中文摘要：

目的：观察缺氧诱导因子-1α（HIF-1α）基因转染对HepG2细胞缺氧损伤的影响并初步探讨其作用机制。方法：腺病毒转染的人HepG2细胞常氧培养24h后分为4组：Ad—GFP转染常氧培养组（Ad—GFP transfected—normoxia组）、Ad—HIF转染常氧培养组（Ad—HIF transfected—normoxia组）、Ad—GFP转染低氧培养组（Ad—GFP transfected—hypoxia组）和Ad—HIF转染低氧培养组（Ad—HIF transfected—hypoxia组）。观察各组细胞的细胞活力、乳酸脱氢酶（LDH）释放率、细胞内活性氧（ROS）、一氧化氮（NO）含量和诱导型一氧化氮合酶（iN-0S）活力。结果：Ad—HIF转染的HepG2细胞可高效表达HIF-1α。Ad—GFP transfected—hypoxia组的细胞活力显著低于Ad—GFP transfected—nomloxia组（P〈0．05）；Ad—HIF transfected—hypoxia组的细胞活力与Ad—HIF transfected—normoxia组比较无显著差异。Ad—GFP transfected—hypoxia组细胞内ROS含量显著高于Ad—GFP transfected—normoxia组（P〈0．05）；Ad—HIF transfected—hypoxia细胞内ROS含量与Ad—HIF transfected—normox-ia组或Ad—GFP transfected—hypoxia组比较均无显著差异。Ad—HIF transfected—normoxia组和Ad—GFP trans—fected—hypoxia组细胞内NO含量和iNOS活力均显著高于Ad—GFP transfected—normoxia组（P〈0．05）；Ad—HIF transfected—hypoxia组细胞内NO含量和iNOS活力与Ad—GFP transfected—hypoxia组和Ad—HIF transfected—nor—moxia组比较无显著差异。结论：基础性HIF-1高表达可显著减轻缺氧时HepG2细胞的损伤程度，其机制可能与HIF-1高表达提高HIF-1调控的缺氧相关基因的基础表达水平和其产物含量有关；也可能与HIF-1高表达防止缺氧时ROS的过度增加有关。

英文摘要：

AIM： To study the protective effects of HIF -1α gene transfeetion on hypoxic injury in human HepG2 cells. METHODS： After gene transfection, HepG2 cells were randomly divided into 4 groups ： normoxia with Ad - GFP transfected group, normoxia with Ad - HIF - 1 transfected group, hypoxia with Ad - GFP transfected group and hypoxia with Ad - HIF - 1 transfeeted group. LDH leaking rate, cell viability, contents of NO and ROS, the iNOS activity were measured. RESULTS： High levels of HIF -1α mRNA and protein were detected in Ad - HIF transfected HepG2 cells. Cell viability was significantly lower in Ad - GFP transfected - hypoxia group than that in Ad - GFP transfeeted - normoxia group （ P 〈 0. 05 ）. No marked difference of cell viability was found between Ad - HIF transfected - hypoxia group and Ad - HIF transfected - normoxia group. ROS was significantly higher in Ad - GFP transfected - hypoxia group than that in Ad - GFP transfected - normoxia group （ P 〈 0. 05 ）, while no marked difference was found either between Ad - HIF transfected - hypoxia group and Ad - HIF transfected - normoxia group or between Ad - HIF transfected - hypoxia group and Ad - GFP transfected - hypoxia group. The content of NO and iNOS activity were significantly higher in Ad - HIF transfected - normoxia group and Ad - GFP transfected - hypoxia group than those in Ad - GFP transfected - normoxia group （ P 〈0. 05 ）, no marked difference was found either between Ad - HIF transfected - hypoxia group and Ad - GFP transfected - hypoxia group or between Ad - HIF transfected - hypoxia group and Ad - HIF transfected - normoxia group. CONCLUSION ： Higher HIF -1α expression is contributed to protective effects against hypoxic injury in HepG2 cells, the mechanisms of which may be correlated with promoting expression of gene regulated by HIF - 1 and restraining over - expression of injure factors.