中文摘要：

目的探讨高迁移率族蛋白1（HMGBl）基因沉默对氧糖剥夺／复氧导致的星形胶质细胞损伤的保护作用。方法将星形胶质细胞分为对照组、模型组、HMGB1siRNA组、非特异性siRNA组。模型组星形胶质细胞在无糖DMEM培养基、1％O，的培养条件下行2、4、6h的氧糖剥夺后复氧至24h。HMGBlsiRNA组星形胶质细胞在氧糖剥夺／复氧前转染载有HMGBl干扰序列的慢病毒，然后氧糖剥夺6h复氧至24h。采用RT．PCR和Westernblotting检测各组星形胶质细胞HMGBlmRNA及蛋白的表达状况，ELISA法测定星形胶质细胞培养上清液中HMGBl蛋白的浓度变化，并通过乳酸脱氢酶（LDH）漏出率、MTT法检测星形胶质细胞的损伤情况及存活率。结果RNA干扰可明显抑制星形胶质细胞HMGBl蛋白的表达（p〈0．01），RT．PCR及ELISA法检测显示，与对照组相比，模型组星形胶质细胞HMGBlmRNA表达量和细胞培养上清液中HMGBl的浓度均有所增加（P〈0．01），且随着氧糖剥夺时间的延长呈上升趋势（P〈0．01）。与对照组相比，模型组星形胶质细胞明显损伤，随着氧糖剥夺时间的延长，星形胶质细胞损伤加重，LDH漏出率逐渐增高（P〈0．01），存活率逐渐下降（P〈0．01）；与模型组相比，HMGBlsiRNA组细胞损伤明显减轻，LDH漏出率水平明显下降（P〈0．01），细胞存活率显著上升（P〈0．01）。结论通过RNA干扰技术可抑制星形胶质细胞HMGBl的表达。HMGBl过表达可能是氧糖剥夺／复氧后引起细胞损伤的重要因素之一。

英文摘要：

Objective To investigate the protective effect of high mobility group box 1 （HMGB1） gene silence on astrocyte injury caused by oxygen-glucose deprivation/reoxygenation （OGD/R） in vitro. Methods Astrocytes were divided into control group, OGD/R group and HMGB1 siRNA group. Astrocytes in OGD/R group were cultured with glucose free DMEM under 1% 02 condition, then they were treated with OGD for 2, 4 and 6h respectively, and then reoxygenated for 24h. In HMGB1 siRNA group, astrocytes that transfected with HMGB1 small interference RNA （siRNA） lentivirus-vector were treated with OGD 6h, and then reoxygenated for 24h. After 24h reoxygenation, the mRNA and protein expression of HMGB 1 in the astrocytes were determined by RT-PCR and Western blotting. HMGB1 protein in culture supernatant of astrocytes was determined by ELISA. The cell injury and survival rate were assessed by LDH activity （LDH%） and MTT assay. Results Compared with the astrocytes without transfection of HMGB 1 siRNA lentivirus-vector, the protein expression of HMGB 1 was suppressed by siRNA. Compared with the control group, with prolongation of the OGD time, the mRNA and protein expression of HMGB 1 increased gradually （P〈0.0S） after OGD/R, and it further increased with elapse of time. OGD resulted in significant injuries with time extention, and the LDH% increased （P〈0.05） with marked lowering of survival rate （P〈0.05）. Compared with the OGD/R group, cell injury in HMGB1 siRNA group alleviated remarkably, and survival rate was elevated si!~nificantly （P〈O.O1）. Conclusion The expression of HMGB1 in astrocvtes can be inhibited by siRNA, and over-expression of HMGB 1 might be an important factor in 0 GD/R-induced cell iniury.