Gene expression spectrum in brain tissues of mice at different phases after ischemia-reperfusion injury

Lichun ZHOU; Chunjin GAO; Guozhong WANG

ABSTRACT

BACKGROUND:

Gene chip of expression spectrum is used to make contrastive analysis of the changes of gene expression of histocytes derived from different individuals, tissues, cell cycles, developmental stages, differentiating stages, physiological and pathological status, and stimulating conditions.

OBJECTIVE:

To investigate gene expression changes of cerebral tissues of mice at different phases after ischemia/reperfusion injury, and screen out and understand genes related to cerebral ischemic/reperfusion injury.

DESIGN:

A randomized and controlled animal study.

SETTING:

Laboratory of the Department of Hyperbaric Oxygen, Beijing Chaoyang Hospital affiliated to Capital University of Medical Sciences;Laboratory of Shanghai Biostar Gene Chip Co., Ltd.MATERIALS The experiment was performed in the Laboratory of Department of Hyperbaric Oxygen, Beijing Chaoyang Hospital affiliated to Capital University Medical Sciences, and the Laboratory of Shanghai Biostar Gene Chip Co., Ltd. from September 2002 to October 2003. Totally 20 male mice of C57BL/6 species were selected and randomized into 4 groups with 5 in each group 48-hour and 10-day sham-operation groups and 48-hour and 10-day cerebral ischemia-reperfusion groups.

METHODS:

The bilateral common carotid arteries of mice in cerebral ischemia/reperfusion group were blocked with clamp for 20 minutes to establish models of cerebral ischemia/perfusion injury. The bilateral common carotid arteries of mice in sham-operation group were separated without clamp. We killed the mice by breaking off their necks at the 48th hour and 10th day after operation. Expression changes of cerebral tissues of mice were detected with BiostarM-20 s gene chip of expression spectrum.MAIN OUTCOME

MEASURES:

Changes of gene expression of cerebral tissues of mice in each group.

RESULTS:

A total of 20 mice were involved in the result analysis. ①Differential expression gene in 48-hour sham-operation group and 48-hour cerebral ischemia/reperfusion group showed that the number of up-regulated expression genes was 30. Among them the most obvious up-regulated gene was related to DNA synthesis, repair and transcription. The number of down-regulated expression genes was 119. Among them the most obvious down-regulated gene was protein phosphatase 1 (PP1) gene related to cellular signal and transferrin protein. ② Differential expression gene between 10-day sham-operation group and 10-day cerebral ischemia/reperfusion group showed no up-regulated gene, but 7 down-regulated genes, and the most obvious down-regulated gene was the one that related to cell apoptosis.

CONCLUSION:

At the 48th hour after cerebral ischemia/reperfusion, upregulated gene is the one that related to DNA synthesis, repair and transcription, which is helpful for cerebral tissue repair after cerebral ischemia/reperfusion. Genes related to cell signal and transferrin are down-regulated, and can level off barrier of endothelial cells and relieve cerebral ischemia/reperfusion injury. At the 10th day after cerebral ischemia/reperfusion, cell apoptosis-related gene is down-regulated, and can accelerate apoptosis and aggravate injury of cerebral cells, which may be related to delayed neuronal necrosis.