽明大學藥理學研究所

Purpose: The aim of this study was to determine whether baicalein can act as a neuroprotectant against a retinal ischemic insult. Such an insult is thought to play an important role in retinal artery/vein occlusion，glaucomatous optic neuropathy, diabetic retinopathy, and so on.

METHODS: The methods included are electroretinogram (ERG), molecular biology, and immunohistichemistry.

RESULTS: Present results have indicated that 60 minutes of retinal ischemia plus reperfusion caused retinal damage characterized by a decline in electroretinographic b-wave amplitude, a reduction in choline acetyltransferase (amacrine cell biomarker) immunoreactivity and an increase in vimentin (Müller cell injury marker) immunoreactivity. The level of MMP-9 mRNA on 60/120 minutes or HIF_1α on 90/120 minutes was also up-regulated. What is more, these damages were blunted when baicalein was applied 15 minutes before ischemia.

CONCLUSIONS: This study supports a possible neuroprotective role for baicalein against retinal ischaemia, possibly, acting through down-regulating the ischaemia-induced MMP-9/HIF_1α mRNA over-expression.