2-脱氧葡萄糖诱导大鼠内质网应激预处理模型的最佳剂量

Optimization of the dosage of 2-deoxy-glucose in the establishment of a mouse model of endoplasmic reticulum stress

目的探讨2-脱氧葡萄糖(2-deoxy-glucose,2-DG)诱导大鼠内质网应激模型的最佳剂量。方法选择Wistar雄性大鼠108只,体质量240～260 g,采用不同剂量2-DG建立大鼠内质网应激的模型,随机分为6组:2-DG 50、100、150、200 mg/kg组,假手术组,缺血再灌注组。2-DG组按工作浓度为50 mg/mL溶于双蒸水腹腔注射7d,假手术组和缺血再灌注组腹腔注射双蒸水7 d,于脑缺血再灌注后12 h处死,对各组大鼠进行神经行为学评分,采用HE染色观察脑组织的病理形态,免疫组化法和Westernblot法测定GRP78蛋白的表达,用PCR法检测GRP78mRNA的表达。结果与脑缺血再灌注组相比,2-DG各剂量组大鼠的神经行为学评分明显减低(P<0.01),而以100 mg/kg组评分减低最为明显(P<0.05);2-DG各剂量组能不同程度的改善大鼠脑海马CA1区神经细胞的核深染、核固缩程度,减少细胞及间质的水肿,使胞膜趋于清楚、形态接近正常、核仁清晰可见的神经细胞数目增多,而以2-DG100 mg/kg组的效果最为明显。2-DG各剂量组GRP78蛋白表达明显增加,与脑缺血再灌注组比较,差异有显著性(P<0.01),而以100 mg/kg剂量组的GRP78蛋白表达最高,与其他2-DG剂量组比较差异有显著性(P<0.05)。结论 2-DG对脑缺血再灌注所致的神经细胞损伤具有保护作用,其最佳剂量为100 mg/kg。2-DG具有诱导大鼠内质网应激的作用,其最佳剂量是100 mg/kg。

Objective To explore the optimal dosage of 2-deoxy-glucose（2-DG） in the establishment of a mouse model of endoplasmic reticulum stress.Methodes 108 healthy male SD rats were choosen and randomly divided into 6 groups： sham-operation group,ischemia-reperfusion group,2-DG 50 mg /kg group,2-DG 100 mg /kg group,2-DG 150 mg /kg group,2-DG 200 mg /kg group,using different dosage of 2-DG to set up models of endoplasmic reticulum stress.2-DG was dissolved in double distilled water on working concentration of 50 mg /mL and injected into the rat abdomen for 7 days.The sham-operation and ischemia-reperfusion groups were injected with distilled water instead of 2-DG.After ischemia-reperfusion for 12 h,the rats were killed and the neurological function of each group was evaluated and,the pathological changes were observed with HE staining,and the expression of GRP78 was detected by immunohistochemistry and Western blot.The expression of GRP78 mRNA was detected by RT-PCR.Results The scores of 2-DG groups were significantly decreased compared with that in the sham-operation and ischemia-reperfusion group（P 〈0.01）,and that of the 2-DG 100 mg /kg group decreased more obviously（P〈 0.05）.The 2-DG treatment improved the nerve cell damage,depicting cell membranes more clearly,forming normal cell appearance,and increased number of visible nucleoli in neurons.The improvement in the 2-DG 100 mg /kg group was most significant.The expression of GRP78 was significantly increased in 2-DG groups in comparison with the ischemia-reperfusion group（P〈 0.01）.Furthermore,the expression of GRP78 protein in the 2-DG100 mg /kg group was most increased compared with that in other 2-DG groups.Conclusions 2-DG has protective effect on cerebral ischemia-injured neurons and can induce endoplasmic reticulum stress in rat brain at the best dose of 100 mg /kg.