1,6-二磷酸果糖对缺血性脑损伤保护机制的研究

The protective mechanism of fructose-1, 6-diphosphate on ischemic brain injury

目的 探讨 1,6 二磷酸果糖 (FDP)对缺血性脑组织损伤的保护机制。方法 利用大鼠局灶性脑缺血模型 ,采用TTC染色、免疫组织化学染色、Western印迹法和TUNEL染色技术 ,观察FDP对脑梗死面积、缺血区脱嘌呤 /脱嘧啶核酸内切酶 (APE/Ref 1)表达水平以及缺血区细胞凋亡程度的影响。结果 1,6 二磷酸果糖可显著性减少脑梗死面积 (31 0mm2 ± 2 9mm2 与 4 7 3mm2 ± 6 0mm2 )。可减少缺血半暗带TUNEL阳性细胞数量 ,缺血 2 4h组与FDP干预组分别为 6 9 3± 2 4个 /mm2 与4 2 8± 1 7个 /mm2 。上调缺血半暗带APE/Ref 1蛋白的表达 :缺血 2 4h组与FDP干预组比较APE/Ref 1免疫阳性细胞数分别为 2 6 3± 2 9个 /mm2 与 4 7 0± 3 4个 /mm2 ;Western印迹法光密度扫描值分别为 5 3± 3 2与 13 8± 5 4。结论 FDP可通过上调脱嘌呤 /脱嘧啶核酸内切酶表达水平 ,增强脑组织对缺血损伤的修复能力 ,减少缺血半暗带细胞凋亡发生 ,阻止脑梗死范围进一步扩大 。

Objective To explore the protective mechanism of fructose 1, 6 diphosphate (FDP) on ischemic brain injury. Methods A model of permanent focal cerebral ischemia was performed in rats by intraluminal filament occlusion of middle cerebral artery. TTC staining, immunohistochemistry, Western blotting, and TUNEL staining were used to evaluate the effect of FDP on infarct area, apurinic/apyrimidinic endonuclease (APE/Ref 1) expression, and apoptosis in ischemic brain tissue. Result The infarct areas of FDP intervening group and ischemia for 24 h group were 31.0±2.9 mm 2 and 47.3±6.0 mm 2 respectively. The numbers of TUNEL positive cells in ischemic penumbra were 69.3±2.4/mm 2 and 42.8±1.7/mm 2 in FDP group and ischemia for 24 h group respectively. FDP upregulated the expression of APE/Ref 1 protein in ischemic penumbra. The numbers of APE/Ref 1 immuno positive cells in the ischemia for 24 h group and FDP group were 47±3.4/mm 2 and 26.3±2.9/mm 2 respectively. The values of optical density by Western blotting in these two groups were 5.3±3.2 and 13.8±5.4 respectively. The differences between these two groups were statistically significant. Conclusion Through upregulating the expression of APE/Ref 1 protein, FDP improves the repair ability of brain tissue in the course of ischemic injury and mitigated the quantity of apoptosis in penumbra, thus preventing the extension of cerebral infarcttion.