Effect of ischaemic preconditioning on genomic response to cerebral ischaemia: similarity to neuroprotective strategies in hibernation and hypoxia-tolerant states
Effect of ischaemic preconditioning on genomic response to cerebral ischaemia: similarity to neuroprotective strategies in hibernation and hypoxia-tolerant states
复制标题
DOI：
10.1016/s0140-6736(03)14412-1
复制
发表时间：
2003-09-27
期刊：
影响因子：
168.9
通讯作者：
Simon, RP
中科院分区：
文献类型：
--
作者：
Stenzel-Poore, MP;Stevens, SL;Simon, RP
导致缺血耐受的神经保护分子机制尚不完全清楚。识别参与这一过程的基因将为了解细胞存活和中风的治疗方法提供见解。我们建立了脑卒中小鼠神经保护模型，并进行了基因表达谱分析，以确定潜在的神经保护基因及其相关途径。方法每组8只小鼠分别进行大脑中动脉闭塞15 min（预处理）、60 min（损伤性缺血）或预处理72 h后进行损伤性缺血。从缺血和非缺血半球的皮质区域提取RNA。每种情况下产生三个池，并将RNA杂交到寡核苷酸微阵列上，以比较缺血和非缺血半球。采用Real-time PCR和western blots验证结果。进行了后续实验，以解决研究结果的生物学相关性。微阵列分析显示，在损伤性缺血、缺血预处理或两者之间，基因表达的变化几乎没有重叠。损伤性缺血诱导基因表达上调；57个基因中有49个（86%）在缺血半球表达增加。相比之下，预处理后的损伤性缺血导致明显的下调；61个调控基因中有47个（77%）表达降低。预处理导致的转录变化涉及代谢途径和免疫反应的抑制、离子通道活性的降低和血液凝固的降低。预适应重新编程对缺血性损伤的反应。其他人报道的类似变化支持一种进化保守的内源性反应，以减少血流量和氧气限制，如在冬眠期间所见。
Background Molecular mechanisms of neuroprotection that lead to ischaemic tolerance are incompletely understood. Identification of genes involved in the process would provide insight into cell survival and therapeutic approaches for stroke. We developed a mouse model of neuroprotection in stroke and did gene expression profiling to identify potential neuroprotective genes and their associated pathways.Methods Eight mice per condition were subjected to occlusion of the middle cerebral artery for 15 min (preconditioning), 60 min (injurious ischaemia), or preconditioning followed 72 h later by injurious ischaemia. RNA was extracted from the cortical regions of the ischaemic and non-ischaemic hemispheres. Three pools per condition were generated, and RNA was hybridised to oligonucleotide microarrays for comparison of ischaemic and non-ischaemic hemispheres. Real-time PCR and western blots were used to validate results. Follow-up experiments were done to address the biological relevance of findings.Findings Microarray analysis revealed changes in gene expression with little overlap among the conditions of injurious ischaemia, ischaemic preconditioning, or both. Injurious ischaemia induced upregulation of gene expression; 49 (86%) of 57 genes regulated showed increased expression in the ischaemic hemisphere. By contrast, preconditioning followed by injurious ischaemia resulted in pronounced downregulation; 47 (77%) of 61 regulated genes showed lower expression. Preconditioning resulted in transcriptional changes involved in suppression of metabolic pathways and immune responses, reduction of ion-channel activity, and decreased blood coagulation.Interpretation Preconditioning reprogrammes the response to ischaemic injury. Similar changes reported by others support an evolutionarily conserved endogenous response to decreased blood flow and oxygen limitation such as seen during hibernation.