目的 脑缺血属于常见的脑血管疾病之一,脑缺血再灌注时可造成脑功能严重受损。通过建立脑缺血再灌注动物的损伤模型对比健康水平寻找疾病生物标记物。方法 采用改进的Longa线栓法制备大鼠脑缺血-再灌注模型,造模24 h后,收集模型组与对照组大鼠的血浆及脑组织,检测血浆生化指标及对代谢物进行分析。采用脑切片与血浆生化指标证明造模成功后,采用气质联用方法针对大鼠血浆中游离脂肪酸进行靶向代谢组学研究,内标物选择十三烷酸(C13∶0),衍生化方法选用甲酯化,衍生化试剂选择浓硫酸/CH₃OH,抗氧化剂为2,6-二叔丁基-4-甲基苯酚(BHT),气相色谱柱选择非极性固定相。结果 对比模型组和空白组,得到了4种差异代谢物,分别为十六烷酸(C16∶0)、十八烷酸(C18∶0)、十八烯酸(C18∶1)和十八碳二烯酸(C18∶2),其在整个代谢通路中均上调。由相关代谢通路分析结果显示,亚油酸代谢通路在疾病过程中具有显著变化。结论 在脂肪酸合成代谢通路里,亚油酸代谢的途径在脑缺血再灌注病发与治疗过程中变化显著,通过控制亚油酸的水平可以达到预防以及治疗脑缺血再灌注损伤的效果。本实验通过对脑缺血再灌注损伤大鼠血浆进行测定,并对脑缺血再灌注损伤进行预后评估,探讨脑缺血再灌注损伤的成因及发病机制,并为疾病病理研究以及药物作用机制研究奠定基础。

OBJECTIVE To find disease biomarkers of cerebral ischemia by establishing cerebral ischemia-reperfusion injury model of rats and comparing with healthy rats. METHODS Cerebral ischemia-reperfusion model of rats was established by modified Longa′s intraluminal suture method. After 24 h of modeling, plasma and brain tissue from the model group and the control group were collected for plasma biochemical indicators and metabolites analysis. Brain slices and plasma biochemical indicators were used to demonstrate the successful modeling. Gas chromatography-mass spectrometry was adopted to conduct targeted metabolomics studies on free fatty acids in rat plasma, tridecanoic acid (C13∶0) and 2,6-di-tert-butyl-4-methylphenol (BHT) were added as internal standard and antioxidant during sample preparation. Methylation was carried out using concentrated sulfuric acid/CH₃OH as a derivatization reagent, and a non-polar stationary phase column was selected for chromatographic separation. RESULTS Comparing the model group with the blank group, four differential metabolites were obtained, namely palmitic acid, stearic acid, oleic acid and linoleic acid, which were up-regulated throughout the metabolic pathway. The RESULTS of the relevant metabolic pathway analysis showed that the linoleic acid metabolic pathway had significant changes in the disease process. CONCLUSION In the fatty acid anabolic pathway, the linoleic acid metabolic pathway changes significantly during the onset and treatment of cerebral ischemia-reperfusion. The effect of preventing and treating cerebral ischemia-reperfusion injury can be achieved by controlling the level of linoleic acid. This study evaluates the prognosis of cerebral ischemia reperfusion injury by measuring the plasma of model rats, explores its cause and pathogenesis, and laid a foundation for the study of disease pathology and the mechanism of drug action.